1 | use crate::raw::{ |
2 | Allocator, Bucket, Global, RawDrain, RawExtractIf, RawIntoIter, RawIter, RawTable, |
3 | }; |
4 | use crate::{Equivalent, TryReserveError}; |
5 | use core::borrow::Borrow; |
6 | use core::fmt::{self, Debug}; |
7 | use core::hash::{BuildHasher, Hash}; |
8 | use core::iter::{FromIterator, FusedIterator}; |
9 | use core::marker::PhantomData; |
10 | use core::mem; |
11 | use core::ops::Index; |
12 | |
13 | /// Default hasher for `HashMap`. |
14 | #[cfg (feature = "ahash" )] |
15 | pub type DefaultHashBuilder = core::hash::BuildHasherDefault<ahash::AHasher>; |
16 | |
17 | /// Dummy default hasher for `HashMap`. |
18 | #[cfg (not(feature = "ahash" ))] |
19 | pub enum DefaultHashBuilder {} |
20 | |
21 | /// A hash map implemented with quadratic probing and SIMD lookup. |
22 | /// |
23 | /// The default hashing algorithm is currently [`AHash`], though this is |
24 | /// subject to change at any point in the future. This hash function is very |
25 | /// fast for all types of keys, but this algorithm will typically *not* protect |
26 | /// against attacks such as HashDoS. |
27 | /// |
28 | /// The hashing algorithm can be replaced on a per-`HashMap` basis using the |
29 | /// [`default`], [`with_hasher`], and [`with_capacity_and_hasher`] methods. Many |
30 | /// alternative algorithms are available on crates.io, such as the [`fnv`] crate. |
31 | /// |
32 | /// It is required that the keys implement the [`Eq`] and [`Hash`] traits, although |
33 | /// this can frequently be achieved by using `#[derive(PartialEq, Eq, Hash)]`. |
34 | /// If you implement these yourself, it is important that the following |
35 | /// property holds: |
36 | /// |
37 | /// ```text |
38 | /// k1 == k2 -> hash(k1) == hash(k2) |
39 | /// ``` |
40 | /// |
41 | /// In other words, if two keys are equal, their hashes must be equal. |
42 | /// |
43 | /// It is a logic error for a key to be modified in such a way that the key's |
44 | /// hash, as determined by the [`Hash`] trait, or its equality, as determined by |
45 | /// the [`Eq`] trait, changes while it is in the map. This is normally only |
46 | /// possible through [`Cell`], [`RefCell`], global state, I/O, or unsafe code. |
47 | /// |
48 | /// It is also a logic error for the [`Hash`] implementation of a key to panic. |
49 | /// This is generally only possible if the trait is implemented manually. If a |
50 | /// panic does occur then the contents of the `HashMap` may become corrupted and |
51 | /// some items may be dropped from the table. |
52 | /// |
53 | /// # Examples |
54 | /// |
55 | /// ``` |
56 | /// use hashbrown::HashMap; |
57 | /// |
58 | /// // Type inference lets us omit an explicit type signature (which |
59 | /// // would be `HashMap<String, String>` in this example). |
60 | /// let mut book_reviews = HashMap::new(); |
61 | /// |
62 | /// // Review some books. |
63 | /// book_reviews.insert( |
64 | /// "Adventures of Huckleberry Finn" .to_string(), |
65 | /// "My favorite book." .to_string(), |
66 | /// ); |
67 | /// book_reviews.insert( |
68 | /// "Grimms' Fairy Tales" .to_string(), |
69 | /// "Masterpiece." .to_string(), |
70 | /// ); |
71 | /// book_reviews.insert( |
72 | /// "Pride and Prejudice" .to_string(), |
73 | /// "Very enjoyable." .to_string(), |
74 | /// ); |
75 | /// book_reviews.insert( |
76 | /// "The Adventures of Sherlock Holmes" .to_string(), |
77 | /// "Eye lyked it alot." .to_string(), |
78 | /// ); |
79 | /// |
80 | /// // Check for a specific one. |
81 | /// // When collections store owned values (String), they can still be |
82 | /// // queried using references (&str). |
83 | /// if !book_reviews.contains_key("Les Misérables" ) { |
84 | /// println!("We've got {} reviews, but Les Misérables ain't one." , |
85 | /// book_reviews.len()); |
86 | /// } |
87 | /// |
88 | /// // oops, this review has a lot of spelling mistakes, let's delete it. |
89 | /// book_reviews.remove("The Adventures of Sherlock Holmes" ); |
90 | /// |
91 | /// // Look up the values associated with some keys. |
92 | /// let to_find = ["Pride and Prejudice" , "Alice's Adventure in Wonderland" ]; |
93 | /// for &book in &to_find { |
94 | /// match book_reviews.get(book) { |
95 | /// Some(review) => println!("{}: {}" , book, review), |
96 | /// None => println!("{} is unreviewed." , book) |
97 | /// } |
98 | /// } |
99 | /// |
100 | /// // Look up the value for a key (will panic if the key is not found). |
101 | /// println!("Review for Jane: {}" , book_reviews["Pride and Prejudice" ]); |
102 | /// |
103 | /// // Iterate over everything. |
104 | /// for (book, review) in &book_reviews { |
105 | /// println!("{}: \"{} \"" , book, review); |
106 | /// } |
107 | /// ``` |
108 | /// |
109 | /// `HashMap` also implements an [`Entry API`](#method.entry), which allows |
110 | /// for more complex methods of getting, setting, updating and removing keys and |
111 | /// their values: |
112 | /// |
113 | /// ``` |
114 | /// use hashbrown::HashMap; |
115 | /// |
116 | /// // type inference lets us omit an explicit type signature (which |
117 | /// // would be `HashMap<&str, u8>` in this example). |
118 | /// let mut player_stats = HashMap::new(); |
119 | /// |
120 | /// fn random_stat_buff() -> u8 { |
121 | /// // could actually return some random value here - let's just return |
122 | /// // some fixed value for now |
123 | /// 42 |
124 | /// } |
125 | /// |
126 | /// // insert a key only if it doesn't already exist |
127 | /// player_stats.entry("health" ).or_insert(100); |
128 | /// |
129 | /// // insert a key using a function that provides a new value only if it |
130 | /// // doesn't already exist |
131 | /// player_stats.entry("defence" ).or_insert_with(random_stat_buff); |
132 | /// |
133 | /// // update a key, guarding against the key possibly not being set |
134 | /// let stat = player_stats.entry("attack" ).or_insert(100); |
135 | /// *stat += random_stat_buff(); |
136 | /// ``` |
137 | /// |
138 | /// The easiest way to use `HashMap` with a custom key type is to derive [`Eq`] and [`Hash`]. |
139 | /// We must also derive [`PartialEq`]. |
140 | /// |
141 | /// [`Eq`]: https://doc.rust-lang.org/std/cmp/trait.Eq.html |
142 | /// [`Hash`]: https://doc.rust-lang.org/std/hash/trait.Hash.html |
143 | /// [`PartialEq`]: https://doc.rust-lang.org/std/cmp/trait.PartialEq.html |
144 | /// [`RefCell`]: https://doc.rust-lang.org/std/cell/struct.RefCell.html |
145 | /// [`Cell`]: https://doc.rust-lang.org/std/cell/struct.Cell.html |
146 | /// [`default`]: #method.default |
147 | /// [`with_hasher`]: #method.with_hasher |
148 | /// [`with_capacity_and_hasher`]: #method.with_capacity_and_hasher |
149 | /// [`fnv`]: https://crates.io/crates/fnv |
150 | /// [`AHash`]: https://crates.io/crates/ahash |
151 | /// |
152 | /// ``` |
153 | /// use hashbrown::HashMap; |
154 | /// |
155 | /// #[derive(Hash, Eq, PartialEq, Debug)] |
156 | /// struct Viking { |
157 | /// name: String, |
158 | /// country: String, |
159 | /// } |
160 | /// |
161 | /// impl Viking { |
162 | /// /// Creates a new Viking. |
163 | /// fn new(name: &str, country: &str) -> Viking { |
164 | /// Viking { name: name.to_string(), country: country.to_string() } |
165 | /// } |
166 | /// } |
167 | /// |
168 | /// // Use a HashMap to store the vikings' health points. |
169 | /// let mut vikings = HashMap::new(); |
170 | /// |
171 | /// vikings.insert(Viking::new("Einar" , "Norway" ), 25); |
172 | /// vikings.insert(Viking::new("Olaf" , "Denmark" ), 24); |
173 | /// vikings.insert(Viking::new("Harald" , "Iceland" ), 12); |
174 | /// |
175 | /// // Use derived implementation to print the status of the vikings. |
176 | /// for (viking, health) in &vikings { |
177 | /// println!("{:?} has {} hp" , viking, health); |
178 | /// } |
179 | /// ``` |
180 | /// |
181 | /// A `HashMap` with fixed list of elements can be initialized from an array: |
182 | /// |
183 | /// ``` |
184 | /// use hashbrown::HashMap; |
185 | /// |
186 | /// let timber_resources: HashMap<&str, i32> = [("Norway" , 100), ("Denmark" , 50), ("Iceland" , 10)] |
187 | /// .iter().cloned().collect(); |
188 | /// // use the values stored in map |
189 | /// ``` |
190 | pub struct HashMap<K, V, S = DefaultHashBuilder, A: Allocator = Global> { |
191 | pub(crate) hash_builder: S, |
192 | pub(crate) table: RawTable<(K, V), A>, |
193 | } |
194 | |
195 | impl<K: Clone, V: Clone, S: Clone, A: Allocator + Clone> Clone for HashMap<K, V, S, A> { |
196 | fn clone(&self) -> Self { |
197 | HashMap { |
198 | hash_builder: self.hash_builder.clone(), |
199 | table: self.table.clone(), |
200 | } |
201 | } |
202 | |
203 | fn clone_from(&mut self, source: &Self) { |
204 | self.table.clone_from(&source.table); |
205 | |
206 | // Update hash_builder only if we successfully cloned all elements. |
207 | self.hash_builder.clone_from(&source.hash_builder); |
208 | } |
209 | } |
210 | |
211 | /// Ensures that a single closure type across uses of this which, in turn prevents multiple |
212 | /// instances of any functions like RawTable::reserve from being generated |
213 | #[cfg_attr (feature = "inline-more" , inline)] |
214 | pub(crate) fn make_hasher<Q, V, S>(hash_builder: &S) -> impl Fn(&(Q, V)) -> u64 + '_ |
215 | where |
216 | Q: Hash, |
217 | S: BuildHasher, |
218 | { |
219 | move |val| make_hash::<Q, S>(hash_builder, &val.0) |
220 | } |
221 | |
222 | /// Ensures that a single closure type across uses of this which, in turn prevents multiple |
223 | /// instances of any functions like RawTable::reserve from being generated |
224 | #[cfg_attr (feature = "inline-more" , inline)] |
225 | fn equivalent_key<Q, K, V>(k: &Q) -> impl Fn(&(K, V)) -> bool + '_ |
226 | where |
227 | Q: ?Sized + Equivalent<K>, |
228 | { |
229 | move |x| k.equivalent(&x.0) |
230 | } |
231 | |
232 | /// Ensures that a single closure type across uses of this which, in turn prevents multiple |
233 | /// instances of any functions like RawTable::reserve from being generated |
234 | #[cfg_attr (feature = "inline-more" , inline)] |
235 | fn equivalent<Q, K>(k: &Q) -> impl Fn(&K) -> bool + '_ |
236 | where |
237 | Q: ?Sized + Equivalent<K>, |
238 | { |
239 | move |x: &{unknown}| k.equivalent(key:x) |
240 | } |
241 | |
242 | #[cfg (not(feature = "nightly" ))] |
243 | #[cfg_attr (feature = "inline-more" , inline)] |
244 | pub(crate) fn make_hash<Q, S>(hash_builder: &S, val: &Q) -> u64 |
245 | where |
246 | Q: Hash + ?Sized, |
247 | S: BuildHasher, |
248 | { |
249 | use core::hash::Hasher; |
250 | let mut state = hash_builder.build_hasher(); |
251 | val.hash(&mut state); |
252 | state.finish() |
253 | } |
254 | |
255 | #[cfg (feature = "nightly" )] |
256 | #[cfg_attr (feature = "inline-more" , inline)] |
257 | pub(crate) fn make_hash<Q, S>(hash_builder: &S, val: &Q) -> u64 |
258 | where |
259 | Q: Hash + ?Sized, |
260 | S: BuildHasher, |
261 | { |
262 | hash_builder.hash_one(val) |
263 | } |
264 | |
265 | #[cfg (feature = "ahash" )] |
266 | impl<K, V> HashMap<K, V, DefaultHashBuilder> { |
267 | /// Creates an empty `HashMap`. |
268 | /// |
269 | /// The hash map is initially created with a capacity of 0, so it will not allocate until it |
270 | /// is first inserted into. |
271 | /// |
272 | /// # HashDoS resistance |
273 | /// |
274 | /// The `hash_builder` normally use a fixed key by default and that does |
275 | /// not allow the `HashMap` to be protected against attacks such as [`HashDoS`]. |
276 | /// Users who require HashDoS resistance should explicitly use |
277 | /// [`ahash::RandomState`] or [`std::collections::hash_map::RandomState`] |
278 | /// as the hasher when creating a [`HashMap`], for example with |
279 | /// [`with_hasher`](HashMap::with_hasher) method. |
280 | /// |
281 | /// [`HashDoS`]: https://en.wikipedia.org/wiki/Collision_attack |
282 | /// [`std::collections::hash_map::RandomState`]: https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html |
283 | /// |
284 | /// # Examples |
285 | /// |
286 | /// ``` |
287 | /// use hashbrown::HashMap; |
288 | /// let mut map: HashMap<&str, i32> = HashMap::new(); |
289 | /// assert_eq!(map.len(), 0); |
290 | /// assert_eq!(map.capacity(), 0); |
291 | /// ``` |
292 | #[cfg_attr (feature = "inline-more" , inline)] |
293 | pub fn new() -> Self { |
294 | Self::default() |
295 | } |
296 | |
297 | /// Creates an empty `HashMap` with the specified capacity. |
298 | /// |
299 | /// The hash map will be able to hold at least `capacity` elements without |
300 | /// reallocating. If `capacity` is 0, the hash map will not allocate. |
301 | /// |
302 | /// # HashDoS resistance |
303 | /// |
304 | /// The `hash_builder` normally use a fixed key by default and that does |
305 | /// not allow the `HashMap` to be protected against attacks such as [`HashDoS`]. |
306 | /// Users who require HashDoS resistance should explicitly use |
307 | /// [`ahash::RandomState`] or [`std::collections::hash_map::RandomState`] |
308 | /// as the hasher when creating a [`HashMap`], for example with |
309 | /// [`with_capacity_and_hasher`](HashMap::with_capacity_and_hasher) method. |
310 | /// |
311 | /// [`HashDoS`]: https://en.wikipedia.org/wiki/Collision_attack |
312 | /// [`std::collections::hash_map::RandomState`]: https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html |
313 | /// |
314 | /// # Examples |
315 | /// |
316 | /// ``` |
317 | /// use hashbrown::HashMap; |
318 | /// let mut map: HashMap<&str, i32> = HashMap::with_capacity(10); |
319 | /// assert_eq!(map.len(), 0); |
320 | /// assert!(map.capacity() >= 10); |
321 | /// ``` |
322 | #[cfg_attr (feature = "inline-more" , inline)] |
323 | pub fn with_capacity(capacity: usize) -> Self { |
324 | Self::with_capacity_and_hasher(capacity, DefaultHashBuilder::default()) |
325 | } |
326 | } |
327 | |
328 | #[cfg (feature = "ahash" )] |
329 | impl<K, V, A: Allocator> HashMap<K, V, DefaultHashBuilder, A> { |
330 | /// Creates an empty `HashMap` using the given allocator. |
331 | /// |
332 | /// The hash map is initially created with a capacity of 0, so it will not allocate until it |
333 | /// is first inserted into. |
334 | /// |
335 | /// # HashDoS resistance |
336 | /// |
337 | /// The `hash_builder` normally use a fixed key by default and that does |
338 | /// not allow the `HashMap` to be protected against attacks such as [`HashDoS`]. |
339 | /// Users who require HashDoS resistance should explicitly use |
340 | /// [`ahash::RandomState`] or [`std::collections::hash_map::RandomState`] |
341 | /// as the hasher when creating a [`HashMap`], for example with |
342 | /// [`with_hasher_in`](HashMap::with_hasher_in) method. |
343 | /// |
344 | /// [`HashDoS`]: https://en.wikipedia.org/wiki/Collision_attack |
345 | /// [`std::collections::hash_map::RandomState`]: https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html |
346 | /// |
347 | /// # Examples |
348 | /// |
349 | /// ``` |
350 | /// use hashbrown::HashMap; |
351 | /// use bumpalo::Bump; |
352 | /// |
353 | /// let bump = Bump::new(); |
354 | /// let mut map = HashMap::new_in(&bump); |
355 | /// |
356 | /// // The created HashMap holds none elements |
357 | /// assert_eq!(map.len(), 0); |
358 | /// |
359 | /// // The created HashMap also doesn't allocate memory |
360 | /// assert_eq!(map.capacity(), 0); |
361 | /// |
362 | /// // Now we insert element inside created HashMap |
363 | /// map.insert("One" , 1); |
364 | /// // We can see that the HashMap holds 1 element |
365 | /// assert_eq!(map.len(), 1); |
366 | /// // And it also allocates some capacity |
367 | /// assert!(map.capacity() > 1); |
368 | /// ``` |
369 | #[cfg_attr (feature = "inline-more" , inline)] |
370 | pub fn new_in(alloc: A) -> Self { |
371 | Self::with_hasher_in(DefaultHashBuilder::default(), alloc) |
372 | } |
373 | |
374 | /// Creates an empty `HashMap` with the specified capacity using the given allocator. |
375 | /// |
376 | /// The hash map will be able to hold at least `capacity` elements without |
377 | /// reallocating. If `capacity` is 0, the hash map will not allocate. |
378 | /// |
379 | /// # HashDoS resistance |
380 | /// |
381 | /// The `hash_builder` normally use a fixed key by default and that does |
382 | /// not allow the `HashMap` to be protected against attacks such as [`HashDoS`]. |
383 | /// Users who require HashDoS resistance should explicitly use |
384 | /// [`ahash::RandomState`] or [`std::collections::hash_map::RandomState`] |
385 | /// as the hasher when creating a [`HashMap`], for example with |
386 | /// [`with_capacity_and_hasher_in`](HashMap::with_capacity_and_hasher_in) method. |
387 | /// |
388 | /// [`HashDoS`]: https://en.wikipedia.org/wiki/Collision_attack |
389 | /// [`std::collections::hash_map::RandomState`]: https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html |
390 | /// |
391 | /// # Examples |
392 | /// |
393 | /// ``` |
394 | /// use hashbrown::HashMap; |
395 | /// use bumpalo::Bump; |
396 | /// |
397 | /// let bump = Bump::new(); |
398 | /// let mut map = HashMap::with_capacity_in(5, &bump); |
399 | /// |
400 | /// // The created HashMap holds none elements |
401 | /// assert_eq!(map.len(), 0); |
402 | /// // But it can hold at least 5 elements without reallocating |
403 | /// let empty_map_capacity = map.capacity(); |
404 | /// assert!(empty_map_capacity >= 5); |
405 | /// |
406 | /// // Now we insert some 5 elements inside created HashMap |
407 | /// map.insert("One" , 1); |
408 | /// map.insert("Two" , 2); |
409 | /// map.insert("Three" , 3); |
410 | /// map.insert("Four" , 4); |
411 | /// map.insert("Five" , 5); |
412 | /// |
413 | /// // We can see that the HashMap holds 5 elements |
414 | /// assert_eq!(map.len(), 5); |
415 | /// // But its capacity isn't changed |
416 | /// assert_eq!(map.capacity(), empty_map_capacity) |
417 | /// ``` |
418 | #[cfg_attr (feature = "inline-more" , inline)] |
419 | pub fn with_capacity_in(capacity: usize, alloc: A) -> Self { |
420 | Self::with_capacity_and_hasher_in(capacity, DefaultHashBuilder::default(), alloc) |
421 | } |
422 | } |
423 | |
424 | impl<K, V, S> HashMap<K, V, S> { |
425 | /// Creates an empty `HashMap` which will use the given hash builder to hash |
426 | /// keys. |
427 | /// |
428 | /// The hash map is initially created with a capacity of 0, so it will not |
429 | /// allocate until it is first inserted into. |
430 | /// |
431 | /// # HashDoS resistance |
432 | /// |
433 | /// The `hash_builder` normally use a fixed key by default and that does |
434 | /// not allow the `HashMap` to be protected against attacks such as [`HashDoS`]. |
435 | /// Users who require HashDoS resistance should explicitly use |
436 | /// [`ahash::RandomState`] or [`std::collections::hash_map::RandomState`] |
437 | /// as the hasher when creating a [`HashMap`]. |
438 | /// |
439 | /// The `hash_builder` passed should implement the [`BuildHasher`] trait for |
440 | /// the HashMap to be useful, see its documentation for details. |
441 | /// |
442 | /// [`HashDoS`]: https://en.wikipedia.org/wiki/Collision_attack |
443 | /// [`std::collections::hash_map::RandomState`]: https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html |
444 | /// [`BuildHasher`]: https://doc.rust-lang.org/std/hash/trait.BuildHasher.html |
445 | /// |
446 | /// # Examples |
447 | /// |
448 | /// ``` |
449 | /// use hashbrown::HashMap; |
450 | /// use hashbrown::hash_map::DefaultHashBuilder; |
451 | /// |
452 | /// let s = DefaultHashBuilder::default(); |
453 | /// let mut map = HashMap::with_hasher(s); |
454 | /// assert_eq!(map.len(), 0); |
455 | /// assert_eq!(map.capacity(), 0); |
456 | /// |
457 | /// map.insert(1, 2); |
458 | /// ``` |
459 | #[cfg_attr (feature = "inline-more" , inline)] |
460 | pub const fn with_hasher(hash_builder: S) -> Self { |
461 | Self { |
462 | hash_builder, |
463 | table: RawTable::new(), |
464 | } |
465 | } |
466 | |
467 | /// Creates an empty `HashMap` with the specified capacity, using `hash_builder` |
468 | /// to hash the keys. |
469 | /// |
470 | /// The hash map will be able to hold at least `capacity` elements without |
471 | /// reallocating. If `capacity` is 0, the hash map will not allocate. |
472 | /// |
473 | /// # HashDoS resistance |
474 | /// |
475 | /// The `hash_builder` normally use a fixed key by default and that does |
476 | /// not allow the `HashMap` to be protected against attacks such as [`HashDoS`]. |
477 | /// Users who require HashDoS resistance should explicitly use |
478 | /// [`ahash::RandomState`] or [`std::collections::hash_map::RandomState`] |
479 | /// as the hasher when creating a [`HashMap`]. |
480 | /// |
481 | /// The `hash_builder` passed should implement the [`BuildHasher`] trait for |
482 | /// the HashMap to be useful, see its documentation for details. |
483 | /// |
484 | /// [`HashDoS`]: https://en.wikipedia.org/wiki/Collision_attack |
485 | /// [`std::collections::hash_map::RandomState`]: https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html |
486 | /// [`BuildHasher`]: https://doc.rust-lang.org/std/hash/trait.BuildHasher.html |
487 | /// |
488 | /// # Examples |
489 | /// |
490 | /// ``` |
491 | /// use hashbrown::HashMap; |
492 | /// use hashbrown::hash_map::DefaultHashBuilder; |
493 | /// |
494 | /// let s = DefaultHashBuilder::default(); |
495 | /// let mut map = HashMap::with_capacity_and_hasher(10, s); |
496 | /// assert_eq!(map.len(), 0); |
497 | /// assert!(map.capacity() >= 10); |
498 | /// |
499 | /// map.insert(1, 2); |
500 | /// ``` |
501 | #[cfg_attr (feature = "inline-more" , inline)] |
502 | pub fn with_capacity_and_hasher(capacity: usize, hash_builder: S) -> Self { |
503 | Self { |
504 | hash_builder, |
505 | table: RawTable::with_capacity(capacity), |
506 | } |
507 | } |
508 | } |
509 | |
510 | impl<K, V, S, A: Allocator> HashMap<K, V, S, A> { |
511 | /// Returns a reference to the underlying allocator. |
512 | #[inline ] |
513 | pub fn allocator(&self) -> &A { |
514 | self.table.allocator() |
515 | } |
516 | |
517 | /// Creates an empty `HashMap` which will use the given hash builder to hash |
518 | /// keys. It will be allocated with the given allocator. |
519 | /// |
520 | /// The hash map is initially created with a capacity of 0, so it will not allocate until it |
521 | /// is first inserted into. |
522 | /// |
523 | /// # HashDoS resistance |
524 | /// |
525 | /// The `hash_builder` normally use a fixed key by default and that does |
526 | /// not allow the `HashMap` to be protected against attacks such as [`HashDoS`]. |
527 | /// Users who require HashDoS resistance should explicitly use |
528 | /// [`ahash::RandomState`] or [`std::collections::hash_map::RandomState`] |
529 | /// as the hasher when creating a [`HashMap`]. |
530 | /// |
531 | /// [`HashDoS`]: https://en.wikipedia.org/wiki/Collision_attack |
532 | /// [`std::collections::hash_map::RandomState`]: https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html |
533 | /// |
534 | /// # Examples |
535 | /// |
536 | /// ``` |
537 | /// use hashbrown::HashMap; |
538 | /// use hashbrown::hash_map::DefaultHashBuilder; |
539 | /// |
540 | /// let s = DefaultHashBuilder::default(); |
541 | /// let mut map = HashMap::with_hasher(s); |
542 | /// map.insert(1, 2); |
543 | /// ``` |
544 | #[cfg_attr (feature = "inline-more" , inline)] |
545 | pub const fn with_hasher_in(hash_builder: S, alloc: A) -> Self { |
546 | Self { |
547 | hash_builder, |
548 | table: RawTable::new_in(alloc), |
549 | } |
550 | } |
551 | |
552 | /// Creates an empty `HashMap` with the specified capacity, using `hash_builder` |
553 | /// to hash the keys. It will be allocated with the given allocator. |
554 | /// |
555 | /// The hash map will be able to hold at least `capacity` elements without |
556 | /// reallocating. If `capacity` is 0, the hash map will not allocate. |
557 | /// |
558 | /// # HashDoS resistance |
559 | /// |
560 | /// The `hash_builder` normally use a fixed key by default and that does |
561 | /// not allow the `HashMap` to be protected against attacks such as [`HashDoS`]. |
562 | /// Users who require HashDoS resistance should explicitly use |
563 | /// [`ahash::RandomState`] or [`std::collections::hash_map::RandomState`] |
564 | /// as the hasher when creating a [`HashMap`]. |
565 | /// |
566 | /// [`HashDoS`]: https://en.wikipedia.org/wiki/Collision_attack |
567 | /// [`std::collections::hash_map::RandomState`]: https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html |
568 | /// |
569 | /// # Examples |
570 | /// |
571 | /// ``` |
572 | /// use hashbrown::HashMap; |
573 | /// use hashbrown::hash_map::DefaultHashBuilder; |
574 | /// |
575 | /// let s = DefaultHashBuilder::default(); |
576 | /// let mut map = HashMap::with_capacity_and_hasher(10, s); |
577 | /// map.insert(1, 2); |
578 | /// ``` |
579 | #[cfg_attr (feature = "inline-more" , inline)] |
580 | pub fn with_capacity_and_hasher_in(capacity: usize, hash_builder: S, alloc: A) -> Self { |
581 | Self { |
582 | hash_builder, |
583 | table: RawTable::with_capacity_in(capacity, alloc), |
584 | } |
585 | } |
586 | |
587 | /// Returns a reference to the map's [`BuildHasher`]. |
588 | /// |
589 | /// [`BuildHasher`]: https://doc.rust-lang.org/std/hash/trait.BuildHasher.html |
590 | /// |
591 | /// # Examples |
592 | /// |
593 | /// ``` |
594 | /// use hashbrown::HashMap; |
595 | /// use hashbrown::hash_map::DefaultHashBuilder; |
596 | /// |
597 | /// let hasher = DefaultHashBuilder::default(); |
598 | /// let map: HashMap<i32, i32> = HashMap::with_hasher(hasher); |
599 | /// let hasher: &DefaultHashBuilder = map.hasher(); |
600 | /// ``` |
601 | #[cfg_attr (feature = "inline-more" , inline)] |
602 | pub fn hasher(&self) -> &S { |
603 | &self.hash_builder |
604 | } |
605 | |
606 | /// Returns the number of elements the map can hold without reallocating. |
607 | /// |
608 | /// This number is a lower bound; the `HashMap<K, V>` might be able to hold |
609 | /// more, but is guaranteed to be able to hold at least this many. |
610 | /// |
611 | /// # Examples |
612 | /// |
613 | /// ``` |
614 | /// use hashbrown::HashMap; |
615 | /// let map: HashMap<i32, i32> = HashMap::with_capacity(100); |
616 | /// assert_eq!(map.len(), 0); |
617 | /// assert!(map.capacity() >= 100); |
618 | /// ``` |
619 | #[cfg_attr (feature = "inline-more" , inline)] |
620 | pub fn capacity(&self) -> usize { |
621 | self.table.capacity() |
622 | } |
623 | |
624 | /// An iterator visiting all keys in arbitrary order. |
625 | /// The iterator element type is `&'a K`. |
626 | /// |
627 | /// # Examples |
628 | /// |
629 | /// ``` |
630 | /// use hashbrown::HashMap; |
631 | /// |
632 | /// let mut map = HashMap::new(); |
633 | /// map.insert("a" , 1); |
634 | /// map.insert("b" , 2); |
635 | /// map.insert("c" , 3); |
636 | /// assert_eq!(map.len(), 3); |
637 | /// let mut vec: Vec<&str> = Vec::new(); |
638 | /// |
639 | /// for key in map.keys() { |
640 | /// println!("{}" , key); |
641 | /// vec.push(*key); |
642 | /// } |
643 | /// |
644 | /// // The `Keys` iterator produces keys in arbitrary order, so the |
645 | /// // keys must be sorted to test them against a sorted array. |
646 | /// vec.sort_unstable(); |
647 | /// assert_eq!(vec, ["a" , "b" , "c" ]); |
648 | /// |
649 | /// assert_eq!(map.len(), 3); |
650 | /// ``` |
651 | #[cfg_attr (feature = "inline-more" , inline)] |
652 | pub fn keys(&self) -> Keys<'_, K, V> { |
653 | Keys { inner: self.iter() } |
654 | } |
655 | |
656 | /// An iterator visiting all values in arbitrary order. |
657 | /// The iterator element type is `&'a V`. |
658 | /// |
659 | /// # Examples |
660 | /// |
661 | /// ``` |
662 | /// use hashbrown::HashMap; |
663 | /// |
664 | /// let mut map = HashMap::new(); |
665 | /// map.insert("a" , 1); |
666 | /// map.insert("b" , 2); |
667 | /// map.insert("c" , 3); |
668 | /// assert_eq!(map.len(), 3); |
669 | /// let mut vec: Vec<i32> = Vec::new(); |
670 | /// |
671 | /// for val in map.values() { |
672 | /// println!("{}" , val); |
673 | /// vec.push(*val); |
674 | /// } |
675 | /// |
676 | /// // The `Values` iterator produces values in arbitrary order, so the |
677 | /// // values must be sorted to test them against a sorted array. |
678 | /// vec.sort_unstable(); |
679 | /// assert_eq!(vec, [1, 2, 3]); |
680 | /// |
681 | /// assert_eq!(map.len(), 3); |
682 | /// ``` |
683 | #[cfg_attr (feature = "inline-more" , inline)] |
684 | pub fn values(&self) -> Values<'_, K, V> { |
685 | Values { inner: self.iter() } |
686 | } |
687 | |
688 | /// An iterator visiting all values mutably in arbitrary order. |
689 | /// The iterator element type is `&'a mut V`. |
690 | /// |
691 | /// # Examples |
692 | /// |
693 | /// ``` |
694 | /// use hashbrown::HashMap; |
695 | /// |
696 | /// let mut map = HashMap::new(); |
697 | /// |
698 | /// map.insert("a" , 1); |
699 | /// map.insert("b" , 2); |
700 | /// map.insert("c" , 3); |
701 | /// |
702 | /// for val in map.values_mut() { |
703 | /// *val = *val + 10; |
704 | /// } |
705 | /// |
706 | /// assert_eq!(map.len(), 3); |
707 | /// let mut vec: Vec<i32> = Vec::new(); |
708 | /// |
709 | /// for val in map.values() { |
710 | /// println!("{}" , val); |
711 | /// vec.push(*val); |
712 | /// } |
713 | /// |
714 | /// // The `Values` iterator produces values in arbitrary order, so the |
715 | /// // values must be sorted to test them against a sorted array. |
716 | /// vec.sort_unstable(); |
717 | /// assert_eq!(vec, [11, 12, 13]); |
718 | /// |
719 | /// assert_eq!(map.len(), 3); |
720 | /// ``` |
721 | #[cfg_attr (feature = "inline-more" , inline)] |
722 | pub fn values_mut(&mut self) -> ValuesMut<'_, K, V> { |
723 | ValuesMut { |
724 | inner: self.iter_mut(), |
725 | } |
726 | } |
727 | |
728 | /// An iterator visiting all key-value pairs in arbitrary order. |
729 | /// The iterator element type is `(&'a K, &'a V)`. |
730 | /// |
731 | /// # Examples |
732 | /// |
733 | /// ``` |
734 | /// use hashbrown::HashMap; |
735 | /// |
736 | /// let mut map = HashMap::new(); |
737 | /// map.insert("a" , 1); |
738 | /// map.insert("b" , 2); |
739 | /// map.insert("c" , 3); |
740 | /// assert_eq!(map.len(), 3); |
741 | /// let mut vec: Vec<(&str, i32)> = Vec::new(); |
742 | /// |
743 | /// for (key, val) in map.iter() { |
744 | /// println!("key: {} val: {}" , key, val); |
745 | /// vec.push((*key, *val)); |
746 | /// } |
747 | /// |
748 | /// // The `Iter` iterator produces items in arbitrary order, so the |
749 | /// // items must be sorted to test them against a sorted array. |
750 | /// vec.sort_unstable(); |
751 | /// assert_eq!(vec, [("a" , 1), ("b" , 2), ("c" , 3)]); |
752 | /// |
753 | /// assert_eq!(map.len(), 3); |
754 | /// ``` |
755 | #[cfg_attr (feature = "inline-more" , inline)] |
756 | pub fn iter(&self) -> Iter<'_, K, V> { |
757 | // Here we tie the lifetime of self to the iter. |
758 | unsafe { |
759 | Iter { |
760 | inner: self.table.iter(), |
761 | marker: PhantomData, |
762 | } |
763 | } |
764 | } |
765 | |
766 | /// An iterator visiting all key-value pairs in arbitrary order, |
767 | /// with mutable references to the values. |
768 | /// The iterator element type is `(&'a K, &'a mut V)`. |
769 | /// |
770 | /// # Examples |
771 | /// |
772 | /// ``` |
773 | /// use hashbrown::HashMap; |
774 | /// |
775 | /// let mut map = HashMap::new(); |
776 | /// map.insert("a" , 1); |
777 | /// map.insert("b" , 2); |
778 | /// map.insert("c" , 3); |
779 | /// |
780 | /// // Update all values |
781 | /// for (_, val) in map.iter_mut() { |
782 | /// *val *= 2; |
783 | /// } |
784 | /// |
785 | /// assert_eq!(map.len(), 3); |
786 | /// let mut vec: Vec<(&str, i32)> = Vec::new(); |
787 | /// |
788 | /// for (key, val) in &map { |
789 | /// println!("key: {} val: {}" , key, val); |
790 | /// vec.push((*key, *val)); |
791 | /// } |
792 | /// |
793 | /// // The `Iter` iterator produces items in arbitrary order, so the |
794 | /// // items must be sorted to test them against a sorted array. |
795 | /// vec.sort_unstable(); |
796 | /// assert_eq!(vec, [("a" , 2), ("b" , 4), ("c" , 6)]); |
797 | /// |
798 | /// assert_eq!(map.len(), 3); |
799 | /// ``` |
800 | #[cfg_attr (feature = "inline-more" , inline)] |
801 | pub fn iter_mut(&mut self) -> IterMut<'_, K, V> { |
802 | // Here we tie the lifetime of self to the iter. |
803 | unsafe { |
804 | IterMut { |
805 | inner: self.table.iter(), |
806 | marker: PhantomData, |
807 | } |
808 | } |
809 | } |
810 | |
811 | #[cfg (test)] |
812 | #[cfg_attr (feature = "inline-more" , inline)] |
813 | fn raw_capacity(&self) -> usize { |
814 | self.table.buckets() |
815 | } |
816 | |
817 | /// Returns the number of elements in the map. |
818 | /// |
819 | /// # Examples |
820 | /// |
821 | /// ``` |
822 | /// use hashbrown::HashMap; |
823 | /// |
824 | /// let mut a = HashMap::new(); |
825 | /// assert_eq!(a.len(), 0); |
826 | /// a.insert(1, "a" ); |
827 | /// assert_eq!(a.len(), 1); |
828 | /// ``` |
829 | #[cfg_attr (feature = "inline-more" , inline)] |
830 | pub fn len(&self) -> usize { |
831 | self.table.len() |
832 | } |
833 | |
834 | /// Returns `true` if the map contains no elements. |
835 | /// |
836 | /// # Examples |
837 | /// |
838 | /// ``` |
839 | /// use hashbrown::HashMap; |
840 | /// |
841 | /// let mut a = HashMap::new(); |
842 | /// assert!(a.is_empty()); |
843 | /// a.insert(1, "a" ); |
844 | /// assert!(!a.is_empty()); |
845 | /// ``` |
846 | #[cfg_attr (feature = "inline-more" , inline)] |
847 | pub fn is_empty(&self) -> bool { |
848 | self.len() == 0 |
849 | } |
850 | |
851 | /// Clears the map, returning all key-value pairs as an iterator. Keeps the |
852 | /// allocated memory for reuse. |
853 | /// |
854 | /// If the returned iterator is dropped before being fully consumed, it |
855 | /// drops the remaining key-value pairs. The returned iterator keeps a |
856 | /// mutable borrow on the vector to optimize its implementation. |
857 | /// |
858 | /// # Examples |
859 | /// |
860 | /// ``` |
861 | /// use hashbrown::HashMap; |
862 | /// |
863 | /// let mut a = HashMap::new(); |
864 | /// a.insert(1, "a" ); |
865 | /// a.insert(2, "b" ); |
866 | /// let capacity_before_drain = a.capacity(); |
867 | /// |
868 | /// for (k, v) in a.drain().take(1) { |
869 | /// assert!(k == 1 || k == 2); |
870 | /// assert!(v == "a" || v == "b" ); |
871 | /// } |
872 | /// |
873 | /// // As we can see, the map is empty and contains no element. |
874 | /// assert!(a.is_empty() && a.len() == 0); |
875 | /// // But map capacity is equal to old one. |
876 | /// assert_eq!(a.capacity(), capacity_before_drain); |
877 | /// |
878 | /// let mut a = HashMap::new(); |
879 | /// a.insert(1, "a" ); |
880 | /// a.insert(2, "b" ); |
881 | /// |
882 | /// { // Iterator is dropped without being consumed. |
883 | /// let d = a.drain(); |
884 | /// } |
885 | /// |
886 | /// // But the map is empty even if we do not use Drain iterator. |
887 | /// assert!(a.is_empty()); |
888 | /// ``` |
889 | #[cfg_attr (feature = "inline-more" , inline)] |
890 | pub fn drain(&mut self) -> Drain<'_, K, V, A> { |
891 | Drain { |
892 | inner: self.table.drain(), |
893 | } |
894 | } |
895 | |
896 | /// Retains only the elements specified by the predicate. Keeps the |
897 | /// allocated memory for reuse. |
898 | /// |
899 | /// In other words, remove all pairs `(k, v)` such that `f(&k, &mut v)` returns `false`. |
900 | /// The elements are visited in unsorted (and unspecified) order. |
901 | /// |
902 | /// # Examples |
903 | /// |
904 | /// ``` |
905 | /// use hashbrown::HashMap; |
906 | /// |
907 | /// let mut map: HashMap<i32, i32> = (0..8).map(|x|(x, x*10)).collect(); |
908 | /// assert_eq!(map.len(), 8); |
909 | /// |
910 | /// map.retain(|&k, _| k % 2 == 0); |
911 | /// |
912 | /// // We can see, that the number of elements inside map is changed. |
913 | /// assert_eq!(map.len(), 4); |
914 | /// |
915 | /// let mut vec: Vec<(i32, i32)> = map.iter().map(|(&k, &v)| (k, v)).collect(); |
916 | /// vec.sort_unstable(); |
917 | /// assert_eq!(vec, [(0, 0), (2, 20), (4, 40), (6, 60)]); |
918 | /// ``` |
919 | pub fn retain<F>(&mut self, mut f: F) |
920 | where |
921 | F: FnMut(&K, &mut V) -> bool, |
922 | { |
923 | // Here we only use `iter` as a temporary, preventing use-after-free |
924 | unsafe { |
925 | for item in self.table.iter() { |
926 | let &mut (ref key, ref mut value) = item.as_mut(); |
927 | if !f(key, value) { |
928 | self.table.erase(item); |
929 | } |
930 | } |
931 | } |
932 | } |
933 | |
934 | /// Drains elements which are true under the given predicate, |
935 | /// and returns an iterator over the removed items. |
936 | /// |
937 | /// In other words, move all pairs `(k, v)` such that `f(&k, &mut v)` returns `true` out |
938 | /// into another iterator. |
939 | /// |
940 | /// Note that `extract_if` lets you mutate every value in the filter closure, regardless of |
941 | /// whether you choose to keep or remove it. |
942 | /// |
943 | /// If the returned `ExtractIf` is not exhausted, e.g. because it is dropped without iterating |
944 | /// or the iteration short-circuits, then the remaining elements will be retained. |
945 | /// Use [`retain()`] with a negated predicate if you do not need the returned iterator. |
946 | /// |
947 | /// Keeps the allocated memory for reuse. |
948 | /// |
949 | /// [`retain()`]: HashMap::retain |
950 | /// |
951 | /// # Examples |
952 | /// |
953 | /// ``` |
954 | /// use hashbrown::HashMap; |
955 | /// |
956 | /// let mut map: HashMap<i32, i32> = (0..8).map(|x| (x, x)).collect(); |
957 | /// |
958 | /// let drained: HashMap<i32, i32> = map.extract_if(|k, _v| k % 2 == 0).collect(); |
959 | /// |
960 | /// let mut evens = drained.keys().cloned().collect::<Vec<_>>(); |
961 | /// let mut odds = map.keys().cloned().collect::<Vec<_>>(); |
962 | /// evens.sort(); |
963 | /// odds.sort(); |
964 | /// |
965 | /// assert_eq!(evens, vec![0, 2, 4, 6]); |
966 | /// assert_eq!(odds, vec![1, 3, 5, 7]); |
967 | /// |
968 | /// let mut map: HashMap<i32, i32> = (0..8).map(|x| (x, x)).collect(); |
969 | /// |
970 | /// { // Iterator is dropped without being consumed. |
971 | /// let d = map.extract_if(|k, _v| k % 2 != 0); |
972 | /// } |
973 | /// |
974 | /// // ExtractIf was not exhausted, therefore no elements were drained. |
975 | /// assert_eq!(map.len(), 8); |
976 | /// ``` |
977 | #[cfg_attr (feature = "inline-more" , inline)] |
978 | pub fn extract_if<F>(&mut self, f: F) -> ExtractIf<'_, K, V, F, A> |
979 | where |
980 | F: FnMut(&K, &mut V) -> bool, |
981 | { |
982 | ExtractIf { |
983 | f, |
984 | inner: RawExtractIf { |
985 | iter: unsafe { self.table.iter() }, |
986 | table: &mut self.table, |
987 | }, |
988 | } |
989 | } |
990 | |
991 | /// Clears the map, removing all key-value pairs. Keeps the allocated memory |
992 | /// for reuse. |
993 | /// |
994 | /// # Examples |
995 | /// |
996 | /// ``` |
997 | /// use hashbrown::HashMap; |
998 | /// |
999 | /// let mut a = HashMap::new(); |
1000 | /// a.insert(1, "a" ); |
1001 | /// let capacity_before_clear = a.capacity(); |
1002 | /// |
1003 | /// a.clear(); |
1004 | /// |
1005 | /// // Map is empty. |
1006 | /// assert!(a.is_empty()); |
1007 | /// // But map capacity is equal to old one. |
1008 | /// assert_eq!(a.capacity(), capacity_before_clear); |
1009 | /// ``` |
1010 | #[cfg_attr (feature = "inline-more" , inline)] |
1011 | pub fn clear(&mut self) { |
1012 | self.table.clear(); |
1013 | } |
1014 | |
1015 | /// Creates a consuming iterator visiting all the keys in arbitrary order. |
1016 | /// The map cannot be used after calling this. |
1017 | /// The iterator element type is `K`. |
1018 | /// |
1019 | /// # Examples |
1020 | /// |
1021 | /// ``` |
1022 | /// use hashbrown::HashMap; |
1023 | /// |
1024 | /// let mut map = HashMap::new(); |
1025 | /// map.insert("a" , 1); |
1026 | /// map.insert("b" , 2); |
1027 | /// map.insert("c" , 3); |
1028 | /// |
1029 | /// let mut vec: Vec<&str> = map.into_keys().collect(); |
1030 | /// |
1031 | /// // The `IntoKeys` iterator produces keys in arbitrary order, so the |
1032 | /// // keys must be sorted to test them against a sorted array. |
1033 | /// vec.sort_unstable(); |
1034 | /// assert_eq!(vec, ["a" , "b" , "c" ]); |
1035 | /// ``` |
1036 | #[inline ] |
1037 | pub fn into_keys(self) -> IntoKeys<K, V, A> { |
1038 | IntoKeys { |
1039 | inner: self.into_iter(), |
1040 | } |
1041 | } |
1042 | |
1043 | /// Creates a consuming iterator visiting all the values in arbitrary order. |
1044 | /// The map cannot be used after calling this. |
1045 | /// The iterator element type is `V`. |
1046 | /// |
1047 | /// # Examples |
1048 | /// |
1049 | /// ``` |
1050 | /// use hashbrown::HashMap; |
1051 | /// |
1052 | /// let mut map = HashMap::new(); |
1053 | /// map.insert("a" , 1); |
1054 | /// map.insert("b" , 2); |
1055 | /// map.insert("c" , 3); |
1056 | /// |
1057 | /// let mut vec: Vec<i32> = map.into_values().collect(); |
1058 | /// |
1059 | /// // The `IntoValues` iterator produces values in arbitrary order, so |
1060 | /// // the values must be sorted to test them against a sorted array. |
1061 | /// vec.sort_unstable(); |
1062 | /// assert_eq!(vec, [1, 2, 3]); |
1063 | /// ``` |
1064 | #[inline ] |
1065 | pub fn into_values(self) -> IntoValues<K, V, A> { |
1066 | IntoValues { |
1067 | inner: self.into_iter(), |
1068 | } |
1069 | } |
1070 | } |
1071 | |
1072 | impl<K, V, S, A> HashMap<K, V, S, A> |
1073 | where |
1074 | K: Eq + Hash, |
1075 | S: BuildHasher, |
1076 | A: Allocator, |
1077 | { |
1078 | /// Reserves capacity for at least `additional` more elements to be inserted |
1079 | /// in the `HashMap`. The collection may reserve more space to avoid |
1080 | /// frequent reallocations. |
1081 | /// |
1082 | /// # Panics |
1083 | /// |
1084 | /// Panics if the new capacity exceeds [`isize::MAX`] bytes and [`abort`] the program |
1085 | /// in case of allocation error. Use [`try_reserve`](HashMap::try_reserve) instead |
1086 | /// if you want to handle memory allocation failure. |
1087 | /// |
1088 | /// [`isize::MAX`]: https://doc.rust-lang.org/std/primitive.isize.html |
1089 | /// [`abort`]: https://doc.rust-lang.org/alloc/alloc/fn.handle_alloc_error.html |
1090 | /// |
1091 | /// # Examples |
1092 | /// |
1093 | /// ``` |
1094 | /// use hashbrown::HashMap; |
1095 | /// let mut map: HashMap<&str, i32> = HashMap::new(); |
1096 | /// // Map is empty and doesn't allocate memory |
1097 | /// assert_eq!(map.capacity(), 0); |
1098 | /// |
1099 | /// map.reserve(10); |
1100 | /// |
1101 | /// // And now map can hold at least 10 elements |
1102 | /// assert!(map.capacity() >= 10); |
1103 | /// ``` |
1104 | #[cfg_attr (feature = "inline-more" , inline)] |
1105 | pub fn reserve(&mut self, additional: usize) { |
1106 | self.table |
1107 | .reserve(additional, make_hasher::<_, V, S>(&self.hash_builder)); |
1108 | } |
1109 | |
1110 | /// Tries to reserve capacity for at least `additional` more elements to be inserted |
1111 | /// in the given `HashMap<K,V>`. The collection may reserve more space to avoid |
1112 | /// frequent reallocations. |
1113 | /// |
1114 | /// # Errors |
1115 | /// |
1116 | /// If the capacity overflows, or the allocator reports a failure, then an error |
1117 | /// is returned. |
1118 | /// |
1119 | /// # Examples |
1120 | /// |
1121 | /// ``` |
1122 | /// use hashbrown::HashMap; |
1123 | /// |
1124 | /// let mut map: HashMap<&str, isize> = HashMap::new(); |
1125 | /// // Map is empty and doesn't allocate memory |
1126 | /// assert_eq!(map.capacity(), 0); |
1127 | /// |
1128 | /// map.try_reserve(10).expect("why is the test harness OOMing on 10 bytes?" ); |
1129 | /// |
1130 | /// // And now map can hold at least 10 elements |
1131 | /// assert!(map.capacity() >= 10); |
1132 | /// ``` |
1133 | /// If the capacity overflows, or the allocator reports a failure, then an error |
1134 | /// is returned: |
1135 | /// ``` |
1136 | /// # fn test() { |
1137 | /// use hashbrown::HashMap; |
1138 | /// use hashbrown::TryReserveError; |
1139 | /// let mut map: HashMap<i32, i32> = HashMap::new(); |
1140 | /// |
1141 | /// match map.try_reserve(usize::MAX) { |
1142 | /// Err(error) => match error { |
1143 | /// TryReserveError::CapacityOverflow => {} |
1144 | /// _ => panic!("TryReserveError::AllocError ?" ), |
1145 | /// }, |
1146 | /// _ => panic!(), |
1147 | /// } |
1148 | /// # } |
1149 | /// # fn main() { |
1150 | /// # #[cfg (not(miri))] |
1151 | /// # test() |
1152 | /// # } |
1153 | /// ``` |
1154 | #[cfg_attr (feature = "inline-more" , inline)] |
1155 | pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> { |
1156 | self.table |
1157 | .try_reserve(additional, make_hasher::<_, V, S>(&self.hash_builder)) |
1158 | } |
1159 | |
1160 | /// Shrinks the capacity of the map as much as possible. It will drop |
1161 | /// down as much as possible while maintaining the internal rules |
1162 | /// and possibly leaving some space in accordance with the resize policy. |
1163 | /// |
1164 | /// # Examples |
1165 | /// |
1166 | /// ``` |
1167 | /// use hashbrown::HashMap; |
1168 | /// |
1169 | /// let mut map: HashMap<i32, i32> = HashMap::with_capacity(100); |
1170 | /// map.insert(1, 2); |
1171 | /// map.insert(3, 4); |
1172 | /// assert!(map.capacity() >= 100); |
1173 | /// map.shrink_to_fit(); |
1174 | /// assert!(map.capacity() >= 2); |
1175 | /// ``` |
1176 | #[cfg_attr (feature = "inline-more" , inline)] |
1177 | pub fn shrink_to_fit(&mut self) { |
1178 | self.table |
1179 | .shrink_to(0, make_hasher::<_, V, S>(&self.hash_builder)); |
1180 | } |
1181 | |
1182 | /// Shrinks the capacity of the map with a lower limit. It will drop |
1183 | /// down no lower than the supplied limit while maintaining the internal rules |
1184 | /// and possibly leaving some space in accordance with the resize policy. |
1185 | /// |
1186 | /// This function does nothing if the current capacity is smaller than the |
1187 | /// supplied minimum capacity. |
1188 | /// |
1189 | /// # Examples |
1190 | /// |
1191 | /// ``` |
1192 | /// use hashbrown::HashMap; |
1193 | /// |
1194 | /// let mut map: HashMap<i32, i32> = HashMap::with_capacity(100); |
1195 | /// map.insert(1, 2); |
1196 | /// map.insert(3, 4); |
1197 | /// assert!(map.capacity() >= 100); |
1198 | /// map.shrink_to(10); |
1199 | /// assert!(map.capacity() >= 10); |
1200 | /// map.shrink_to(0); |
1201 | /// assert!(map.capacity() >= 2); |
1202 | /// map.shrink_to(10); |
1203 | /// assert!(map.capacity() >= 2); |
1204 | /// ``` |
1205 | #[cfg_attr (feature = "inline-more" , inline)] |
1206 | pub fn shrink_to(&mut self, min_capacity: usize) { |
1207 | self.table |
1208 | .shrink_to(min_capacity, make_hasher::<_, V, S>(&self.hash_builder)); |
1209 | } |
1210 | |
1211 | /// Gets the given key's corresponding entry in the map for in-place manipulation. |
1212 | /// |
1213 | /// # Examples |
1214 | /// |
1215 | /// ``` |
1216 | /// use hashbrown::HashMap; |
1217 | /// |
1218 | /// let mut letters = HashMap::new(); |
1219 | /// |
1220 | /// for ch in "a short treatise on fungi" .chars() { |
1221 | /// let counter = letters.entry(ch).or_insert(0); |
1222 | /// *counter += 1; |
1223 | /// } |
1224 | /// |
1225 | /// assert_eq!(letters[&'s' ], 2); |
1226 | /// assert_eq!(letters[&'t' ], 3); |
1227 | /// assert_eq!(letters[&'u' ], 1); |
1228 | /// assert_eq!(letters.get(&'y' ), None); |
1229 | /// ``` |
1230 | #[cfg_attr (feature = "inline-more" , inline)] |
1231 | pub fn entry(&mut self, key: K) -> Entry<'_, K, V, S, A> { |
1232 | let hash = make_hash::<K, S>(&self.hash_builder, &key); |
1233 | if let Some(elem) = self.table.find(hash, equivalent_key(&key)) { |
1234 | Entry::Occupied(OccupiedEntry { |
1235 | hash, |
1236 | key: Some(key), |
1237 | elem, |
1238 | table: self, |
1239 | }) |
1240 | } else { |
1241 | Entry::Vacant(VacantEntry { |
1242 | hash, |
1243 | key, |
1244 | table: self, |
1245 | }) |
1246 | } |
1247 | } |
1248 | |
1249 | /// Gets the given key's corresponding entry by reference in the map for in-place manipulation. |
1250 | /// |
1251 | /// # Examples |
1252 | /// |
1253 | /// ``` |
1254 | /// use hashbrown::HashMap; |
1255 | /// |
1256 | /// let mut words: HashMap<String, usize> = HashMap::new(); |
1257 | /// let source = ["poneyland" , "horseyland" , "poneyland" , "poneyland" ]; |
1258 | /// for (i, &s) in source.iter().enumerate() { |
1259 | /// let counter = words.entry_ref(s).or_insert(0); |
1260 | /// *counter += 1; |
1261 | /// } |
1262 | /// |
1263 | /// assert_eq!(words["poneyland" ], 3); |
1264 | /// assert_eq!(words["horseyland" ], 1); |
1265 | /// ``` |
1266 | #[cfg_attr (feature = "inline-more" , inline)] |
1267 | pub fn entry_ref<'a, 'b, Q: ?Sized>(&'a mut self, key: &'b Q) -> EntryRef<'a, 'b, K, Q, V, S, A> |
1268 | where |
1269 | Q: Hash + Equivalent<K>, |
1270 | { |
1271 | let hash = make_hash::<Q, S>(&self.hash_builder, key); |
1272 | if let Some(elem) = self.table.find(hash, equivalent_key(key)) { |
1273 | EntryRef::Occupied(OccupiedEntryRef { |
1274 | hash, |
1275 | key: Some(KeyOrRef::Borrowed(key)), |
1276 | elem, |
1277 | table: self, |
1278 | }) |
1279 | } else { |
1280 | EntryRef::Vacant(VacantEntryRef { |
1281 | hash, |
1282 | key: KeyOrRef::Borrowed(key), |
1283 | table: self, |
1284 | }) |
1285 | } |
1286 | } |
1287 | |
1288 | /// Returns a reference to the value corresponding to the key. |
1289 | /// |
1290 | /// The key may be any borrowed form of the map's key type, but |
1291 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
1292 | /// the key type. |
1293 | /// |
1294 | /// [`Eq`]: https://doc.rust-lang.org/std/cmp/trait.Eq.html |
1295 | /// [`Hash`]: https://doc.rust-lang.org/std/hash/trait.Hash.html |
1296 | /// |
1297 | /// # Examples |
1298 | /// |
1299 | /// ``` |
1300 | /// use hashbrown::HashMap; |
1301 | /// |
1302 | /// let mut map = HashMap::new(); |
1303 | /// map.insert(1, "a" ); |
1304 | /// assert_eq!(map.get(&1), Some(&"a" )); |
1305 | /// assert_eq!(map.get(&2), None); |
1306 | /// ``` |
1307 | #[inline ] |
1308 | pub fn get<Q: ?Sized>(&self, k: &Q) -> Option<&V> |
1309 | where |
1310 | Q: Hash + Equivalent<K>, |
1311 | { |
1312 | // Avoid `Option::map` because it bloats LLVM IR. |
1313 | match self.get_inner(k) { |
1314 | Some((_, v)) => Some(v), |
1315 | None => None, |
1316 | } |
1317 | } |
1318 | |
1319 | /// Returns the key-value pair corresponding to the supplied key. |
1320 | /// |
1321 | /// The supplied key may be any borrowed form of the map's key type, but |
1322 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
1323 | /// the key type. |
1324 | /// |
1325 | /// [`Eq`]: https://doc.rust-lang.org/std/cmp/trait.Eq.html |
1326 | /// [`Hash`]: https://doc.rust-lang.org/std/hash/trait.Hash.html |
1327 | /// |
1328 | /// # Examples |
1329 | /// |
1330 | /// ``` |
1331 | /// use hashbrown::HashMap; |
1332 | /// |
1333 | /// let mut map = HashMap::new(); |
1334 | /// map.insert(1, "a" ); |
1335 | /// assert_eq!(map.get_key_value(&1), Some((&1, &"a" ))); |
1336 | /// assert_eq!(map.get_key_value(&2), None); |
1337 | /// ``` |
1338 | #[inline ] |
1339 | pub fn get_key_value<Q: ?Sized>(&self, k: &Q) -> Option<(&K, &V)> |
1340 | where |
1341 | Q: Hash + Equivalent<K>, |
1342 | { |
1343 | // Avoid `Option::map` because it bloats LLVM IR. |
1344 | match self.get_inner(k) { |
1345 | Some((key, value)) => Some((key, value)), |
1346 | None => None, |
1347 | } |
1348 | } |
1349 | |
1350 | #[inline ] |
1351 | fn get_inner<Q: ?Sized>(&self, k: &Q) -> Option<&(K, V)> |
1352 | where |
1353 | Q: Hash + Equivalent<K>, |
1354 | { |
1355 | if self.table.is_empty() { |
1356 | None |
1357 | } else { |
1358 | let hash = make_hash::<Q, S>(&self.hash_builder, k); |
1359 | self.table.get(hash, equivalent_key(k)) |
1360 | } |
1361 | } |
1362 | |
1363 | /// Returns the key-value pair corresponding to the supplied key, with a mutable reference to value. |
1364 | /// |
1365 | /// The supplied key may be any borrowed form of the map's key type, but |
1366 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
1367 | /// the key type. |
1368 | /// |
1369 | /// [`Eq`]: https://doc.rust-lang.org/std/cmp/trait.Eq.html |
1370 | /// [`Hash`]: https://doc.rust-lang.org/std/hash/trait.Hash.html |
1371 | /// |
1372 | /// # Examples |
1373 | /// |
1374 | /// ``` |
1375 | /// use hashbrown::HashMap; |
1376 | /// |
1377 | /// let mut map = HashMap::new(); |
1378 | /// map.insert(1, "a" ); |
1379 | /// let (k, v) = map.get_key_value_mut(&1).unwrap(); |
1380 | /// assert_eq!(k, &1); |
1381 | /// assert_eq!(v, &mut "a" ); |
1382 | /// *v = "b" ; |
1383 | /// assert_eq!(map.get_key_value_mut(&1), Some((&1, &mut "b" ))); |
1384 | /// assert_eq!(map.get_key_value_mut(&2), None); |
1385 | /// ``` |
1386 | #[inline ] |
1387 | pub fn get_key_value_mut<Q: ?Sized>(&mut self, k: &Q) -> Option<(&K, &mut V)> |
1388 | where |
1389 | Q: Hash + Equivalent<K>, |
1390 | { |
1391 | // Avoid `Option::map` because it bloats LLVM IR. |
1392 | match self.get_inner_mut(k) { |
1393 | Some(&mut (ref key, ref mut value)) => Some((key, value)), |
1394 | None => None, |
1395 | } |
1396 | } |
1397 | |
1398 | /// Returns `true` if the map contains a value for the specified key. |
1399 | /// |
1400 | /// The key may be any borrowed form of the map's key type, but |
1401 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
1402 | /// the key type. |
1403 | /// |
1404 | /// [`Eq`]: https://doc.rust-lang.org/std/cmp/trait.Eq.html |
1405 | /// [`Hash`]: https://doc.rust-lang.org/std/hash/trait.Hash.html |
1406 | /// |
1407 | /// # Examples |
1408 | /// |
1409 | /// ``` |
1410 | /// use hashbrown::HashMap; |
1411 | /// |
1412 | /// let mut map = HashMap::new(); |
1413 | /// map.insert(1, "a" ); |
1414 | /// assert_eq!(map.contains_key(&1), true); |
1415 | /// assert_eq!(map.contains_key(&2), false); |
1416 | /// ``` |
1417 | #[cfg_attr (feature = "inline-more" , inline)] |
1418 | pub fn contains_key<Q: ?Sized>(&self, k: &Q) -> bool |
1419 | where |
1420 | Q: Hash + Equivalent<K>, |
1421 | { |
1422 | self.get_inner(k).is_some() |
1423 | } |
1424 | |
1425 | /// Returns a mutable reference to the value corresponding to the key. |
1426 | /// |
1427 | /// The key may be any borrowed form of the map's key type, but |
1428 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
1429 | /// the key type. |
1430 | /// |
1431 | /// [`Eq`]: https://doc.rust-lang.org/std/cmp/trait.Eq.html |
1432 | /// [`Hash`]: https://doc.rust-lang.org/std/hash/trait.Hash.html |
1433 | /// |
1434 | /// # Examples |
1435 | /// |
1436 | /// ``` |
1437 | /// use hashbrown::HashMap; |
1438 | /// |
1439 | /// let mut map = HashMap::new(); |
1440 | /// map.insert(1, "a" ); |
1441 | /// if let Some(x) = map.get_mut(&1) { |
1442 | /// *x = "b" ; |
1443 | /// } |
1444 | /// assert_eq!(map[&1], "b" ); |
1445 | /// |
1446 | /// assert_eq!(map.get_mut(&2), None); |
1447 | /// ``` |
1448 | #[cfg_attr (feature = "inline-more" , inline)] |
1449 | pub fn get_mut<Q: ?Sized>(&mut self, k: &Q) -> Option<&mut V> |
1450 | where |
1451 | Q: Hash + Equivalent<K>, |
1452 | { |
1453 | // Avoid `Option::map` because it bloats LLVM IR. |
1454 | match self.get_inner_mut(k) { |
1455 | Some(&mut (_, ref mut v)) => Some(v), |
1456 | None => None, |
1457 | } |
1458 | } |
1459 | |
1460 | #[inline ] |
1461 | fn get_inner_mut<Q: ?Sized>(&mut self, k: &Q) -> Option<&mut (K, V)> |
1462 | where |
1463 | Q: Hash + Equivalent<K>, |
1464 | { |
1465 | if self.table.is_empty() { |
1466 | None |
1467 | } else { |
1468 | let hash = make_hash::<Q, S>(&self.hash_builder, k); |
1469 | self.table.get_mut(hash, equivalent_key(k)) |
1470 | } |
1471 | } |
1472 | |
1473 | /// Attempts to get mutable references to `N` values in the map at once. |
1474 | /// |
1475 | /// Returns an array of length `N` with the results of each query. For soundness, at most one |
1476 | /// mutable reference will be returned to any value. `None` will be returned if any of the |
1477 | /// keys are duplicates or missing. |
1478 | /// |
1479 | /// # Examples |
1480 | /// |
1481 | /// ``` |
1482 | /// use hashbrown::HashMap; |
1483 | /// |
1484 | /// let mut libraries = HashMap::new(); |
1485 | /// libraries.insert("Bodleian Library" .to_string(), 1602); |
1486 | /// libraries.insert("Athenæum" .to_string(), 1807); |
1487 | /// libraries.insert("Herzogin-Anna-Amalia-Bibliothek" .to_string(), 1691); |
1488 | /// libraries.insert("Library of Congress" .to_string(), 1800); |
1489 | /// |
1490 | /// let got = libraries.get_many_mut([ |
1491 | /// "Athenæum" , |
1492 | /// "Library of Congress" , |
1493 | /// ]); |
1494 | /// assert_eq!( |
1495 | /// got, |
1496 | /// Some([ |
1497 | /// &mut 1807, |
1498 | /// &mut 1800, |
1499 | /// ]), |
1500 | /// ); |
1501 | /// |
1502 | /// // Missing keys result in None |
1503 | /// let got = libraries.get_many_mut([ |
1504 | /// "Athenæum" , |
1505 | /// "New York Public Library" , |
1506 | /// ]); |
1507 | /// assert_eq!(got, None); |
1508 | /// |
1509 | /// // Duplicate keys result in None |
1510 | /// let got = libraries.get_many_mut([ |
1511 | /// "Athenæum" , |
1512 | /// "Athenæum" , |
1513 | /// ]); |
1514 | /// assert_eq!(got, None); |
1515 | /// ``` |
1516 | pub fn get_many_mut<Q: ?Sized, const N: usize>(&mut self, ks: [&Q; N]) -> Option<[&'_ mut V; N]> |
1517 | where |
1518 | Q: Hash + Equivalent<K>, |
1519 | { |
1520 | self.get_many_mut_inner(ks).map(|res| res.map(|(_, v)| v)) |
1521 | } |
1522 | |
1523 | /// Attempts to get mutable references to `N` values in the map at once, without validating that |
1524 | /// the values are unique. |
1525 | /// |
1526 | /// Returns an array of length `N` with the results of each query. `None` will be returned if |
1527 | /// any of the keys are missing. |
1528 | /// |
1529 | /// For a safe alternative see [`get_many_mut`](`HashMap::get_many_mut`). |
1530 | /// |
1531 | /// # Safety |
1532 | /// |
1533 | /// Calling this method with overlapping keys is *[undefined behavior]* even if the resulting |
1534 | /// references are not used. |
1535 | /// |
1536 | /// [undefined behavior]: https://doc.rust-lang.org/reference/behavior-considered-undefined.html |
1537 | /// |
1538 | /// # Examples |
1539 | /// |
1540 | /// ``` |
1541 | /// use hashbrown::HashMap; |
1542 | /// |
1543 | /// let mut libraries = HashMap::new(); |
1544 | /// libraries.insert("Bodleian Library" .to_string(), 1602); |
1545 | /// libraries.insert("Athenæum" .to_string(), 1807); |
1546 | /// libraries.insert("Herzogin-Anna-Amalia-Bibliothek" .to_string(), 1691); |
1547 | /// libraries.insert("Library of Congress" .to_string(), 1800); |
1548 | /// |
1549 | /// let got = libraries.get_many_mut([ |
1550 | /// "Athenæum" , |
1551 | /// "Library of Congress" , |
1552 | /// ]); |
1553 | /// assert_eq!( |
1554 | /// got, |
1555 | /// Some([ |
1556 | /// &mut 1807, |
1557 | /// &mut 1800, |
1558 | /// ]), |
1559 | /// ); |
1560 | /// |
1561 | /// // Missing keys result in None |
1562 | /// let got = libraries.get_many_mut([ |
1563 | /// "Athenæum" , |
1564 | /// "New York Public Library" , |
1565 | /// ]); |
1566 | /// assert_eq!(got, None); |
1567 | /// ``` |
1568 | pub unsafe fn get_many_unchecked_mut<Q: ?Sized, const N: usize>( |
1569 | &mut self, |
1570 | ks: [&Q; N], |
1571 | ) -> Option<[&'_ mut V; N]> |
1572 | where |
1573 | Q: Hash + Equivalent<K>, |
1574 | { |
1575 | self.get_many_unchecked_mut_inner(ks) |
1576 | .map(|res| res.map(|(_, v)| v)) |
1577 | } |
1578 | |
1579 | /// Attempts to get mutable references to `N` values in the map at once, with immutable |
1580 | /// references to the corresponding keys. |
1581 | /// |
1582 | /// Returns an array of length `N` with the results of each query. For soundness, at most one |
1583 | /// mutable reference will be returned to any value. `None` will be returned if any of the keys |
1584 | /// are duplicates or missing. |
1585 | /// |
1586 | /// # Examples |
1587 | /// |
1588 | /// ``` |
1589 | /// use hashbrown::HashMap; |
1590 | /// |
1591 | /// let mut libraries = HashMap::new(); |
1592 | /// libraries.insert("Bodleian Library" .to_string(), 1602); |
1593 | /// libraries.insert("Athenæum" .to_string(), 1807); |
1594 | /// libraries.insert("Herzogin-Anna-Amalia-Bibliothek" .to_string(), 1691); |
1595 | /// libraries.insert("Library of Congress" .to_string(), 1800); |
1596 | /// |
1597 | /// let got = libraries.get_many_key_value_mut([ |
1598 | /// "Bodleian Library" , |
1599 | /// "Herzogin-Anna-Amalia-Bibliothek" , |
1600 | /// ]); |
1601 | /// assert_eq!( |
1602 | /// got, |
1603 | /// Some([ |
1604 | /// (&"Bodleian Library" .to_string(), &mut 1602), |
1605 | /// (&"Herzogin-Anna-Amalia-Bibliothek" .to_string(), &mut 1691), |
1606 | /// ]), |
1607 | /// ); |
1608 | /// // Missing keys result in None |
1609 | /// let got = libraries.get_many_key_value_mut([ |
1610 | /// "Bodleian Library" , |
1611 | /// "Gewandhaus" , |
1612 | /// ]); |
1613 | /// assert_eq!(got, None); |
1614 | /// |
1615 | /// // Duplicate keys result in None |
1616 | /// let got = libraries.get_many_key_value_mut([ |
1617 | /// "Bodleian Library" , |
1618 | /// "Herzogin-Anna-Amalia-Bibliothek" , |
1619 | /// "Herzogin-Anna-Amalia-Bibliothek" , |
1620 | /// ]); |
1621 | /// assert_eq!(got, None); |
1622 | /// ``` |
1623 | pub fn get_many_key_value_mut<Q: ?Sized, const N: usize>( |
1624 | &mut self, |
1625 | ks: [&Q; N], |
1626 | ) -> Option<[(&'_ K, &'_ mut V); N]> |
1627 | where |
1628 | Q: Hash + Equivalent<K>, |
1629 | { |
1630 | self.get_many_mut_inner(ks) |
1631 | .map(|res| res.map(|(k, v)| (&*k, v))) |
1632 | } |
1633 | |
1634 | /// Attempts to get mutable references to `N` values in the map at once, with immutable |
1635 | /// references to the corresponding keys, without validating that the values are unique. |
1636 | /// |
1637 | /// Returns an array of length `N` with the results of each query. `None` will be returned if |
1638 | /// any of the keys are missing. |
1639 | /// |
1640 | /// For a safe alternative see [`get_many_key_value_mut`](`HashMap::get_many_key_value_mut`). |
1641 | /// |
1642 | /// # Safety |
1643 | /// |
1644 | /// Calling this method with overlapping keys is *[undefined behavior]* even if the resulting |
1645 | /// references are not used. |
1646 | /// |
1647 | /// [undefined behavior]: https://doc.rust-lang.org/reference/behavior-considered-undefined.html |
1648 | /// |
1649 | /// # Examples |
1650 | /// |
1651 | /// ``` |
1652 | /// use hashbrown::HashMap; |
1653 | /// |
1654 | /// let mut libraries = HashMap::new(); |
1655 | /// libraries.insert("Bodleian Library" .to_string(), 1602); |
1656 | /// libraries.insert("Athenæum" .to_string(), 1807); |
1657 | /// libraries.insert("Herzogin-Anna-Amalia-Bibliothek" .to_string(), 1691); |
1658 | /// libraries.insert("Library of Congress" .to_string(), 1800); |
1659 | /// |
1660 | /// let got = libraries.get_many_key_value_mut([ |
1661 | /// "Bodleian Library" , |
1662 | /// "Herzogin-Anna-Amalia-Bibliothek" , |
1663 | /// ]); |
1664 | /// assert_eq!( |
1665 | /// got, |
1666 | /// Some([ |
1667 | /// (&"Bodleian Library" .to_string(), &mut 1602), |
1668 | /// (&"Herzogin-Anna-Amalia-Bibliothek" .to_string(), &mut 1691), |
1669 | /// ]), |
1670 | /// ); |
1671 | /// // Missing keys result in None |
1672 | /// let got = libraries.get_many_key_value_mut([ |
1673 | /// "Bodleian Library" , |
1674 | /// "Gewandhaus" , |
1675 | /// ]); |
1676 | /// assert_eq!(got, None); |
1677 | /// ``` |
1678 | pub unsafe fn get_many_key_value_unchecked_mut<Q: ?Sized, const N: usize>( |
1679 | &mut self, |
1680 | ks: [&Q; N], |
1681 | ) -> Option<[(&'_ K, &'_ mut V); N]> |
1682 | where |
1683 | Q: Hash + Equivalent<K>, |
1684 | { |
1685 | self.get_many_unchecked_mut_inner(ks) |
1686 | .map(|res| res.map(|(k, v)| (&*k, v))) |
1687 | } |
1688 | |
1689 | fn get_many_mut_inner<Q: ?Sized, const N: usize>( |
1690 | &mut self, |
1691 | ks: [&Q; N], |
1692 | ) -> Option<[&'_ mut (K, V); N]> |
1693 | where |
1694 | Q: Hash + Equivalent<K>, |
1695 | { |
1696 | let hashes = self.build_hashes_inner(ks); |
1697 | self.table |
1698 | .get_many_mut(hashes, |i, (k, _)| ks[i].equivalent(k)) |
1699 | } |
1700 | |
1701 | unsafe fn get_many_unchecked_mut_inner<Q: ?Sized, const N: usize>( |
1702 | &mut self, |
1703 | ks: [&Q; N], |
1704 | ) -> Option<[&'_ mut (K, V); N]> |
1705 | where |
1706 | Q: Hash + Equivalent<K>, |
1707 | { |
1708 | let hashes = self.build_hashes_inner(ks); |
1709 | self.table |
1710 | .get_many_unchecked_mut(hashes, |i, (k, _)| ks[i].equivalent(k)) |
1711 | } |
1712 | |
1713 | fn build_hashes_inner<Q: ?Sized, const N: usize>(&self, ks: [&Q; N]) -> [u64; N] |
1714 | where |
1715 | Q: Hash + Equivalent<K>, |
1716 | { |
1717 | let mut hashes = [0_u64; N]; |
1718 | for i in 0..N { |
1719 | hashes[i] = make_hash::<Q, S>(&self.hash_builder, ks[i]); |
1720 | } |
1721 | hashes |
1722 | } |
1723 | |
1724 | /// Inserts a key-value pair into the map. |
1725 | /// |
1726 | /// If the map did not have this key present, [`None`] is returned. |
1727 | /// |
1728 | /// If the map did have this key present, the value is updated, and the old |
1729 | /// value is returned. The key is not updated, though; this matters for |
1730 | /// types that can be `==` without being identical. See the [`std::collections`] |
1731 | /// [module-level documentation] for more. |
1732 | /// |
1733 | /// [`None`]: https://doc.rust-lang.org/std/option/enum.Option.html#variant.None |
1734 | /// [`std::collections`]: https://doc.rust-lang.org/std/collections/index.html |
1735 | /// [module-level documentation]: https://doc.rust-lang.org/std/collections/index.html#insert-and-complex-keys |
1736 | /// |
1737 | /// # Examples |
1738 | /// |
1739 | /// ``` |
1740 | /// use hashbrown::HashMap; |
1741 | /// |
1742 | /// let mut map = HashMap::new(); |
1743 | /// assert_eq!(map.insert(37, "a" ), None); |
1744 | /// assert_eq!(map.is_empty(), false); |
1745 | /// |
1746 | /// map.insert(37, "b" ); |
1747 | /// assert_eq!(map.insert(37, "c" ), Some("b" )); |
1748 | /// assert_eq!(map[&37], "c" ); |
1749 | /// ``` |
1750 | #[cfg_attr (feature = "inline-more" , inline)] |
1751 | pub fn insert(&mut self, k: K, v: V) -> Option<V> { |
1752 | let hash = make_hash::<K, S>(&self.hash_builder, &k); |
1753 | let hasher = make_hasher::<_, V, S>(&self.hash_builder); |
1754 | match self |
1755 | .table |
1756 | .find_or_find_insert_slot(hash, equivalent_key(&k), hasher) |
1757 | { |
1758 | Ok(bucket) => Some(mem::replace(unsafe { &mut bucket.as_mut().1 }, v)), |
1759 | Err(slot) => { |
1760 | unsafe { |
1761 | self.table.insert_in_slot(hash, slot, (k, v)); |
1762 | } |
1763 | None |
1764 | } |
1765 | } |
1766 | } |
1767 | |
1768 | /// Insert a key-value pair into the map without checking |
1769 | /// if the key already exists in the map. |
1770 | /// |
1771 | /// Returns a reference to the key and value just inserted. |
1772 | /// |
1773 | /// This operation is safe if a key does not exist in the map. |
1774 | /// |
1775 | /// However, if a key exists in the map already, the behavior is unspecified: |
1776 | /// this operation may panic, loop forever, or any following operation with the map |
1777 | /// may panic, loop forever or return arbitrary result. |
1778 | /// |
1779 | /// That said, this operation (and following operations) are guaranteed to |
1780 | /// not violate memory safety. |
1781 | /// |
1782 | /// This operation is faster than regular insert, because it does not perform |
1783 | /// lookup before insertion. |
1784 | /// |
1785 | /// This operation is useful during initial population of the map. |
1786 | /// For example, when constructing a map from another map, we know |
1787 | /// that keys are unique. |
1788 | /// |
1789 | /// # Examples |
1790 | /// |
1791 | /// ``` |
1792 | /// use hashbrown::HashMap; |
1793 | /// |
1794 | /// let mut map1 = HashMap::new(); |
1795 | /// assert_eq!(map1.insert(1, "a" ), None); |
1796 | /// assert_eq!(map1.insert(2, "b" ), None); |
1797 | /// assert_eq!(map1.insert(3, "c" ), None); |
1798 | /// assert_eq!(map1.len(), 3); |
1799 | /// |
1800 | /// let mut map2 = HashMap::new(); |
1801 | /// |
1802 | /// for (key, value) in map1.into_iter() { |
1803 | /// map2.insert_unique_unchecked(key, value); |
1804 | /// } |
1805 | /// |
1806 | /// let (key, value) = map2.insert_unique_unchecked(4, "d" ); |
1807 | /// assert_eq!(key, &4); |
1808 | /// assert_eq!(value, &mut "d" ); |
1809 | /// *value = "e" ; |
1810 | /// |
1811 | /// assert_eq!(map2[&1], "a" ); |
1812 | /// assert_eq!(map2[&2], "b" ); |
1813 | /// assert_eq!(map2[&3], "c" ); |
1814 | /// assert_eq!(map2[&4], "e" ); |
1815 | /// assert_eq!(map2.len(), 4); |
1816 | /// ``` |
1817 | #[cfg_attr (feature = "inline-more" , inline)] |
1818 | pub fn insert_unique_unchecked(&mut self, k: K, v: V) -> (&K, &mut V) { |
1819 | let hash = make_hash::<K, S>(&self.hash_builder, &k); |
1820 | let bucket = self |
1821 | .table |
1822 | .insert(hash, (k, v), make_hasher::<_, V, S>(&self.hash_builder)); |
1823 | let (k_ref, v_ref) = unsafe { bucket.as_mut() }; |
1824 | (k_ref, v_ref) |
1825 | } |
1826 | |
1827 | /// Tries to insert a key-value pair into the map, and returns |
1828 | /// a mutable reference to the value in the entry. |
1829 | /// |
1830 | /// # Errors |
1831 | /// |
1832 | /// If the map already had this key present, nothing is updated, and |
1833 | /// an error containing the occupied entry and the value is returned. |
1834 | /// |
1835 | /// # Examples |
1836 | /// |
1837 | /// Basic usage: |
1838 | /// |
1839 | /// ``` |
1840 | /// use hashbrown::HashMap; |
1841 | /// use hashbrown::hash_map::OccupiedError; |
1842 | /// |
1843 | /// let mut map = HashMap::new(); |
1844 | /// assert_eq!(map.try_insert(37, "a" ).unwrap(), &"a" ); |
1845 | /// |
1846 | /// match map.try_insert(37, "b" ) { |
1847 | /// Err(OccupiedError { entry, value }) => { |
1848 | /// assert_eq!(entry.key(), &37); |
1849 | /// assert_eq!(entry.get(), &"a" ); |
1850 | /// assert_eq!(value, "b" ); |
1851 | /// } |
1852 | /// _ => panic!() |
1853 | /// } |
1854 | /// ``` |
1855 | #[cfg_attr (feature = "inline-more" , inline)] |
1856 | pub fn try_insert( |
1857 | &mut self, |
1858 | key: K, |
1859 | value: V, |
1860 | ) -> Result<&mut V, OccupiedError<'_, K, V, S, A>> { |
1861 | match self.entry(key) { |
1862 | Entry::Occupied(entry) => Err(OccupiedError { entry, value }), |
1863 | Entry::Vacant(entry) => Ok(entry.insert(value)), |
1864 | } |
1865 | } |
1866 | |
1867 | /// Removes a key from the map, returning the value at the key if the key |
1868 | /// was previously in the map. Keeps the allocated memory for reuse. |
1869 | /// |
1870 | /// The key may be any borrowed form of the map's key type, but |
1871 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
1872 | /// the key type. |
1873 | /// |
1874 | /// [`Eq`]: https://doc.rust-lang.org/std/cmp/trait.Eq.html |
1875 | /// [`Hash`]: https://doc.rust-lang.org/std/hash/trait.Hash.html |
1876 | /// |
1877 | /// # Examples |
1878 | /// |
1879 | /// ``` |
1880 | /// use hashbrown::HashMap; |
1881 | /// |
1882 | /// let mut map = HashMap::new(); |
1883 | /// // The map is empty |
1884 | /// assert!(map.is_empty() && map.capacity() == 0); |
1885 | /// |
1886 | /// map.insert(1, "a" ); |
1887 | /// |
1888 | /// assert_eq!(map.remove(&1), Some("a" )); |
1889 | /// assert_eq!(map.remove(&1), None); |
1890 | /// |
1891 | /// // Now map holds none elements |
1892 | /// assert!(map.is_empty()); |
1893 | /// ``` |
1894 | #[cfg_attr (feature = "inline-more" , inline)] |
1895 | pub fn remove<Q: ?Sized>(&mut self, k: &Q) -> Option<V> |
1896 | where |
1897 | Q: Hash + Equivalent<K>, |
1898 | { |
1899 | // Avoid `Option::map` because it bloats LLVM IR. |
1900 | match self.remove_entry(k) { |
1901 | Some((_, v)) => Some(v), |
1902 | None => None, |
1903 | } |
1904 | } |
1905 | |
1906 | /// Removes a key from the map, returning the stored key and value if the |
1907 | /// key was previously in the map. Keeps the allocated memory for reuse. |
1908 | /// |
1909 | /// The key may be any borrowed form of the map's key type, but |
1910 | /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for |
1911 | /// the key type. |
1912 | /// |
1913 | /// [`Eq`]: https://doc.rust-lang.org/std/cmp/trait.Eq.html |
1914 | /// [`Hash`]: https://doc.rust-lang.org/std/hash/trait.Hash.html |
1915 | /// |
1916 | /// # Examples |
1917 | /// |
1918 | /// ``` |
1919 | /// use hashbrown::HashMap; |
1920 | /// |
1921 | /// let mut map = HashMap::new(); |
1922 | /// // The map is empty |
1923 | /// assert!(map.is_empty() && map.capacity() == 0); |
1924 | /// |
1925 | /// map.insert(1, "a" ); |
1926 | /// |
1927 | /// assert_eq!(map.remove_entry(&1), Some((1, "a" ))); |
1928 | /// assert_eq!(map.remove(&1), None); |
1929 | /// |
1930 | /// // Now map hold none elements |
1931 | /// assert!(map.is_empty()); |
1932 | /// ``` |
1933 | #[cfg_attr (feature = "inline-more" , inline)] |
1934 | pub fn remove_entry<Q: ?Sized>(&mut self, k: &Q) -> Option<(K, V)> |
1935 | where |
1936 | Q: Hash + Equivalent<K>, |
1937 | { |
1938 | let hash = make_hash::<Q, S>(&self.hash_builder, k); |
1939 | self.table.remove_entry(hash, equivalent_key(k)) |
1940 | } |
1941 | } |
1942 | |
1943 | impl<K, V, S, A: Allocator> HashMap<K, V, S, A> { |
1944 | /// Creates a raw entry builder for the HashMap. |
1945 | /// |
1946 | /// Raw entries provide the lowest level of control for searching and |
1947 | /// manipulating a map. They must be manually initialized with a hash and |
1948 | /// then manually searched. After this, insertions into a vacant entry |
1949 | /// still require an owned key to be provided. |
1950 | /// |
1951 | /// Raw entries are useful for such exotic situations as: |
1952 | /// |
1953 | /// * Hash memoization |
1954 | /// * Deferring the creation of an owned key until it is known to be required |
1955 | /// * Using a search key that doesn't work with the Borrow trait |
1956 | /// * Using custom comparison logic without newtype wrappers |
1957 | /// |
1958 | /// Because raw entries provide much more low-level control, it's much easier |
1959 | /// to put the HashMap into an inconsistent state which, while memory-safe, |
1960 | /// will cause the map to produce seemingly random results. Higher-level and |
1961 | /// more foolproof APIs like `entry` should be preferred when possible. |
1962 | /// |
1963 | /// In particular, the hash used to initialized the raw entry must still be |
1964 | /// consistent with the hash of the key that is ultimately stored in the entry. |
1965 | /// This is because implementations of HashMap may need to recompute hashes |
1966 | /// when resizing, at which point only the keys are available. |
1967 | /// |
1968 | /// Raw entries give mutable access to the keys. This must not be used |
1969 | /// to modify how the key would compare or hash, as the map will not re-evaluate |
1970 | /// where the key should go, meaning the keys may become "lost" if their |
1971 | /// location does not reflect their state. For instance, if you change a key |
1972 | /// so that the map now contains keys which compare equal, search may start |
1973 | /// acting erratically, with two keys randomly masking each other. Implementations |
1974 | /// are free to assume this doesn't happen (within the limits of memory-safety). |
1975 | /// |
1976 | /// # Examples |
1977 | /// |
1978 | /// ``` |
1979 | /// use core::hash::{BuildHasher, Hash}; |
1980 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
1981 | /// |
1982 | /// let mut map = HashMap::new(); |
1983 | /// map.extend([("a" , 100), ("b" , 200), ("c" , 300)]); |
1984 | /// |
1985 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
1986 | /// use core::hash::Hasher; |
1987 | /// let mut state = hash_builder.build_hasher(); |
1988 | /// key.hash(&mut state); |
1989 | /// state.finish() |
1990 | /// } |
1991 | /// |
1992 | /// // Existing key (insert and update) |
1993 | /// match map.raw_entry_mut().from_key(&"a" ) { |
1994 | /// RawEntryMut::Vacant(_) => unreachable!(), |
1995 | /// RawEntryMut::Occupied(mut view) => { |
1996 | /// assert_eq!(view.get(), &100); |
1997 | /// let v = view.get_mut(); |
1998 | /// let new_v = (*v) * 10; |
1999 | /// *v = new_v; |
2000 | /// assert_eq!(view.insert(1111), 1000); |
2001 | /// } |
2002 | /// } |
2003 | /// |
2004 | /// assert_eq!(map[&"a" ], 1111); |
2005 | /// assert_eq!(map.len(), 3); |
2006 | /// |
2007 | /// // Existing key (take) |
2008 | /// let hash = compute_hash(map.hasher(), &"c" ); |
2009 | /// match map.raw_entry_mut().from_key_hashed_nocheck(hash, &"c" ) { |
2010 | /// RawEntryMut::Vacant(_) => unreachable!(), |
2011 | /// RawEntryMut::Occupied(view) => { |
2012 | /// assert_eq!(view.remove_entry(), ("c" , 300)); |
2013 | /// } |
2014 | /// } |
2015 | /// assert_eq!(map.raw_entry().from_key(&"c" ), None); |
2016 | /// assert_eq!(map.len(), 2); |
2017 | /// |
2018 | /// // Nonexistent key (insert and update) |
2019 | /// let key = "d" ; |
2020 | /// let hash = compute_hash(map.hasher(), &key); |
2021 | /// match map.raw_entry_mut().from_hash(hash, |q| *q == key) { |
2022 | /// RawEntryMut::Occupied(_) => unreachable!(), |
2023 | /// RawEntryMut::Vacant(view) => { |
2024 | /// let (k, value) = view.insert("d" , 4000); |
2025 | /// assert_eq!((*k, *value), ("d" , 4000)); |
2026 | /// *value = 40000; |
2027 | /// } |
2028 | /// } |
2029 | /// assert_eq!(map[&"d" ], 40000); |
2030 | /// assert_eq!(map.len(), 3); |
2031 | /// |
2032 | /// match map.raw_entry_mut().from_hash(hash, |q| *q == key) { |
2033 | /// RawEntryMut::Vacant(_) => unreachable!(), |
2034 | /// RawEntryMut::Occupied(view) => { |
2035 | /// assert_eq!(view.remove_entry(), ("d" , 40000)); |
2036 | /// } |
2037 | /// } |
2038 | /// assert_eq!(map.get(&"d" ), None); |
2039 | /// assert_eq!(map.len(), 2); |
2040 | /// ``` |
2041 | #[cfg_attr (feature = "inline-more" , inline)] |
2042 | pub fn raw_entry_mut(&mut self) -> RawEntryBuilderMut<'_, K, V, S, A> { |
2043 | RawEntryBuilderMut { map: self } |
2044 | } |
2045 | |
2046 | /// Creates a raw immutable entry builder for the HashMap. |
2047 | /// |
2048 | /// Raw entries provide the lowest level of control for searching and |
2049 | /// manipulating a map. They must be manually initialized with a hash and |
2050 | /// then manually searched. |
2051 | /// |
2052 | /// This is useful for |
2053 | /// * Hash memoization |
2054 | /// * Using a search key that doesn't work with the Borrow trait |
2055 | /// * Using custom comparison logic without newtype wrappers |
2056 | /// |
2057 | /// Unless you are in such a situation, higher-level and more foolproof APIs like |
2058 | /// `get` should be preferred. |
2059 | /// |
2060 | /// Immutable raw entries have very limited use; you might instead want `raw_entry_mut`. |
2061 | /// |
2062 | /// # Examples |
2063 | /// |
2064 | /// ``` |
2065 | /// use core::hash::{BuildHasher, Hash}; |
2066 | /// use hashbrown::HashMap; |
2067 | /// |
2068 | /// let mut map = HashMap::new(); |
2069 | /// map.extend([("a" , 100), ("b" , 200), ("c" , 300)]); |
2070 | /// |
2071 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
2072 | /// use core::hash::Hasher; |
2073 | /// let mut state = hash_builder.build_hasher(); |
2074 | /// key.hash(&mut state); |
2075 | /// state.finish() |
2076 | /// } |
2077 | /// |
2078 | /// for k in ["a" , "b" , "c" , "d" , "e" , "f" ] { |
2079 | /// let hash = compute_hash(map.hasher(), k); |
2080 | /// let v = map.get(&k).cloned(); |
2081 | /// let kv = v.as_ref().map(|v| (&k, v)); |
2082 | /// |
2083 | /// println!("Key: {} and value: {:?}" , k, v); |
2084 | /// |
2085 | /// assert_eq!(map.raw_entry().from_key(&k), kv); |
2086 | /// assert_eq!(map.raw_entry().from_hash(hash, |q| *q == k), kv); |
2087 | /// assert_eq!(map.raw_entry().from_key_hashed_nocheck(hash, &k), kv); |
2088 | /// } |
2089 | /// ``` |
2090 | #[cfg_attr (feature = "inline-more" , inline)] |
2091 | pub fn raw_entry(&self) -> RawEntryBuilder<'_, K, V, S, A> { |
2092 | RawEntryBuilder { map: self } |
2093 | } |
2094 | |
2095 | /// Returns a reference to the [`RawTable`] used underneath [`HashMap`]. |
2096 | /// This function is only available if the `raw` feature of the crate is enabled. |
2097 | /// |
2098 | /// See [`raw_table_mut`] for more. |
2099 | /// |
2100 | /// [`raw_table_mut`]: Self::raw_table_mut |
2101 | #[cfg (feature = "raw" )] |
2102 | #[cfg_attr (feature = "inline-more" , inline)] |
2103 | pub fn raw_table(&self) -> &RawTable<(K, V), A> { |
2104 | &self.table |
2105 | } |
2106 | |
2107 | /// Returns a mutable reference to the [`RawTable`] used underneath [`HashMap`]. |
2108 | /// This function is only available if the `raw` feature of the crate is enabled. |
2109 | /// |
2110 | /// # Note |
2111 | /// |
2112 | /// Calling this function is safe, but using the raw hash table API may require |
2113 | /// unsafe functions or blocks. |
2114 | /// |
2115 | /// `RawTable` API gives the lowest level of control under the map that can be useful |
2116 | /// for extending the HashMap's API, but may lead to *[undefined behavior]*. |
2117 | /// |
2118 | /// [`HashMap`]: struct.HashMap.html |
2119 | /// [`RawTable`]: crate::raw::RawTable |
2120 | /// [undefined behavior]: https://doc.rust-lang.org/reference/behavior-considered-undefined.html |
2121 | /// |
2122 | /// # Examples |
2123 | /// |
2124 | /// ``` |
2125 | /// use core::hash::{BuildHasher, Hash}; |
2126 | /// use hashbrown::HashMap; |
2127 | /// |
2128 | /// let mut map = HashMap::new(); |
2129 | /// map.extend([("a" , 10), ("b" , 20), ("c" , 30)]); |
2130 | /// assert_eq!(map.len(), 3); |
2131 | /// |
2132 | /// // Let's imagine that we have a value and a hash of the key, but not the key itself. |
2133 | /// // However, if you want to remove the value from the map by hash and value, and you |
2134 | /// // know exactly that the value is unique, then you can create a function like this: |
2135 | /// fn remove_by_hash<K, V, S, F>( |
2136 | /// map: &mut HashMap<K, V, S>, |
2137 | /// hash: u64, |
2138 | /// is_match: F, |
2139 | /// ) -> Option<(K, V)> |
2140 | /// where |
2141 | /// F: Fn(&(K, V)) -> bool, |
2142 | /// { |
2143 | /// let raw_table = map.raw_table_mut(); |
2144 | /// match raw_table.find(hash, is_match) { |
2145 | /// Some(bucket) => Some(unsafe { raw_table.remove(bucket).0 }), |
2146 | /// None => None, |
2147 | /// } |
2148 | /// } |
2149 | /// |
2150 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
2151 | /// use core::hash::Hasher; |
2152 | /// let mut state = hash_builder.build_hasher(); |
2153 | /// key.hash(&mut state); |
2154 | /// state.finish() |
2155 | /// } |
2156 | /// |
2157 | /// let hash = compute_hash(map.hasher(), "a" ); |
2158 | /// assert_eq!(remove_by_hash(&mut map, hash, |(_, v)| *v == 10), Some(("a" , 10))); |
2159 | /// assert_eq!(map.get(&"a" ), None); |
2160 | /// assert_eq!(map.len(), 2); |
2161 | /// ``` |
2162 | #[cfg (feature = "raw" )] |
2163 | #[cfg_attr (feature = "inline-more" , inline)] |
2164 | pub fn raw_table_mut(&mut self) -> &mut RawTable<(K, V), A> { |
2165 | &mut self.table |
2166 | } |
2167 | } |
2168 | |
2169 | impl<K, V, S, A> PartialEq for HashMap<K, V, S, A> |
2170 | where |
2171 | K: Eq + Hash, |
2172 | V: PartialEq, |
2173 | S: BuildHasher, |
2174 | A: Allocator, |
2175 | { |
2176 | fn eq(&self, other: &Self) -> bool { |
2177 | if self.len() != other.len() { |
2178 | return false; |
2179 | } |
2180 | |
2181 | self.iter() |
2182 | .all(|(key: &{unknown}, value)| other.get(key).map_or(false, |v| *value == *v)) |
2183 | } |
2184 | } |
2185 | |
2186 | impl<K, V, S, A> Eq for HashMap<K, V, S, A> |
2187 | where |
2188 | K: Eq + Hash, |
2189 | V: Eq, |
2190 | S: BuildHasher, |
2191 | A: Allocator, |
2192 | { |
2193 | } |
2194 | |
2195 | impl<K, V, S, A> Debug for HashMap<K, V, S, A> |
2196 | where |
2197 | K: Debug, |
2198 | V: Debug, |
2199 | A: Allocator, |
2200 | { |
2201 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
2202 | f.debug_map().entries(self.iter()).finish() |
2203 | } |
2204 | } |
2205 | |
2206 | impl<K, V, S, A> Default for HashMap<K, V, S, A> |
2207 | where |
2208 | S: Default, |
2209 | A: Default + Allocator, |
2210 | { |
2211 | /// Creates an empty `HashMap<K, V, S, A>`, with the `Default` value for the hasher and allocator. |
2212 | /// |
2213 | /// # Examples |
2214 | /// |
2215 | /// ``` |
2216 | /// use hashbrown::HashMap; |
2217 | /// use std::collections::hash_map::RandomState; |
2218 | /// |
2219 | /// // You can specify all types of HashMap, including hasher and allocator. |
2220 | /// // Created map is empty and don't allocate memory |
2221 | /// let map: HashMap<u32, String> = Default::default(); |
2222 | /// assert_eq!(map.capacity(), 0); |
2223 | /// let map: HashMap<u32, String, RandomState> = HashMap::default(); |
2224 | /// assert_eq!(map.capacity(), 0); |
2225 | /// ``` |
2226 | #[cfg_attr (feature = "inline-more" , inline)] |
2227 | fn default() -> Self { |
2228 | Self::with_hasher_in(hash_builder:Default::default(), alloc:Default::default()) |
2229 | } |
2230 | } |
2231 | |
2232 | impl<K, Q: ?Sized, V, S, A> Index<&Q> for HashMap<K, V, S, A> |
2233 | where |
2234 | K: Eq + Hash, |
2235 | Q: Hash + Equivalent<K>, |
2236 | S: BuildHasher, |
2237 | A: Allocator, |
2238 | { |
2239 | type Output = V; |
2240 | |
2241 | /// Returns a reference to the value corresponding to the supplied key. |
2242 | /// |
2243 | /// # Panics |
2244 | /// |
2245 | /// Panics if the key is not present in the `HashMap`. |
2246 | /// |
2247 | /// # Examples |
2248 | /// |
2249 | /// ``` |
2250 | /// use hashbrown::HashMap; |
2251 | /// |
2252 | /// let map: HashMap<_, _> = [("a" , "One" ), ("b" , "Two" )].into(); |
2253 | /// |
2254 | /// assert_eq!(map[&"a" ], "One" ); |
2255 | /// assert_eq!(map[&"b" ], "Two" ); |
2256 | /// ``` |
2257 | #[cfg_attr (feature = "inline-more" , inline)] |
2258 | fn index(&self, key: &Q) -> &V { |
2259 | self.get(key).expect("no entry found for key" ) |
2260 | } |
2261 | } |
2262 | |
2263 | // The default hasher is used to match the std implementation signature |
2264 | #[cfg (feature = "ahash" )] |
2265 | impl<K, V, A, const N: usize> From<[(K, V); N]> for HashMap<K, V, DefaultHashBuilder, A> |
2266 | where |
2267 | K: Eq + Hash, |
2268 | A: Default + Allocator, |
2269 | { |
2270 | /// # Examples |
2271 | /// |
2272 | /// ``` |
2273 | /// use hashbrown::HashMap; |
2274 | /// |
2275 | /// let map1 = HashMap::from([(1, 2), (3, 4)]); |
2276 | /// let map2: HashMap<_, _> = [(1, 2), (3, 4)].into(); |
2277 | /// assert_eq!(map1, map2); |
2278 | /// ``` |
2279 | fn from(arr: [(K, V); N]) -> Self { |
2280 | arr.into_iter().collect() |
2281 | } |
2282 | } |
2283 | |
2284 | /// An iterator over the entries of a `HashMap` in arbitrary order. |
2285 | /// The iterator element type is `(&'a K, &'a V)`. |
2286 | /// |
2287 | /// This `struct` is created by the [`iter`] method on [`HashMap`]. See its |
2288 | /// documentation for more. |
2289 | /// |
2290 | /// [`iter`]: struct.HashMap.html#method.iter |
2291 | /// [`HashMap`]: struct.HashMap.html |
2292 | /// |
2293 | /// # Examples |
2294 | /// |
2295 | /// ``` |
2296 | /// use hashbrown::HashMap; |
2297 | /// |
2298 | /// let map: HashMap<_, _> = [(1, "a" ), (2, "b" ), (3, "c" )].into(); |
2299 | /// |
2300 | /// let mut iter = map.iter(); |
2301 | /// let mut vec = vec![iter.next(), iter.next(), iter.next()]; |
2302 | /// |
2303 | /// // The `Iter` iterator produces items in arbitrary order, so the |
2304 | /// // items must be sorted to test them against a sorted array. |
2305 | /// vec.sort_unstable(); |
2306 | /// assert_eq!(vec, [Some((&1, &"a" )), Some((&2, &"b" )), Some((&3, &"c" ))]); |
2307 | /// |
2308 | /// // It is fused iterator |
2309 | /// assert_eq!(iter.next(), None); |
2310 | /// assert_eq!(iter.next(), None); |
2311 | /// ``` |
2312 | pub struct Iter<'a, K, V> { |
2313 | inner: RawIter<(K, V)>, |
2314 | marker: PhantomData<(&'a K, &'a V)>, |
2315 | } |
2316 | |
2317 | // FIXME(#26925) Remove in favor of `#[derive(Clone)]` |
2318 | impl<K, V> Clone for Iter<'_, K, V> { |
2319 | #[cfg_attr (feature = "inline-more" , inline)] |
2320 | fn clone(&self) -> Self { |
2321 | Iter { |
2322 | inner: self.inner.clone(), |
2323 | marker: PhantomData, |
2324 | } |
2325 | } |
2326 | } |
2327 | |
2328 | impl<K: Debug, V: Debug> fmt::Debug for Iter<'_, K, V> { |
2329 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
2330 | f.debug_list().entries(self.clone()).finish() |
2331 | } |
2332 | } |
2333 | |
2334 | /// A mutable iterator over the entries of a `HashMap` in arbitrary order. |
2335 | /// The iterator element type is `(&'a K, &'a mut V)`. |
2336 | /// |
2337 | /// This `struct` is created by the [`iter_mut`] method on [`HashMap`]. See its |
2338 | /// documentation for more. |
2339 | /// |
2340 | /// [`iter_mut`]: struct.HashMap.html#method.iter_mut |
2341 | /// [`HashMap`]: struct.HashMap.html |
2342 | /// |
2343 | /// # Examples |
2344 | /// |
2345 | /// ``` |
2346 | /// use hashbrown::HashMap; |
2347 | /// |
2348 | /// let mut map: HashMap<_, _> = [(1, "One" .to_owned()), (2, "Two" .into())].into(); |
2349 | /// |
2350 | /// let mut iter = map.iter_mut(); |
2351 | /// iter.next().map(|(_, v)| v.push_str(" Mississippi" )); |
2352 | /// iter.next().map(|(_, v)| v.push_str(" Mississippi" )); |
2353 | /// |
2354 | /// // It is fused iterator |
2355 | /// assert_eq!(iter.next(), None); |
2356 | /// assert_eq!(iter.next(), None); |
2357 | /// |
2358 | /// assert_eq!(map.get(&1).unwrap(), &"One Mississippi" .to_owned()); |
2359 | /// assert_eq!(map.get(&2).unwrap(), &"Two Mississippi" .to_owned()); |
2360 | /// ``` |
2361 | pub struct IterMut<'a, K, V> { |
2362 | inner: RawIter<(K, V)>, |
2363 | // To ensure invariance with respect to V |
2364 | marker: PhantomData<(&'a K, &'a mut V)>, |
2365 | } |
2366 | |
2367 | // We override the default Send impl which has K: Sync instead of K: Send. Both |
2368 | // are correct, but this one is more general since it allows keys which |
2369 | // implement Send but not Sync. |
2370 | unsafe impl<K: Send, V: Send> Send for IterMut<'_, K, V> {} |
2371 | |
2372 | impl<K, V> IterMut<'_, K, V> { |
2373 | /// Returns a iterator of references over the remaining items. |
2374 | #[cfg_attr (feature = "inline-more" , inline)] |
2375 | pub(super) fn iter(&self) -> Iter<'_, K, V> { |
2376 | Iter { |
2377 | inner: self.inner.clone(), |
2378 | marker: PhantomData, |
2379 | } |
2380 | } |
2381 | } |
2382 | |
2383 | /// An owning iterator over the entries of a `HashMap` in arbitrary order. |
2384 | /// The iterator element type is `(K, V)`. |
2385 | /// |
2386 | /// This `struct` is created by the [`into_iter`] method on [`HashMap`] |
2387 | /// (provided by the [`IntoIterator`] trait). See its documentation for more. |
2388 | /// The map cannot be used after calling that method. |
2389 | /// |
2390 | /// [`into_iter`]: struct.HashMap.html#method.into_iter |
2391 | /// [`HashMap`]: struct.HashMap.html |
2392 | /// [`IntoIterator`]: https://doc.rust-lang.org/core/iter/trait.IntoIterator.html |
2393 | /// |
2394 | /// # Examples |
2395 | /// |
2396 | /// ``` |
2397 | /// use hashbrown::HashMap; |
2398 | /// |
2399 | /// let map: HashMap<_, _> = [(1, "a" ), (2, "b" ), (3, "c" )].into(); |
2400 | /// |
2401 | /// let mut iter = map.into_iter(); |
2402 | /// let mut vec = vec![iter.next(), iter.next(), iter.next()]; |
2403 | /// |
2404 | /// // The `IntoIter` iterator produces items in arbitrary order, so the |
2405 | /// // items must be sorted to test them against a sorted array. |
2406 | /// vec.sort_unstable(); |
2407 | /// assert_eq!(vec, [Some((1, "a" )), Some((2, "b" )), Some((3, "c" ))]); |
2408 | /// |
2409 | /// // It is fused iterator |
2410 | /// assert_eq!(iter.next(), None); |
2411 | /// assert_eq!(iter.next(), None); |
2412 | /// ``` |
2413 | pub struct IntoIter<K, V, A: Allocator = Global> { |
2414 | inner: RawIntoIter<(K, V), A>, |
2415 | } |
2416 | |
2417 | impl<K, V, A: Allocator> IntoIter<K, V, A> { |
2418 | /// Returns a iterator of references over the remaining items. |
2419 | #[cfg_attr (feature = "inline-more" , inline)] |
2420 | pub(super) fn iter(&self) -> Iter<'_, K, V> { |
2421 | Iter { |
2422 | inner: self.inner.iter(), |
2423 | marker: PhantomData, |
2424 | } |
2425 | } |
2426 | } |
2427 | |
2428 | /// An owning iterator over the keys of a `HashMap` in arbitrary order. |
2429 | /// The iterator element type is `K`. |
2430 | /// |
2431 | /// This `struct` is created by the [`into_keys`] method on [`HashMap`]. |
2432 | /// See its documentation for more. |
2433 | /// The map cannot be used after calling that method. |
2434 | /// |
2435 | /// [`into_keys`]: struct.HashMap.html#method.into_keys |
2436 | /// [`HashMap`]: struct.HashMap.html |
2437 | /// |
2438 | /// # Examples |
2439 | /// |
2440 | /// ``` |
2441 | /// use hashbrown::HashMap; |
2442 | /// |
2443 | /// let map: HashMap<_, _> = [(1, "a" ), (2, "b" ), (3, "c" )].into(); |
2444 | /// |
2445 | /// let mut keys = map.into_keys(); |
2446 | /// let mut vec = vec![keys.next(), keys.next(), keys.next()]; |
2447 | /// |
2448 | /// // The `IntoKeys` iterator produces keys in arbitrary order, so the |
2449 | /// // keys must be sorted to test them against a sorted array. |
2450 | /// vec.sort_unstable(); |
2451 | /// assert_eq!(vec, [Some(1), Some(2), Some(3)]); |
2452 | /// |
2453 | /// // It is fused iterator |
2454 | /// assert_eq!(keys.next(), None); |
2455 | /// assert_eq!(keys.next(), None); |
2456 | /// ``` |
2457 | pub struct IntoKeys<K, V, A: Allocator = Global> { |
2458 | inner: IntoIter<K, V, A>, |
2459 | } |
2460 | |
2461 | impl<K, V, A: Allocator> Iterator for IntoKeys<K, V, A> { |
2462 | type Item = K; |
2463 | |
2464 | #[inline ] |
2465 | fn next(&mut self) -> Option<K> { |
2466 | self.inner.next().map(|(k, _)| k) |
2467 | } |
2468 | #[inline ] |
2469 | fn size_hint(&self) -> (usize, Option<usize>) { |
2470 | self.inner.size_hint() |
2471 | } |
2472 | #[inline ] |
2473 | fn fold<B, F>(self, init: B, mut f: F) -> B |
2474 | where |
2475 | Self: Sized, |
2476 | F: FnMut(B, Self::Item) -> B, |
2477 | { |
2478 | self.inner.fold(init, |acc, (k, _)| f(acc, k)) |
2479 | } |
2480 | } |
2481 | |
2482 | impl<K, V, A: Allocator> ExactSizeIterator for IntoKeys<K, V, A> { |
2483 | #[inline ] |
2484 | fn len(&self) -> usize { |
2485 | self.inner.len() |
2486 | } |
2487 | } |
2488 | |
2489 | impl<K, V, A: Allocator> FusedIterator for IntoKeys<K, V, A> {} |
2490 | |
2491 | impl<K: Debug, V: Debug, A: Allocator> fmt::Debug for IntoKeys<K, V, A> { |
2492 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
2493 | f.debug_list() |
2494 | .entries(self.inner.iter().map(|(k, _)| k)) |
2495 | .finish() |
2496 | } |
2497 | } |
2498 | |
2499 | /// An owning iterator over the values of a `HashMap` in arbitrary order. |
2500 | /// The iterator element type is `V`. |
2501 | /// |
2502 | /// This `struct` is created by the [`into_values`] method on [`HashMap`]. |
2503 | /// See its documentation for more. The map cannot be used after calling that method. |
2504 | /// |
2505 | /// [`into_values`]: struct.HashMap.html#method.into_values |
2506 | /// [`HashMap`]: struct.HashMap.html |
2507 | /// |
2508 | /// # Examples |
2509 | /// |
2510 | /// ``` |
2511 | /// use hashbrown::HashMap; |
2512 | /// |
2513 | /// let map: HashMap<_, _> = [(1, "a" ), (2, "b" ), (3, "c" )].into(); |
2514 | /// |
2515 | /// let mut values = map.into_values(); |
2516 | /// let mut vec = vec![values.next(), values.next(), values.next()]; |
2517 | /// |
2518 | /// // The `IntoValues` iterator produces values in arbitrary order, so |
2519 | /// // the values must be sorted to test them against a sorted array. |
2520 | /// vec.sort_unstable(); |
2521 | /// assert_eq!(vec, [Some("a" ), Some("b" ), Some("c" )]); |
2522 | /// |
2523 | /// // It is fused iterator |
2524 | /// assert_eq!(values.next(), None); |
2525 | /// assert_eq!(values.next(), None); |
2526 | /// ``` |
2527 | pub struct IntoValues<K, V, A: Allocator = Global> { |
2528 | inner: IntoIter<K, V, A>, |
2529 | } |
2530 | |
2531 | impl<K, V, A: Allocator> Iterator for IntoValues<K, V, A> { |
2532 | type Item = V; |
2533 | |
2534 | #[inline ] |
2535 | fn next(&mut self) -> Option<V> { |
2536 | self.inner.next().map(|(_, v)| v) |
2537 | } |
2538 | #[inline ] |
2539 | fn size_hint(&self) -> (usize, Option<usize>) { |
2540 | self.inner.size_hint() |
2541 | } |
2542 | #[inline ] |
2543 | fn fold<B, F>(self, init: B, mut f: F) -> B |
2544 | where |
2545 | Self: Sized, |
2546 | F: FnMut(B, Self::Item) -> B, |
2547 | { |
2548 | self.inner.fold(init, |acc, (_, v)| f(acc, v)) |
2549 | } |
2550 | } |
2551 | |
2552 | impl<K, V, A: Allocator> ExactSizeIterator for IntoValues<K, V, A> { |
2553 | #[inline ] |
2554 | fn len(&self) -> usize { |
2555 | self.inner.len() |
2556 | } |
2557 | } |
2558 | |
2559 | impl<K, V, A: Allocator> FusedIterator for IntoValues<K, V, A> {} |
2560 | |
2561 | impl<K, V: Debug, A: Allocator> fmt::Debug for IntoValues<K, V, A> { |
2562 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
2563 | f.debug_list() |
2564 | .entries(self.inner.iter().map(|(_, v)| v)) |
2565 | .finish() |
2566 | } |
2567 | } |
2568 | |
2569 | /// An iterator over the keys of a `HashMap` in arbitrary order. |
2570 | /// The iterator element type is `&'a K`. |
2571 | /// |
2572 | /// This `struct` is created by the [`keys`] method on [`HashMap`]. See its |
2573 | /// documentation for more. |
2574 | /// |
2575 | /// [`keys`]: struct.HashMap.html#method.keys |
2576 | /// [`HashMap`]: struct.HashMap.html |
2577 | /// |
2578 | /// # Examples |
2579 | /// |
2580 | /// ``` |
2581 | /// use hashbrown::HashMap; |
2582 | /// |
2583 | /// let map: HashMap<_, _> = [(1, "a" ), (2, "b" ), (3, "c" )].into(); |
2584 | /// |
2585 | /// let mut keys = map.keys(); |
2586 | /// let mut vec = vec![keys.next(), keys.next(), keys.next()]; |
2587 | /// |
2588 | /// // The `Keys` iterator produces keys in arbitrary order, so the |
2589 | /// // keys must be sorted to test them against a sorted array. |
2590 | /// vec.sort_unstable(); |
2591 | /// assert_eq!(vec, [Some(&1), Some(&2), Some(&3)]); |
2592 | /// |
2593 | /// // It is fused iterator |
2594 | /// assert_eq!(keys.next(), None); |
2595 | /// assert_eq!(keys.next(), None); |
2596 | /// ``` |
2597 | pub struct Keys<'a, K, V> { |
2598 | inner: Iter<'a, K, V>, |
2599 | } |
2600 | |
2601 | // FIXME(#26925) Remove in favor of `#[derive(Clone)]` |
2602 | impl<K, V> Clone for Keys<'_, K, V> { |
2603 | #[cfg_attr (feature = "inline-more" , inline)] |
2604 | fn clone(&self) -> Self { |
2605 | Keys { |
2606 | inner: self.inner.clone(), |
2607 | } |
2608 | } |
2609 | } |
2610 | |
2611 | impl<K: Debug, V> fmt::Debug for Keys<'_, K, V> { |
2612 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
2613 | f.debug_list().entries(self.clone()).finish() |
2614 | } |
2615 | } |
2616 | |
2617 | /// An iterator over the values of a `HashMap` in arbitrary order. |
2618 | /// The iterator element type is `&'a V`. |
2619 | /// |
2620 | /// This `struct` is created by the [`values`] method on [`HashMap`]. See its |
2621 | /// documentation for more. |
2622 | /// |
2623 | /// [`values`]: struct.HashMap.html#method.values |
2624 | /// [`HashMap`]: struct.HashMap.html |
2625 | /// |
2626 | /// # Examples |
2627 | /// |
2628 | /// ``` |
2629 | /// use hashbrown::HashMap; |
2630 | /// |
2631 | /// let map: HashMap<_, _> = [(1, "a" ), (2, "b" ), (3, "c" )].into(); |
2632 | /// |
2633 | /// let mut values = map.values(); |
2634 | /// let mut vec = vec![values.next(), values.next(), values.next()]; |
2635 | /// |
2636 | /// // The `Values` iterator produces values in arbitrary order, so the |
2637 | /// // values must be sorted to test them against a sorted array. |
2638 | /// vec.sort_unstable(); |
2639 | /// assert_eq!(vec, [Some(&"a" ), Some(&"b" ), Some(&"c" )]); |
2640 | /// |
2641 | /// // It is fused iterator |
2642 | /// assert_eq!(values.next(), None); |
2643 | /// assert_eq!(values.next(), None); |
2644 | /// ``` |
2645 | pub struct Values<'a, K, V> { |
2646 | inner: Iter<'a, K, V>, |
2647 | } |
2648 | |
2649 | // FIXME(#26925) Remove in favor of `#[derive(Clone)]` |
2650 | impl<K, V> Clone for Values<'_, K, V> { |
2651 | #[cfg_attr (feature = "inline-more" , inline)] |
2652 | fn clone(&self) -> Self { |
2653 | Values { |
2654 | inner: self.inner.clone(), |
2655 | } |
2656 | } |
2657 | } |
2658 | |
2659 | impl<K, V: Debug> fmt::Debug for Values<'_, K, V> { |
2660 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
2661 | f.debug_list().entries(self.clone()).finish() |
2662 | } |
2663 | } |
2664 | |
2665 | /// A draining iterator over the entries of a `HashMap` in arbitrary |
2666 | /// order. The iterator element type is `(K, V)`. |
2667 | /// |
2668 | /// This `struct` is created by the [`drain`] method on [`HashMap`]. See its |
2669 | /// documentation for more. |
2670 | /// |
2671 | /// [`drain`]: struct.HashMap.html#method.drain |
2672 | /// [`HashMap`]: struct.HashMap.html |
2673 | /// |
2674 | /// # Examples |
2675 | /// |
2676 | /// ``` |
2677 | /// use hashbrown::HashMap; |
2678 | /// |
2679 | /// let mut map: HashMap<_, _> = [(1, "a" ), (2, "b" ), (3, "c" )].into(); |
2680 | /// |
2681 | /// let mut drain_iter = map.drain(); |
2682 | /// let mut vec = vec![drain_iter.next(), drain_iter.next(), drain_iter.next()]; |
2683 | /// |
2684 | /// // The `Drain` iterator produces items in arbitrary order, so the |
2685 | /// // items must be sorted to test them against a sorted array. |
2686 | /// vec.sort_unstable(); |
2687 | /// assert_eq!(vec, [Some((1, "a" )), Some((2, "b" )), Some((3, "c" ))]); |
2688 | /// |
2689 | /// // It is fused iterator |
2690 | /// assert_eq!(drain_iter.next(), None); |
2691 | /// assert_eq!(drain_iter.next(), None); |
2692 | /// ``` |
2693 | pub struct Drain<'a, K, V, A: Allocator = Global> { |
2694 | inner: RawDrain<'a, (K, V), A>, |
2695 | } |
2696 | |
2697 | impl<K, V, A: Allocator> Drain<'_, K, V, A> { |
2698 | /// Returns a iterator of references over the remaining items. |
2699 | #[cfg_attr (feature = "inline-more" , inline)] |
2700 | pub(super) fn iter(&self) -> Iter<'_, K, V> { |
2701 | Iter { |
2702 | inner: self.inner.iter(), |
2703 | marker: PhantomData, |
2704 | } |
2705 | } |
2706 | } |
2707 | |
2708 | /// A draining iterator over entries of a `HashMap` which don't satisfy the predicate |
2709 | /// `f(&k, &mut v)` in arbitrary order. The iterator element type is `(K, V)`. |
2710 | /// |
2711 | /// This `struct` is created by the [`extract_if`] method on [`HashMap`]. See its |
2712 | /// documentation for more. |
2713 | /// |
2714 | /// [`extract_if`]: struct.HashMap.html#method.extract_if |
2715 | /// [`HashMap`]: struct.HashMap.html |
2716 | /// |
2717 | /// # Examples |
2718 | /// |
2719 | /// ``` |
2720 | /// use hashbrown::HashMap; |
2721 | /// |
2722 | /// let mut map: HashMap<i32, &str> = [(1, "a" ), (2, "b" ), (3, "c" )].into(); |
2723 | /// |
2724 | /// let mut extract_if = map.extract_if(|k, _v| k % 2 != 0); |
2725 | /// let mut vec = vec![extract_if.next(), extract_if.next()]; |
2726 | /// |
2727 | /// // The `ExtractIf` iterator produces items in arbitrary order, so the |
2728 | /// // items must be sorted to test them against a sorted array. |
2729 | /// vec.sort_unstable(); |
2730 | /// assert_eq!(vec, [Some((1, "a" )),Some((3, "c" ))]); |
2731 | /// |
2732 | /// // It is fused iterator |
2733 | /// assert_eq!(extract_if.next(), None); |
2734 | /// assert_eq!(extract_if.next(), None); |
2735 | /// drop(extract_if); |
2736 | /// |
2737 | /// assert_eq!(map.len(), 1); |
2738 | /// ``` |
2739 | #[must_use = "Iterators are lazy unless consumed" ] |
2740 | pub struct ExtractIf<'a, K, V, F, A: Allocator = Global> |
2741 | where |
2742 | F: FnMut(&K, &mut V) -> bool, |
2743 | { |
2744 | f: F, |
2745 | inner: RawExtractIf<'a, (K, V), A>, |
2746 | } |
2747 | |
2748 | impl<K, V, F, A> Iterator for ExtractIf<'_, K, V, F, A> |
2749 | where |
2750 | F: FnMut(&K, &mut V) -> bool, |
2751 | A: Allocator, |
2752 | { |
2753 | type Item = (K, V); |
2754 | |
2755 | #[cfg_attr (feature = "inline-more" , inline)] |
2756 | fn next(&mut self) -> Option<Self::Item> { |
2757 | self.inner.next(|&mut (ref k: &{unknown}, ref mut v: &mut {unknown})| (self.f)(k, v)) |
2758 | } |
2759 | |
2760 | #[inline ] |
2761 | fn size_hint(&self) -> (usize, Option<usize>) { |
2762 | (0, self.inner.iter.size_hint().1) |
2763 | } |
2764 | } |
2765 | |
2766 | impl<K, V, F> FusedIterator for ExtractIf<'_, K, V, F> where F: FnMut(&K, &mut V) -> bool {} |
2767 | |
2768 | /// A mutable iterator over the values of a `HashMap` in arbitrary order. |
2769 | /// The iterator element type is `&'a mut V`. |
2770 | /// |
2771 | /// This `struct` is created by the [`values_mut`] method on [`HashMap`]. See its |
2772 | /// documentation for more. |
2773 | /// |
2774 | /// [`values_mut`]: struct.HashMap.html#method.values_mut |
2775 | /// [`HashMap`]: struct.HashMap.html |
2776 | /// |
2777 | /// # Examples |
2778 | /// |
2779 | /// ``` |
2780 | /// use hashbrown::HashMap; |
2781 | /// |
2782 | /// let mut map: HashMap<_, _> = [(1, "One" .to_owned()), (2, "Two" .into())].into(); |
2783 | /// |
2784 | /// let mut values = map.values_mut(); |
2785 | /// values.next().map(|v| v.push_str(" Mississippi" )); |
2786 | /// values.next().map(|v| v.push_str(" Mississippi" )); |
2787 | /// |
2788 | /// // It is fused iterator |
2789 | /// assert_eq!(values.next(), None); |
2790 | /// assert_eq!(values.next(), None); |
2791 | /// |
2792 | /// assert_eq!(map.get(&1).unwrap(), &"One Mississippi" .to_owned()); |
2793 | /// assert_eq!(map.get(&2).unwrap(), &"Two Mississippi" .to_owned()); |
2794 | /// ``` |
2795 | pub struct ValuesMut<'a, K, V> { |
2796 | inner: IterMut<'a, K, V>, |
2797 | } |
2798 | |
2799 | /// A builder for computing where in a [`HashMap`] a key-value pair would be stored. |
2800 | /// |
2801 | /// See the [`HashMap::raw_entry_mut`] docs for usage examples. |
2802 | /// |
2803 | /// [`HashMap::raw_entry_mut`]: struct.HashMap.html#method.raw_entry_mut |
2804 | /// |
2805 | /// # Examples |
2806 | /// |
2807 | /// ``` |
2808 | /// use hashbrown::hash_map::{RawEntryBuilderMut, RawEntryMut::Vacant, RawEntryMut::Occupied}; |
2809 | /// use hashbrown::HashMap; |
2810 | /// use core::hash::{BuildHasher, Hash}; |
2811 | /// |
2812 | /// let mut map = HashMap::new(); |
2813 | /// map.extend([(1, 11), (2, 12), (3, 13), (4, 14), (5, 15), (6, 16)]); |
2814 | /// assert_eq!(map.len(), 6); |
2815 | /// |
2816 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
2817 | /// use core::hash::Hasher; |
2818 | /// let mut state = hash_builder.build_hasher(); |
2819 | /// key.hash(&mut state); |
2820 | /// state.finish() |
2821 | /// } |
2822 | /// |
2823 | /// let builder: RawEntryBuilderMut<_, _, _> = map.raw_entry_mut(); |
2824 | /// |
2825 | /// // Existing key |
2826 | /// match builder.from_key(&6) { |
2827 | /// Vacant(_) => unreachable!(), |
2828 | /// Occupied(view) => assert_eq!(view.get(), &16), |
2829 | /// } |
2830 | /// |
2831 | /// for key in 0..12 { |
2832 | /// let hash = compute_hash(map.hasher(), &key); |
2833 | /// let value = map.get(&key).cloned(); |
2834 | /// let key_value = value.as_ref().map(|v| (&key, v)); |
2835 | /// |
2836 | /// println!("Key: {} and value: {:?}" , key, value); |
2837 | /// |
2838 | /// match map.raw_entry_mut().from_key(&key) { |
2839 | /// Occupied(mut o) => assert_eq!(Some(o.get_key_value()), key_value), |
2840 | /// Vacant(_) => assert_eq!(value, None), |
2841 | /// } |
2842 | /// match map.raw_entry_mut().from_key_hashed_nocheck(hash, &key) { |
2843 | /// Occupied(mut o) => assert_eq!(Some(o.get_key_value()), key_value), |
2844 | /// Vacant(_) => assert_eq!(value, None), |
2845 | /// } |
2846 | /// match map.raw_entry_mut().from_hash(hash, |q| *q == key) { |
2847 | /// Occupied(mut o) => assert_eq!(Some(o.get_key_value()), key_value), |
2848 | /// Vacant(_) => assert_eq!(value, None), |
2849 | /// } |
2850 | /// } |
2851 | /// |
2852 | /// assert_eq!(map.len(), 6); |
2853 | /// ``` |
2854 | pub struct RawEntryBuilderMut<'a, K, V, S, A: Allocator = Global> { |
2855 | map: &'a mut HashMap<K, V, S, A>, |
2856 | } |
2857 | |
2858 | /// A view into a single entry in a map, which may either be vacant or occupied. |
2859 | /// |
2860 | /// This is a lower-level version of [`Entry`]. |
2861 | /// |
2862 | /// This `enum` is constructed through the [`raw_entry_mut`] method on [`HashMap`], |
2863 | /// then calling one of the methods of that [`RawEntryBuilderMut`]. |
2864 | /// |
2865 | /// [`HashMap`]: struct.HashMap.html |
2866 | /// [`Entry`]: enum.Entry.html |
2867 | /// [`raw_entry_mut`]: struct.HashMap.html#method.raw_entry_mut |
2868 | /// [`RawEntryBuilderMut`]: struct.RawEntryBuilderMut.html |
2869 | /// |
2870 | /// # Examples |
2871 | /// |
2872 | /// ``` |
2873 | /// use core::hash::{BuildHasher, Hash}; |
2874 | /// use hashbrown::hash_map::{HashMap, RawEntryMut, RawOccupiedEntryMut}; |
2875 | /// |
2876 | /// let mut map = HashMap::new(); |
2877 | /// map.extend([('a' , 1), ('b' , 2), ('c' , 3)]); |
2878 | /// assert_eq!(map.len(), 3); |
2879 | /// |
2880 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
2881 | /// use core::hash::Hasher; |
2882 | /// let mut state = hash_builder.build_hasher(); |
2883 | /// key.hash(&mut state); |
2884 | /// state.finish() |
2885 | /// } |
2886 | /// |
2887 | /// // Existing key (insert) |
2888 | /// let raw: RawEntryMut<_, _, _> = map.raw_entry_mut().from_key(&'a' ); |
2889 | /// let _raw_o: RawOccupiedEntryMut<_, _, _> = raw.insert('a' , 10); |
2890 | /// assert_eq!(map.len(), 3); |
2891 | /// |
2892 | /// // Nonexistent key (insert) |
2893 | /// map.raw_entry_mut().from_key(&'d' ).insert('d' , 40); |
2894 | /// assert_eq!(map.len(), 4); |
2895 | /// |
2896 | /// // Existing key (or_insert) |
2897 | /// let hash = compute_hash(map.hasher(), &'b' ); |
2898 | /// let kv = map |
2899 | /// .raw_entry_mut() |
2900 | /// .from_key_hashed_nocheck(hash, &'b' ) |
2901 | /// .or_insert('b' , 20); |
2902 | /// assert_eq!(kv, (&mut 'b' , &mut 2)); |
2903 | /// *kv.1 = 20; |
2904 | /// assert_eq!(map.len(), 4); |
2905 | /// |
2906 | /// // Nonexistent key (or_insert) |
2907 | /// let hash = compute_hash(map.hasher(), &'e' ); |
2908 | /// let kv = map |
2909 | /// .raw_entry_mut() |
2910 | /// .from_key_hashed_nocheck(hash, &'e' ) |
2911 | /// .or_insert('e' , 50); |
2912 | /// assert_eq!(kv, (&mut 'e' , &mut 50)); |
2913 | /// assert_eq!(map.len(), 5); |
2914 | /// |
2915 | /// // Existing key (or_insert_with) |
2916 | /// let hash = compute_hash(map.hasher(), &'c' ); |
2917 | /// let kv = map |
2918 | /// .raw_entry_mut() |
2919 | /// .from_hash(hash, |q| q == &'c' ) |
2920 | /// .or_insert_with(|| ('c' , 30)); |
2921 | /// assert_eq!(kv, (&mut 'c' , &mut 3)); |
2922 | /// *kv.1 = 30; |
2923 | /// assert_eq!(map.len(), 5); |
2924 | /// |
2925 | /// // Nonexistent key (or_insert_with) |
2926 | /// let hash = compute_hash(map.hasher(), &'f' ); |
2927 | /// let kv = map |
2928 | /// .raw_entry_mut() |
2929 | /// .from_hash(hash, |q| q == &'f' ) |
2930 | /// .or_insert_with(|| ('f' , 60)); |
2931 | /// assert_eq!(kv, (&mut 'f' , &mut 60)); |
2932 | /// assert_eq!(map.len(), 6); |
2933 | /// |
2934 | /// println!("Our HashMap: {:?}" , map); |
2935 | /// |
2936 | /// let mut vec: Vec<_> = map.iter().map(|(&k, &v)| (k, v)).collect(); |
2937 | /// // The `Iter` iterator produces items in arbitrary order, so the |
2938 | /// // items must be sorted to test them against a sorted array. |
2939 | /// vec.sort_unstable(); |
2940 | /// assert_eq!(vec, [('a' , 10), ('b' , 20), ('c' , 30), ('d' , 40), ('e' , 50), ('f' , 60)]); |
2941 | /// ``` |
2942 | pub enum RawEntryMut<'a, K, V, S, A: Allocator = Global> { |
2943 | /// An occupied entry. |
2944 | /// |
2945 | /// # Examples |
2946 | /// |
2947 | /// ``` |
2948 | /// use hashbrown::{hash_map::RawEntryMut, HashMap}; |
2949 | /// let mut map: HashMap<_, _> = [("a" , 100), ("b" , 200)].into(); |
2950 | /// |
2951 | /// match map.raw_entry_mut().from_key(&"a" ) { |
2952 | /// RawEntryMut::Vacant(_) => unreachable!(), |
2953 | /// RawEntryMut::Occupied(_) => { } |
2954 | /// } |
2955 | /// ``` |
2956 | Occupied(RawOccupiedEntryMut<'a, K, V, S, A>), |
2957 | /// A vacant entry. |
2958 | /// |
2959 | /// # Examples |
2960 | /// |
2961 | /// ``` |
2962 | /// use hashbrown::{hash_map::RawEntryMut, HashMap}; |
2963 | /// let mut map: HashMap<&str, i32> = HashMap::new(); |
2964 | /// |
2965 | /// match map.raw_entry_mut().from_key("a" ) { |
2966 | /// RawEntryMut::Occupied(_) => unreachable!(), |
2967 | /// RawEntryMut::Vacant(_) => { } |
2968 | /// } |
2969 | /// ``` |
2970 | Vacant(RawVacantEntryMut<'a, K, V, S, A>), |
2971 | } |
2972 | |
2973 | /// A view into an occupied entry in a `HashMap`. |
2974 | /// It is part of the [`RawEntryMut`] enum. |
2975 | /// |
2976 | /// [`RawEntryMut`]: enum.RawEntryMut.html |
2977 | /// |
2978 | /// # Examples |
2979 | /// |
2980 | /// ``` |
2981 | /// use core::hash::{BuildHasher, Hash}; |
2982 | /// use hashbrown::hash_map::{HashMap, RawEntryMut, RawOccupiedEntryMut}; |
2983 | /// |
2984 | /// let mut map = HashMap::new(); |
2985 | /// map.extend([("a" , 10), ("b" , 20), ("c" , 30)]); |
2986 | /// |
2987 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
2988 | /// use core::hash::Hasher; |
2989 | /// let mut state = hash_builder.build_hasher(); |
2990 | /// key.hash(&mut state); |
2991 | /// state.finish() |
2992 | /// } |
2993 | /// |
2994 | /// let _raw_o: RawOccupiedEntryMut<_, _, _> = map.raw_entry_mut().from_key(&"a" ).insert("a" , 100); |
2995 | /// assert_eq!(map.len(), 3); |
2996 | /// |
2997 | /// // Existing key (insert and update) |
2998 | /// match map.raw_entry_mut().from_key(&"a" ) { |
2999 | /// RawEntryMut::Vacant(_) => unreachable!(), |
3000 | /// RawEntryMut::Occupied(mut view) => { |
3001 | /// assert_eq!(view.get(), &100); |
3002 | /// let v = view.get_mut(); |
3003 | /// let new_v = (*v) * 10; |
3004 | /// *v = new_v; |
3005 | /// assert_eq!(view.insert(1111), 1000); |
3006 | /// } |
3007 | /// } |
3008 | /// |
3009 | /// assert_eq!(map[&"a" ], 1111); |
3010 | /// assert_eq!(map.len(), 3); |
3011 | /// |
3012 | /// // Existing key (take) |
3013 | /// let hash = compute_hash(map.hasher(), &"c" ); |
3014 | /// match map.raw_entry_mut().from_key_hashed_nocheck(hash, &"c" ) { |
3015 | /// RawEntryMut::Vacant(_) => unreachable!(), |
3016 | /// RawEntryMut::Occupied(view) => { |
3017 | /// assert_eq!(view.remove_entry(), ("c" , 30)); |
3018 | /// } |
3019 | /// } |
3020 | /// assert_eq!(map.raw_entry().from_key(&"c" ), None); |
3021 | /// assert_eq!(map.len(), 2); |
3022 | /// |
3023 | /// let hash = compute_hash(map.hasher(), &"b" ); |
3024 | /// match map.raw_entry_mut().from_hash(hash, |q| *q == "b" ) { |
3025 | /// RawEntryMut::Vacant(_) => unreachable!(), |
3026 | /// RawEntryMut::Occupied(view) => { |
3027 | /// assert_eq!(view.remove_entry(), ("b" , 20)); |
3028 | /// } |
3029 | /// } |
3030 | /// assert_eq!(map.get(&"b" ), None); |
3031 | /// assert_eq!(map.len(), 1); |
3032 | /// ``` |
3033 | pub struct RawOccupiedEntryMut<'a, K, V, S, A: Allocator = Global> { |
3034 | elem: Bucket<(K, V)>, |
3035 | table: &'a mut RawTable<(K, V), A>, |
3036 | hash_builder: &'a S, |
3037 | } |
3038 | |
3039 | unsafe impl<K, V, S, A> Send for RawOccupiedEntryMut<'_, K, V, S, A> |
3040 | where |
3041 | K: Send, |
3042 | V: Send, |
3043 | S: Send, |
3044 | A: Send + Allocator, |
3045 | { |
3046 | } |
3047 | unsafe impl<K, V, S, A> Sync for RawOccupiedEntryMut<'_, K, V, S, A> |
3048 | where |
3049 | K: Sync, |
3050 | V: Sync, |
3051 | S: Sync, |
3052 | A: Sync + Allocator, |
3053 | { |
3054 | } |
3055 | |
3056 | /// A view into a vacant entry in a `HashMap`. |
3057 | /// It is part of the [`RawEntryMut`] enum. |
3058 | /// |
3059 | /// [`RawEntryMut`]: enum.RawEntryMut.html |
3060 | /// |
3061 | /// # Examples |
3062 | /// |
3063 | /// ``` |
3064 | /// use core::hash::{BuildHasher, Hash}; |
3065 | /// use hashbrown::hash_map::{HashMap, RawEntryMut, RawVacantEntryMut}; |
3066 | /// |
3067 | /// let mut map = HashMap::<&str, i32>::new(); |
3068 | /// |
3069 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
3070 | /// use core::hash::Hasher; |
3071 | /// let mut state = hash_builder.build_hasher(); |
3072 | /// key.hash(&mut state); |
3073 | /// state.finish() |
3074 | /// } |
3075 | /// |
3076 | /// let raw_v: RawVacantEntryMut<_, _, _> = match map.raw_entry_mut().from_key(&"a" ) { |
3077 | /// RawEntryMut::Vacant(view) => view, |
3078 | /// RawEntryMut::Occupied(_) => unreachable!(), |
3079 | /// }; |
3080 | /// raw_v.insert("a" , 10); |
3081 | /// assert!(map[&"a" ] == 10 && map.len() == 1); |
3082 | /// |
3083 | /// // Nonexistent key (insert and update) |
3084 | /// let hash = compute_hash(map.hasher(), &"b" ); |
3085 | /// match map.raw_entry_mut().from_key_hashed_nocheck(hash, &"b" ) { |
3086 | /// RawEntryMut::Occupied(_) => unreachable!(), |
3087 | /// RawEntryMut::Vacant(view) => { |
3088 | /// let (k, value) = view.insert("b" , 2); |
3089 | /// assert_eq!((*k, *value), ("b" , 2)); |
3090 | /// *value = 20; |
3091 | /// } |
3092 | /// } |
3093 | /// assert!(map[&"b" ] == 20 && map.len() == 2); |
3094 | /// |
3095 | /// let hash = compute_hash(map.hasher(), &"c" ); |
3096 | /// match map.raw_entry_mut().from_hash(hash, |q| *q == "c" ) { |
3097 | /// RawEntryMut::Occupied(_) => unreachable!(), |
3098 | /// RawEntryMut::Vacant(view) => { |
3099 | /// assert_eq!(view.insert("c" , 30), (&mut "c" , &mut 30)); |
3100 | /// } |
3101 | /// } |
3102 | /// assert!(map[&"c" ] == 30 && map.len() == 3); |
3103 | /// ``` |
3104 | pub struct RawVacantEntryMut<'a, K, V, S, A: Allocator = Global> { |
3105 | table: &'a mut RawTable<(K, V), A>, |
3106 | hash_builder: &'a S, |
3107 | } |
3108 | |
3109 | /// A builder for computing where in a [`HashMap`] a key-value pair would be stored. |
3110 | /// |
3111 | /// See the [`HashMap::raw_entry`] docs for usage examples. |
3112 | /// |
3113 | /// [`HashMap::raw_entry`]: struct.HashMap.html#method.raw_entry |
3114 | /// |
3115 | /// # Examples |
3116 | /// |
3117 | /// ``` |
3118 | /// use hashbrown::hash_map::{HashMap, RawEntryBuilder}; |
3119 | /// use core::hash::{BuildHasher, Hash}; |
3120 | /// |
3121 | /// let mut map = HashMap::new(); |
3122 | /// map.extend([(1, 10), (2, 20), (3, 30)]); |
3123 | /// |
3124 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
3125 | /// use core::hash::Hasher; |
3126 | /// let mut state = hash_builder.build_hasher(); |
3127 | /// key.hash(&mut state); |
3128 | /// state.finish() |
3129 | /// } |
3130 | /// |
3131 | /// for k in 0..6 { |
3132 | /// let hash = compute_hash(map.hasher(), &k); |
3133 | /// let v = map.get(&k).cloned(); |
3134 | /// let kv = v.as_ref().map(|v| (&k, v)); |
3135 | /// |
3136 | /// println!("Key: {} and value: {:?}" , k, v); |
3137 | /// let builder: RawEntryBuilder<_, _, _> = map.raw_entry(); |
3138 | /// assert_eq!(builder.from_key(&k), kv); |
3139 | /// assert_eq!(map.raw_entry().from_hash(hash, |q| *q == k), kv); |
3140 | /// assert_eq!(map.raw_entry().from_key_hashed_nocheck(hash, &k), kv); |
3141 | /// } |
3142 | /// ``` |
3143 | pub struct RawEntryBuilder<'a, K, V, S, A: Allocator = Global> { |
3144 | map: &'a HashMap<K, V, S, A>, |
3145 | } |
3146 | |
3147 | impl<'a, K, V, S, A: Allocator> RawEntryBuilderMut<'a, K, V, S, A> { |
3148 | /// Creates a `RawEntryMut` from the given key. |
3149 | /// |
3150 | /// # Examples |
3151 | /// |
3152 | /// ``` |
3153 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3154 | /// |
3155 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
3156 | /// let key = "a" ; |
3157 | /// let entry: RawEntryMut<&str, u32, _> = map.raw_entry_mut().from_key(&key); |
3158 | /// entry.insert(key, 100); |
3159 | /// assert_eq!(map[&"a" ], 100); |
3160 | /// ``` |
3161 | #[cfg_attr (feature = "inline-more" , inline)] |
3162 | #[allow (clippy::wrong_self_convention)] |
3163 | pub fn from_key<Q: ?Sized>(self, k: &Q) -> RawEntryMut<'a, K, V, S, A> |
3164 | where |
3165 | S: BuildHasher, |
3166 | Q: Hash + Equivalent<K>, |
3167 | { |
3168 | let hash = make_hash::<Q, S>(&self.map.hash_builder, k); |
3169 | self.from_key_hashed_nocheck(hash, k) |
3170 | } |
3171 | |
3172 | /// Creates a `RawEntryMut` from the given key and its hash. |
3173 | /// |
3174 | /// # Examples |
3175 | /// |
3176 | /// ``` |
3177 | /// use core::hash::{BuildHasher, Hash}; |
3178 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3179 | /// |
3180 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
3181 | /// use core::hash::Hasher; |
3182 | /// let mut state = hash_builder.build_hasher(); |
3183 | /// key.hash(&mut state); |
3184 | /// state.finish() |
3185 | /// } |
3186 | /// |
3187 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
3188 | /// let key = "a" ; |
3189 | /// let hash = compute_hash(map.hasher(), &key); |
3190 | /// let entry: RawEntryMut<&str, u32, _> = map.raw_entry_mut().from_key_hashed_nocheck(hash, &key); |
3191 | /// entry.insert(key, 100); |
3192 | /// assert_eq!(map[&"a" ], 100); |
3193 | /// ``` |
3194 | #[inline ] |
3195 | #[allow (clippy::wrong_self_convention)] |
3196 | pub fn from_key_hashed_nocheck<Q: ?Sized>(self, hash: u64, k: &Q) -> RawEntryMut<'a, K, V, S, A> |
3197 | where |
3198 | Q: Equivalent<K>, |
3199 | { |
3200 | self.from_hash(hash, equivalent(k)) |
3201 | } |
3202 | } |
3203 | |
3204 | impl<'a, K, V, S, A: Allocator> RawEntryBuilderMut<'a, K, V, S, A> { |
3205 | /// Creates a `RawEntryMut` from the given hash and matching function. |
3206 | /// |
3207 | /// # Examples |
3208 | /// |
3209 | /// ``` |
3210 | /// use core::hash::{BuildHasher, Hash}; |
3211 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3212 | /// |
3213 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
3214 | /// use core::hash::Hasher; |
3215 | /// let mut state = hash_builder.build_hasher(); |
3216 | /// key.hash(&mut state); |
3217 | /// state.finish() |
3218 | /// } |
3219 | /// |
3220 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
3221 | /// let key = "a" ; |
3222 | /// let hash = compute_hash(map.hasher(), &key); |
3223 | /// let entry: RawEntryMut<&str, u32, _> = map.raw_entry_mut().from_hash(hash, |k| k == &key); |
3224 | /// entry.insert(key, 100); |
3225 | /// assert_eq!(map[&"a" ], 100); |
3226 | /// ``` |
3227 | #[cfg_attr (feature = "inline-more" , inline)] |
3228 | #[allow (clippy::wrong_self_convention)] |
3229 | pub fn from_hash<F>(self, hash: u64, is_match: F) -> RawEntryMut<'a, K, V, S, A> |
3230 | where |
3231 | for<'b> F: FnMut(&'b K) -> bool, |
3232 | { |
3233 | self.search(hash, is_match) |
3234 | } |
3235 | |
3236 | #[cfg_attr (feature = "inline-more" , inline)] |
3237 | fn search<F>(self, hash: u64, mut is_match: F) -> RawEntryMut<'a, K, V, S, A> |
3238 | where |
3239 | for<'b> F: FnMut(&'b K) -> bool, |
3240 | { |
3241 | match self.map.table.find(hash, |(k, _)| is_match(k)) { |
3242 | Some(elem) => RawEntryMut::Occupied(RawOccupiedEntryMut { |
3243 | elem, |
3244 | table: &mut self.map.table, |
3245 | hash_builder: &self.map.hash_builder, |
3246 | }), |
3247 | None => RawEntryMut::Vacant(RawVacantEntryMut { |
3248 | table: &mut self.map.table, |
3249 | hash_builder: &self.map.hash_builder, |
3250 | }), |
3251 | } |
3252 | } |
3253 | } |
3254 | |
3255 | impl<'a, K, V, S, A: Allocator> RawEntryBuilder<'a, K, V, S, A> { |
3256 | /// Access an immutable entry by key. |
3257 | /// |
3258 | /// # Examples |
3259 | /// |
3260 | /// ``` |
3261 | /// use hashbrown::HashMap; |
3262 | /// |
3263 | /// let map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3264 | /// let key = "a" ; |
3265 | /// assert_eq!(map.raw_entry().from_key(&key), Some((&"a" , &100))); |
3266 | /// ``` |
3267 | #[cfg_attr (feature = "inline-more" , inline)] |
3268 | #[allow (clippy::wrong_self_convention)] |
3269 | pub fn from_key<Q: ?Sized>(self, k: &Q) -> Option<(&'a K, &'a V)> |
3270 | where |
3271 | S: BuildHasher, |
3272 | Q: Hash + Equivalent<K>, |
3273 | { |
3274 | let hash = make_hash::<Q, S>(&self.map.hash_builder, k); |
3275 | self.from_key_hashed_nocheck(hash, k) |
3276 | } |
3277 | |
3278 | /// Access an immutable entry by a key and its hash. |
3279 | /// |
3280 | /// # Examples |
3281 | /// |
3282 | /// ``` |
3283 | /// use core::hash::{BuildHasher, Hash}; |
3284 | /// use hashbrown::HashMap; |
3285 | /// |
3286 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
3287 | /// use core::hash::Hasher; |
3288 | /// let mut state = hash_builder.build_hasher(); |
3289 | /// key.hash(&mut state); |
3290 | /// state.finish() |
3291 | /// } |
3292 | /// |
3293 | /// let map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3294 | /// let key = "a" ; |
3295 | /// let hash = compute_hash(map.hasher(), &key); |
3296 | /// assert_eq!(map.raw_entry().from_key_hashed_nocheck(hash, &key), Some((&"a" , &100))); |
3297 | /// ``` |
3298 | #[cfg_attr (feature = "inline-more" , inline)] |
3299 | #[allow (clippy::wrong_self_convention)] |
3300 | pub fn from_key_hashed_nocheck<Q: ?Sized>(self, hash: u64, k: &Q) -> Option<(&'a K, &'a V)> |
3301 | where |
3302 | Q: Equivalent<K>, |
3303 | { |
3304 | self.from_hash(hash, equivalent(k)) |
3305 | } |
3306 | |
3307 | #[cfg_attr (feature = "inline-more" , inline)] |
3308 | fn search<F>(self, hash: u64, mut is_match: F) -> Option<(&'a K, &'a V)> |
3309 | where |
3310 | F: FnMut(&K) -> bool, |
3311 | { |
3312 | match self.map.table.get(hash, |(k, _)| is_match(k)) { |
3313 | Some((key, value)) => Some((key, value)), |
3314 | None => None, |
3315 | } |
3316 | } |
3317 | |
3318 | /// Access an immutable entry by hash and matching function. |
3319 | /// |
3320 | /// # Examples |
3321 | /// |
3322 | /// ``` |
3323 | /// use core::hash::{BuildHasher, Hash}; |
3324 | /// use hashbrown::HashMap; |
3325 | /// |
3326 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
3327 | /// use core::hash::Hasher; |
3328 | /// let mut state = hash_builder.build_hasher(); |
3329 | /// key.hash(&mut state); |
3330 | /// state.finish() |
3331 | /// } |
3332 | /// |
3333 | /// let map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3334 | /// let key = "a" ; |
3335 | /// let hash = compute_hash(map.hasher(), &key); |
3336 | /// assert_eq!(map.raw_entry().from_hash(hash, |k| k == &key), Some((&"a" , &100))); |
3337 | /// ``` |
3338 | #[cfg_attr (feature = "inline-more" , inline)] |
3339 | #[allow (clippy::wrong_self_convention)] |
3340 | pub fn from_hash<F>(self, hash: u64, is_match: F) -> Option<(&'a K, &'a V)> |
3341 | where |
3342 | F: FnMut(&K) -> bool, |
3343 | { |
3344 | self.search(hash, is_match) |
3345 | } |
3346 | } |
3347 | |
3348 | impl<'a, K, V, S, A: Allocator> RawEntryMut<'a, K, V, S, A> { |
3349 | /// Sets the value of the entry, and returns a RawOccupiedEntryMut. |
3350 | /// |
3351 | /// # Examples |
3352 | /// |
3353 | /// ``` |
3354 | /// use hashbrown::HashMap; |
3355 | /// |
3356 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
3357 | /// let entry = map.raw_entry_mut().from_key("horseyland" ).insert("horseyland" , 37); |
3358 | /// |
3359 | /// assert_eq!(entry.remove_entry(), ("horseyland" , 37)); |
3360 | /// ``` |
3361 | #[cfg_attr (feature = "inline-more" , inline)] |
3362 | pub fn insert(self, key: K, value: V) -> RawOccupiedEntryMut<'a, K, V, S, A> |
3363 | where |
3364 | K: Hash, |
3365 | S: BuildHasher, |
3366 | { |
3367 | match self { |
3368 | RawEntryMut::Occupied(mut entry) => { |
3369 | entry.insert(value); |
3370 | entry |
3371 | } |
3372 | RawEntryMut::Vacant(entry) => entry.insert_entry(key, value), |
3373 | } |
3374 | } |
3375 | |
3376 | /// Ensures a value is in the entry by inserting the default if empty, and returns |
3377 | /// mutable references to the key and value in the entry. |
3378 | /// |
3379 | /// # Examples |
3380 | /// |
3381 | /// ``` |
3382 | /// use hashbrown::HashMap; |
3383 | /// |
3384 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
3385 | /// |
3386 | /// map.raw_entry_mut().from_key("poneyland" ).or_insert("poneyland" , 3); |
3387 | /// assert_eq!(map["poneyland" ], 3); |
3388 | /// |
3389 | /// *map.raw_entry_mut().from_key("poneyland" ).or_insert("poneyland" , 10).1 *= 2; |
3390 | /// assert_eq!(map["poneyland" ], 6); |
3391 | /// ``` |
3392 | #[cfg_attr (feature = "inline-more" , inline)] |
3393 | pub fn or_insert(self, default_key: K, default_val: V) -> (&'a mut K, &'a mut V) |
3394 | where |
3395 | K: Hash, |
3396 | S: BuildHasher, |
3397 | { |
3398 | match self { |
3399 | RawEntryMut::Occupied(entry) => entry.into_key_value(), |
3400 | RawEntryMut::Vacant(entry) => entry.insert(default_key, default_val), |
3401 | } |
3402 | } |
3403 | |
3404 | /// Ensures a value is in the entry by inserting the result of the default function if empty, |
3405 | /// and returns mutable references to the key and value in the entry. |
3406 | /// |
3407 | /// # Examples |
3408 | /// |
3409 | /// ``` |
3410 | /// use hashbrown::HashMap; |
3411 | /// |
3412 | /// let mut map: HashMap<&str, String> = HashMap::new(); |
3413 | /// |
3414 | /// map.raw_entry_mut().from_key("poneyland" ).or_insert_with(|| { |
3415 | /// ("poneyland" , "hoho" .to_string()) |
3416 | /// }); |
3417 | /// |
3418 | /// assert_eq!(map["poneyland" ], "hoho" .to_string()); |
3419 | /// ``` |
3420 | #[cfg_attr (feature = "inline-more" , inline)] |
3421 | pub fn or_insert_with<F>(self, default: F) -> (&'a mut K, &'a mut V) |
3422 | where |
3423 | F: FnOnce() -> (K, V), |
3424 | K: Hash, |
3425 | S: BuildHasher, |
3426 | { |
3427 | match self { |
3428 | RawEntryMut::Occupied(entry) => entry.into_key_value(), |
3429 | RawEntryMut::Vacant(entry) => { |
3430 | let (k, v) = default(); |
3431 | entry.insert(k, v) |
3432 | } |
3433 | } |
3434 | } |
3435 | |
3436 | /// Provides in-place mutable access to an occupied entry before any |
3437 | /// potential inserts into the map. |
3438 | /// |
3439 | /// # Examples |
3440 | /// |
3441 | /// ``` |
3442 | /// use hashbrown::HashMap; |
3443 | /// |
3444 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
3445 | /// |
3446 | /// map.raw_entry_mut() |
3447 | /// .from_key("poneyland" ) |
3448 | /// .and_modify(|_k, v| { *v += 1 }) |
3449 | /// .or_insert("poneyland" , 42); |
3450 | /// assert_eq!(map["poneyland" ], 42); |
3451 | /// |
3452 | /// map.raw_entry_mut() |
3453 | /// .from_key("poneyland" ) |
3454 | /// .and_modify(|_k, v| { *v += 1 }) |
3455 | /// .or_insert("poneyland" , 0); |
3456 | /// assert_eq!(map["poneyland" ], 43); |
3457 | /// ``` |
3458 | #[cfg_attr (feature = "inline-more" , inline)] |
3459 | pub fn and_modify<F>(self, f: F) -> Self |
3460 | where |
3461 | F: FnOnce(&mut K, &mut V), |
3462 | { |
3463 | match self { |
3464 | RawEntryMut::Occupied(mut entry) => { |
3465 | { |
3466 | let (k, v) = entry.get_key_value_mut(); |
3467 | f(k, v); |
3468 | } |
3469 | RawEntryMut::Occupied(entry) |
3470 | } |
3471 | RawEntryMut::Vacant(entry) => RawEntryMut::Vacant(entry), |
3472 | } |
3473 | } |
3474 | |
3475 | /// Provides shared access to the key and owned access to the value of |
3476 | /// an occupied entry and allows to replace or remove it based on the |
3477 | /// value of the returned option. |
3478 | /// |
3479 | /// # Examples |
3480 | /// |
3481 | /// ``` |
3482 | /// use hashbrown::HashMap; |
3483 | /// use hashbrown::hash_map::RawEntryMut; |
3484 | /// |
3485 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
3486 | /// |
3487 | /// let entry = map |
3488 | /// .raw_entry_mut() |
3489 | /// .from_key("poneyland" ) |
3490 | /// .and_replace_entry_with(|_k, _v| panic!()); |
3491 | /// |
3492 | /// match entry { |
3493 | /// RawEntryMut::Vacant(_) => {}, |
3494 | /// RawEntryMut::Occupied(_) => panic!(), |
3495 | /// } |
3496 | /// |
3497 | /// map.insert("poneyland" , 42); |
3498 | /// |
3499 | /// let entry = map |
3500 | /// .raw_entry_mut() |
3501 | /// .from_key("poneyland" ) |
3502 | /// .and_replace_entry_with(|k, v| { |
3503 | /// assert_eq!(k, &"poneyland" ); |
3504 | /// assert_eq!(v, 42); |
3505 | /// Some(v + 1) |
3506 | /// }); |
3507 | /// |
3508 | /// match entry { |
3509 | /// RawEntryMut::Occupied(e) => { |
3510 | /// assert_eq!(e.key(), &"poneyland" ); |
3511 | /// assert_eq!(e.get(), &43); |
3512 | /// }, |
3513 | /// RawEntryMut::Vacant(_) => panic!(), |
3514 | /// } |
3515 | /// |
3516 | /// assert_eq!(map["poneyland" ], 43); |
3517 | /// |
3518 | /// let entry = map |
3519 | /// .raw_entry_mut() |
3520 | /// .from_key("poneyland" ) |
3521 | /// .and_replace_entry_with(|_k, _v| None); |
3522 | /// |
3523 | /// match entry { |
3524 | /// RawEntryMut::Vacant(_) => {}, |
3525 | /// RawEntryMut::Occupied(_) => panic!(), |
3526 | /// } |
3527 | /// |
3528 | /// assert!(!map.contains_key("poneyland" )); |
3529 | /// ``` |
3530 | #[cfg_attr (feature = "inline-more" , inline)] |
3531 | pub fn and_replace_entry_with<F>(self, f: F) -> Self |
3532 | where |
3533 | F: FnOnce(&K, V) -> Option<V>, |
3534 | { |
3535 | match self { |
3536 | RawEntryMut::Occupied(entry) => entry.replace_entry_with(f), |
3537 | RawEntryMut::Vacant(_) => self, |
3538 | } |
3539 | } |
3540 | } |
3541 | |
3542 | impl<'a, K, V, S, A: Allocator> RawOccupiedEntryMut<'a, K, V, S, A> { |
3543 | /// Gets a reference to the key in the entry. |
3544 | /// |
3545 | /// # Examples |
3546 | /// |
3547 | /// ``` |
3548 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3549 | /// |
3550 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3551 | /// |
3552 | /// match map.raw_entry_mut().from_key(&"a" ) { |
3553 | /// RawEntryMut::Vacant(_) => panic!(), |
3554 | /// RawEntryMut::Occupied(o) => assert_eq!(o.key(), &"a" ) |
3555 | /// } |
3556 | /// ``` |
3557 | #[cfg_attr (feature = "inline-more" , inline)] |
3558 | pub fn key(&self) -> &K { |
3559 | unsafe { &self.elem.as_ref().0 } |
3560 | } |
3561 | |
3562 | /// Gets a mutable reference to the key in the entry. |
3563 | /// |
3564 | /// # Examples |
3565 | /// |
3566 | /// ``` |
3567 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3568 | /// use std::rc::Rc; |
3569 | /// |
3570 | /// let key_one = Rc::new("a" ); |
3571 | /// let key_two = Rc::new("a" ); |
3572 | /// |
3573 | /// let mut map: HashMap<Rc<&str>, u32> = HashMap::new(); |
3574 | /// map.insert(key_one.clone(), 10); |
3575 | /// |
3576 | /// assert_eq!(map[&key_one], 10); |
3577 | /// assert!(Rc::strong_count(&key_one) == 2 && Rc::strong_count(&key_two) == 1); |
3578 | /// |
3579 | /// match map.raw_entry_mut().from_key(&key_one) { |
3580 | /// RawEntryMut::Vacant(_) => panic!(), |
3581 | /// RawEntryMut::Occupied(mut o) => { |
3582 | /// *o.key_mut() = key_two.clone(); |
3583 | /// } |
3584 | /// } |
3585 | /// assert_eq!(map[&key_two], 10); |
3586 | /// assert!(Rc::strong_count(&key_one) == 1 && Rc::strong_count(&key_two) == 2); |
3587 | /// ``` |
3588 | #[cfg_attr (feature = "inline-more" , inline)] |
3589 | pub fn key_mut(&mut self) -> &mut K { |
3590 | unsafe { &mut self.elem.as_mut().0 } |
3591 | } |
3592 | |
3593 | /// Converts the entry into a mutable reference to the key in the entry |
3594 | /// with a lifetime bound to the map itself. |
3595 | /// |
3596 | /// # Examples |
3597 | /// |
3598 | /// ``` |
3599 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3600 | /// use std::rc::Rc; |
3601 | /// |
3602 | /// let key_one = Rc::new("a" ); |
3603 | /// let key_two = Rc::new("a" ); |
3604 | /// |
3605 | /// let mut map: HashMap<Rc<&str>, u32> = HashMap::new(); |
3606 | /// map.insert(key_one.clone(), 10); |
3607 | /// |
3608 | /// assert_eq!(map[&key_one], 10); |
3609 | /// assert!(Rc::strong_count(&key_one) == 2 && Rc::strong_count(&key_two) == 1); |
3610 | /// |
3611 | /// let inside_key: &mut Rc<&str>; |
3612 | /// |
3613 | /// match map.raw_entry_mut().from_key(&key_one) { |
3614 | /// RawEntryMut::Vacant(_) => panic!(), |
3615 | /// RawEntryMut::Occupied(o) => inside_key = o.into_key(), |
3616 | /// } |
3617 | /// *inside_key = key_two.clone(); |
3618 | /// |
3619 | /// assert_eq!(map[&key_two], 10); |
3620 | /// assert!(Rc::strong_count(&key_one) == 1 && Rc::strong_count(&key_two) == 2); |
3621 | /// ``` |
3622 | #[cfg_attr (feature = "inline-more" , inline)] |
3623 | pub fn into_key(self) -> &'a mut K { |
3624 | unsafe { &mut self.elem.as_mut().0 } |
3625 | } |
3626 | |
3627 | /// Gets a reference to the value in the entry. |
3628 | /// |
3629 | /// # Examples |
3630 | /// |
3631 | /// ``` |
3632 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3633 | /// |
3634 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3635 | /// |
3636 | /// match map.raw_entry_mut().from_key(&"a" ) { |
3637 | /// RawEntryMut::Vacant(_) => panic!(), |
3638 | /// RawEntryMut::Occupied(o) => assert_eq!(o.get(), &100), |
3639 | /// } |
3640 | /// ``` |
3641 | #[cfg_attr (feature = "inline-more" , inline)] |
3642 | pub fn get(&self) -> &V { |
3643 | unsafe { &self.elem.as_ref().1 } |
3644 | } |
3645 | |
3646 | /// Converts the OccupiedEntry into a mutable reference to the value in the entry |
3647 | /// with a lifetime bound to the map itself. |
3648 | /// |
3649 | /// # Examples |
3650 | /// |
3651 | /// ``` |
3652 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3653 | /// |
3654 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3655 | /// |
3656 | /// let value: &mut u32; |
3657 | /// |
3658 | /// match map.raw_entry_mut().from_key(&"a" ) { |
3659 | /// RawEntryMut::Vacant(_) => panic!(), |
3660 | /// RawEntryMut::Occupied(o) => value = o.into_mut(), |
3661 | /// } |
3662 | /// *value += 900; |
3663 | /// |
3664 | /// assert_eq!(map[&"a" ], 1000); |
3665 | /// ``` |
3666 | #[cfg_attr (feature = "inline-more" , inline)] |
3667 | pub fn into_mut(self) -> &'a mut V { |
3668 | unsafe { &mut self.elem.as_mut().1 } |
3669 | } |
3670 | |
3671 | /// Gets a mutable reference to the value in the entry. |
3672 | /// |
3673 | /// # Examples |
3674 | /// |
3675 | /// ``` |
3676 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3677 | /// |
3678 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3679 | /// |
3680 | /// match map.raw_entry_mut().from_key(&"a" ) { |
3681 | /// RawEntryMut::Vacant(_) => panic!(), |
3682 | /// RawEntryMut::Occupied(mut o) => *o.get_mut() += 900, |
3683 | /// } |
3684 | /// |
3685 | /// assert_eq!(map[&"a" ], 1000); |
3686 | /// ``` |
3687 | #[cfg_attr (feature = "inline-more" , inline)] |
3688 | pub fn get_mut(&mut self) -> &mut V { |
3689 | unsafe { &mut self.elem.as_mut().1 } |
3690 | } |
3691 | |
3692 | /// Gets a reference to the key and value in the entry. |
3693 | /// |
3694 | /// # Examples |
3695 | /// |
3696 | /// ``` |
3697 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3698 | /// |
3699 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3700 | /// |
3701 | /// match map.raw_entry_mut().from_key(&"a" ) { |
3702 | /// RawEntryMut::Vacant(_) => panic!(), |
3703 | /// RawEntryMut::Occupied(o) => assert_eq!(o.get_key_value(), (&"a" , &100)), |
3704 | /// } |
3705 | /// ``` |
3706 | #[cfg_attr (feature = "inline-more" , inline)] |
3707 | pub fn get_key_value(&self) -> (&K, &V) { |
3708 | unsafe { |
3709 | let (key, value) = self.elem.as_ref(); |
3710 | (key, value) |
3711 | } |
3712 | } |
3713 | |
3714 | /// Gets a mutable reference to the key and value in the entry. |
3715 | /// |
3716 | /// # Examples |
3717 | /// |
3718 | /// ``` |
3719 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3720 | /// use std::rc::Rc; |
3721 | /// |
3722 | /// let key_one = Rc::new("a" ); |
3723 | /// let key_two = Rc::new("a" ); |
3724 | /// |
3725 | /// let mut map: HashMap<Rc<&str>, u32> = HashMap::new(); |
3726 | /// map.insert(key_one.clone(), 10); |
3727 | /// |
3728 | /// assert_eq!(map[&key_one], 10); |
3729 | /// assert!(Rc::strong_count(&key_one) == 2 && Rc::strong_count(&key_two) == 1); |
3730 | /// |
3731 | /// match map.raw_entry_mut().from_key(&key_one) { |
3732 | /// RawEntryMut::Vacant(_) => panic!(), |
3733 | /// RawEntryMut::Occupied(mut o) => { |
3734 | /// let (inside_key, inside_value) = o.get_key_value_mut(); |
3735 | /// *inside_key = key_two.clone(); |
3736 | /// *inside_value = 100; |
3737 | /// } |
3738 | /// } |
3739 | /// assert_eq!(map[&key_two], 100); |
3740 | /// assert!(Rc::strong_count(&key_one) == 1 && Rc::strong_count(&key_two) == 2); |
3741 | /// ``` |
3742 | #[cfg_attr (feature = "inline-more" , inline)] |
3743 | pub fn get_key_value_mut(&mut self) -> (&mut K, &mut V) { |
3744 | unsafe { |
3745 | let &mut (ref mut key, ref mut value) = self.elem.as_mut(); |
3746 | (key, value) |
3747 | } |
3748 | } |
3749 | |
3750 | /// Converts the OccupiedEntry into a mutable reference to the key and value in the entry |
3751 | /// with a lifetime bound to the map itself. |
3752 | /// |
3753 | /// # Examples |
3754 | /// |
3755 | /// ``` |
3756 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3757 | /// use std::rc::Rc; |
3758 | /// |
3759 | /// let key_one = Rc::new("a" ); |
3760 | /// let key_two = Rc::new("a" ); |
3761 | /// |
3762 | /// let mut map: HashMap<Rc<&str>, u32> = HashMap::new(); |
3763 | /// map.insert(key_one.clone(), 10); |
3764 | /// |
3765 | /// assert_eq!(map[&key_one], 10); |
3766 | /// assert!(Rc::strong_count(&key_one) == 2 && Rc::strong_count(&key_two) == 1); |
3767 | /// |
3768 | /// let inside_key: &mut Rc<&str>; |
3769 | /// let inside_value: &mut u32; |
3770 | /// match map.raw_entry_mut().from_key(&key_one) { |
3771 | /// RawEntryMut::Vacant(_) => panic!(), |
3772 | /// RawEntryMut::Occupied(o) => { |
3773 | /// let tuple = o.into_key_value(); |
3774 | /// inside_key = tuple.0; |
3775 | /// inside_value = tuple.1; |
3776 | /// } |
3777 | /// } |
3778 | /// *inside_key = key_two.clone(); |
3779 | /// *inside_value = 100; |
3780 | /// assert_eq!(map[&key_two], 100); |
3781 | /// assert!(Rc::strong_count(&key_one) == 1 && Rc::strong_count(&key_two) == 2); |
3782 | /// ``` |
3783 | #[cfg_attr (feature = "inline-more" , inline)] |
3784 | pub fn into_key_value(self) -> (&'a mut K, &'a mut V) { |
3785 | unsafe { |
3786 | let &mut (ref mut key, ref mut value) = self.elem.as_mut(); |
3787 | (key, value) |
3788 | } |
3789 | } |
3790 | |
3791 | /// Sets the value of the entry, and returns the entry's old value. |
3792 | /// |
3793 | /// # Examples |
3794 | /// |
3795 | /// ``` |
3796 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3797 | /// |
3798 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3799 | /// |
3800 | /// match map.raw_entry_mut().from_key(&"a" ) { |
3801 | /// RawEntryMut::Vacant(_) => panic!(), |
3802 | /// RawEntryMut::Occupied(mut o) => assert_eq!(o.insert(1000), 100), |
3803 | /// } |
3804 | /// |
3805 | /// assert_eq!(map[&"a" ], 1000); |
3806 | /// ``` |
3807 | #[cfg_attr (feature = "inline-more" , inline)] |
3808 | pub fn insert(&mut self, value: V) -> V { |
3809 | mem::replace(self.get_mut(), value) |
3810 | } |
3811 | |
3812 | /// Sets the value of the entry, and returns the entry's old value. |
3813 | /// |
3814 | /// # Examples |
3815 | /// |
3816 | /// ``` |
3817 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3818 | /// use std::rc::Rc; |
3819 | /// |
3820 | /// let key_one = Rc::new("a" ); |
3821 | /// let key_two = Rc::new("a" ); |
3822 | /// |
3823 | /// let mut map: HashMap<Rc<&str>, u32> = HashMap::new(); |
3824 | /// map.insert(key_one.clone(), 10); |
3825 | /// |
3826 | /// assert_eq!(map[&key_one], 10); |
3827 | /// assert!(Rc::strong_count(&key_one) == 2 && Rc::strong_count(&key_two) == 1); |
3828 | /// |
3829 | /// match map.raw_entry_mut().from_key(&key_one) { |
3830 | /// RawEntryMut::Vacant(_) => panic!(), |
3831 | /// RawEntryMut::Occupied(mut o) => { |
3832 | /// let old_key = o.insert_key(key_two.clone()); |
3833 | /// assert!(Rc::ptr_eq(&old_key, &key_one)); |
3834 | /// } |
3835 | /// } |
3836 | /// assert_eq!(map[&key_two], 10); |
3837 | /// assert!(Rc::strong_count(&key_one) == 1 && Rc::strong_count(&key_two) == 2); |
3838 | /// ``` |
3839 | #[cfg_attr (feature = "inline-more" , inline)] |
3840 | pub fn insert_key(&mut self, key: K) -> K { |
3841 | mem::replace(self.key_mut(), key) |
3842 | } |
3843 | |
3844 | /// Takes the value out of the entry, and returns it. |
3845 | /// |
3846 | /// # Examples |
3847 | /// |
3848 | /// ``` |
3849 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3850 | /// |
3851 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3852 | /// |
3853 | /// match map.raw_entry_mut().from_key(&"a" ) { |
3854 | /// RawEntryMut::Vacant(_) => panic!(), |
3855 | /// RawEntryMut::Occupied(o) => assert_eq!(o.remove(), 100), |
3856 | /// } |
3857 | /// assert_eq!(map.get(&"a" ), None); |
3858 | /// ``` |
3859 | #[cfg_attr (feature = "inline-more" , inline)] |
3860 | pub fn remove(self) -> V { |
3861 | self.remove_entry().1 |
3862 | } |
3863 | |
3864 | /// Take the ownership of the key and value from the map. |
3865 | /// |
3866 | /// # Examples |
3867 | /// |
3868 | /// ``` |
3869 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3870 | /// |
3871 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3872 | /// |
3873 | /// match map.raw_entry_mut().from_key(&"a" ) { |
3874 | /// RawEntryMut::Vacant(_) => panic!(), |
3875 | /// RawEntryMut::Occupied(o) => assert_eq!(o.remove_entry(), ("a" , 100)), |
3876 | /// } |
3877 | /// assert_eq!(map.get(&"a" ), None); |
3878 | /// ``` |
3879 | #[cfg_attr (feature = "inline-more" , inline)] |
3880 | pub fn remove_entry(self) -> (K, V) { |
3881 | unsafe { self.table.remove(self.elem).0 } |
3882 | } |
3883 | |
3884 | /// Provides shared access to the key and owned access to the value of |
3885 | /// the entry and allows to replace or remove it based on the |
3886 | /// value of the returned option. |
3887 | /// |
3888 | /// # Examples |
3889 | /// |
3890 | /// ``` |
3891 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3892 | /// |
3893 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3894 | /// |
3895 | /// let raw_entry = match map.raw_entry_mut().from_key(&"a" ) { |
3896 | /// RawEntryMut::Vacant(_) => panic!(), |
3897 | /// RawEntryMut::Occupied(o) => o.replace_entry_with(|k, v| { |
3898 | /// assert_eq!(k, &"a" ); |
3899 | /// assert_eq!(v, 100); |
3900 | /// Some(v + 900) |
3901 | /// }), |
3902 | /// }; |
3903 | /// let raw_entry = match raw_entry { |
3904 | /// RawEntryMut::Vacant(_) => panic!(), |
3905 | /// RawEntryMut::Occupied(o) => o.replace_entry_with(|k, v| { |
3906 | /// assert_eq!(k, &"a" ); |
3907 | /// assert_eq!(v, 1000); |
3908 | /// None |
3909 | /// }), |
3910 | /// }; |
3911 | /// match raw_entry { |
3912 | /// RawEntryMut::Vacant(_) => { }, |
3913 | /// RawEntryMut::Occupied(_) => panic!(), |
3914 | /// }; |
3915 | /// assert_eq!(map.get(&"a" ), None); |
3916 | /// ``` |
3917 | #[cfg_attr (feature = "inline-more" , inline)] |
3918 | pub fn replace_entry_with<F>(self, f: F) -> RawEntryMut<'a, K, V, S, A> |
3919 | where |
3920 | F: FnOnce(&K, V) -> Option<V>, |
3921 | { |
3922 | unsafe { |
3923 | let still_occupied = self |
3924 | .table |
3925 | .replace_bucket_with(self.elem.clone(), |(key, value)| { |
3926 | f(&key, value).map(|new_value| (key, new_value)) |
3927 | }); |
3928 | |
3929 | if still_occupied { |
3930 | RawEntryMut::Occupied(self) |
3931 | } else { |
3932 | RawEntryMut::Vacant(RawVacantEntryMut { |
3933 | table: self.table, |
3934 | hash_builder: self.hash_builder, |
3935 | }) |
3936 | } |
3937 | } |
3938 | } |
3939 | } |
3940 | |
3941 | impl<'a, K, V, S, A: Allocator> RawVacantEntryMut<'a, K, V, S, A> { |
3942 | /// Sets the value of the entry with the VacantEntry's key, |
3943 | /// and returns a mutable reference to it. |
3944 | /// |
3945 | /// # Examples |
3946 | /// |
3947 | /// ``` |
3948 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3949 | /// |
3950 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3951 | /// |
3952 | /// match map.raw_entry_mut().from_key(&"c" ) { |
3953 | /// RawEntryMut::Occupied(_) => panic!(), |
3954 | /// RawEntryMut::Vacant(v) => assert_eq!(v.insert("c" , 300), (&mut "c" , &mut 300)), |
3955 | /// } |
3956 | /// |
3957 | /// assert_eq!(map[&"c" ], 300); |
3958 | /// ``` |
3959 | #[cfg_attr (feature = "inline-more" , inline)] |
3960 | pub fn insert(self, key: K, value: V) -> (&'a mut K, &'a mut V) |
3961 | where |
3962 | K: Hash, |
3963 | S: BuildHasher, |
3964 | { |
3965 | let hash = make_hash::<K, S>(self.hash_builder, &key); |
3966 | self.insert_hashed_nocheck(hash, key, value) |
3967 | } |
3968 | |
3969 | /// Sets the value of the entry with the VacantEntry's key, |
3970 | /// and returns a mutable reference to it. |
3971 | /// |
3972 | /// # Examples |
3973 | /// |
3974 | /// ``` |
3975 | /// use core::hash::{BuildHasher, Hash}; |
3976 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
3977 | /// |
3978 | /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 { |
3979 | /// use core::hash::Hasher; |
3980 | /// let mut state = hash_builder.build_hasher(); |
3981 | /// key.hash(&mut state); |
3982 | /// state.finish() |
3983 | /// } |
3984 | /// |
3985 | /// let mut map: HashMap<&str, u32> = [("a" , 100), ("b" , 200)].into(); |
3986 | /// let key = "c" ; |
3987 | /// let hash = compute_hash(map.hasher(), &key); |
3988 | /// |
3989 | /// match map.raw_entry_mut().from_key_hashed_nocheck(hash, &key) { |
3990 | /// RawEntryMut::Occupied(_) => panic!(), |
3991 | /// RawEntryMut::Vacant(v) => assert_eq!( |
3992 | /// v.insert_hashed_nocheck(hash, key, 300), |
3993 | /// (&mut "c" , &mut 300) |
3994 | /// ), |
3995 | /// } |
3996 | /// |
3997 | /// assert_eq!(map[&"c" ], 300); |
3998 | /// ``` |
3999 | #[cfg_attr (feature = "inline-more" , inline)] |
4000 | #[allow (clippy::shadow_unrelated)] |
4001 | pub fn insert_hashed_nocheck(self, hash: u64, key: K, value: V) -> (&'a mut K, &'a mut V) |
4002 | where |
4003 | K: Hash, |
4004 | S: BuildHasher, |
4005 | { |
4006 | let &mut (ref mut k, ref mut v) = self.table.insert_entry( |
4007 | hash, |
4008 | (key, value), |
4009 | make_hasher::<_, V, S>(self.hash_builder), |
4010 | ); |
4011 | (k, v) |
4012 | } |
4013 | |
4014 | /// Set the value of an entry with a custom hasher function. |
4015 | /// |
4016 | /// # Examples |
4017 | /// |
4018 | /// ``` |
4019 | /// use core::hash::{BuildHasher, Hash}; |
4020 | /// use hashbrown::hash_map::{HashMap, RawEntryMut}; |
4021 | /// |
4022 | /// fn make_hasher<K, S>(hash_builder: &S) -> impl Fn(&K) -> u64 + '_ |
4023 | /// where |
4024 | /// K: Hash + ?Sized, |
4025 | /// S: BuildHasher, |
4026 | /// { |
4027 | /// move |key: &K| { |
4028 | /// use core::hash::Hasher; |
4029 | /// let mut state = hash_builder.build_hasher(); |
4030 | /// key.hash(&mut state); |
4031 | /// state.finish() |
4032 | /// } |
4033 | /// } |
4034 | /// |
4035 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
4036 | /// let key = "a" ; |
4037 | /// let hash_builder = map.hasher().clone(); |
4038 | /// let hash = make_hasher(&hash_builder)(&key); |
4039 | /// |
4040 | /// match map.raw_entry_mut().from_hash(hash, |q| q == &key) { |
4041 | /// RawEntryMut::Occupied(_) => panic!(), |
4042 | /// RawEntryMut::Vacant(v) => assert_eq!( |
4043 | /// v.insert_with_hasher(hash, key, 100, make_hasher(&hash_builder)), |
4044 | /// (&mut "a" , &mut 100) |
4045 | /// ), |
4046 | /// } |
4047 | /// map.extend([("b" , 200), ("c" , 300), ("d" , 400), ("e" , 500), ("f" , 600)]); |
4048 | /// assert_eq!(map[&"a" ], 100); |
4049 | /// ``` |
4050 | #[cfg_attr (feature = "inline-more" , inline)] |
4051 | pub fn insert_with_hasher<H>( |
4052 | self, |
4053 | hash: u64, |
4054 | key: K, |
4055 | value: V, |
4056 | hasher: H, |
4057 | ) -> (&'a mut K, &'a mut V) |
4058 | where |
4059 | H: Fn(&K) -> u64, |
4060 | { |
4061 | let &mut (ref mut k, ref mut v) = self |
4062 | .table |
4063 | .insert_entry(hash, (key, value), |x| hasher(&x.0)); |
4064 | (k, v) |
4065 | } |
4066 | |
4067 | #[cfg_attr (feature = "inline-more" , inline)] |
4068 | fn insert_entry(self, key: K, value: V) -> RawOccupiedEntryMut<'a, K, V, S, A> |
4069 | where |
4070 | K: Hash, |
4071 | S: BuildHasher, |
4072 | { |
4073 | let hash = make_hash::<K, S>(self.hash_builder, &key); |
4074 | let elem = self.table.insert( |
4075 | hash, |
4076 | (key, value), |
4077 | make_hasher::<_, V, S>(self.hash_builder), |
4078 | ); |
4079 | RawOccupiedEntryMut { |
4080 | elem, |
4081 | table: self.table, |
4082 | hash_builder: self.hash_builder, |
4083 | } |
4084 | } |
4085 | } |
4086 | |
4087 | impl<K, V, S, A: Allocator> Debug for RawEntryBuilderMut<'_, K, V, S, A> { |
4088 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4089 | f.debug_struct("RawEntryBuilder" ).finish() |
4090 | } |
4091 | } |
4092 | |
4093 | impl<K: Debug, V: Debug, S, A: Allocator> Debug for RawEntryMut<'_, K, V, S, A> { |
4094 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4095 | match *self { |
4096 | RawEntryMut::Vacant(ref v: &RawVacantEntryMut<'_, K, …, …, …>) => f.debug_tuple("RawEntry" ).field(v).finish(), |
4097 | RawEntryMut::Occupied(ref o: &RawOccupiedEntryMut<'_, …, …, …, …>) => f.debug_tuple("RawEntry" ).field(o).finish(), |
4098 | } |
4099 | } |
4100 | } |
4101 | |
4102 | impl<K: Debug, V: Debug, S, A: Allocator> Debug for RawOccupiedEntryMut<'_, K, V, S, A> { |
4103 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4104 | f.debug_struct("RawOccupiedEntryMut" ) |
4105 | .field("key" , self.key()) |
4106 | .field("value" , self.get()) |
4107 | .finish() |
4108 | } |
4109 | } |
4110 | |
4111 | impl<K, V, S, A: Allocator> Debug for RawVacantEntryMut<'_, K, V, S, A> { |
4112 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4113 | f.debug_struct("RawVacantEntryMut" ).finish() |
4114 | } |
4115 | } |
4116 | |
4117 | impl<K, V, S, A: Allocator> Debug for RawEntryBuilder<'_, K, V, S, A> { |
4118 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4119 | f.debug_struct("RawEntryBuilder" ).finish() |
4120 | } |
4121 | } |
4122 | |
4123 | /// A view into a single entry in a map, which may either be vacant or occupied. |
4124 | /// |
4125 | /// This `enum` is constructed from the [`entry`] method on [`HashMap`]. |
4126 | /// |
4127 | /// [`HashMap`]: struct.HashMap.html |
4128 | /// [`entry`]: struct.HashMap.html#method.entry |
4129 | /// |
4130 | /// # Examples |
4131 | /// |
4132 | /// ``` |
4133 | /// use hashbrown::hash_map::{Entry, HashMap, OccupiedEntry}; |
4134 | /// |
4135 | /// let mut map = HashMap::new(); |
4136 | /// map.extend([("a" , 10), ("b" , 20), ("c" , 30)]); |
4137 | /// assert_eq!(map.len(), 3); |
4138 | /// |
4139 | /// // Existing key (insert) |
4140 | /// let entry: Entry<_, _, _> = map.entry("a" ); |
4141 | /// let _raw_o: OccupiedEntry<_, _, _> = entry.insert(1); |
4142 | /// assert_eq!(map.len(), 3); |
4143 | /// // Nonexistent key (insert) |
4144 | /// map.entry("d" ).insert(4); |
4145 | /// |
4146 | /// // Existing key (or_insert) |
4147 | /// let v = map.entry("b" ).or_insert(2); |
4148 | /// assert_eq!(std::mem::replace(v, 2), 20); |
4149 | /// // Nonexistent key (or_insert) |
4150 | /// map.entry("e" ).or_insert(5); |
4151 | /// |
4152 | /// // Existing key (or_insert_with) |
4153 | /// let v = map.entry("c" ).or_insert_with(|| 3); |
4154 | /// assert_eq!(std::mem::replace(v, 3), 30); |
4155 | /// // Nonexistent key (or_insert_with) |
4156 | /// map.entry("f" ).or_insert_with(|| 6); |
4157 | /// |
4158 | /// println!("Our HashMap: {:?}" , map); |
4159 | /// |
4160 | /// let mut vec: Vec<_> = map.iter().map(|(&k, &v)| (k, v)).collect(); |
4161 | /// // The `Iter` iterator produces items in arbitrary order, so the |
4162 | /// // items must be sorted to test them against a sorted array. |
4163 | /// vec.sort_unstable(); |
4164 | /// assert_eq!(vec, [("a" , 1), ("b" , 2), ("c" , 3), ("d" , 4), ("e" , 5), ("f" , 6)]); |
4165 | /// ``` |
4166 | pub enum Entry<'a, K, V, S, A = Global> |
4167 | where |
4168 | A: Allocator, |
4169 | { |
4170 | /// An occupied entry. |
4171 | /// |
4172 | /// # Examples |
4173 | /// |
4174 | /// ``` |
4175 | /// use hashbrown::hash_map::{Entry, HashMap}; |
4176 | /// let mut map: HashMap<_, _> = [("a" , 100), ("b" , 200)].into(); |
4177 | /// |
4178 | /// match map.entry("a" ) { |
4179 | /// Entry::Vacant(_) => unreachable!(), |
4180 | /// Entry::Occupied(_) => { } |
4181 | /// } |
4182 | /// ``` |
4183 | Occupied(OccupiedEntry<'a, K, V, S, A>), |
4184 | |
4185 | /// A vacant entry. |
4186 | /// |
4187 | /// # Examples |
4188 | /// |
4189 | /// ``` |
4190 | /// use hashbrown::hash_map::{Entry, HashMap}; |
4191 | /// let mut map: HashMap<&str, i32> = HashMap::new(); |
4192 | /// |
4193 | /// match map.entry("a" ) { |
4194 | /// Entry::Occupied(_) => unreachable!(), |
4195 | /// Entry::Vacant(_) => { } |
4196 | /// } |
4197 | /// ``` |
4198 | Vacant(VacantEntry<'a, K, V, S, A>), |
4199 | } |
4200 | |
4201 | impl<K: Debug, V: Debug, S, A: Allocator> Debug for Entry<'_, K, V, S, A> { |
4202 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4203 | match *self { |
4204 | Entry::Vacant(ref v: &VacantEntry<'_, K, V, S, …>) => f.debug_tuple("Entry" ).field(v).finish(), |
4205 | Entry::Occupied(ref o: &OccupiedEntry<'_, K, V, …, …>) => f.debug_tuple("Entry" ).field(o).finish(), |
4206 | } |
4207 | } |
4208 | } |
4209 | |
4210 | /// A view into an occupied entry in a `HashMap`. |
4211 | /// It is part of the [`Entry`] enum. |
4212 | /// |
4213 | /// [`Entry`]: enum.Entry.html |
4214 | /// |
4215 | /// # Examples |
4216 | /// |
4217 | /// ``` |
4218 | /// use hashbrown::hash_map::{Entry, HashMap, OccupiedEntry}; |
4219 | /// |
4220 | /// let mut map = HashMap::new(); |
4221 | /// map.extend([("a" , 10), ("b" , 20), ("c" , 30)]); |
4222 | /// |
4223 | /// let _entry_o: OccupiedEntry<_, _, _> = map.entry("a" ).insert(100); |
4224 | /// assert_eq!(map.len(), 3); |
4225 | /// |
4226 | /// // Existing key (insert and update) |
4227 | /// match map.entry("a" ) { |
4228 | /// Entry::Vacant(_) => unreachable!(), |
4229 | /// Entry::Occupied(mut view) => { |
4230 | /// assert_eq!(view.get(), &100); |
4231 | /// let v = view.get_mut(); |
4232 | /// *v *= 10; |
4233 | /// assert_eq!(view.insert(1111), 1000); |
4234 | /// } |
4235 | /// } |
4236 | /// |
4237 | /// assert_eq!(map[&"a" ], 1111); |
4238 | /// assert_eq!(map.len(), 3); |
4239 | /// |
4240 | /// // Existing key (take) |
4241 | /// match map.entry("c" ) { |
4242 | /// Entry::Vacant(_) => unreachable!(), |
4243 | /// Entry::Occupied(view) => { |
4244 | /// assert_eq!(view.remove_entry(), ("c" , 30)); |
4245 | /// } |
4246 | /// } |
4247 | /// assert_eq!(map.get(&"c" ), None); |
4248 | /// assert_eq!(map.len(), 2); |
4249 | /// ``` |
4250 | pub struct OccupiedEntry<'a, K, V, S = DefaultHashBuilder, A: Allocator = Global> { |
4251 | hash: u64, |
4252 | key: Option<K>, |
4253 | elem: Bucket<(K, V)>, |
4254 | table: &'a mut HashMap<K, V, S, A>, |
4255 | } |
4256 | |
4257 | unsafe impl<K, V, S, A> Send for OccupiedEntry<'_, K, V, S, A> |
4258 | where |
4259 | K: Send, |
4260 | V: Send, |
4261 | S: Send, |
4262 | A: Send + Allocator, |
4263 | { |
4264 | } |
4265 | unsafe impl<K, V, S, A> Sync for OccupiedEntry<'_, K, V, S, A> |
4266 | where |
4267 | K: Sync, |
4268 | V: Sync, |
4269 | S: Sync, |
4270 | A: Sync + Allocator, |
4271 | { |
4272 | } |
4273 | |
4274 | impl<K: Debug, V: Debug, S, A: Allocator> Debug for OccupiedEntry<'_, K, V, S, A> { |
4275 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4276 | f.debug_struct("OccupiedEntry" ) |
4277 | .field("key" , self.key()) |
4278 | .field("value" , self.get()) |
4279 | .finish() |
4280 | } |
4281 | } |
4282 | |
4283 | /// A view into a vacant entry in a `HashMap`. |
4284 | /// It is part of the [`Entry`] enum. |
4285 | /// |
4286 | /// [`Entry`]: enum.Entry.html |
4287 | /// |
4288 | /// # Examples |
4289 | /// |
4290 | /// ``` |
4291 | /// use hashbrown::hash_map::{Entry, HashMap, VacantEntry}; |
4292 | /// |
4293 | /// let mut map = HashMap::<&str, i32>::new(); |
4294 | /// |
4295 | /// let entry_v: VacantEntry<_, _, _> = match map.entry("a" ) { |
4296 | /// Entry::Vacant(view) => view, |
4297 | /// Entry::Occupied(_) => unreachable!(), |
4298 | /// }; |
4299 | /// entry_v.insert(10); |
4300 | /// assert!(map[&"a" ] == 10 && map.len() == 1); |
4301 | /// |
4302 | /// // Nonexistent key (insert and update) |
4303 | /// match map.entry("b" ) { |
4304 | /// Entry::Occupied(_) => unreachable!(), |
4305 | /// Entry::Vacant(view) => { |
4306 | /// let value = view.insert(2); |
4307 | /// assert_eq!(*value, 2); |
4308 | /// *value = 20; |
4309 | /// } |
4310 | /// } |
4311 | /// assert!(map[&"b" ] == 20 && map.len() == 2); |
4312 | /// ``` |
4313 | pub struct VacantEntry<'a, K, V, S = DefaultHashBuilder, A: Allocator = Global> { |
4314 | hash: u64, |
4315 | key: K, |
4316 | table: &'a mut HashMap<K, V, S, A>, |
4317 | } |
4318 | |
4319 | impl<K: Debug, V, S, A: Allocator> Debug for VacantEntry<'_, K, V, S, A> { |
4320 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4321 | f.debug_tuple("VacantEntry" ).field(self.key()).finish() |
4322 | } |
4323 | } |
4324 | |
4325 | /// A view into a single entry in a map, which may either be vacant or occupied, |
4326 | /// with any borrowed form of the map's key type. |
4327 | /// |
4328 | /// |
4329 | /// This `enum` is constructed from the [`entry_ref`] method on [`HashMap`]. |
4330 | /// |
4331 | /// [`Hash`] and [`Eq`] on the borrowed form of the map's key type *must* match those |
4332 | /// for the key type. It also require that key may be constructed from the borrowed |
4333 | /// form through the [`From`] trait. |
4334 | /// |
4335 | /// [`HashMap`]: struct.HashMap.html |
4336 | /// [`entry_ref`]: struct.HashMap.html#method.entry_ref |
4337 | /// [`Eq`]: https://doc.rust-lang.org/std/cmp/trait.Eq.html |
4338 | /// [`Hash`]: https://doc.rust-lang.org/std/hash/trait.Hash.html |
4339 | /// [`From`]: https://doc.rust-lang.org/std/convert/trait.From.html |
4340 | /// |
4341 | /// # Examples |
4342 | /// |
4343 | /// ``` |
4344 | /// use hashbrown::hash_map::{EntryRef, HashMap, OccupiedEntryRef}; |
4345 | /// |
4346 | /// let mut map = HashMap::new(); |
4347 | /// map.extend([("a" .to_owned(), 10), ("b" .into(), 20), ("c" .into(), 30)]); |
4348 | /// assert_eq!(map.len(), 3); |
4349 | /// |
4350 | /// // Existing key (insert) |
4351 | /// let key = String::from("a" ); |
4352 | /// let entry: EntryRef<_, _, _, _> = map.entry_ref(&key); |
4353 | /// let _raw_o: OccupiedEntryRef<_, _, _, _> = entry.insert(1); |
4354 | /// assert_eq!(map.len(), 3); |
4355 | /// // Nonexistent key (insert) |
4356 | /// map.entry_ref("d" ).insert(4); |
4357 | /// |
4358 | /// // Existing key (or_insert) |
4359 | /// let v = map.entry_ref("b" ).or_insert(2); |
4360 | /// assert_eq!(std::mem::replace(v, 2), 20); |
4361 | /// // Nonexistent key (or_insert) |
4362 | /// map.entry_ref("e" ).or_insert(5); |
4363 | /// |
4364 | /// // Existing key (or_insert_with) |
4365 | /// let v = map.entry_ref("c" ).or_insert_with(|| 3); |
4366 | /// assert_eq!(std::mem::replace(v, 3), 30); |
4367 | /// // Nonexistent key (or_insert_with) |
4368 | /// map.entry_ref("f" ).or_insert_with(|| 6); |
4369 | /// |
4370 | /// println!("Our HashMap: {:?}" , map); |
4371 | /// |
4372 | /// for (key, value) in ["a" , "b" , "c" , "d" , "e" , "f" ].into_iter().zip(1..=6) { |
4373 | /// assert_eq!(map[key], value) |
4374 | /// } |
4375 | /// assert_eq!(map.len(), 6); |
4376 | /// ``` |
4377 | pub enum EntryRef<'a, 'b, K, Q: ?Sized, V, S, A = Global> |
4378 | where |
4379 | A: Allocator, |
4380 | { |
4381 | /// An occupied entry. |
4382 | /// |
4383 | /// # Examples |
4384 | /// |
4385 | /// ``` |
4386 | /// use hashbrown::hash_map::{EntryRef, HashMap}; |
4387 | /// let mut map: HashMap<_, _> = [("a" .to_owned(), 100), ("b" .into(), 200)].into(); |
4388 | /// |
4389 | /// match map.entry_ref("a" ) { |
4390 | /// EntryRef::Vacant(_) => unreachable!(), |
4391 | /// EntryRef::Occupied(_) => { } |
4392 | /// } |
4393 | /// ``` |
4394 | Occupied(OccupiedEntryRef<'a, 'b, K, Q, V, S, A>), |
4395 | |
4396 | /// A vacant entry. |
4397 | /// |
4398 | /// # Examples |
4399 | /// |
4400 | /// ``` |
4401 | /// use hashbrown::hash_map::{EntryRef, HashMap}; |
4402 | /// let mut map: HashMap<String, i32> = HashMap::new(); |
4403 | /// |
4404 | /// match map.entry_ref("a" ) { |
4405 | /// EntryRef::Occupied(_) => unreachable!(), |
4406 | /// EntryRef::Vacant(_) => { } |
4407 | /// } |
4408 | /// ``` |
4409 | Vacant(VacantEntryRef<'a, 'b, K, Q, V, S, A>), |
4410 | } |
4411 | |
4412 | impl<K: Borrow<Q>, Q: ?Sized + Debug, V: Debug, S, A: Allocator> Debug |
4413 | for EntryRef<'_, '_, K, Q, V, S, A> |
4414 | { |
4415 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4416 | match *self { |
4417 | EntryRef::Vacant(ref v: &VacantEntryRef<'_, '_, K, …, …, …, …>) => f.debug_tuple("EntryRef" ).field(v).finish(), |
4418 | EntryRef::Occupied(ref o: &OccupiedEntryRef<'_, '_, …, …, …, …, …>) => f.debug_tuple("EntryRef" ).field(o).finish(), |
4419 | } |
4420 | } |
4421 | } |
4422 | |
4423 | enum KeyOrRef<'a, K, Q: ?Sized> { |
4424 | Borrowed(&'a Q), |
4425 | Owned(K), |
4426 | } |
4427 | |
4428 | impl<'a, K, Q: ?Sized> KeyOrRef<'a, K, Q> { |
4429 | fn into_owned(self) -> K |
4430 | where |
4431 | K: From<&'a Q>, |
4432 | { |
4433 | match self { |
4434 | Self::Borrowed(borrowed: &Q) => borrowed.into(), |
4435 | Self::Owned(owned: K) => owned, |
4436 | } |
4437 | } |
4438 | } |
4439 | |
4440 | impl<'a, K: Borrow<Q>, Q: ?Sized> AsRef<Q> for KeyOrRef<'a, K, Q> { |
4441 | fn as_ref(&self) -> &Q { |
4442 | match self { |
4443 | Self::Borrowed(borrowed: &&Q) => borrowed, |
4444 | Self::Owned(owned: &K) => owned.borrow(), |
4445 | } |
4446 | } |
4447 | } |
4448 | |
4449 | /// A view into an occupied entry in a `HashMap`. |
4450 | /// It is part of the [`EntryRef`] enum. |
4451 | /// |
4452 | /// [`EntryRef`]: enum.EntryRef.html |
4453 | /// |
4454 | /// # Examples |
4455 | /// |
4456 | /// ``` |
4457 | /// use hashbrown::hash_map::{EntryRef, HashMap, OccupiedEntryRef}; |
4458 | /// |
4459 | /// let mut map = HashMap::new(); |
4460 | /// map.extend([("a" .to_owned(), 10), ("b" .into(), 20), ("c" .into(), 30)]); |
4461 | /// |
4462 | /// let key = String::from("a" ); |
4463 | /// let _entry_o: OccupiedEntryRef<_, _, _, _> = map.entry_ref(&key).insert(100); |
4464 | /// assert_eq!(map.len(), 3); |
4465 | /// |
4466 | /// // Existing key (insert and update) |
4467 | /// match map.entry_ref("a" ) { |
4468 | /// EntryRef::Vacant(_) => unreachable!(), |
4469 | /// EntryRef::Occupied(mut view) => { |
4470 | /// assert_eq!(view.get(), &100); |
4471 | /// let v = view.get_mut(); |
4472 | /// *v *= 10; |
4473 | /// assert_eq!(view.insert(1111), 1000); |
4474 | /// } |
4475 | /// } |
4476 | /// |
4477 | /// assert_eq!(map["a" ], 1111); |
4478 | /// assert_eq!(map.len(), 3); |
4479 | /// |
4480 | /// // Existing key (take) |
4481 | /// match map.entry_ref("c" ) { |
4482 | /// EntryRef::Vacant(_) => unreachable!(), |
4483 | /// EntryRef::Occupied(view) => { |
4484 | /// assert_eq!(view.remove_entry(), ("c" .to_owned(), 30)); |
4485 | /// } |
4486 | /// } |
4487 | /// assert_eq!(map.get("c" ), None); |
4488 | /// assert_eq!(map.len(), 2); |
4489 | /// ``` |
4490 | pub struct OccupiedEntryRef<'a, 'b, K, Q: ?Sized, V, S, A: Allocator = Global> { |
4491 | hash: u64, |
4492 | key: Option<KeyOrRef<'b, K, Q>>, |
4493 | elem: Bucket<(K, V)>, |
4494 | table: &'a mut HashMap<K, V, S, A>, |
4495 | } |
4496 | |
4497 | unsafe impl<'a, 'b, K, Q, V, S, A> Send for OccupiedEntryRef<'a, 'b, K, Q, V, S, A> |
4498 | where |
4499 | K: Send, |
4500 | Q: Sync + ?Sized, |
4501 | V: Send, |
4502 | S: Send, |
4503 | A: Send + Allocator, |
4504 | { |
4505 | } |
4506 | unsafe impl<'a, 'b, K, Q, V, S, A> Sync for OccupiedEntryRef<'a, 'b, K, Q, V, S, A> |
4507 | where |
4508 | K: Sync, |
4509 | Q: Sync + ?Sized, |
4510 | V: Sync, |
4511 | S: Sync, |
4512 | A: Sync + Allocator, |
4513 | { |
4514 | } |
4515 | |
4516 | impl<K: Borrow<Q>, Q: ?Sized + Debug, V: Debug, S, A: Allocator> Debug |
4517 | for OccupiedEntryRef<'_, '_, K, Q, V, S, A> |
4518 | { |
4519 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4520 | f.debug_struct("OccupiedEntryRef" ) |
4521 | .field("key" , &self.key().borrow()) |
4522 | .field("value" , &self.get()) |
4523 | .finish() |
4524 | } |
4525 | } |
4526 | |
4527 | /// A view into a vacant entry in a `HashMap`. |
4528 | /// It is part of the [`EntryRef`] enum. |
4529 | /// |
4530 | /// [`EntryRef`]: enum.EntryRef.html |
4531 | /// |
4532 | /// # Examples |
4533 | /// |
4534 | /// ``` |
4535 | /// use hashbrown::hash_map::{EntryRef, HashMap, VacantEntryRef}; |
4536 | /// |
4537 | /// let mut map = HashMap::<String, i32>::new(); |
4538 | /// |
4539 | /// let entry_v: VacantEntryRef<_, _, _, _> = match map.entry_ref("a" ) { |
4540 | /// EntryRef::Vacant(view) => view, |
4541 | /// EntryRef::Occupied(_) => unreachable!(), |
4542 | /// }; |
4543 | /// entry_v.insert(10); |
4544 | /// assert!(map["a" ] == 10 && map.len() == 1); |
4545 | /// |
4546 | /// // Nonexistent key (insert and update) |
4547 | /// match map.entry_ref("b" ) { |
4548 | /// EntryRef::Occupied(_) => unreachable!(), |
4549 | /// EntryRef::Vacant(view) => { |
4550 | /// let value = view.insert(2); |
4551 | /// assert_eq!(*value, 2); |
4552 | /// *value = 20; |
4553 | /// } |
4554 | /// } |
4555 | /// assert!(map["b" ] == 20 && map.len() == 2); |
4556 | /// ``` |
4557 | pub struct VacantEntryRef<'a, 'b, K, Q: ?Sized, V, S, A: Allocator = Global> { |
4558 | hash: u64, |
4559 | key: KeyOrRef<'b, K, Q>, |
4560 | table: &'a mut HashMap<K, V, S, A>, |
4561 | } |
4562 | |
4563 | impl<K: Borrow<Q>, Q: ?Sized + Debug, V, S, A: Allocator> Debug |
4564 | for VacantEntryRef<'_, '_, K, Q, V, S, A> |
4565 | { |
4566 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4567 | f.debug_tuple("VacantEntryRef" ).field(&self.key()).finish() |
4568 | } |
4569 | } |
4570 | |
4571 | /// The error returned by [`try_insert`](HashMap::try_insert) when the key already exists. |
4572 | /// |
4573 | /// Contains the occupied entry, and the value that was not inserted. |
4574 | /// |
4575 | /// # Examples |
4576 | /// |
4577 | /// ``` |
4578 | /// use hashbrown::hash_map::{HashMap, OccupiedError}; |
4579 | /// |
4580 | /// let mut map: HashMap<_, _> = [("a" , 10), ("b" , 20)].into(); |
4581 | /// |
4582 | /// // try_insert method returns mutable reference to the value if keys are vacant, |
4583 | /// // but if the map did have key present, nothing is updated, and the provided |
4584 | /// // value is returned inside `Err(_)` variant |
4585 | /// match map.try_insert("a" , 100) { |
4586 | /// Err(OccupiedError { mut entry, value }) => { |
4587 | /// assert_eq!(entry.key(), &"a" ); |
4588 | /// assert_eq!(value, 100); |
4589 | /// assert_eq!(entry.insert(100), 10) |
4590 | /// } |
4591 | /// _ => unreachable!(), |
4592 | /// } |
4593 | /// assert_eq!(map[&"a" ], 100); |
4594 | /// ``` |
4595 | pub struct OccupiedError<'a, K, V, S, A: Allocator = Global> { |
4596 | /// The entry in the map that was already occupied. |
4597 | pub entry: OccupiedEntry<'a, K, V, S, A>, |
4598 | /// The value which was not inserted, because the entry was already occupied. |
4599 | pub value: V, |
4600 | } |
4601 | |
4602 | impl<K: Debug, V: Debug, S, A: Allocator> Debug for OccupiedError<'_, K, V, S, A> { |
4603 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4604 | f.debug_struct("OccupiedError" ) |
4605 | .field("key" , self.entry.key()) |
4606 | .field("old_value" , self.entry.get()) |
4607 | .field("new_value" , &self.value) |
4608 | .finish() |
4609 | } |
4610 | } |
4611 | |
4612 | impl<'a, K: Debug, V: Debug, S, A: Allocator> fmt::Display for OccupiedError<'a, K, V, S, A> { |
4613 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4614 | write!( |
4615 | f, |
4616 | "failed to insert {:?}, key {:?} already exists with value {:?}" , |
4617 | self.value, |
4618 | self.entry.key(), |
4619 | self.entry.get(), |
4620 | ) |
4621 | } |
4622 | } |
4623 | |
4624 | impl<'a, K, V, S, A: Allocator> IntoIterator for &'a HashMap<K, V, S, A> { |
4625 | type Item = (&'a K, &'a V); |
4626 | type IntoIter = Iter<'a, K, V>; |
4627 | |
4628 | /// Creates an iterator over the entries of a `HashMap` in arbitrary order. |
4629 | /// The iterator element type is `(&'a K, &'a V)`. |
4630 | /// |
4631 | /// Return the same `Iter` struct as by the [`iter`] method on [`HashMap`]. |
4632 | /// |
4633 | /// [`iter`]: struct.HashMap.html#method.iter |
4634 | /// [`HashMap`]: struct.HashMap.html |
4635 | /// |
4636 | /// # Examples |
4637 | /// |
4638 | /// ``` |
4639 | /// use hashbrown::HashMap; |
4640 | /// let map_one: HashMap<_, _> = [(1, "a" ), (2, "b" ), (3, "c" )].into(); |
4641 | /// let mut map_two = HashMap::new(); |
4642 | /// |
4643 | /// for (key, value) in &map_one { |
4644 | /// println!("Key: {}, Value: {}" , key, value); |
4645 | /// map_two.insert_unique_unchecked(*key, *value); |
4646 | /// } |
4647 | /// |
4648 | /// assert_eq!(map_one, map_two); |
4649 | /// ``` |
4650 | #[cfg_attr (feature = "inline-more" , inline)] |
4651 | fn into_iter(self) -> Iter<'a, K, V> { |
4652 | self.iter() |
4653 | } |
4654 | } |
4655 | |
4656 | impl<'a, K, V, S, A: Allocator> IntoIterator for &'a mut HashMap<K, V, S, A> { |
4657 | type Item = (&'a K, &'a mut V); |
4658 | type IntoIter = IterMut<'a, K, V>; |
4659 | |
4660 | /// Creates an iterator over the entries of a `HashMap` in arbitrary order |
4661 | /// with mutable references to the values. The iterator element type is |
4662 | /// `(&'a K, &'a mut V)`. |
4663 | /// |
4664 | /// Return the same `IterMut` struct as by the [`iter_mut`] method on |
4665 | /// [`HashMap`]. |
4666 | /// |
4667 | /// [`iter_mut`]: struct.HashMap.html#method.iter_mut |
4668 | /// [`HashMap`]: struct.HashMap.html |
4669 | /// |
4670 | /// # Examples |
4671 | /// |
4672 | /// ``` |
4673 | /// use hashbrown::HashMap; |
4674 | /// let mut map: HashMap<_, _> = [("a" , 1), ("b" , 2), ("c" , 3)].into(); |
4675 | /// |
4676 | /// for (key, value) in &mut map { |
4677 | /// println!("Key: {}, Value: {}" , key, value); |
4678 | /// *value *= 2; |
4679 | /// } |
4680 | /// |
4681 | /// let mut vec = map.iter().collect::<Vec<_>>(); |
4682 | /// // The `Iter` iterator produces items in arbitrary order, so the |
4683 | /// // items must be sorted to test them against a sorted array. |
4684 | /// vec.sort_unstable(); |
4685 | /// assert_eq!(vec, [(&"a" , &2), (&"b" , &4), (&"c" , &6)]); |
4686 | /// ``` |
4687 | #[cfg_attr (feature = "inline-more" , inline)] |
4688 | fn into_iter(self) -> IterMut<'a, K, V> { |
4689 | self.iter_mut() |
4690 | } |
4691 | } |
4692 | |
4693 | impl<K, V, S, A: Allocator> IntoIterator for HashMap<K, V, S, A> { |
4694 | type Item = (K, V); |
4695 | type IntoIter = IntoIter<K, V, A>; |
4696 | |
4697 | /// Creates a consuming iterator, that is, one that moves each key-value |
4698 | /// pair out of the map in arbitrary order. The map cannot be used after |
4699 | /// calling this. |
4700 | /// |
4701 | /// # Examples |
4702 | /// |
4703 | /// ``` |
4704 | /// use hashbrown::HashMap; |
4705 | /// |
4706 | /// let map: HashMap<_, _> = [("a" , 1), ("b" , 2), ("c" , 3)].into(); |
4707 | /// |
4708 | /// // Not possible with .iter() |
4709 | /// let mut vec: Vec<(&str, i32)> = map.into_iter().collect(); |
4710 | /// // The `IntoIter` iterator produces items in arbitrary order, so |
4711 | /// // the items must be sorted to test them against a sorted array. |
4712 | /// vec.sort_unstable(); |
4713 | /// assert_eq!(vec, [("a" , 1), ("b" , 2), ("c" , 3)]); |
4714 | /// ``` |
4715 | #[cfg_attr (feature = "inline-more" , inline)] |
4716 | fn into_iter(self) -> IntoIter<K, V, A> { |
4717 | IntoIter { |
4718 | inner: self.table.into_iter(), |
4719 | } |
4720 | } |
4721 | } |
4722 | |
4723 | impl<'a, K, V> Iterator for Iter<'a, K, V> { |
4724 | type Item = (&'a K, &'a V); |
4725 | |
4726 | #[cfg_attr (feature = "inline-more" , inline)] |
4727 | fn next(&mut self) -> Option<(&'a K, &'a V)> { |
4728 | // Avoid `Option::map` because it bloats LLVM IR. |
4729 | match self.inner.next() { |
4730 | Some(x) => unsafe { |
4731 | let r = x.as_ref(); |
4732 | Some((&r.0, &r.1)) |
4733 | }, |
4734 | None => None, |
4735 | } |
4736 | } |
4737 | #[cfg_attr (feature = "inline-more" , inline)] |
4738 | fn size_hint(&self) -> (usize, Option<usize>) { |
4739 | self.inner.size_hint() |
4740 | } |
4741 | #[cfg_attr (feature = "inline-more" , inline)] |
4742 | fn fold<B, F>(self, init: B, mut f: F) -> B |
4743 | where |
4744 | Self: Sized, |
4745 | F: FnMut(B, Self::Item) -> B, |
4746 | { |
4747 | self.inner.fold(init, |acc, x| unsafe { |
4748 | let (k, v) = x.as_ref(); |
4749 | f(acc, (k, v)) |
4750 | }) |
4751 | } |
4752 | } |
4753 | impl<K, V> ExactSizeIterator for Iter<'_, K, V> { |
4754 | #[cfg_attr (feature = "inline-more" , inline)] |
4755 | fn len(&self) -> usize { |
4756 | self.inner.len() |
4757 | } |
4758 | } |
4759 | |
4760 | impl<K, V> FusedIterator for Iter<'_, K, V> {} |
4761 | |
4762 | impl<'a, K, V> Iterator for IterMut<'a, K, V> { |
4763 | type Item = (&'a K, &'a mut V); |
4764 | |
4765 | #[cfg_attr (feature = "inline-more" , inline)] |
4766 | fn next(&mut self) -> Option<(&'a K, &'a mut V)> { |
4767 | // Avoid `Option::map` because it bloats LLVM IR. |
4768 | match self.inner.next() { |
4769 | Some(x) => unsafe { |
4770 | let r = x.as_mut(); |
4771 | Some((&r.0, &mut r.1)) |
4772 | }, |
4773 | None => None, |
4774 | } |
4775 | } |
4776 | #[cfg_attr (feature = "inline-more" , inline)] |
4777 | fn size_hint(&self) -> (usize, Option<usize>) { |
4778 | self.inner.size_hint() |
4779 | } |
4780 | #[cfg_attr (feature = "inline-more" , inline)] |
4781 | fn fold<B, F>(self, init: B, mut f: F) -> B |
4782 | where |
4783 | Self: Sized, |
4784 | F: FnMut(B, Self::Item) -> B, |
4785 | { |
4786 | self.inner.fold(init, |acc, x| unsafe { |
4787 | let (k, v) = x.as_mut(); |
4788 | f(acc, (k, v)) |
4789 | }) |
4790 | } |
4791 | } |
4792 | impl<K, V> ExactSizeIterator for IterMut<'_, K, V> { |
4793 | #[cfg_attr (feature = "inline-more" , inline)] |
4794 | fn len(&self) -> usize { |
4795 | self.inner.len() |
4796 | } |
4797 | } |
4798 | impl<K, V> FusedIterator for IterMut<'_, K, V> {} |
4799 | |
4800 | impl<K, V> fmt::Debug for IterMut<'_, K, V> |
4801 | where |
4802 | K: fmt::Debug, |
4803 | V: fmt::Debug, |
4804 | { |
4805 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4806 | f.debug_list().entries(self.iter()).finish() |
4807 | } |
4808 | } |
4809 | |
4810 | impl<K, V, A: Allocator> Iterator for IntoIter<K, V, A> { |
4811 | type Item = (K, V); |
4812 | |
4813 | #[cfg_attr (feature = "inline-more" , inline)] |
4814 | fn next(&mut self) -> Option<(K, V)> { |
4815 | self.inner.next() |
4816 | } |
4817 | #[cfg_attr (feature = "inline-more" , inline)] |
4818 | fn size_hint(&self) -> (usize, Option<usize>) { |
4819 | self.inner.size_hint() |
4820 | } |
4821 | #[cfg_attr (feature = "inline-more" , inline)] |
4822 | fn fold<B, F>(self, init: B, f: F) -> B |
4823 | where |
4824 | Self: Sized, |
4825 | F: FnMut(B, Self::Item) -> B, |
4826 | { |
4827 | self.inner.fold(init, f) |
4828 | } |
4829 | } |
4830 | impl<K, V, A: Allocator> ExactSizeIterator for IntoIter<K, V, A> { |
4831 | #[cfg_attr (feature = "inline-more" , inline)] |
4832 | fn len(&self) -> usize { |
4833 | self.inner.len() |
4834 | } |
4835 | } |
4836 | impl<K, V, A: Allocator> FusedIterator for IntoIter<K, V, A> {} |
4837 | |
4838 | impl<K: Debug, V: Debug, A: Allocator> fmt::Debug for IntoIter<K, V, A> { |
4839 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4840 | f.debug_list().entries(self.iter()).finish() |
4841 | } |
4842 | } |
4843 | |
4844 | impl<'a, K, V> Iterator for Keys<'a, K, V> { |
4845 | type Item = &'a K; |
4846 | |
4847 | #[cfg_attr (feature = "inline-more" , inline)] |
4848 | fn next(&mut self) -> Option<&'a K> { |
4849 | // Avoid `Option::map` because it bloats LLVM IR. |
4850 | match self.inner.next() { |
4851 | Some((k, _)) => Some(k), |
4852 | None => None, |
4853 | } |
4854 | } |
4855 | #[cfg_attr (feature = "inline-more" , inline)] |
4856 | fn size_hint(&self) -> (usize, Option<usize>) { |
4857 | self.inner.size_hint() |
4858 | } |
4859 | #[cfg_attr (feature = "inline-more" , inline)] |
4860 | fn fold<B, F>(self, init: B, mut f: F) -> B |
4861 | where |
4862 | Self: Sized, |
4863 | F: FnMut(B, Self::Item) -> B, |
4864 | { |
4865 | self.inner.fold(init, |acc, (k, _)| f(acc, k)) |
4866 | } |
4867 | } |
4868 | impl<K, V> ExactSizeIterator for Keys<'_, K, V> { |
4869 | #[cfg_attr (feature = "inline-more" , inline)] |
4870 | fn len(&self) -> usize { |
4871 | self.inner.len() |
4872 | } |
4873 | } |
4874 | impl<K, V> FusedIterator for Keys<'_, K, V> {} |
4875 | |
4876 | impl<'a, K, V> Iterator for Values<'a, K, V> { |
4877 | type Item = &'a V; |
4878 | |
4879 | #[cfg_attr (feature = "inline-more" , inline)] |
4880 | fn next(&mut self) -> Option<&'a V> { |
4881 | // Avoid `Option::map` because it bloats LLVM IR. |
4882 | match self.inner.next() { |
4883 | Some((_, v)) => Some(v), |
4884 | None => None, |
4885 | } |
4886 | } |
4887 | #[cfg_attr (feature = "inline-more" , inline)] |
4888 | fn size_hint(&self) -> (usize, Option<usize>) { |
4889 | self.inner.size_hint() |
4890 | } |
4891 | #[cfg_attr (feature = "inline-more" , inline)] |
4892 | fn fold<B, F>(self, init: B, mut f: F) -> B |
4893 | where |
4894 | Self: Sized, |
4895 | F: FnMut(B, Self::Item) -> B, |
4896 | { |
4897 | self.inner.fold(init, |acc, (_, v)| f(acc, v)) |
4898 | } |
4899 | } |
4900 | impl<K, V> ExactSizeIterator for Values<'_, K, V> { |
4901 | #[cfg_attr (feature = "inline-more" , inline)] |
4902 | fn len(&self) -> usize { |
4903 | self.inner.len() |
4904 | } |
4905 | } |
4906 | impl<K, V> FusedIterator for Values<'_, K, V> {} |
4907 | |
4908 | impl<'a, K, V> Iterator for ValuesMut<'a, K, V> { |
4909 | type Item = &'a mut V; |
4910 | |
4911 | #[cfg_attr (feature = "inline-more" , inline)] |
4912 | fn next(&mut self) -> Option<&'a mut V> { |
4913 | // Avoid `Option::map` because it bloats LLVM IR. |
4914 | match self.inner.next() { |
4915 | Some((_, v)) => Some(v), |
4916 | None => None, |
4917 | } |
4918 | } |
4919 | #[cfg_attr (feature = "inline-more" , inline)] |
4920 | fn size_hint(&self) -> (usize, Option<usize>) { |
4921 | self.inner.size_hint() |
4922 | } |
4923 | #[cfg_attr (feature = "inline-more" , inline)] |
4924 | fn fold<B, F>(self, init: B, mut f: F) -> B |
4925 | where |
4926 | Self: Sized, |
4927 | F: FnMut(B, Self::Item) -> B, |
4928 | { |
4929 | self.inner.fold(init, |acc, (_, v)| f(acc, v)) |
4930 | } |
4931 | } |
4932 | impl<K, V> ExactSizeIterator for ValuesMut<'_, K, V> { |
4933 | #[cfg_attr (feature = "inline-more" , inline)] |
4934 | fn len(&self) -> usize { |
4935 | self.inner.len() |
4936 | } |
4937 | } |
4938 | impl<K, V> FusedIterator for ValuesMut<'_, K, V> {} |
4939 | |
4940 | impl<K, V: Debug> fmt::Debug for ValuesMut<'_, K, V> { |
4941 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4942 | f.debug_list() |
4943 | .entries(self.inner.iter().map(|(_, val)| val)) |
4944 | .finish() |
4945 | } |
4946 | } |
4947 | |
4948 | impl<'a, K, V, A: Allocator> Iterator for Drain<'a, K, V, A> { |
4949 | type Item = (K, V); |
4950 | |
4951 | #[cfg_attr (feature = "inline-more" , inline)] |
4952 | fn next(&mut self) -> Option<(K, V)> { |
4953 | self.inner.next() |
4954 | } |
4955 | #[cfg_attr (feature = "inline-more" , inline)] |
4956 | fn size_hint(&self) -> (usize, Option<usize>) { |
4957 | self.inner.size_hint() |
4958 | } |
4959 | #[cfg_attr (feature = "inline-more" , inline)] |
4960 | fn fold<B, F>(self, init: B, f: F) -> B |
4961 | where |
4962 | Self: Sized, |
4963 | F: FnMut(B, Self::Item) -> B, |
4964 | { |
4965 | self.inner.fold(init, f) |
4966 | } |
4967 | } |
4968 | impl<K, V, A: Allocator> ExactSizeIterator for Drain<'_, K, V, A> { |
4969 | #[cfg_attr (feature = "inline-more" , inline)] |
4970 | fn len(&self) -> usize { |
4971 | self.inner.len() |
4972 | } |
4973 | } |
4974 | impl<K, V, A: Allocator> FusedIterator for Drain<'_, K, V, A> {} |
4975 | |
4976 | impl<K, V, A> fmt::Debug for Drain<'_, K, V, A> |
4977 | where |
4978 | K: fmt::Debug, |
4979 | V: fmt::Debug, |
4980 | A: Allocator, |
4981 | { |
4982 | fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
4983 | f.debug_list().entries(self.iter()).finish() |
4984 | } |
4985 | } |
4986 | |
4987 | impl<'a, K, V, S, A: Allocator> Entry<'a, K, V, S, A> { |
4988 | /// Sets the value of the entry, and returns an OccupiedEntry. |
4989 | /// |
4990 | /// # Examples |
4991 | /// |
4992 | /// ``` |
4993 | /// use hashbrown::HashMap; |
4994 | /// |
4995 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
4996 | /// let entry = map.entry("horseyland" ).insert(37); |
4997 | /// |
4998 | /// assert_eq!(entry.key(), &"horseyland" ); |
4999 | /// ``` |
5000 | #[cfg_attr (feature = "inline-more" , inline)] |
5001 | pub fn insert(self, value: V) -> OccupiedEntry<'a, K, V, S, A> |
5002 | where |
5003 | K: Hash, |
5004 | S: BuildHasher, |
5005 | { |
5006 | match self { |
5007 | Entry::Occupied(mut entry) => { |
5008 | entry.insert(value); |
5009 | entry |
5010 | } |
5011 | Entry::Vacant(entry) => entry.insert_entry(value), |
5012 | } |
5013 | } |
5014 | |
5015 | /// Ensures a value is in the entry by inserting the default if empty, and returns |
5016 | /// a mutable reference to the value in the entry. |
5017 | /// |
5018 | /// # Examples |
5019 | /// |
5020 | /// ``` |
5021 | /// use hashbrown::HashMap; |
5022 | /// |
5023 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5024 | /// |
5025 | /// // nonexistent key |
5026 | /// map.entry("poneyland" ).or_insert(3); |
5027 | /// assert_eq!(map["poneyland" ], 3); |
5028 | /// |
5029 | /// // existing key |
5030 | /// *map.entry("poneyland" ).or_insert(10) *= 2; |
5031 | /// assert_eq!(map["poneyland" ], 6); |
5032 | /// ``` |
5033 | #[cfg_attr (feature = "inline-more" , inline)] |
5034 | pub fn or_insert(self, default: V) -> &'a mut V |
5035 | where |
5036 | K: Hash, |
5037 | S: BuildHasher, |
5038 | { |
5039 | match self { |
5040 | Entry::Occupied(entry) => entry.into_mut(), |
5041 | Entry::Vacant(entry) => entry.insert(default), |
5042 | } |
5043 | } |
5044 | |
5045 | /// Ensures a value is in the entry by inserting the result of the default function if empty, |
5046 | /// and returns a mutable reference to the value in the entry. |
5047 | /// |
5048 | /// # Examples |
5049 | /// |
5050 | /// ``` |
5051 | /// use hashbrown::HashMap; |
5052 | /// |
5053 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5054 | /// |
5055 | /// // nonexistent key |
5056 | /// map.entry("poneyland" ).or_insert_with(|| 3); |
5057 | /// assert_eq!(map["poneyland" ], 3); |
5058 | /// |
5059 | /// // existing key |
5060 | /// *map.entry("poneyland" ).or_insert_with(|| 10) *= 2; |
5061 | /// assert_eq!(map["poneyland" ], 6); |
5062 | /// ``` |
5063 | #[cfg_attr (feature = "inline-more" , inline)] |
5064 | pub fn or_insert_with<F: FnOnce() -> V>(self, default: F) -> &'a mut V |
5065 | where |
5066 | K: Hash, |
5067 | S: BuildHasher, |
5068 | { |
5069 | match self { |
5070 | Entry::Occupied(entry) => entry.into_mut(), |
5071 | Entry::Vacant(entry) => entry.insert(default()), |
5072 | } |
5073 | } |
5074 | |
5075 | /// Ensures a value is in the entry by inserting, if empty, the result of the default function. |
5076 | /// This method allows for generating key-derived values for insertion by providing the default |
5077 | /// function a reference to the key that was moved during the `.entry(key)` method call. |
5078 | /// |
5079 | /// The reference to the moved key is provided so that cloning or copying the key is |
5080 | /// unnecessary, unlike with `.or_insert_with(|| ... )`. |
5081 | /// |
5082 | /// # Examples |
5083 | /// |
5084 | /// ``` |
5085 | /// use hashbrown::HashMap; |
5086 | /// |
5087 | /// let mut map: HashMap<&str, usize> = HashMap::new(); |
5088 | /// |
5089 | /// // nonexistent key |
5090 | /// map.entry("poneyland" ).or_insert_with_key(|key| key.chars().count()); |
5091 | /// assert_eq!(map["poneyland" ], 9); |
5092 | /// |
5093 | /// // existing key |
5094 | /// *map.entry("poneyland" ).or_insert_with_key(|key| key.chars().count() * 10) *= 2; |
5095 | /// assert_eq!(map["poneyland" ], 18); |
5096 | /// ``` |
5097 | #[cfg_attr (feature = "inline-more" , inline)] |
5098 | pub fn or_insert_with_key<F: FnOnce(&K) -> V>(self, default: F) -> &'a mut V |
5099 | where |
5100 | K: Hash, |
5101 | S: BuildHasher, |
5102 | { |
5103 | match self { |
5104 | Entry::Occupied(entry) => entry.into_mut(), |
5105 | Entry::Vacant(entry) => { |
5106 | let value = default(entry.key()); |
5107 | entry.insert(value) |
5108 | } |
5109 | } |
5110 | } |
5111 | |
5112 | /// Returns a reference to this entry's key. |
5113 | /// |
5114 | /// # Examples |
5115 | /// |
5116 | /// ``` |
5117 | /// use hashbrown::HashMap; |
5118 | /// |
5119 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5120 | /// map.entry("poneyland" ).or_insert(3); |
5121 | /// // existing key |
5122 | /// assert_eq!(map.entry("poneyland" ).key(), &"poneyland" ); |
5123 | /// // nonexistent key |
5124 | /// assert_eq!(map.entry("horseland" ).key(), &"horseland" ); |
5125 | /// ``` |
5126 | #[cfg_attr (feature = "inline-more" , inline)] |
5127 | pub fn key(&self) -> &K { |
5128 | match *self { |
5129 | Entry::Occupied(ref entry) => entry.key(), |
5130 | Entry::Vacant(ref entry) => entry.key(), |
5131 | } |
5132 | } |
5133 | |
5134 | /// Provides in-place mutable access to an occupied entry before any |
5135 | /// potential inserts into the map. |
5136 | /// |
5137 | /// # Examples |
5138 | /// |
5139 | /// ``` |
5140 | /// use hashbrown::HashMap; |
5141 | /// |
5142 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5143 | /// |
5144 | /// map.entry("poneyland" ) |
5145 | /// .and_modify(|e| { *e += 1 }) |
5146 | /// .or_insert(42); |
5147 | /// assert_eq!(map["poneyland" ], 42); |
5148 | /// |
5149 | /// map.entry("poneyland" ) |
5150 | /// .and_modify(|e| { *e += 1 }) |
5151 | /// .or_insert(42); |
5152 | /// assert_eq!(map["poneyland" ], 43); |
5153 | /// ``` |
5154 | #[cfg_attr (feature = "inline-more" , inline)] |
5155 | pub fn and_modify<F>(self, f: F) -> Self |
5156 | where |
5157 | F: FnOnce(&mut V), |
5158 | { |
5159 | match self { |
5160 | Entry::Occupied(mut entry) => { |
5161 | f(entry.get_mut()); |
5162 | Entry::Occupied(entry) |
5163 | } |
5164 | Entry::Vacant(entry) => Entry::Vacant(entry), |
5165 | } |
5166 | } |
5167 | |
5168 | /// Provides shared access to the key and owned access to the value of |
5169 | /// an occupied entry and allows to replace or remove it based on the |
5170 | /// value of the returned option. |
5171 | /// |
5172 | /// # Examples |
5173 | /// |
5174 | /// ``` |
5175 | /// use hashbrown::HashMap; |
5176 | /// use hashbrown::hash_map::Entry; |
5177 | /// |
5178 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5179 | /// |
5180 | /// let entry = map |
5181 | /// .entry("poneyland" ) |
5182 | /// .and_replace_entry_with(|_k, _v| panic!()); |
5183 | /// |
5184 | /// match entry { |
5185 | /// Entry::Vacant(e) => { |
5186 | /// assert_eq!(e.key(), &"poneyland" ); |
5187 | /// } |
5188 | /// Entry::Occupied(_) => panic!(), |
5189 | /// } |
5190 | /// |
5191 | /// map.insert("poneyland" , 42); |
5192 | /// |
5193 | /// let entry = map |
5194 | /// .entry("poneyland" ) |
5195 | /// .and_replace_entry_with(|k, v| { |
5196 | /// assert_eq!(k, &"poneyland" ); |
5197 | /// assert_eq!(v, 42); |
5198 | /// Some(v + 1) |
5199 | /// }); |
5200 | /// |
5201 | /// match entry { |
5202 | /// Entry::Occupied(e) => { |
5203 | /// assert_eq!(e.key(), &"poneyland" ); |
5204 | /// assert_eq!(e.get(), &43); |
5205 | /// } |
5206 | /// Entry::Vacant(_) => panic!(), |
5207 | /// } |
5208 | /// |
5209 | /// assert_eq!(map["poneyland" ], 43); |
5210 | /// |
5211 | /// let entry = map |
5212 | /// .entry("poneyland" ) |
5213 | /// .and_replace_entry_with(|_k, _v| None); |
5214 | /// |
5215 | /// match entry { |
5216 | /// Entry::Vacant(e) => assert_eq!(e.key(), &"poneyland" ), |
5217 | /// Entry::Occupied(_) => panic!(), |
5218 | /// } |
5219 | /// |
5220 | /// assert!(!map.contains_key("poneyland" )); |
5221 | /// ``` |
5222 | #[cfg_attr (feature = "inline-more" , inline)] |
5223 | pub fn and_replace_entry_with<F>(self, f: F) -> Self |
5224 | where |
5225 | F: FnOnce(&K, V) -> Option<V>, |
5226 | { |
5227 | match self { |
5228 | Entry::Occupied(entry) => entry.replace_entry_with(f), |
5229 | Entry::Vacant(_) => self, |
5230 | } |
5231 | } |
5232 | } |
5233 | |
5234 | impl<'a, K, V: Default, S, A: Allocator> Entry<'a, K, V, S, A> { |
5235 | /// Ensures a value is in the entry by inserting the default value if empty, |
5236 | /// and returns a mutable reference to the value in the entry. |
5237 | /// |
5238 | /// # Examples |
5239 | /// |
5240 | /// ``` |
5241 | /// use hashbrown::HashMap; |
5242 | /// |
5243 | /// let mut map: HashMap<&str, Option<u32>> = HashMap::new(); |
5244 | /// |
5245 | /// // nonexistent key |
5246 | /// map.entry("poneyland" ).or_default(); |
5247 | /// assert_eq!(map["poneyland" ], None); |
5248 | /// |
5249 | /// map.insert("horseland" , Some(3)); |
5250 | /// |
5251 | /// // existing key |
5252 | /// assert_eq!(map.entry("horseland" ).or_default(), &mut Some(3)); |
5253 | /// ``` |
5254 | #[cfg_attr (feature = "inline-more" , inline)] |
5255 | pub fn or_default(self) -> &'a mut V |
5256 | where |
5257 | K: Hash, |
5258 | S: BuildHasher, |
5259 | { |
5260 | match self { |
5261 | Entry::Occupied(entry) => entry.into_mut(), |
5262 | Entry::Vacant(entry) => entry.insert(Default::default()), |
5263 | } |
5264 | } |
5265 | } |
5266 | |
5267 | impl<'a, K, V, S, A: Allocator> OccupiedEntry<'a, K, V, S, A> { |
5268 | /// Gets a reference to the key in the entry. |
5269 | /// |
5270 | /// # Examples |
5271 | /// |
5272 | /// ``` |
5273 | /// use hashbrown::hash_map::{Entry, HashMap}; |
5274 | /// |
5275 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5276 | /// map.entry("poneyland" ).or_insert(12); |
5277 | /// |
5278 | /// match map.entry("poneyland" ) { |
5279 | /// Entry::Vacant(_) => panic!(), |
5280 | /// Entry::Occupied(entry) => assert_eq!(entry.key(), &"poneyland" ), |
5281 | /// } |
5282 | /// ``` |
5283 | #[cfg_attr (feature = "inline-more" , inline)] |
5284 | pub fn key(&self) -> &K { |
5285 | unsafe { &self.elem.as_ref().0 } |
5286 | } |
5287 | |
5288 | /// Take the ownership of the key and value from the map. |
5289 | /// Keeps the allocated memory for reuse. |
5290 | /// |
5291 | /// # Examples |
5292 | /// |
5293 | /// ``` |
5294 | /// use hashbrown::HashMap; |
5295 | /// use hashbrown::hash_map::Entry; |
5296 | /// |
5297 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5298 | /// // The map is empty |
5299 | /// assert!(map.is_empty() && map.capacity() == 0); |
5300 | /// |
5301 | /// map.entry("poneyland" ).or_insert(12); |
5302 | /// |
5303 | /// if let Entry::Occupied(o) = map.entry("poneyland" ) { |
5304 | /// // We delete the entry from the map. |
5305 | /// assert_eq!(o.remove_entry(), ("poneyland" , 12)); |
5306 | /// } |
5307 | /// |
5308 | /// assert_eq!(map.contains_key("poneyland" ), false); |
5309 | /// // Now map hold none elements |
5310 | /// assert!(map.is_empty()); |
5311 | /// ``` |
5312 | #[cfg_attr (feature = "inline-more" , inline)] |
5313 | pub fn remove_entry(self) -> (K, V) { |
5314 | unsafe { self.table.table.remove(self.elem).0 } |
5315 | } |
5316 | |
5317 | /// Gets a reference to the value in the entry. |
5318 | /// |
5319 | /// # Examples |
5320 | /// |
5321 | /// ``` |
5322 | /// use hashbrown::HashMap; |
5323 | /// use hashbrown::hash_map::Entry; |
5324 | /// |
5325 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5326 | /// map.entry("poneyland" ).or_insert(12); |
5327 | /// |
5328 | /// match map.entry("poneyland" ) { |
5329 | /// Entry::Vacant(_) => panic!(), |
5330 | /// Entry::Occupied(entry) => assert_eq!(entry.get(), &12), |
5331 | /// } |
5332 | /// ``` |
5333 | #[cfg_attr (feature = "inline-more" , inline)] |
5334 | pub fn get(&self) -> &V { |
5335 | unsafe { &self.elem.as_ref().1 } |
5336 | } |
5337 | |
5338 | /// Gets a mutable reference to the value in the entry. |
5339 | /// |
5340 | /// If you need a reference to the `OccupiedEntry` which may outlive the |
5341 | /// destruction of the `Entry` value, see [`into_mut`]. |
5342 | /// |
5343 | /// [`into_mut`]: #method.into_mut |
5344 | /// |
5345 | /// # Examples |
5346 | /// |
5347 | /// ``` |
5348 | /// use hashbrown::HashMap; |
5349 | /// use hashbrown::hash_map::Entry; |
5350 | /// |
5351 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5352 | /// map.entry("poneyland" ).or_insert(12); |
5353 | /// |
5354 | /// assert_eq!(map["poneyland" ], 12); |
5355 | /// if let Entry::Occupied(mut o) = map.entry("poneyland" ) { |
5356 | /// *o.get_mut() += 10; |
5357 | /// assert_eq!(*o.get(), 22); |
5358 | /// |
5359 | /// // We can use the same Entry multiple times. |
5360 | /// *o.get_mut() += 2; |
5361 | /// } |
5362 | /// |
5363 | /// assert_eq!(map["poneyland" ], 24); |
5364 | /// ``` |
5365 | #[cfg_attr (feature = "inline-more" , inline)] |
5366 | pub fn get_mut(&mut self) -> &mut V { |
5367 | unsafe { &mut self.elem.as_mut().1 } |
5368 | } |
5369 | |
5370 | /// Converts the OccupiedEntry into a mutable reference to the value in the entry |
5371 | /// with a lifetime bound to the map itself. |
5372 | /// |
5373 | /// If you need multiple references to the `OccupiedEntry`, see [`get_mut`]. |
5374 | /// |
5375 | /// [`get_mut`]: #method.get_mut |
5376 | /// |
5377 | /// # Examples |
5378 | /// |
5379 | /// ``` |
5380 | /// use hashbrown::hash_map::{Entry, HashMap}; |
5381 | /// |
5382 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5383 | /// map.entry("poneyland" ).or_insert(12); |
5384 | /// |
5385 | /// assert_eq!(map["poneyland" ], 12); |
5386 | /// |
5387 | /// let value: &mut u32; |
5388 | /// match map.entry("poneyland" ) { |
5389 | /// Entry::Occupied(entry) => value = entry.into_mut(), |
5390 | /// Entry::Vacant(_) => panic!(), |
5391 | /// } |
5392 | /// *value += 10; |
5393 | /// |
5394 | /// assert_eq!(map["poneyland" ], 22); |
5395 | /// ``` |
5396 | #[cfg_attr (feature = "inline-more" , inline)] |
5397 | pub fn into_mut(self) -> &'a mut V { |
5398 | unsafe { &mut self.elem.as_mut().1 } |
5399 | } |
5400 | |
5401 | /// Sets the value of the entry, and returns the entry's old value. |
5402 | /// |
5403 | /// # Examples |
5404 | /// |
5405 | /// ``` |
5406 | /// use hashbrown::HashMap; |
5407 | /// use hashbrown::hash_map::Entry; |
5408 | /// |
5409 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5410 | /// map.entry("poneyland" ).or_insert(12); |
5411 | /// |
5412 | /// if let Entry::Occupied(mut o) = map.entry("poneyland" ) { |
5413 | /// assert_eq!(o.insert(15), 12); |
5414 | /// } |
5415 | /// |
5416 | /// assert_eq!(map["poneyland" ], 15); |
5417 | /// ``` |
5418 | #[cfg_attr (feature = "inline-more" , inline)] |
5419 | pub fn insert(&mut self, value: V) -> V { |
5420 | mem::replace(self.get_mut(), value) |
5421 | } |
5422 | |
5423 | /// Takes the value out of the entry, and returns it. |
5424 | /// Keeps the allocated memory for reuse. |
5425 | /// |
5426 | /// # Examples |
5427 | /// |
5428 | /// ``` |
5429 | /// use hashbrown::HashMap; |
5430 | /// use hashbrown::hash_map::Entry; |
5431 | /// |
5432 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5433 | /// // The map is empty |
5434 | /// assert!(map.is_empty() && map.capacity() == 0); |
5435 | /// |
5436 | /// map.entry("poneyland" ).or_insert(12); |
5437 | /// |
5438 | /// if let Entry::Occupied(o) = map.entry("poneyland" ) { |
5439 | /// assert_eq!(o.remove(), 12); |
5440 | /// } |
5441 | /// |
5442 | /// assert_eq!(map.contains_key("poneyland" ), false); |
5443 | /// // Now map hold none elements |
5444 | /// assert!(map.is_empty()); |
5445 | /// ``` |
5446 | #[cfg_attr (feature = "inline-more" , inline)] |
5447 | pub fn remove(self) -> V { |
5448 | self.remove_entry().1 |
5449 | } |
5450 | |
5451 | /// Replaces the entry, returning the old key and value. The new key in the hash map will be |
5452 | /// the key used to create this entry. |
5453 | /// |
5454 | /// # Panics |
5455 | /// |
5456 | /// Will panic if this OccupiedEntry was created through [`Entry::insert`]. |
5457 | /// |
5458 | /// # Examples |
5459 | /// |
5460 | /// ``` |
5461 | /// use hashbrown::hash_map::{Entry, HashMap}; |
5462 | /// use std::rc::Rc; |
5463 | /// |
5464 | /// let mut map: HashMap<Rc<String>, u32> = HashMap::new(); |
5465 | /// let key_one = Rc::new("Stringthing" .to_string()); |
5466 | /// let key_two = Rc::new("Stringthing" .to_string()); |
5467 | /// |
5468 | /// map.insert(key_one.clone(), 15); |
5469 | /// assert!(Rc::strong_count(&key_one) == 2 && Rc::strong_count(&key_two) == 1); |
5470 | /// |
5471 | /// match map.entry(key_two.clone()) { |
5472 | /// Entry::Occupied(entry) => { |
5473 | /// let (old_key, old_value): (Rc<String>, u32) = entry.replace_entry(16); |
5474 | /// assert!(Rc::ptr_eq(&key_one, &old_key) && old_value == 15); |
5475 | /// } |
5476 | /// Entry::Vacant(_) => panic!(), |
5477 | /// } |
5478 | /// |
5479 | /// assert!(Rc::strong_count(&key_one) == 1 && Rc::strong_count(&key_two) == 2); |
5480 | /// assert_eq!(map[&"Stringthing" .to_owned()], 16); |
5481 | /// ``` |
5482 | #[cfg_attr (feature = "inline-more" , inline)] |
5483 | pub fn replace_entry(self, value: V) -> (K, V) { |
5484 | let entry = unsafe { self.elem.as_mut() }; |
5485 | |
5486 | let old_key = mem::replace(&mut entry.0, self.key.unwrap()); |
5487 | let old_value = mem::replace(&mut entry.1, value); |
5488 | |
5489 | (old_key, old_value) |
5490 | } |
5491 | |
5492 | /// Replaces the key in the hash map with the key used to create this entry. |
5493 | /// |
5494 | /// # Panics |
5495 | /// |
5496 | /// Will panic if this OccupiedEntry was created through [`Entry::insert`]. |
5497 | /// |
5498 | /// # Examples |
5499 | /// |
5500 | /// ``` |
5501 | /// use hashbrown::hash_map::{Entry, HashMap}; |
5502 | /// use std::rc::Rc; |
5503 | /// |
5504 | /// let mut map: HashMap<Rc<String>, usize> = HashMap::with_capacity(6); |
5505 | /// let mut keys_one: Vec<Rc<String>> = Vec::with_capacity(6); |
5506 | /// let mut keys_two: Vec<Rc<String>> = Vec::with_capacity(6); |
5507 | /// |
5508 | /// for (value, key) in ["a" , "b" , "c" , "d" , "e" , "f" ].into_iter().enumerate() { |
5509 | /// let rc_key = Rc::new(key.to_owned()); |
5510 | /// keys_one.push(rc_key.clone()); |
5511 | /// map.insert(rc_key.clone(), value); |
5512 | /// keys_two.push(Rc::new(key.to_owned())); |
5513 | /// } |
5514 | /// |
5515 | /// assert!( |
5516 | /// keys_one.iter().all(|key| Rc::strong_count(key) == 2) |
5517 | /// && keys_two.iter().all(|key| Rc::strong_count(key) == 1) |
5518 | /// ); |
5519 | /// |
5520 | /// reclaim_memory(&mut map, &keys_two); |
5521 | /// |
5522 | /// assert!( |
5523 | /// keys_one.iter().all(|key| Rc::strong_count(key) == 1) |
5524 | /// && keys_two.iter().all(|key| Rc::strong_count(key) == 2) |
5525 | /// ); |
5526 | /// |
5527 | /// fn reclaim_memory(map: &mut HashMap<Rc<String>, usize>, keys: &[Rc<String>]) { |
5528 | /// for key in keys { |
5529 | /// if let Entry::Occupied(entry) = map.entry(key.clone()) { |
5530 | /// // Replaces the entry's key with our version of it in `keys`. |
5531 | /// entry.replace_key(); |
5532 | /// } |
5533 | /// } |
5534 | /// } |
5535 | /// ``` |
5536 | #[cfg_attr (feature = "inline-more" , inline)] |
5537 | pub fn replace_key(self) -> K { |
5538 | let entry = unsafe { self.elem.as_mut() }; |
5539 | mem::replace(&mut entry.0, self.key.unwrap()) |
5540 | } |
5541 | |
5542 | /// Provides shared access to the key and owned access to the value of |
5543 | /// the entry and allows to replace or remove it based on the |
5544 | /// value of the returned option. |
5545 | /// |
5546 | /// # Examples |
5547 | /// |
5548 | /// ``` |
5549 | /// use hashbrown::HashMap; |
5550 | /// use hashbrown::hash_map::Entry; |
5551 | /// |
5552 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5553 | /// map.insert("poneyland" , 42); |
5554 | /// |
5555 | /// let entry = match map.entry("poneyland" ) { |
5556 | /// Entry::Occupied(e) => { |
5557 | /// e.replace_entry_with(|k, v| { |
5558 | /// assert_eq!(k, &"poneyland" ); |
5559 | /// assert_eq!(v, 42); |
5560 | /// Some(v + 1) |
5561 | /// }) |
5562 | /// } |
5563 | /// Entry::Vacant(_) => panic!(), |
5564 | /// }; |
5565 | /// |
5566 | /// match entry { |
5567 | /// Entry::Occupied(e) => { |
5568 | /// assert_eq!(e.key(), &"poneyland" ); |
5569 | /// assert_eq!(e.get(), &43); |
5570 | /// } |
5571 | /// Entry::Vacant(_) => panic!(), |
5572 | /// } |
5573 | /// |
5574 | /// assert_eq!(map["poneyland" ], 43); |
5575 | /// |
5576 | /// let entry = match map.entry("poneyland" ) { |
5577 | /// Entry::Occupied(e) => e.replace_entry_with(|_k, _v| None), |
5578 | /// Entry::Vacant(_) => panic!(), |
5579 | /// }; |
5580 | /// |
5581 | /// match entry { |
5582 | /// Entry::Vacant(e) => { |
5583 | /// assert_eq!(e.key(), &"poneyland" ); |
5584 | /// } |
5585 | /// Entry::Occupied(_) => panic!(), |
5586 | /// } |
5587 | /// |
5588 | /// assert!(!map.contains_key("poneyland" )); |
5589 | /// ``` |
5590 | #[cfg_attr (feature = "inline-more" , inline)] |
5591 | pub fn replace_entry_with<F>(self, f: F) -> Entry<'a, K, V, S, A> |
5592 | where |
5593 | F: FnOnce(&K, V) -> Option<V>, |
5594 | { |
5595 | unsafe { |
5596 | let mut spare_key = None; |
5597 | |
5598 | self.table |
5599 | .table |
5600 | .replace_bucket_with(self.elem.clone(), |(key, value)| { |
5601 | if let Some(new_value) = f(&key, value) { |
5602 | Some((key, new_value)) |
5603 | } else { |
5604 | spare_key = Some(key); |
5605 | None |
5606 | } |
5607 | }); |
5608 | |
5609 | if let Some(key) = spare_key { |
5610 | Entry::Vacant(VacantEntry { |
5611 | hash: self.hash, |
5612 | key, |
5613 | table: self.table, |
5614 | }) |
5615 | } else { |
5616 | Entry::Occupied(self) |
5617 | } |
5618 | } |
5619 | } |
5620 | } |
5621 | |
5622 | impl<'a, K, V, S, A: Allocator> VacantEntry<'a, K, V, S, A> { |
5623 | /// Gets a reference to the key that would be used when inserting a value |
5624 | /// through the `VacantEntry`. |
5625 | /// |
5626 | /// # Examples |
5627 | /// |
5628 | /// ``` |
5629 | /// use hashbrown::HashMap; |
5630 | /// |
5631 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5632 | /// assert_eq!(map.entry("poneyland" ).key(), &"poneyland" ); |
5633 | /// ``` |
5634 | #[cfg_attr (feature = "inline-more" , inline)] |
5635 | pub fn key(&self) -> &K { |
5636 | &self.key |
5637 | } |
5638 | |
5639 | /// Take ownership of the key. |
5640 | /// |
5641 | /// # Examples |
5642 | /// |
5643 | /// ``` |
5644 | /// use hashbrown::hash_map::{Entry, HashMap}; |
5645 | /// |
5646 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5647 | /// |
5648 | /// match map.entry("poneyland" ) { |
5649 | /// Entry::Occupied(_) => panic!(), |
5650 | /// Entry::Vacant(v) => assert_eq!(v.into_key(), "poneyland" ), |
5651 | /// } |
5652 | /// ``` |
5653 | #[cfg_attr (feature = "inline-more" , inline)] |
5654 | pub fn into_key(self) -> K { |
5655 | self.key |
5656 | } |
5657 | |
5658 | /// Sets the value of the entry with the VacantEntry's key, |
5659 | /// and returns a mutable reference to it. |
5660 | /// |
5661 | /// # Examples |
5662 | /// |
5663 | /// ``` |
5664 | /// use hashbrown::HashMap; |
5665 | /// use hashbrown::hash_map::Entry; |
5666 | /// |
5667 | /// let mut map: HashMap<&str, u32> = HashMap::new(); |
5668 | /// |
5669 | /// if let Entry::Vacant(o) = map.entry("poneyland" ) { |
5670 | /// o.insert(37); |
5671 | /// } |
5672 | /// assert_eq!(map["poneyland" ], 37); |
5673 | /// ``` |
5674 | #[cfg_attr (feature = "inline-more" , inline)] |
5675 | pub fn insert(self, value: V) -> &'a mut V |
5676 | where |
5677 | K: Hash, |
5678 | S: BuildHasher, |
5679 | { |
5680 | let table = &mut self.table.table; |
5681 | let entry = table.insert_entry( |
5682 | self.hash, |
5683 | (self.key, value), |
5684 | make_hasher::<_, V, S>(&self.table.hash_builder), |
5685 | ); |
5686 | &mut entry.1 |
5687 | } |
5688 | |
5689 | #[cfg_attr (feature = "inline-more" , inline)] |
5690 | pub(crate) fn insert_entry(self, value: V) -> OccupiedEntry<'a, K, V, S, A> |
5691 | where |
5692 | K: Hash, |
5693 | S: BuildHasher, |
5694 | { |
5695 | let elem = self.table.table.insert( |
5696 | self.hash, |
5697 | (self.key, value), |
5698 | make_hasher::<_, V, S>(&self.table.hash_builder), |
5699 | ); |
5700 | OccupiedEntry { |
5701 | hash: self.hash, |
5702 | key: None, |
5703 | elem, |
5704 | table: self.table, |
5705 | } |
5706 | } |
5707 | } |
5708 | |
5709 | impl<'a, 'b, K, Q: ?Sized, V, S, A: Allocator> EntryRef<'a, 'b, K, Q, V, S, A> { |
5710 | /// Sets the value of the entry, and returns an OccupiedEntryRef. |
5711 | /// |
5712 | /// # Examples |
5713 | /// |
5714 | /// ``` |
5715 | /// use hashbrown::HashMap; |
5716 | /// |
5717 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
5718 | /// let entry = map.entry_ref("horseyland" ).insert(37); |
5719 | /// |
5720 | /// assert_eq!(entry.key(), "horseyland" ); |
5721 | /// ``` |
5722 | #[cfg_attr (feature = "inline-more" , inline)] |
5723 | pub fn insert(self, value: V) -> OccupiedEntryRef<'a, 'b, K, Q, V, S, A> |
5724 | where |
5725 | K: Hash + From<&'b Q>, |
5726 | S: BuildHasher, |
5727 | { |
5728 | match self { |
5729 | EntryRef::Occupied(mut entry) => { |
5730 | entry.insert(value); |
5731 | entry |
5732 | } |
5733 | EntryRef::Vacant(entry) => entry.insert_entry(value), |
5734 | } |
5735 | } |
5736 | |
5737 | /// Ensures a value is in the entry by inserting the default if empty, and returns |
5738 | /// a mutable reference to the value in the entry. |
5739 | /// |
5740 | /// # Examples |
5741 | /// |
5742 | /// ``` |
5743 | /// use hashbrown::HashMap; |
5744 | /// |
5745 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
5746 | /// |
5747 | /// // nonexistent key |
5748 | /// map.entry_ref("poneyland" ).or_insert(3); |
5749 | /// assert_eq!(map["poneyland" ], 3); |
5750 | /// |
5751 | /// // existing key |
5752 | /// *map.entry_ref("poneyland" ).or_insert(10) *= 2; |
5753 | /// assert_eq!(map["poneyland" ], 6); |
5754 | /// ``` |
5755 | #[cfg_attr (feature = "inline-more" , inline)] |
5756 | pub fn or_insert(self, default: V) -> &'a mut V |
5757 | where |
5758 | K: Hash + From<&'b Q>, |
5759 | S: BuildHasher, |
5760 | { |
5761 | match self { |
5762 | EntryRef::Occupied(entry) => entry.into_mut(), |
5763 | EntryRef::Vacant(entry) => entry.insert(default), |
5764 | } |
5765 | } |
5766 | |
5767 | /// Ensures a value is in the entry by inserting the result of the default function if empty, |
5768 | /// and returns a mutable reference to the value in the entry. |
5769 | /// |
5770 | /// # Examples |
5771 | /// |
5772 | /// ``` |
5773 | /// use hashbrown::HashMap; |
5774 | /// |
5775 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
5776 | /// |
5777 | /// // nonexistent key |
5778 | /// map.entry_ref("poneyland" ).or_insert_with(|| 3); |
5779 | /// assert_eq!(map["poneyland" ], 3); |
5780 | /// |
5781 | /// // existing key |
5782 | /// *map.entry_ref("poneyland" ).or_insert_with(|| 10) *= 2; |
5783 | /// assert_eq!(map["poneyland" ], 6); |
5784 | /// ``` |
5785 | #[cfg_attr (feature = "inline-more" , inline)] |
5786 | pub fn or_insert_with<F: FnOnce() -> V>(self, default: F) -> &'a mut V |
5787 | where |
5788 | K: Hash + From<&'b Q>, |
5789 | S: BuildHasher, |
5790 | { |
5791 | match self { |
5792 | EntryRef::Occupied(entry) => entry.into_mut(), |
5793 | EntryRef::Vacant(entry) => entry.insert(default()), |
5794 | } |
5795 | } |
5796 | |
5797 | /// Ensures a value is in the entry by inserting, if empty, the result of the default function. |
5798 | /// This method allows for generating key-derived values for insertion by providing the default |
5799 | /// function an access to the borrower form of the key. |
5800 | /// |
5801 | /// # Examples |
5802 | /// |
5803 | /// ``` |
5804 | /// use hashbrown::HashMap; |
5805 | /// |
5806 | /// let mut map: HashMap<String, usize> = HashMap::new(); |
5807 | /// |
5808 | /// // nonexistent key |
5809 | /// map.entry_ref("poneyland" ).or_insert_with_key(|key| key.chars().count()); |
5810 | /// assert_eq!(map["poneyland" ], 9); |
5811 | /// |
5812 | /// // existing key |
5813 | /// *map.entry_ref("poneyland" ).or_insert_with_key(|key| key.chars().count() * 10) *= 2; |
5814 | /// assert_eq!(map["poneyland" ], 18); |
5815 | /// ``` |
5816 | #[cfg_attr (feature = "inline-more" , inline)] |
5817 | pub fn or_insert_with_key<F: FnOnce(&Q) -> V>(self, default: F) -> &'a mut V |
5818 | where |
5819 | K: Hash + Borrow<Q> + From<&'b Q>, |
5820 | S: BuildHasher, |
5821 | { |
5822 | match self { |
5823 | EntryRef::Occupied(entry) => entry.into_mut(), |
5824 | EntryRef::Vacant(entry) => { |
5825 | let value = default(entry.key.as_ref()); |
5826 | entry.insert(value) |
5827 | } |
5828 | } |
5829 | } |
5830 | |
5831 | /// Returns a reference to this entry's key. |
5832 | /// |
5833 | /// # Examples |
5834 | /// |
5835 | /// ``` |
5836 | /// use hashbrown::HashMap; |
5837 | /// |
5838 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
5839 | /// map.entry_ref("poneyland" ).or_insert(3); |
5840 | /// // existing key |
5841 | /// assert_eq!(map.entry_ref("poneyland" ).key(), "poneyland" ); |
5842 | /// // nonexistent key |
5843 | /// assert_eq!(map.entry_ref("horseland" ).key(), "horseland" ); |
5844 | /// ``` |
5845 | #[cfg_attr (feature = "inline-more" , inline)] |
5846 | pub fn key(&self) -> &Q |
5847 | where |
5848 | K: Borrow<Q>, |
5849 | { |
5850 | match *self { |
5851 | EntryRef::Occupied(ref entry) => entry.key().borrow(), |
5852 | EntryRef::Vacant(ref entry) => entry.key(), |
5853 | } |
5854 | } |
5855 | |
5856 | /// Provides in-place mutable access to an occupied entry before any |
5857 | /// potential inserts into the map. |
5858 | /// |
5859 | /// # Examples |
5860 | /// |
5861 | /// ``` |
5862 | /// use hashbrown::HashMap; |
5863 | /// |
5864 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
5865 | /// |
5866 | /// map.entry_ref("poneyland" ) |
5867 | /// .and_modify(|e| { *e += 1 }) |
5868 | /// .or_insert(42); |
5869 | /// assert_eq!(map["poneyland" ], 42); |
5870 | /// |
5871 | /// map.entry_ref("poneyland" ) |
5872 | /// .and_modify(|e| { *e += 1 }) |
5873 | /// .or_insert(42); |
5874 | /// assert_eq!(map["poneyland" ], 43); |
5875 | /// ``` |
5876 | #[cfg_attr (feature = "inline-more" , inline)] |
5877 | pub fn and_modify<F>(self, f: F) -> Self |
5878 | where |
5879 | F: FnOnce(&mut V), |
5880 | { |
5881 | match self { |
5882 | EntryRef::Occupied(mut entry) => { |
5883 | f(entry.get_mut()); |
5884 | EntryRef::Occupied(entry) |
5885 | } |
5886 | EntryRef::Vacant(entry) => EntryRef::Vacant(entry), |
5887 | } |
5888 | } |
5889 | |
5890 | /// Provides shared access to the key and owned access to the value of |
5891 | /// an occupied entry and allows to replace or remove it based on the |
5892 | /// value of the returned option. |
5893 | /// |
5894 | /// # Examples |
5895 | /// |
5896 | /// ``` |
5897 | /// use hashbrown::HashMap; |
5898 | /// use hashbrown::hash_map::EntryRef; |
5899 | /// |
5900 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
5901 | /// |
5902 | /// let entry = map |
5903 | /// .entry_ref("poneyland" ) |
5904 | /// .and_replace_entry_with(|_k, _v| panic!()); |
5905 | /// |
5906 | /// match entry { |
5907 | /// EntryRef::Vacant(e) => { |
5908 | /// assert_eq!(e.key(), "poneyland" ); |
5909 | /// } |
5910 | /// EntryRef::Occupied(_) => panic!(), |
5911 | /// } |
5912 | /// |
5913 | /// map.insert("poneyland" .to_string(), 42); |
5914 | /// |
5915 | /// let entry = map |
5916 | /// .entry_ref("poneyland" ) |
5917 | /// .and_replace_entry_with(|k, v| { |
5918 | /// assert_eq!(k, "poneyland" ); |
5919 | /// assert_eq!(v, 42); |
5920 | /// Some(v + 1) |
5921 | /// }); |
5922 | /// |
5923 | /// match entry { |
5924 | /// EntryRef::Occupied(e) => { |
5925 | /// assert_eq!(e.key(), "poneyland" ); |
5926 | /// assert_eq!(e.get(), &43); |
5927 | /// } |
5928 | /// EntryRef::Vacant(_) => panic!(), |
5929 | /// } |
5930 | /// |
5931 | /// assert_eq!(map["poneyland" ], 43); |
5932 | /// |
5933 | /// let entry = map |
5934 | /// .entry_ref("poneyland" ) |
5935 | /// .and_replace_entry_with(|_k, _v| None); |
5936 | /// |
5937 | /// match entry { |
5938 | /// EntryRef::Vacant(e) => assert_eq!(e.key(), "poneyland" ), |
5939 | /// EntryRef::Occupied(_) => panic!(), |
5940 | /// } |
5941 | /// |
5942 | /// assert!(!map.contains_key("poneyland" )); |
5943 | /// ``` |
5944 | #[cfg_attr (feature = "inline-more" , inline)] |
5945 | pub fn and_replace_entry_with<F>(self, f: F) -> Self |
5946 | where |
5947 | F: FnOnce(&K, V) -> Option<V>, |
5948 | { |
5949 | match self { |
5950 | EntryRef::Occupied(entry) => entry.replace_entry_with(f), |
5951 | EntryRef::Vacant(_) => self, |
5952 | } |
5953 | } |
5954 | } |
5955 | |
5956 | impl<'a, 'b, K, Q: ?Sized, V: Default, S, A: Allocator> EntryRef<'a, 'b, K, Q, V, S, A> { |
5957 | /// Ensures a value is in the entry by inserting the default value if empty, |
5958 | /// and returns a mutable reference to the value in the entry. |
5959 | /// |
5960 | /// # Examples |
5961 | /// |
5962 | /// ``` |
5963 | /// use hashbrown::HashMap; |
5964 | /// |
5965 | /// let mut map: HashMap<String, Option<u32>> = HashMap::new(); |
5966 | /// |
5967 | /// // nonexistent key |
5968 | /// map.entry_ref("poneyland" ).or_default(); |
5969 | /// assert_eq!(map["poneyland" ], None); |
5970 | /// |
5971 | /// map.insert("horseland" .to_string(), Some(3)); |
5972 | /// |
5973 | /// // existing key |
5974 | /// assert_eq!(map.entry_ref("horseland" ).or_default(), &mut Some(3)); |
5975 | /// ``` |
5976 | #[cfg_attr (feature = "inline-more" , inline)] |
5977 | pub fn or_default(self) -> &'a mut V |
5978 | where |
5979 | K: Hash + From<&'b Q>, |
5980 | S: BuildHasher, |
5981 | { |
5982 | match self { |
5983 | EntryRef::Occupied(entry) => entry.into_mut(), |
5984 | EntryRef::Vacant(entry) => entry.insert(Default::default()), |
5985 | } |
5986 | } |
5987 | } |
5988 | |
5989 | impl<'a, 'b, K, Q: ?Sized, V, S, A: Allocator> OccupiedEntryRef<'a, 'b, K, Q, V, S, A> { |
5990 | /// Gets a reference to the key in the entry. |
5991 | /// |
5992 | /// # Examples |
5993 | /// |
5994 | /// ``` |
5995 | /// use hashbrown::hash_map::{EntryRef, HashMap}; |
5996 | /// |
5997 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
5998 | /// map.entry_ref("poneyland" ).or_insert(12); |
5999 | /// |
6000 | /// match map.entry_ref("poneyland" ) { |
6001 | /// EntryRef::Vacant(_) => panic!(), |
6002 | /// EntryRef::Occupied(entry) => assert_eq!(entry.key(), "poneyland" ), |
6003 | /// } |
6004 | /// ``` |
6005 | #[cfg_attr (feature = "inline-more" , inline)] |
6006 | pub fn key(&self) -> &K { |
6007 | unsafe { &self.elem.as_ref().0 } |
6008 | } |
6009 | |
6010 | /// Take the ownership of the key and value from the map. |
6011 | /// Keeps the allocated memory for reuse. |
6012 | /// |
6013 | /// # Examples |
6014 | /// |
6015 | /// ``` |
6016 | /// use hashbrown::HashMap; |
6017 | /// use hashbrown::hash_map::EntryRef; |
6018 | /// |
6019 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6020 | /// // The map is empty |
6021 | /// assert!(map.is_empty() && map.capacity() == 0); |
6022 | /// |
6023 | /// map.entry_ref("poneyland" ).or_insert(12); |
6024 | /// |
6025 | /// if let EntryRef::Occupied(o) = map.entry_ref("poneyland" ) { |
6026 | /// // We delete the entry from the map. |
6027 | /// assert_eq!(o.remove_entry(), ("poneyland" .to_owned(), 12)); |
6028 | /// } |
6029 | /// |
6030 | /// assert_eq!(map.contains_key("poneyland" ), false); |
6031 | /// // Now map hold none elements but capacity is equal to the old one |
6032 | /// assert!(map.is_empty()); |
6033 | /// ``` |
6034 | #[cfg_attr (feature = "inline-more" , inline)] |
6035 | pub fn remove_entry(self) -> (K, V) { |
6036 | unsafe { self.table.table.remove(self.elem).0 } |
6037 | } |
6038 | |
6039 | /// Gets a reference to the value in the entry. |
6040 | /// |
6041 | /// # Examples |
6042 | /// |
6043 | /// ``` |
6044 | /// use hashbrown::HashMap; |
6045 | /// use hashbrown::hash_map::EntryRef; |
6046 | /// |
6047 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6048 | /// map.entry_ref("poneyland" ).or_insert(12); |
6049 | /// |
6050 | /// match map.entry_ref("poneyland" ) { |
6051 | /// EntryRef::Vacant(_) => panic!(), |
6052 | /// EntryRef::Occupied(entry) => assert_eq!(entry.get(), &12), |
6053 | /// } |
6054 | /// ``` |
6055 | #[cfg_attr (feature = "inline-more" , inline)] |
6056 | pub fn get(&self) -> &V { |
6057 | unsafe { &self.elem.as_ref().1 } |
6058 | } |
6059 | |
6060 | /// Gets a mutable reference to the value in the entry. |
6061 | /// |
6062 | /// If you need a reference to the `OccupiedEntryRef` which may outlive the |
6063 | /// destruction of the `EntryRef` value, see [`into_mut`]. |
6064 | /// |
6065 | /// [`into_mut`]: #method.into_mut |
6066 | /// |
6067 | /// # Examples |
6068 | /// |
6069 | /// ``` |
6070 | /// use hashbrown::HashMap; |
6071 | /// use hashbrown::hash_map::EntryRef; |
6072 | /// |
6073 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6074 | /// map.entry_ref("poneyland" ).or_insert(12); |
6075 | /// |
6076 | /// assert_eq!(map["poneyland" ], 12); |
6077 | /// if let EntryRef::Occupied(mut o) = map.entry_ref("poneyland" ) { |
6078 | /// *o.get_mut() += 10; |
6079 | /// assert_eq!(*o.get(), 22); |
6080 | /// |
6081 | /// // We can use the same Entry multiple times. |
6082 | /// *o.get_mut() += 2; |
6083 | /// } |
6084 | /// |
6085 | /// assert_eq!(map["poneyland" ], 24); |
6086 | /// ``` |
6087 | #[cfg_attr (feature = "inline-more" , inline)] |
6088 | pub fn get_mut(&mut self) -> &mut V { |
6089 | unsafe { &mut self.elem.as_mut().1 } |
6090 | } |
6091 | |
6092 | /// Converts the OccupiedEntryRef into a mutable reference to the value in the entry |
6093 | /// with a lifetime bound to the map itself. |
6094 | /// |
6095 | /// If you need multiple references to the `OccupiedEntryRef`, see [`get_mut`]. |
6096 | /// |
6097 | /// [`get_mut`]: #method.get_mut |
6098 | /// |
6099 | /// # Examples |
6100 | /// |
6101 | /// ``` |
6102 | /// use hashbrown::hash_map::{EntryRef, HashMap}; |
6103 | /// |
6104 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6105 | /// map.entry_ref("poneyland" ).or_insert(12); |
6106 | /// |
6107 | /// let value: &mut u32; |
6108 | /// match map.entry_ref("poneyland" ) { |
6109 | /// EntryRef::Occupied(entry) => value = entry.into_mut(), |
6110 | /// EntryRef::Vacant(_) => panic!(), |
6111 | /// } |
6112 | /// *value += 10; |
6113 | /// |
6114 | /// assert_eq!(map["poneyland" ], 22); |
6115 | /// ``` |
6116 | #[cfg_attr (feature = "inline-more" , inline)] |
6117 | pub fn into_mut(self) -> &'a mut V { |
6118 | unsafe { &mut self.elem.as_mut().1 } |
6119 | } |
6120 | |
6121 | /// Sets the value of the entry, and returns the entry's old value. |
6122 | /// |
6123 | /// # Examples |
6124 | /// |
6125 | /// ``` |
6126 | /// use hashbrown::HashMap; |
6127 | /// use hashbrown::hash_map::EntryRef; |
6128 | /// |
6129 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6130 | /// map.entry_ref("poneyland" ).or_insert(12); |
6131 | /// |
6132 | /// if let EntryRef::Occupied(mut o) = map.entry_ref("poneyland" ) { |
6133 | /// assert_eq!(o.insert(15), 12); |
6134 | /// } |
6135 | /// |
6136 | /// assert_eq!(map["poneyland" ], 15); |
6137 | /// ``` |
6138 | #[cfg_attr (feature = "inline-more" , inline)] |
6139 | pub fn insert(&mut self, value: V) -> V { |
6140 | mem::replace(self.get_mut(), value) |
6141 | } |
6142 | |
6143 | /// Takes the value out of the entry, and returns it. |
6144 | /// Keeps the allocated memory for reuse. |
6145 | /// |
6146 | /// # Examples |
6147 | /// |
6148 | /// ``` |
6149 | /// use hashbrown::HashMap; |
6150 | /// use hashbrown::hash_map::EntryRef; |
6151 | /// |
6152 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6153 | /// // The map is empty |
6154 | /// assert!(map.is_empty() && map.capacity() == 0); |
6155 | /// |
6156 | /// map.entry_ref("poneyland" ).or_insert(12); |
6157 | /// |
6158 | /// if let EntryRef::Occupied(o) = map.entry_ref("poneyland" ) { |
6159 | /// assert_eq!(o.remove(), 12); |
6160 | /// } |
6161 | /// |
6162 | /// assert_eq!(map.contains_key("poneyland" ), false); |
6163 | /// // Now map hold none elements but capacity is equal to the old one |
6164 | /// assert!(map.is_empty()); |
6165 | /// ``` |
6166 | #[cfg_attr (feature = "inline-more" , inline)] |
6167 | pub fn remove(self) -> V { |
6168 | self.remove_entry().1 |
6169 | } |
6170 | |
6171 | /// Replaces the entry, returning the old key and value. The new key in the hash map will be |
6172 | /// the key used to create this entry. |
6173 | /// |
6174 | /// # Panics |
6175 | /// |
6176 | /// Will panic if this OccupiedEntryRef was created through [`EntryRef::insert`]. |
6177 | /// |
6178 | /// # Examples |
6179 | /// |
6180 | /// ``` |
6181 | /// use hashbrown::hash_map::{EntryRef, HashMap}; |
6182 | /// use std::rc::Rc; |
6183 | /// |
6184 | /// let mut map: HashMap<Rc<str>, u32> = HashMap::new(); |
6185 | /// let key: Rc<str> = Rc::from("Stringthing" ); |
6186 | /// |
6187 | /// map.insert(key.clone(), 15); |
6188 | /// assert_eq!(Rc::strong_count(&key), 2); |
6189 | /// |
6190 | /// match map.entry_ref("Stringthing" ) { |
6191 | /// EntryRef::Occupied(entry) => { |
6192 | /// let (old_key, old_value): (Rc<str>, u32) = entry.replace_entry(16); |
6193 | /// assert!(Rc::ptr_eq(&key, &old_key) && old_value == 15); |
6194 | /// } |
6195 | /// EntryRef::Vacant(_) => panic!(), |
6196 | /// } |
6197 | /// |
6198 | /// assert_eq!(Rc::strong_count(&key), 1); |
6199 | /// assert_eq!(map["Stringthing" ], 16); |
6200 | /// ``` |
6201 | #[cfg_attr (feature = "inline-more" , inline)] |
6202 | pub fn replace_entry(self, value: V) -> (K, V) |
6203 | where |
6204 | K: From<&'b Q>, |
6205 | { |
6206 | let entry = unsafe { self.elem.as_mut() }; |
6207 | |
6208 | let old_key = mem::replace(&mut entry.0, self.key.unwrap().into_owned()); |
6209 | let old_value = mem::replace(&mut entry.1, value); |
6210 | |
6211 | (old_key, old_value) |
6212 | } |
6213 | |
6214 | /// Replaces the key in the hash map with the key used to create this entry. |
6215 | /// |
6216 | /// # Panics |
6217 | /// |
6218 | /// Will panic if this OccupiedEntryRef was created through [`EntryRef::insert`]. |
6219 | /// |
6220 | /// # Examples |
6221 | /// |
6222 | /// ``` |
6223 | /// use hashbrown::hash_map::{EntryRef, HashMap}; |
6224 | /// use std::rc::Rc; |
6225 | /// |
6226 | /// let mut map: HashMap<Rc<str>, usize> = HashMap::with_capacity(6); |
6227 | /// let mut keys: Vec<Rc<str>> = Vec::with_capacity(6); |
6228 | /// |
6229 | /// for (value, key) in ["a" , "b" , "c" , "d" , "e" , "f" ].into_iter().enumerate() { |
6230 | /// let rc_key: Rc<str> = Rc::from(key); |
6231 | /// keys.push(rc_key.clone()); |
6232 | /// map.insert(rc_key.clone(), value); |
6233 | /// } |
6234 | /// |
6235 | /// assert!(keys.iter().all(|key| Rc::strong_count(key) == 2)); |
6236 | /// |
6237 | /// // It doesn't matter that we kind of use a vector with the same keys, |
6238 | /// // because all keys will be newly created from the references |
6239 | /// reclaim_memory(&mut map, &keys); |
6240 | /// |
6241 | /// assert!(keys.iter().all(|key| Rc::strong_count(key) == 1)); |
6242 | /// |
6243 | /// fn reclaim_memory(map: &mut HashMap<Rc<str>, usize>, keys: &[Rc<str>]) { |
6244 | /// for key in keys { |
6245 | /// if let EntryRef::Occupied(entry) = map.entry_ref(key.as_ref()) { |
6246 | /// // Replaces the entry's key with our version of it in `keys`. |
6247 | /// entry.replace_key(); |
6248 | /// } |
6249 | /// } |
6250 | /// } |
6251 | /// ``` |
6252 | #[cfg_attr (feature = "inline-more" , inline)] |
6253 | pub fn replace_key(self) -> K |
6254 | where |
6255 | K: From<&'b Q>, |
6256 | { |
6257 | let entry = unsafe { self.elem.as_mut() }; |
6258 | mem::replace(&mut entry.0, self.key.unwrap().into_owned()) |
6259 | } |
6260 | |
6261 | /// Provides shared access to the key and owned access to the value of |
6262 | /// the entry and allows to replace or remove it based on the |
6263 | /// value of the returned option. |
6264 | /// |
6265 | /// # Examples |
6266 | /// |
6267 | /// ``` |
6268 | /// use hashbrown::HashMap; |
6269 | /// use hashbrown::hash_map::EntryRef; |
6270 | /// |
6271 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6272 | /// map.insert("poneyland" .to_string(), 42); |
6273 | /// |
6274 | /// let entry = match map.entry_ref("poneyland" ) { |
6275 | /// EntryRef::Occupied(e) => { |
6276 | /// e.replace_entry_with(|k, v| { |
6277 | /// assert_eq!(k, "poneyland" ); |
6278 | /// assert_eq!(v, 42); |
6279 | /// Some(v + 1) |
6280 | /// }) |
6281 | /// } |
6282 | /// EntryRef::Vacant(_) => panic!(), |
6283 | /// }; |
6284 | /// |
6285 | /// match entry { |
6286 | /// EntryRef::Occupied(e) => { |
6287 | /// assert_eq!(e.key(), "poneyland" ); |
6288 | /// assert_eq!(e.get(), &43); |
6289 | /// } |
6290 | /// EntryRef::Vacant(_) => panic!(), |
6291 | /// } |
6292 | /// |
6293 | /// assert_eq!(map["poneyland" ], 43); |
6294 | /// |
6295 | /// let entry = match map.entry_ref("poneyland" ) { |
6296 | /// EntryRef::Occupied(e) => e.replace_entry_with(|_k, _v| None), |
6297 | /// EntryRef::Vacant(_) => panic!(), |
6298 | /// }; |
6299 | /// |
6300 | /// match entry { |
6301 | /// EntryRef::Vacant(e) => { |
6302 | /// assert_eq!(e.key(), "poneyland" ); |
6303 | /// } |
6304 | /// EntryRef::Occupied(_) => panic!(), |
6305 | /// } |
6306 | /// |
6307 | /// assert!(!map.contains_key("poneyland" )); |
6308 | /// ``` |
6309 | #[cfg_attr (feature = "inline-more" , inline)] |
6310 | pub fn replace_entry_with<F>(self, f: F) -> EntryRef<'a, 'b, K, Q, V, S, A> |
6311 | where |
6312 | F: FnOnce(&K, V) -> Option<V>, |
6313 | { |
6314 | unsafe { |
6315 | let mut spare_key = None; |
6316 | |
6317 | self.table |
6318 | .table |
6319 | .replace_bucket_with(self.elem.clone(), |(key, value)| { |
6320 | if let Some(new_value) = f(&key, value) { |
6321 | Some((key, new_value)) |
6322 | } else { |
6323 | spare_key = Some(KeyOrRef::Owned(key)); |
6324 | None |
6325 | } |
6326 | }); |
6327 | |
6328 | if let Some(key) = spare_key { |
6329 | EntryRef::Vacant(VacantEntryRef { |
6330 | hash: self.hash, |
6331 | key, |
6332 | table: self.table, |
6333 | }) |
6334 | } else { |
6335 | EntryRef::Occupied(self) |
6336 | } |
6337 | } |
6338 | } |
6339 | } |
6340 | |
6341 | impl<'a, 'b, K, Q: ?Sized, V, S, A: Allocator> VacantEntryRef<'a, 'b, K, Q, V, S, A> { |
6342 | /// Gets a reference to the key that would be used when inserting a value |
6343 | /// through the `VacantEntryRef`. |
6344 | /// |
6345 | /// # Examples |
6346 | /// |
6347 | /// ``` |
6348 | /// use hashbrown::HashMap; |
6349 | /// |
6350 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6351 | /// let key: &str = "poneyland" ; |
6352 | /// assert_eq!(map.entry_ref(key).key(), "poneyland" ); |
6353 | /// ``` |
6354 | #[cfg_attr (feature = "inline-more" , inline)] |
6355 | pub fn key(&self) -> &Q |
6356 | where |
6357 | K: Borrow<Q>, |
6358 | { |
6359 | self.key.as_ref() |
6360 | } |
6361 | |
6362 | /// Take ownership of the key. |
6363 | /// |
6364 | /// # Examples |
6365 | /// |
6366 | /// ``` |
6367 | /// use hashbrown::hash_map::{EntryRef, HashMap}; |
6368 | /// |
6369 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6370 | /// let key: &str = "poneyland" ; |
6371 | /// |
6372 | /// match map.entry_ref(key) { |
6373 | /// EntryRef::Occupied(_) => panic!(), |
6374 | /// EntryRef::Vacant(v) => assert_eq!(v.into_key(), "poneyland" .to_owned()), |
6375 | /// } |
6376 | /// ``` |
6377 | #[cfg_attr (feature = "inline-more" , inline)] |
6378 | pub fn into_key(self) -> K |
6379 | where |
6380 | K: From<&'b Q>, |
6381 | { |
6382 | self.key.into_owned() |
6383 | } |
6384 | |
6385 | /// Sets the value of the entry with the VacantEntryRef's key, |
6386 | /// and returns a mutable reference to it. |
6387 | /// |
6388 | /// # Examples |
6389 | /// |
6390 | /// ``` |
6391 | /// use hashbrown::HashMap; |
6392 | /// use hashbrown::hash_map::EntryRef; |
6393 | /// |
6394 | /// let mut map: HashMap<String, u32> = HashMap::new(); |
6395 | /// let key: &str = "poneyland" ; |
6396 | /// |
6397 | /// if let EntryRef::Vacant(o) = map.entry_ref(key) { |
6398 | /// o.insert(37); |
6399 | /// } |
6400 | /// assert_eq!(map["poneyland" ], 37); |
6401 | /// ``` |
6402 | #[cfg_attr (feature = "inline-more" , inline)] |
6403 | pub fn insert(self, value: V) -> &'a mut V |
6404 | where |
6405 | K: Hash + From<&'b Q>, |
6406 | S: BuildHasher, |
6407 | { |
6408 | let table = &mut self.table.table; |
6409 | let entry = table.insert_entry( |
6410 | self.hash, |
6411 | (self.key.into_owned(), value), |
6412 | make_hasher::<_, V, S>(&self.table.hash_builder), |
6413 | ); |
6414 | &mut entry.1 |
6415 | } |
6416 | |
6417 | #[cfg_attr (feature = "inline-more" , inline)] |
6418 | fn insert_entry(self, value: V) -> OccupiedEntryRef<'a, 'b, K, Q, V, S, A> |
6419 | where |
6420 | K: Hash + From<&'b Q>, |
6421 | S: BuildHasher, |
6422 | { |
6423 | let elem = self.table.table.insert( |
6424 | self.hash, |
6425 | (self.key.into_owned(), value), |
6426 | make_hasher::<_, V, S>(&self.table.hash_builder), |
6427 | ); |
6428 | OccupiedEntryRef { |
6429 | hash: self.hash, |
6430 | key: None, |
6431 | elem, |
6432 | table: self.table, |
6433 | } |
6434 | } |
6435 | } |
6436 | |
6437 | impl<K, V, S, A> FromIterator<(K, V)> for HashMap<K, V, S, A> |
6438 | where |
6439 | K: Eq + Hash, |
6440 | S: BuildHasher + Default, |
6441 | A: Default + Allocator, |
6442 | { |
6443 | #[cfg_attr (feature = "inline-more" , inline)] |
6444 | fn from_iter<T: IntoIterator<Item = (K, V)>>(iter: T) -> Self { |
6445 | let iter = iter.into_iter(); |
6446 | let mut map: HashMap = |
6447 | Self::with_capacity_and_hasher_in(capacity:iter.size_hint().0, S::default(), A::default()); |
6448 | iter.for_each(|(k: K, v: V)| { |
6449 | map.insert(k, v); |
6450 | }); |
6451 | map |
6452 | } |
6453 | } |
6454 | |
6455 | /// Inserts all new key-values from the iterator and replaces values with existing |
6456 | /// keys with new values returned from the iterator. |
6457 | impl<K, V, S, A> Extend<(K, V)> for HashMap<K, V, S, A> |
6458 | where |
6459 | K: Eq + Hash, |
6460 | S: BuildHasher, |
6461 | A: Allocator, |
6462 | { |
6463 | /// Inserts all new key-values from the iterator to existing `HashMap<K, V, S, A>`. |
6464 | /// Replace values with existing keys with new values returned from the iterator. |
6465 | /// |
6466 | /// # Examples |
6467 | /// |
6468 | /// ``` |
6469 | /// use hashbrown::hash_map::HashMap; |
6470 | /// |
6471 | /// let mut map = HashMap::new(); |
6472 | /// map.insert(1, 100); |
6473 | /// |
6474 | /// let some_iter = [(1, 1), (2, 2)].into_iter(); |
6475 | /// map.extend(some_iter); |
6476 | /// // Replace values with existing keys with new values returned from the iterator. |
6477 | /// // So that the map.get(&1) doesn't return Some(&100). |
6478 | /// assert_eq!(map.get(&1), Some(&1)); |
6479 | /// |
6480 | /// let some_vec: Vec<_> = vec![(3, 3), (4, 4)]; |
6481 | /// map.extend(some_vec); |
6482 | /// |
6483 | /// let some_arr = [(5, 5), (6, 6)]; |
6484 | /// map.extend(some_arr); |
6485 | /// let old_map_len = map.len(); |
6486 | /// |
6487 | /// // You can also extend from another HashMap |
6488 | /// let mut new_map = HashMap::new(); |
6489 | /// new_map.extend(map); |
6490 | /// assert_eq!(new_map.len(), old_map_len); |
6491 | /// |
6492 | /// let mut vec: Vec<_> = new_map.into_iter().collect(); |
6493 | /// // The `IntoIter` iterator produces items in arbitrary order, so the |
6494 | /// // items must be sorted to test them against a sorted array. |
6495 | /// vec.sort_unstable(); |
6496 | /// assert_eq!(vec, [(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)]); |
6497 | /// ``` |
6498 | #[cfg_attr (feature = "inline-more" , inline)] |
6499 | fn extend<T: IntoIterator<Item = (K, V)>>(&mut self, iter: T) { |
6500 | // Keys may be already present or show multiple times in the iterator. |
6501 | // Reserve the entire hint lower bound if the map is empty. |
6502 | // Otherwise reserve half the hint (rounded up), so the map |
6503 | // will only resize twice in the worst case. |
6504 | let iter = iter.into_iter(); |
6505 | let reserve = if self.is_empty() { |
6506 | iter.size_hint().0 |
6507 | } else { |
6508 | (iter.size_hint().0 + 1) / 2 |
6509 | }; |
6510 | self.reserve(reserve); |
6511 | iter.for_each(move |(k, v)| { |
6512 | self.insert(k, v); |
6513 | }); |
6514 | } |
6515 | |
6516 | #[inline ] |
6517 | #[cfg (feature = "nightly" )] |
6518 | fn extend_one(&mut self, (k, v): (K, V)) { |
6519 | self.insert(k, v); |
6520 | } |
6521 | |
6522 | #[inline ] |
6523 | #[cfg (feature = "nightly" )] |
6524 | fn extend_reserve(&mut self, additional: usize) { |
6525 | // Keys may be already present or show multiple times in the iterator. |
6526 | // Reserve the entire hint lower bound if the map is empty. |
6527 | // Otherwise reserve half the hint (rounded up), so the map |
6528 | // will only resize twice in the worst case. |
6529 | let reserve = if self.is_empty() { |
6530 | additional |
6531 | } else { |
6532 | (additional + 1) / 2 |
6533 | }; |
6534 | self.reserve(reserve); |
6535 | } |
6536 | } |
6537 | |
6538 | /// Inserts all new key-values from the iterator and replaces values with existing |
6539 | /// keys with new values returned from the iterator. |
6540 | impl<'a, K, V, S, A> Extend<(&'a K, &'a V)> for HashMap<K, V, S, A> |
6541 | where |
6542 | K: Eq + Hash + Copy, |
6543 | V: Copy, |
6544 | S: BuildHasher, |
6545 | A: Allocator, |
6546 | { |
6547 | /// Inserts all new key-values from the iterator to existing `HashMap<K, V, S, A>`. |
6548 | /// Replace values with existing keys with new values returned from the iterator. |
6549 | /// The keys and values must implement [`Copy`] trait. |
6550 | /// |
6551 | /// [`Copy`]: https://doc.rust-lang.org/core/marker/trait.Copy.html |
6552 | /// |
6553 | /// # Examples |
6554 | /// |
6555 | /// ``` |
6556 | /// use hashbrown::hash_map::HashMap; |
6557 | /// |
6558 | /// let mut map = HashMap::new(); |
6559 | /// map.insert(1, 100); |
6560 | /// |
6561 | /// let arr = [(1, 1), (2, 2)]; |
6562 | /// let some_iter = arr.iter().map(|(k, v)| (k, v)); |
6563 | /// map.extend(some_iter); |
6564 | /// // Replace values with existing keys with new values returned from the iterator. |
6565 | /// // So that the map.get(&1) doesn't return Some(&100). |
6566 | /// assert_eq!(map.get(&1), Some(&1)); |
6567 | /// |
6568 | /// let some_vec: Vec<_> = vec![(3, 3), (4, 4)]; |
6569 | /// map.extend(some_vec.iter().map(|(k, v)| (k, v))); |
6570 | /// |
6571 | /// let some_arr = [(5, 5), (6, 6)]; |
6572 | /// map.extend(some_arr.iter().map(|(k, v)| (k, v))); |
6573 | /// |
6574 | /// // You can also extend from another HashMap |
6575 | /// let mut new_map = HashMap::new(); |
6576 | /// new_map.extend(&map); |
6577 | /// assert_eq!(new_map, map); |
6578 | /// |
6579 | /// let mut vec: Vec<_> = new_map.into_iter().collect(); |
6580 | /// // The `IntoIter` iterator produces items in arbitrary order, so the |
6581 | /// // items must be sorted to test them against a sorted array. |
6582 | /// vec.sort_unstable(); |
6583 | /// assert_eq!(vec, [(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)]); |
6584 | /// ``` |
6585 | #[cfg_attr (feature = "inline-more" , inline)] |
6586 | fn extend<T: IntoIterator<Item = (&'a K, &'a V)>>(&mut self, iter: T) { |
6587 | self.extend(iter.into_iter().map(|(&key, &value)| (key, value))); |
6588 | } |
6589 | |
6590 | #[inline ] |
6591 | #[cfg (feature = "nightly" )] |
6592 | fn extend_one(&mut self, (k, v): (&'a K, &'a V)) { |
6593 | self.insert(*k, *v); |
6594 | } |
6595 | |
6596 | #[inline ] |
6597 | #[cfg (feature = "nightly" )] |
6598 | fn extend_reserve(&mut self, additional: usize) { |
6599 | Extend::<(K, V)>::extend_reserve(self, additional); |
6600 | } |
6601 | } |
6602 | |
6603 | /// Inserts all new key-values from the iterator and replaces values with existing |
6604 | /// keys with new values returned from the iterator. |
6605 | impl<'a, K, V, S, A> Extend<&'a (K, V)> for HashMap<K, V, S, A> |
6606 | where |
6607 | K: Eq + Hash + Copy, |
6608 | V: Copy, |
6609 | S: BuildHasher, |
6610 | A: Allocator, |
6611 | { |
6612 | /// Inserts all new key-values from the iterator to existing `HashMap<K, V, S, A>`. |
6613 | /// Replace values with existing keys with new values returned from the iterator. |
6614 | /// The keys and values must implement [`Copy`] trait. |
6615 | /// |
6616 | /// [`Copy`]: https://doc.rust-lang.org/core/marker/trait.Copy.html |
6617 | /// |
6618 | /// # Examples |
6619 | /// |
6620 | /// ``` |
6621 | /// use hashbrown::hash_map::HashMap; |
6622 | /// |
6623 | /// let mut map = HashMap::new(); |
6624 | /// map.insert(1, 100); |
6625 | /// |
6626 | /// let arr = [(1, 1), (2, 2)]; |
6627 | /// let some_iter = arr.iter(); |
6628 | /// map.extend(some_iter); |
6629 | /// // Replace values with existing keys with new values returned from the iterator. |
6630 | /// // So that the map.get(&1) doesn't return Some(&100). |
6631 | /// assert_eq!(map.get(&1), Some(&1)); |
6632 | /// |
6633 | /// let some_vec: Vec<_> = vec![(3, 3), (4, 4)]; |
6634 | /// map.extend(&some_vec); |
6635 | /// |
6636 | /// let some_arr = [(5, 5), (6, 6)]; |
6637 | /// map.extend(&some_arr); |
6638 | /// |
6639 | /// let mut vec: Vec<_> = map.into_iter().collect(); |
6640 | /// // The `IntoIter` iterator produces items in arbitrary order, so the |
6641 | /// // items must be sorted to test them against a sorted array. |
6642 | /// vec.sort_unstable(); |
6643 | /// assert_eq!(vec, [(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)]); |
6644 | /// ``` |
6645 | #[cfg_attr (feature = "inline-more" , inline)] |
6646 | fn extend<T: IntoIterator<Item = &'a (K, V)>>(&mut self, iter: T) { |
6647 | self.extend(iter.into_iter().map(|&(key, value)| (key, value))); |
6648 | } |
6649 | |
6650 | #[inline ] |
6651 | #[cfg (feature = "nightly" )] |
6652 | fn extend_one(&mut self, &(k, v): &'a (K, V)) { |
6653 | self.insert(k, v); |
6654 | } |
6655 | |
6656 | #[inline ] |
6657 | #[cfg (feature = "nightly" )] |
6658 | fn extend_reserve(&mut self, additional: usize) { |
6659 | Extend::<(K, V)>::extend_reserve(self, additional); |
6660 | } |
6661 | } |
6662 | |
6663 | #[allow (dead_code)] |
6664 | fn assert_covariance() { |
6665 | fn map_key<'new>(v: HashMap<&'static str, u8>) -> HashMap<&'new str, u8> { |
6666 | v |
6667 | } |
6668 | fn map_val<'new>(v: HashMap<u8, &'static str>) -> HashMap<u8, &'new str> { |
6669 | v |
6670 | } |
6671 | fn iter_key<'a, 'new>(v: Iter<'a, &'static str, u8>) -> Iter<'a, &'new str, u8> { |
6672 | v |
6673 | } |
6674 | fn iter_val<'a, 'new>(v: Iter<'a, u8, &'static str>) -> Iter<'a, u8, &'new str> { |
6675 | v |
6676 | } |
6677 | fn into_iter_key<'new, A: Allocator>( |
6678 | v: IntoIter<&'static str, u8, A>, |
6679 | ) -> IntoIter<&'new str, u8, A> { |
6680 | v |
6681 | } |
6682 | fn into_iter_val<'new, A: Allocator>( |
6683 | v: IntoIter<u8, &'static str, A>, |
6684 | ) -> IntoIter<u8, &'new str, A> { |
6685 | v |
6686 | } |
6687 | fn keys_key<'a, 'new>(v: Keys<'a, &'static str, u8>) -> Keys<'a, &'new str, u8> { |
6688 | v |
6689 | } |
6690 | fn keys_val<'a, 'new>(v: Keys<'a, u8, &'static str>) -> Keys<'a, u8, &'new str> { |
6691 | v |
6692 | } |
6693 | fn values_key<'a, 'new>(v: Values<'a, &'static str, u8>) -> Values<'a, &'new str, u8> { |
6694 | v |
6695 | } |
6696 | fn values_val<'a, 'new>(v: Values<'a, u8, &'static str>) -> Values<'a, u8, &'new str> { |
6697 | v |
6698 | } |
6699 | fn drain<'new>( |
6700 | d: Drain<'static, &'static str, &'static str>, |
6701 | ) -> Drain<'new, &'new str, &'new str> { |
6702 | d |
6703 | } |
6704 | } |
6705 | |
6706 | #[cfg (test)] |
6707 | mod test_map { |
6708 | use super::DefaultHashBuilder; |
6709 | use super::Entry::{Occupied, Vacant}; |
6710 | use super::EntryRef; |
6711 | use super::{HashMap, RawEntryMut}; |
6712 | use alloc::string::{String, ToString}; |
6713 | use alloc::sync::Arc; |
6714 | use allocator_api2::alloc::{AllocError, Allocator, Global}; |
6715 | use core::alloc::Layout; |
6716 | use core::ptr::NonNull; |
6717 | use core::sync::atomic::{AtomicI8, Ordering}; |
6718 | use rand::{rngs::SmallRng, Rng, SeedableRng}; |
6719 | use std::borrow::ToOwned; |
6720 | use std::cell::RefCell; |
6721 | use std::usize; |
6722 | use std::vec::Vec; |
6723 | |
6724 | #[test] |
6725 | fn test_zero_capacities() { |
6726 | type HM = HashMap<i32, i32>; |
6727 | |
6728 | let m = HM::new(); |
6729 | assert_eq!(m.capacity(), 0); |
6730 | |
6731 | let m = HM::default(); |
6732 | assert_eq!(m.capacity(), 0); |
6733 | |
6734 | let m = HM::with_hasher(DefaultHashBuilder::default()); |
6735 | assert_eq!(m.capacity(), 0); |
6736 | |
6737 | let m = HM::with_capacity(0); |
6738 | assert_eq!(m.capacity(), 0); |
6739 | |
6740 | let m = HM::with_capacity_and_hasher(0, DefaultHashBuilder::default()); |
6741 | assert_eq!(m.capacity(), 0); |
6742 | |
6743 | let mut m = HM::new(); |
6744 | m.insert(1, 1); |
6745 | m.insert(2, 2); |
6746 | m.remove(&1); |
6747 | m.remove(&2); |
6748 | m.shrink_to_fit(); |
6749 | assert_eq!(m.capacity(), 0); |
6750 | |
6751 | let mut m = HM::new(); |
6752 | m.reserve(0); |
6753 | assert_eq!(m.capacity(), 0); |
6754 | } |
6755 | |
6756 | #[test] |
6757 | fn test_create_capacity_zero() { |
6758 | let mut m = HashMap::with_capacity(0); |
6759 | |
6760 | assert!(m.insert(1, 1).is_none()); |
6761 | |
6762 | assert!(m.contains_key(&1)); |
6763 | assert!(!m.contains_key(&0)); |
6764 | } |
6765 | |
6766 | #[test] |
6767 | fn test_insert() { |
6768 | let mut m = HashMap::new(); |
6769 | assert_eq!(m.len(), 0); |
6770 | assert!(m.insert(1, 2).is_none()); |
6771 | assert_eq!(m.len(), 1); |
6772 | assert!(m.insert(2, 4).is_none()); |
6773 | assert_eq!(m.len(), 2); |
6774 | assert_eq!(*m.get(&1).unwrap(), 2); |
6775 | assert_eq!(*m.get(&2).unwrap(), 4); |
6776 | } |
6777 | |
6778 | #[test] |
6779 | fn test_clone() { |
6780 | let mut m = HashMap::new(); |
6781 | assert_eq!(m.len(), 0); |
6782 | assert!(m.insert(1, 2).is_none()); |
6783 | assert_eq!(m.len(), 1); |
6784 | assert!(m.insert(2, 4).is_none()); |
6785 | assert_eq!(m.len(), 2); |
6786 | #[allow (clippy::redundant_clone)] |
6787 | let m2 = m.clone(); |
6788 | assert_eq!(*m2.get(&1).unwrap(), 2); |
6789 | assert_eq!(*m2.get(&2).unwrap(), 4); |
6790 | assert_eq!(m2.len(), 2); |
6791 | } |
6792 | |
6793 | #[test] |
6794 | fn test_clone_from() { |
6795 | let mut m = HashMap::new(); |
6796 | let mut m2 = HashMap::new(); |
6797 | assert_eq!(m.len(), 0); |
6798 | assert!(m.insert(1, 2).is_none()); |
6799 | assert_eq!(m.len(), 1); |
6800 | assert!(m.insert(2, 4).is_none()); |
6801 | assert_eq!(m.len(), 2); |
6802 | m2.clone_from(&m); |
6803 | assert_eq!(*m2.get(&1).unwrap(), 2); |
6804 | assert_eq!(*m2.get(&2).unwrap(), 4); |
6805 | assert_eq!(m2.len(), 2); |
6806 | } |
6807 | |
6808 | thread_local! { static DROP_VECTOR: RefCell<Vec<i32>> = RefCell::new(Vec::new()) } |
6809 | |
6810 | #[derive(Hash, PartialEq, Eq)] |
6811 | struct Droppable { |
6812 | k: usize, |
6813 | } |
6814 | |
6815 | impl Droppable { |
6816 | fn new(k: usize) -> Droppable { |
6817 | DROP_VECTOR.with(|slot| { |
6818 | slot.borrow_mut()[k] += 1; |
6819 | }); |
6820 | |
6821 | Droppable { k } |
6822 | } |
6823 | } |
6824 | |
6825 | impl Drop for Droppable { |
6826 | fn drop(&mut self) { |
6827 | DROP_VECTOR.with(|slot| { |
6828 | slot.borrow_mut()[self.k] -= 1; |
6829 | }); |
6830 | } |
6831 | } |
6832 | |
6833 | impl Clone for Droppable { |
6834 | fn clone(&self) -> Self { |
6835 | Droppable::new(self.k) |
6836 | } |
6837 | } |
6838 | |
6839 | #[test] |
6840 | fn test_drops() { |
6841 | DROP_VECTOR.with(|slot| { |
6842 | *slot.borrow_mut() = vec![0; 200]; |
6843 | }); |
6844 | |
6845 | { |
6846 | let mut m = HashMap::new(); |
6847 | |
6848 | DROP_VECTOR.with(|v| { |
6849 | for i in 0..200 { |
6850 | assert_eq!(v.borrow()[i], 0); |
6851 | } |
6852 | }); |
6853 | |
6854 | for i in 0..100 { |
6855 | let d1 = Droppable::new(i); |
6856 | let d2 = Droppable::new(i + 100); |
6857 | m.insert(d1, d2); |
6858 | } |
6859 | |
6860 | DROP_VECTOR.with(|v| { |
6861 | for i in 0..200 { |
6862 | assert_eq!(v.borrow()[i], 1); |
6863 | } |
6864 | }); |
6865 | |
6866 | for i in 0..50 { |
6867 | let k = Droppable::new(i); |
6868 | let v = m.remove(&k); |
6869 | |
6870 | assert!(v.is_some()); |
6871 | |
6872 | DROP_VECTOR.with(|v| { |
6873 | assert_eq!(v.borrow()[i], 1); |
6874 | assert_eq!(v.borrow()[i + 100], 1); |
6875 | }); |
6876 | } |
6877 | |
6878 | DROP_VECTOR.with(|v| { |
6879 | for i in 0..50 { |
6880 | assert_eq!(v.borrow()[i], 0); |
6881 | assert_eq!(v.borrow()[i + 100], 0); |
6882 | } |
6883 | |
6884 | for i in 50..100 { |
6885 | assert_eq!(v.borrow()[i], 1); |
6886 | assert_eq!(v.borrow()[i + 100], 1); |
6887 | } |
6888 | }); |
6889 | } |
6890 | |
6891 | DROP_VECTOR.with(|v| { |
6892 | for i in 0..200 { |
6893 | assert_eq!(v.borrow()[i], 0); |
6894 | } |
6895 | }); |
6896 | } |
6897 | |
6898 | #[test] |
6899 | fn test_into_iter_drops() { |
6900 | DROP_VECTOR.with(|v| { |
6901 | *v.borrow_mut() = vec![0; 200]; |
6902 | }); |
6903 | |
6904 | let hm = { |
6905 | let mut hm = HashMap::new(); |
6906 | |
6907 | DROP_VECTOR.with(|v| { |
6908 | for i in 0..200 { |
6909 | assert_eq!(v.borrow()[i], 0); |
6910 | } |
6911 | }); |
6912 | |
6913 | for i in 0..100 { |
6914 | let d1 = Droppable::new(i); |
6915 | let d2 = Droppable::new(i + 100); |
6916 | hm.insert(d1, d2); |
6917 | } |
6918 | |
6919 | DROP_VECTOR.with(|v| { |
6920 | for i in 0..200 { |
6921 | assert_eq!(v.borrow()[i], 1); |
6922 | } |
6923 | }); |
6924 | |
6925 | hm |
6926 | }; |
6927 | |
6928 | // By the way, ensure that cloning doesn't screw up the dropping. |
6929 | drop(hm.clone()); |
6930 | |
6931 | { |
6932 | let mut half = hm.into_iter().take(50); |
6933 | |
6934 | DROP_VECTOR.with(|v| { |
6935 | for i in 0..200 { |
6936 | assert_eq!(v.borrow()[i], 1); |
6937 | } |
6938 | }); |
6939 | |
6940 | for _ in half.by_ref() {} |
6941 | |
6942 | DROP_VECTOR.with(|v| { |
6943 | let nk = (0..100).filter(|&i| v.borrow()[i] == 1).count(); |
6944 | |
6945 | let nv = (0..100).filter(|&i| v.borrow()[i + 100] == 1).count(); |
6946 | |
6947 | assert_eq!(nk, 50); |
6948 | assert_eq!(nv, 50); |
6949 | }); |
6950 | }; |
6951 | |
6952 | DROP_VECTOR.with(|v| { |
6953 | for i in 0..200 { |
6954 | assert_eq!(v.borrow()[i], 0); |
6955 | } |
6956 | }); |
6957 | } |
6958 | |
6959 | #[test] |
6960 | fn test_empty_remove() { |
6961 | let mut m: HashMap<i32, bool> = HashMap::new(); |
6962 | assert_eq!(m.remove(&0), None); |
6963 | } |
6964 | |
6965 | #[test] |
6966 | fn test_empty_entry() { |
6967 | let mut m: HashMap<i32, bool> = HashMap::new(); |
6968 | match m.entry(0) { |
6969 | Occupied(_) => panic!(), |
6970 | Vacant(_) => {} |
6971 | } |
6972 | assert!(*m.entry(0).or_insert(true)); |
6973 | assert_eq!(m.len(), 1); |
6974 | } |
6975 | |
6976 | #[test] |
6977 | fn test_empty_entry_ref() { |
6978 | let mut m: HashMap<std::string::String, bool> = HashMap::new(); |
6979 | match m.entry_ref("poneyland" ) { |
6980 | EntryRef::Occupied(_) => panic!(), |
6981 | EntryRef::Vacant(_) => {} |
6982 | } |
6983 | assert!(*m.entry_ref("poneyland" ).or_insert(true)); |
6984 | assert_eq!(m.len(), 1); |
6985 | } |
6986 | |
6987 | #[test] |
6988 | fn test_empty_iter() { |
6989 | let mut m: HashMap<i32, bool> = HashMap::new(); |
6990 | assert_eq!(m.drain().next(), None); |
6991 | assert_eq!(m.keys().next(), None); |
6992 | assert_eq!(m.values().next(), None); |
6993 | assert_eq!(m.values_mut().next(), None); |
6994 | assert_eq!(m.iter().next(), None); |
6995 | assert_eq!(m.iter_mut().next(), None); |
6996 | assert_eq!(m.len(), 0); |
6997 | assert!(m.is_empty()); |
6998 | assert_eq!(m.into_iter().next(), None); |
6999 | } |
7000 | |
7001 | #[test] |
7002 | #[cfg_attr (miri, ignore)] // FIXME: takes too long |
7003 | fn test_lots_of_insertions() { |
7004 | let mut m = HashMap::new(); |
7005 | |
7006 | // Try this a few times to make sure we never screw up the hashmap's |
7007 | // internal state. |
7008 | for _ in 0..10 { |
7009 | assert!(m.is_empty()); |
7010 | |
7011 | for i in 1..1001 { |
7012 | assert!(m.insert(i, i).is_none()); |
7013 | |
7014 | for j in 1..=i { |
7015 | let r = m.get(&j); |
7016 | assert_eq!(r, Some(&j)); |
7017 | } |
7018 | |
7019 | for j in i + 1..1001 { |
7020 | let r = m.get(&j); |
7021 | assert_eq!(r, None); |
7022 | } |
7023 | } |
7024 | |
7025 | for i in 1001..2001 { |
7026 | assert!(!m.contains_key(&i)); |
7027 | } |
7028 | |
7029 | // remove forwards |
7030 | for i in 1..1001 { |
7031 | assert!(m.remove(&i).is_some()); |
7032 | |
7033 | for j in 1..=i { |
7034 | assert!(!m.contains_key(&j)); |
7035 | } |
7036 | |
7037 | for j in i + 1..1001 { |
7038 | assert!(m.contains_key(&j)); |
7039 | } |
7040 | } |
7041 | |
7042 | for i in 1..1001 { |
7043 | assert!(!m.contains_key(&i)); |
7044 | } |
7045 | |
7046 | for i in 1..1001 { |
7047 | assert!(m.insert(i, i).is_none()); |
7048 | } |
7049 | |
7050 | // remove backwards |
7051 | for i in (1..1001).rev() { |
7052 | assert!(m.remove(&i).is_some()); |
7053 | |
7054 | for j in i..1001 { |
7055 | assert!(!m.contains_key(&j)); |
7056 | } |
7057 | |
7058 | for j in 1..i { |
7059 | assert!(m.contains_key(&j)); |
7060 | } |
7061 | } |
7062 | } |
7063 | } |
7064 | |
7065 | #[test] |
7066 | fn test_find_mut() { |
7067 | let mut m = HashMap::new(); |
7068 | assert!(m.insert(1, 12).is_none()); |
7069 | assert!(m.insert(2, 8).is_none()); |
7070 | assert!(m.insert(5, 14).is_none()); |
7071 | let new = 100; |
7072 | match m.get_mut(&5) { |
7073 | None => panic!(), |
7074 | Some(x) => *x = new, |
7075 | } |
7076 | assert_eq!(m.get(&5), Some(&new)); |
7077 | } |
7078 | |
7079 | #[test] |
7080 | fn test_insert_overwrite() { |
7081 | let mut m = HashMap::new(); |
7082 | assert!(m.insert(1, 2).is_none()); |
7083 | assert_eq!(*m.get(&1).unwrap(), 2); |
7084 | assert!(m.insert(1, 3).is_some()); |
7085 | assert_eq!(*m.get(&1).unwrap(), 3); |
7086 | } |
7087 | |
7088 | #[test] |
7089 | fn test_insert_conflicts() { |
7090 | let mut m = HashMap::with_capacity(4); |
7091 | assert!(m.insert(1, 2).is_none()); |
7092 | assert!(m.insert(5, 3).is_none()); |
7093 | assert!(m.insert(9, 4).is_none()); |
7094 | assert_eq!(*m.get(&9).unwrap(), 4); |
7095 | assert_eq!(*m.get(&5).unwrap(), 3); |
7096 | assert_eq!(*m.get(&1).unwrap(), 2); |
7097 | } |
7098 | |
7099 | #[test] |
7100 | fn test_conflict_remove() { |
7101 | let mut m = HashMap::with_capacity(4); |
7102 | assert!(m.insert(1, 2).is_none()); |
7103 | assert_eq!(*m.get(&1).unwrap(), 2); |
7104 | assert!(m.insert(5, 3).is_none()); |
7105 | assert_eq!(*m.get(&1).unwrap(), 2); |
7106 | assert_eq!(*m.get(&5).unwrap(), 3); |
7107 | assert!(m.insert(9, 4).is_none()); |
7108 | assert_eq!(*m.get(&1).unwrap(), 2); |
7109 | assert_eq!(*m.get(&5).unwrap(), 3); |
7110 | assert_eq!(*m.get(&9).unwrap(), 4); |
7111 | assert!(m.remove(&1).is_some()); |
7112 | assert_eq!(*m.get(&9).unwrap(), 4); |
7113 | assert_eq!(*m.get(&5).unwrap(), 3); |
7114 | } |
7115 | |
7116 | #[test] |
7117 | fn test_insert_unique_unchecked() { |
7118 | let mut map = HashMap::new(); |
7119 | let (k1, v1) = map.insert_unique_unchecked(10, 11); |
7120 | assert_eq!((&10, &mut 11), (k1, v1)); |
7121 | let (k2, v2) = map.insert_unique_unchecked(20, 21); |
7122 | assert_eq!((&20, &mut 21), (k2, v2)); |
7123 | assert_eq!(Some(&11), map.get(&10)); |
7124 | assert_eq!(Some(&21), map.get(&20)); |
7125 | assert_eq!(None, map.get(&30)); |
7126 | } |
7127 | |
7128 | #[test] |
7129 | fn test_is_empty() { |
7130 | let mut m = HashMap::with_capacity(4); |
7131 | assert!(m.insert(1, 2).is_none()); |
7132 | assert!(!m.is_empty()); |
7133 | assert!(m.remove(&1).is_some()); |
7134 | assert!(m.is_empty()); |
7135 | } |
7136 | |
7137 | #[test] |
7138 | fn test_remove() { |
7139 | let mut m = HashMap::new(); |
7140 | m.insert(1, 2); |
7141 | assert_eq!(m.remove(&1), Some(2)); |
7142 | assert_eq!(m.remove(&1), None); |
7143 | } |
7144 | |
7145 | #[test] |
7146 | fn test_remove_entry() { |
7147 | let mut m = HashMap::new(); |
7148 | m.insert(1, 2); |
7149 | assert_eq!(m.remove_entry(&1), Some((1, 2))); |
7150 | assert_eq!(m.remove(&1), None); |
7151 | } |
7152 | |
7153 | #[test] |
7154 | fn test_iterate() { |
7155 | let mut m = HashMap::with_capacity(4); |
7156 | for i in 0..32 { |
7157 | assert!(m.insert(i, i * 2).is_none()); |
7158 | } |
7159 | assert_eq!(m.len(), 32); |
7160 | |
7161 | let mut observed: u32 = 0; |
7162 | |
7163 | for (k, v) in &m { |
7164 | assert_eq!(*v, *k * 2); |
7165 | observed |= 1 << *k; |
7166 | } |
7167 | assert_eq!(observed, 0xFFFF_FFFF); |
7168 | } |
7169 | |
7170 | #[test] |
7171 | fn test_keys() { |
7172 | let vec = vec![(1, 'a' ), (2, 'b' ), (3, 'c' )]; |
7173 | let map: HashMap<_, _> = vec.into_iter().collect(); |
7174 | let keys: Vec<_> = map.keys().copied().collect(); |
7175 | assert_eq!(keys.len(), 3); |
7176 | assert!(keys.contains(&1)); |
7177 | assert!(keys.contains(&2)); |
7178 | assert!(keys.contains(&3)); |
7179 | } |
7180 | |
7181 | #[test] |
7182 | fn test_values() { |
7183 | let vec = vec![(1, 'a' ), (2, 'b' ), (3, 'c' )]; |
7184 | let map: HashMap<_, _> = vec.into_iter().collect(); |
7185 | let values: Vec<_> = map.values().copied().collect(); |
7186 | assert_eq!(values.len(), 3); |
7187 | assert!(values.contains(&'a' )); |
7188 | assert!(values.contains(&'b' )); |
7189 | assert!(values.contains(&'c' )); |
7190 | } |
7191 | |
7192 | #[test] |
7193 | fn test_values_mut() { |
7194 | let vec = vec![(1, 1), (2, 2), (3, 3)]; |
7195 | let mut map: HashMap<_, _> = vec.into_iter().collect(); |
7196 | for value in map.values_mut() { |
7197 | *value *= 2; |
7198 | } |
7199 | let values: Vec<_> = map.values().copied().collect(); |
7200 | assert_eq!(values.len(), 3); |
7201 | assert!(values.contains(&2)); |
7202 | assert!(values.contains(&4)); |
7203 | assert!(values.contains(&6)); |
7204 | } |
7205 | |
7206 | #[test] |
7207 | fn test_into_keys() { |
7208 | let vec = vec![(1, 'a' ), (2, 'b' ), (3, 'c' )]; |
7209 | let map: HashMap<_, _> = vec.into_iter().collect(); |
7210 | let keys: Vec<_> = map.into_keys().collect(); |
7211 | |
7212 | assert_eq!(keys.len(), 3); |
7213 | assert!(keys.contains(&1)); |
7214 | assert!(keys.contains(&2)); |
7215 | assert!(keys.contains(&3)); |
7216 | } |
7217 | |
7218 | #[test] |
7219 | fn test_into_values() { |
7220 | let vec = vec![(1, 'a' ), (2, 'b' ), (3, 'c' )]; |
7221 | let map: HashMap<_, _> = vec.into_iter().collect(); |
7222 | let values: Vec<_> = map.into_values().collect(); |
7223 | |
7224 | assert_eq!(values.len(), 3); |
7225 | assert!(values.contains(&'a' )); |
7226 | assert!(values.contains(&'b' )); |
7227 | assert!(values.contains(&'c' )); |
7228 | } |
7229 | |
7230 | #[test] |
7231 | fn test_find() { |
7232 | let mut m = HashMap::new(); |
7233 | assert!(m.get(&1).is_none()); |
7234 | m.insert(1, 2); |
7235 | match m.get(&1) { |
7236 | None => panic!(), |
7237 | Some(v) => assert_eq!(*v, 2), |
7238 | } |
7239 | } |
7240 | |
7241 | #[test] |
7242 | fn test_eq() { |
7243 | let mut m1 = HashMap::new(); |
7244 | m1.insert(1, 2); |
7245 | m1.insert(2, 3); |
7246 | m1.insert(3, 4); |
7247 | |
7248 | let mut m2 = HashMap::new(); |
7249 | m2.insert(1, 2); |
7250 | m2.insert(2, 3); |
7251 | |
7252 | assert!(m1 != m2); |
7253 | |
7254 | m2.insert(3, 4); |
7255 | |
7256 | assert_eq!(m1, m2); |
7257 | } |
7258 | |
7259 | #[test] |
7260 | fn test_show() { |
7261 | let mut map = HashMap::new(); |
7262 | let empty: HashMap<i32, i32> = HashMap::new(); |
7263 | |
7264 | map.insert(1, 2); |
7265 | map.insert(3, 4); |
7266 | |
7267 | let map_str = format!("{map:?}" ); |
7268 | |
7269 | assert!(map_str == "{1: 2, 3: 4}" || map_str == "{3: 4, 1: 2}" ); |
7270 | assert_eq!(format!("{empty:?}" ), "{}" ); |
7271 | } |
7272 | |
7273 | #[test] |
7274 | fn test_expand() { |
7275 | let mut m = HashMap::new(); |
7276 | |
7277 | assert_eq!(m.len(), 0); |
7278 | assert!(m.is_empty()); |
7279 | |
7280 | let mut i = 0; |
7281 | let old_raw_cap = m.raw_capacity(); |
7282 | while old_raw_cap == m.raw_capacity() { |
7283 | m.insert(i, i); |
7284 | i += 1; |
7285 | } |
7286 | |
7287 | assert_eq!(m.len(), i); |
7288 | assert!(!m.is_empty()); |
7289 | } |
7290 | |
7291 | #[test] |
7292 | fn test_behavior_resize_policy() { |
7293 | let mut m = HashMap::new(); |
7294 | |
7295 | assert_eq!(m.len(), 0); |
7296 | assert_eq!(m.raw_capacity(), 1); |
7297 | assert!(m.is_empty()); |
7298 | |
7299 | m.insert(0, 0); |
7300 | m.remove(&0); |
7301 | assert!(m.is_empty()); |
7302 | let initial_raw_cap = m.raw_capacity(); |
7303 | m.reserve(initial_raw_cap); |
7304 | let raw_cap = m.raw_capacity(); |
7305 | |
7306 | assert_eq!(raw_cap, initial_raw_cap * 2); |
7307 | |
7308 | let mut i = 0; |
7309 | for _ in 0..raw_cap * 3 / 4 { |
7310 | m.insert(i, i); |
7311 | i += 1; |
7312 | } |
7313 | // three quarters full |
7314 | |
7315 | assert_eq!(m.len(), i); |
7316 | assert_eq!(m.raw_capacity(), raw_cap); |
7317 | |
7318 | for _ in 0..raw_cap / 4 { |
7319 | m.insert(i, i); |
7320 | i += 1; |
7321 | } |
7322 | // half full |
7323 | |
7324 | let new_raw_cap = m.raw_capacity(); |
7325 | assert_eq!(new_raw_cap, raw_cap * 2); |
7326 | |
7327 | for _ in 0..raw_cap / 2 - 1 { |
7328 | i -= 1; |
7329 | m.remove(&i); |
7330 | assert_eq!(m.raw_capacity(), new_raw_cap); |
7331 | } |
7332 | // A little more than one quarter full. |
7333 | m.shrink_to_fit(); |
7334 | assert_eq!(m.raw_capacity(), raw_cap); |
7335 | // again, a little more than half full |
7336 | for _ in 0..raw_cap / 2 { |
7337 | i -= 1; |
7338 | m.remove(&i); |
7339 | } |
7340 | m.shrink_to_fit(); |
7341 | |
7342 | assert_eq!(m.len(), i); |
7343 | assert!(!m.is_empty()); |
7344 | assert_eq!(m.raw_capacity(), initial_raw_cap); |
7345 | } |
7346 | |
7347 | #[test] |
7348 | fn test_reserve_shrink_to_fit() { |
7349 | let mut m = HashMap::new(); |
7350 | m.insert(0, 0); |
7351 | m.remove(&0); |
7352 | assert!(m.capacity() >= m.len()); |
7353 | for i in 0..128 { |
7354 | m.insert(i, i); |
7355 | } |
7356 | m.reserve(256); |
7357 | |
7358 | let usable_cap = m.capacity(); |
7359 | for i in 128..(128 + 256) { |
7360 | m.insert(i, i); |
7361 | assert_eq!(m.capacity(), usable_cap); |
7362 | } |
7363 | |
7364 | for i in 100..(128 + 256) { |
7365 | assert_eq!(m.remove(&i), Some(i)); |
7366 | } |
7367 | m.shrink_to_fit(); |
7368 | |
7369 | assert_eq!(m.len(), 100); |
7370 | assert!(!m.is_empty()); |
7371 | assert!(m.capacity() >= m.len()); |
7372 | |
7373 | for i in 0..100 { |
7374 | assert_eq!(m.remove(&i), Some(i)); |
7375 | } |
7376 | m.shrink_to_fit(); |
7377 | m.insert(0, 0); |
7378 | |
7379 | assert_eq!(m.len(), 1); |
7380 | assert!(m.capacity() >= m.len()); |
7381 | assert_eq!(m.remove(&0), Some(0)); |
7382 | } |
7383 | |
7384 | #[test] |
7385 | fn test_from_iter() { |
7386 | let xs = [(1, 1), (2, 2), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)]; |
7387 | |
7388 | let map: HashMap<_, _> = xs.iter().copied().collect(); |
7389 | |
7390 | for &(k, v) in &xs { |
7391 | assert_eq!(map.get(&k), Some(&v)); |
7392 | } |
7393 | |
7394 | assert_eq!(map.iter().len(), xs.len() - 1); |
7395 | } |
7396 | |
7397 | #[test] |
7398 | fn test_size_hint() { |
7399 | let xs = [(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)]; |
7400 | |
7401 | let map: HashMap<_, _> = xs.iter().copied().collect(); |
7402 | |
7403 | let mut iter = map.iter(); |
7404 | |
7405 | for _ in iter.by_ref().take(3) {} |
7406 | |
7407 | assert_eq!(iter.size_hint(), (3, Some(3))); |
7408 | } |
7409 | |
7410 | #[test] |
7411 | fn test_iter_len() { |
7412 | let xs = [(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)]; |
7413 | |
7414 | let map: HashMap<_, _> = xs.iter().copied().collect(); |
7415 | |
7416 | let mut iter = map.iter(); |
7417 | |
7418 | for _ in iter.by_ref().take(3) {} |
7419 | |
7420 | assert_eq!(iter.len(), 3); |
7421 | } |
7422 | |
7423 | #[test] |
7424 | fn test_mut_size_hint() { |
7425 | let xs = [(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)]; |
7426 | |
7427 | let mut map: HashMap<_, _> = xs.iter().copied().collect(); |
7428 | |
7429 | let mut iter = map.iter_mut(); |
7430 | |
7431 | for _ in iter.by_ref().take(3) {} |
7432 | |
7433 | assert_eq!(iter.size_hint(), (3, Some(3))); |
7434 | } |
7435 | |
7436 | #[test] |
7437 | fn test_iter_mut_len() { |
7438 | let xs = [(1, 1), (2, 2), (3, 3), (4, 4), (5, 5), (6, 6)]; |
7439 | |
7440 | let mut map: HashMap<_, _> = xs.iter().copied().collect(); |
7441 | |
7442 | let mut iter = map.iter_mut(); |
7443 | |
7444 | for _ in iter.by_ref().take(3) {} |
7445 | |
7446 | assert_eq!(iter.len(), 3); |
7447 | } |
7448 | |
7449 | #[test] |
7450 | fn test_index() { |
7451 | let mut map = HashMap::new(); |
7452 | |
7453 | map.insert(1, 2); |
7454 | map.insert(2, 1); |
7455 | map.insert(3, 4); |
7456 | |
7457 | assert_eq!(map[&2], 1); |
7458 | } |
7459 | |
7460 | #[test] |
7461 | #[should_panic ] |
7462 | fn test_index_nonexistent() { |
7463 | let mut map = HashMap::new(); |
7464 | |
7465 | map.insert(1, 2); |
7466 | map.insert(2, 1); |
7467 | map.insert(3, 4); |
7468 | |
7469 | #[allow (clippy::no_effect)] // false positive lint |
7470 | map[&4]; |
7471 | } |
7472 | |
7473 | #[test] |
7474 | fn test_entry() { |
7475 | let xs = [(1, 10), (2, 20), (3, 30), (4, 40), (5, 50), (6, 60)]; |
7476 | |
7477 | let mut map: HashMap<_, _> = xs.iter().copied().collect(); |
7478 | |
7479 | // Existing key (insert) |
7480 | match map.entry(1) { |
7481 | Vacant(_) => unreachable!(), |
7482 | Occupied(mut view) => { |
7483 | assert_eq!(view.get(), &10); |
7484 | assert_eq!(view.insert(100), 10); |
7485 | } |
7486 | } |
7487 | assert_eq!(map.get(&1).unwrap(), &100); |
7488 | assert_eq!(map.len(), 6); |
7489 | |
7490 | // Existing key (update) |
7491 | match map.entry(2) { |
7492 | Vacant(_) => unreachable!(), |
7493 | Occupied(mut view) => { |
7494 | let v = view.get_mut(); |
7495 | let new_v = (*v) * 10; |
7496 | *v = new_v; |
7497 | } |
7498 | } |
7499 | assert_eq!(map.get(&2).unwrap(), &200); |
7500 | assert_eq!(map.len(), 6); |
7501 | |
7502 | // Existing key (take) |
7503 | match map.entry(3) { |
7504 | Vacant(_) => unreachable!(), |
7505 | Occupied(view) => { |
7506 | assert_eq!(view.remove(), 30); |
7507 | } |
7508 | } |
7509 | assert_eq!(map.get(&3), None); |
7510 | assert_eq!(map.len(), 5); |
7511 | |
7512 | // Inexistent key (insert) |
7513 | match map.entry(10) { |
7514 | Occupied(_) => unreachable!(), |
7515 | Vacant(view) => { |
7516 | assert_eq!(*view.insert(1000), 1000); |
7517 | } |
7518 | } |
7519 | assert_eq!(map.get(&10).unwrap(), &1000); |
7520 | assert_eq!(map.len(), 6); |
7521 | } |
7522 | |
7523 | #[test] |
7524 | fn test_entry_ref() { |
7525 | let xs = [ |
7526 | ("One" .to_owned(), 10), |
7527 | ("Two" .to_owned(), 20), |
7528 | ("Three" .to_owned(), 30), |
7529 | ("Four" .to_owned(), 40), |
7530 | ("Five" .to_owned(), 50), |
7531 | ("Six" .to_owned(), 60), |
7532 | ]; |
7533 | |
7534 | let mut map: HashMap<_, _> = xs.iter().cloned().collect(); |
7535 | |
7536 | // Existing key (insert) |
7537 | match map.entry_ref("One" ) { |
7538 | EntryRef::Vacant(_) => unreachable!(), |
7539 | EntryRef::Occupied(mut view) => { |
7540 | assert_eq!(view.get(), &10); |
7541 | assert_eq!(view.insert(100), 10); |
7542 | } |
7543 | } |
7544 | assert_eq!(map.get("One" ).unwrap(), &100); |
7545 | assert_eq!(map.len(), 6); |
7546 | |
7547 | // Existing key (update) |
7548 | match map.entry_ref("Two" ) { |
7549 | EntryRef::Vacant(_) => unreachable!(), |
7550 | EntryRef::Occupied(mut view) => { |
7551 | let v = view.get_mut(); |
7552 | let new_v = (*v) * 10; |
7553 | *v = new_v; |
7554 | } |
7555 | } |
7556 | assert_eq!(map.get("Two" ).unwrap(), &200); |
7557 | assert_eq!(map.len(), 6); |
7558 | |
7559 | // Existing key (take) |
7560 | match map.entry_ref("Three" ) { |
7561 | EntryRef::Vacant(_) => unreachable!(), |
7562 | EntryRef::Occupied(view) => { |
7563 | assert_eq!(view.remove(), 30); |
7564 | } |
7565 | } |
7566 | assert_eq!(map.get("Three" ), None); |
7567 | assert_eq!(map.len(), 5); |
7568 | |
7569 | // Inexistent key (insert) |
7570 | match map.entry_ref("Ten" ) { |
7571 | EntryRef::Occupied(_) => unreachable!(), |
7572 | EntryRef::Vacant(view) => { |
7573 | assert_eq!(*view.insert(1000), 1000); |
7574 | } |
7575 | } |
7576 | assert_eq!(map.get("Ten" ).unwrap(), &1000); |
7577 | assert_eq!(map.len(), 6); |
7578 | } |
7579 | |
7580 | #[test] |
7581 | fn test_entry_take_doesnt_corrupt() { |
7582 | #![allow (deprecated)] //rand |
7583 | // Test for #19292 |
7584 | fn check(m: &HashMap<i32, ()>) { |
7585 | for k in m.keys() { |
7586 | assert!(m.contains_key(k), "{k} is in keys() but not in the map?" ); |
7587 | } |
7588 | } |
7589 | |
7590 | let mut m = HashMap::new(); |
7591 | |
7592 | let mut rng = { |
7593 | let seed = u64::from_le_bytes(*b"testseed" ); |
7594 | SmallRng::seed_from_u64(seed) |
7595 | }; |
7596 | |
7597 | // Populate the map with some items. |
7598 | for _ in 0..50 { |
7599 | let x = rng.gen_range(-10..10); |
7600 | m.insert(x, ()); |
7601 | } |
7602 | |
7603 | for _ in 0..1000 { |
7604 | let x = rng.gen_range(-10..10); |
7605 | match m.entry(x) { |
7606 | Vacant(_) => {} |
7607 | Occupied(e) => { |
7608 | e.remove(); |
7609 | } |
7610 | } |
7611 | |
7612 | check(&m); |
7613 | } |
7614 | } |
7615 | |
7616 | #[test] |
7617 | fn test_entry_ref_take_doesnt_corrupt() { |
7618 | #![allow (deprecated)] //rand |
7619 | // Test for #19292 |
7620 | fn check(m: &HashMap<std::string::String, ()>) { |
7621 | for k in m.keys() { |
7622 | assert!(m.contains_key(k), "{k} is in keys() but not in the map?" ); |
7623 | } |
7624 | } |
7625 | |
7626 | let mut m = HashMap::new(); |
7627 | |
7628 | let mut rng = { |
7629 | let seed = u64::from_le_bytes(*b"testseed" ); |
7630 | SmallRng::seed_from_u64(seed) |
7631 | }; |
7632 | |
7633 | // Populate the map with some items. |
7634 | for _ in 0..50 { |
7635 | let mut x = std::string::String::with_capacity(1); |
7636 | x.push(rng.gen_range('a' ..='z' )); |
7637 | m.insert(x, ()); |
7638 | } |
7639 | |
7640 | for _ in 0..1000 { |
7641 | let mut x = std::string::String::with_capacity(1); |
7642 | x.push(rng.gen_range('a' ..='z' )); |
7643 | match m.entry_ref(x.as_str()) { |
7644 | EntryRef::Vacant(_) => {} |
7645 | EntryRef::Occupied(e) => { |
7646 | e.remove(); |
7647 | } |
7648 | } |
7649 | |
7650 | check(&m); |
7651 | } |
7652 | } |
7653 | |
7654 | #[test] |
7655 | fn test_extend_ref_k_ref_v() { |
7656 | let mut a = HashMap::new(); |
7657 | a.insert(1, "one" ); |
7658 | let mut b = HashMap::new(); |
7659 | b.insert(2, "two" ); |
7660 | b.insert(3, "three" ); |
7661 | |
7662 | a.extend(&b); |
7663 | |
7664 | assert_eq!(a.len(), 3); |
7665 | assert_eq!(a[&1], "one" ); |
7666 | assert_eq!(a[&2], "two" ); |
7667 | assert_eq!(a[&3], "three" ); |
7668 | } |
7669 | |
7670 | #[test] |
7671 | #[allow (clippy::needless_borrow)] |
7672 | fn test_extend_ref_kv_tuple() { |
7673 | use std::ops::AddAssign; |
7674 | let mut a = HashMap::new(); |
7675 | a.insert(0, 0); |
7676 | |
7677 | fn create_arr<T: AddAssign<T> + Copy, const N: usize>(start: T, step: T) -> [(T, T); N] { |
7678 | let mut outs: [(T, T); N] = [(start, start); N]; |
7679 | let mut element = step; |
7680 | outs.iter_mut().skip(1).for_each(|(k, v)| { |
7681 | *k += element; |
7682 | *v += element; |
7683 | element += step; |
7684 | }); |
7685 | outs |
7686 | } |
7687 | |
7688 | let for_iter: Vec<_> = (0..100).map(|i| (i, i)).collect(); |
7689 | let iter = for_iter.iter(); |
7690 | let vec: Vec<_> = (100..200).map(|i| (i, i)).collect(); |
7691 | a.extend(iter); |
7692 | a.extend(&vec); |
7693 | a.extend(create_arr::<i32, 100>(200, 1)); |
7694 | |
7695 | assert_eq!(a.len(), 300); |
7696 | |
7697 | for item in 0..300 { |
7698 | assert_eq!(a[&item], item); |
7699 | } |
7700 | } |
7701 | |
7702 | #[test] |
7703 | fn test_capacity_not_less_than_len() { |
7704 | let mut a = HashMap::new(); |
7705 | let mut item = 0; |
7706 | |
7707 | for _ in 0..116 { |
7708 | a.insert(item, 0); |
7709 | item += 1; |
7710 | } |
7711 | |
7712 | assert!(a.capacity() > a.len()); |
7713 | |
7714 | let free = a.capacity() - a.len(); |
7715 | for _ in 0..free { |
7716 | a.insert(item, 0); |
7717 | item += 1; |
7718 | } |
7719 | |
7720 | assert_eq!(a.len(), a.capacity()); |
7721 | |
7722 | // Insert at capacity should cause allocation. |
7723 | a.insert(item, 0); |
7724 | assert!(a.capacity() > a.len()); |
7725 | } |
7726 | |
7727 | #[test] |
7728 | fn test_occupied_entry_key() { |
7729 | let mut a = HashMap::new(); |
7730 | let key = "hello there" ; |
7731 | let value = "value goes here" ; |
7732 | assert!(a.is_empty()); |
7733 | a.insert(key, value); |
7734 | assert_eq!(a.len(), 1); |
7735 | assert_eq!(a[key], value); |
7736 | |
7737 | match a.entry(key) { |
7738 | Vacant(_) => panic!(), |
7739 | Occupied(e) => assert_eq!(key, *e.key()), |
7740 | } |
7741 | assert_eq!(a.len(), 1); |
7742 | assert_eq!(a[key], value); |
7743 | } |
7744 | |
7745 | #[test] |
7746 | fn test_occupied_entry_ref_key() { |
7747 | let mut a = HashMap::new(); |
7748 | let key = "hello there" ; |
7749 | let value = "value goes here" ; |
7750 | assert!(a.is_empty()); |
7751 | a.insert(key.to_owned(), value); |
7752 | assert_eq!(a.len(), 1); |
7753 | assert_eq!(a[key], value); |
7754 | |
7755 | match a.entry_ref(key) { |
7756 | EntryRef::Vacant(_) => panic!(), |
7757 | EntryRef::Occupied(e) => assert_eq!(key, e.key()), |
7758 | } |
7759 | assert_eq!(a.len(), 1); |
7760 | assert_eq!(a[key], value); |
7761 | } |
7762 | |
7763 | #[test] |
7764 | fn test_vacant_entry_key() { |
7765 | let mut a = HashMap::new(); |
7766 | let key = "hello there" ; |
7767 | let value = "value goes here" ; |
7768 | |
7769 | assert!(a.is_empty()); |
7770 | match a.entry(key) { |
7771 | Occupied(_) => panic!(), |
7772 | Vacant(e) => { |
7773 | assert_eq!(key, *e.key()); |
7774 | e.insert(value); |
7775 | } |
7776 | } |
7777 | assert_eq!(a.len(), 1); |
7778 | assert_eq!(a[key], value); |
7779 | } |
7780 | |
7781 | #[test] |
7782 | fn test_vacant_entry_ref_key() { |
7783 | let mut a: HashMap<std::string::String, &str> = HashMap::new(); |
7784 | let key = "hello there" ; |
7785 | let value = "value goes here" ; |
7786 | |
7787 | assert!(a.is_empty()); |
7788 | match a.entry_ref(key) { |
7789 | EntryRef::Occupied(_) => panic!(), |
7790 | EntryRef::Vacant(e) => { |
7791 | assert_eq!(key, e.key()); |
7792 | e.insert(value); |
7793 | } |
7794 | } |
7795 | assert_eq!(a.len(), 1); |
7796 | assert_eq!(a[key], value); |
7797 | } |
7798 | |
7799 | #[test] |
7800 | fn test_occupied_entry_replace_entry_with() { |
7801 | let mut a = HashMap::new(); |
7802 | |
7803 | let key = "a key" ; |
7804 | let value = "an initial value" ; |
7805 | let new_value = "a new value" ; |
7806 | |
7807 | let entry = a.entry(key).insert(value).replace_entry_with(|k, v| { |
7808 | assert_eq!(k, &key); |
7809 | assert_eq!(v, value); |
7810 | Some(new_value) |
7811 | }); |
7812 | |
7813 | match entry { |
7814 | Occupied(e) => { |
7815 | assert_eq!(e.key(), &key); |
7816 | assert_eq!(e.get(), &new_value); |
7817 | } |
7818 | Vacant(_) => panic!(), |
7819 | } |
7820 | |
7821 | assert_eq!(a[key], new_value); |
7822 | assert_eq!(a.len(), 1); |
7823 | |
7824 | let entry = match a.entry(key) { |
7825 | Occupied(e) => e.replace_entry_with(|k, v| { |
7826 | assert_eq!(k, &key); |
7827 | assert_eq!(v, new_value); |
7828 | None |
7829 | }), |
7830 | Vacant(_) => panic!(), |
7831 | }; |
7832 | |
7833 | match entry { |
7834 | Vacant(e) => assert_eq!(e.key(), &key), |
7835 | Occupied(_) => panic!(), |
7836 | } |
7837 | |
7838 | assert!(!a.contains_key(key)); |
7839 | assert_eq!(a.len(), 0); |
7840 | } |
7841 | |
7842 | #[test] |
7843 | fn test_occupied_entry_ref_replace_entry_with() { |
7844 | let mut a: HashMap<std::string::String, &str> = HashMap::new(); |
7845 | |
7846 | let key = "a key" ; |
7847 | let value = "an initial value" ; |
7848 | let new_value = "a new value" ; |
7849 | |
7850 | let entry = a.entry_ref(key).insert(value).replace_entry_with(|k, v| { |
7851 | assert_eq!(k, key); |
7852 | assert_eq!(v, value); |
7853 | Some(new_value) |
7854 | }); |
7855 | |
7856 | match entry { |
7857 | EntryRef::Occupied(e) => { |
7858 | assert_eq!(e.key(), key); |
7859 | assert_eq!(e.get(), &new_value); |
7860 | } |
7861 | EntryRef::Vacant(_) => panic!(), |
7862 | } |
7863 | |
7864 | assert_eq!(a[key], new_value); |
7865 | assert_eq!(a.len(), 1); |
7866 | |
7867 | let entry = match a.entry_ref(key) { |
7868 | EntryRef::Occupied(e) => e.replace_entry_with(|k, v| { |
7869 | assert_eq!(k, key); |
7870 | assert_eq!(v, new_value); |
7871 | None |
7872 | }), |
7873 | EntryRef::Vacant(_) => panic!(), |
7874 | }; |
7875 | |
7876 | match entry { |
7877 | EntryRef::Vacant(e) => assert_eq!(e.key(), key), |
7878 | EntryRef::Occupied(_) => panic!(), |
7879 | } |
7880 | |
7881 | assert!(!a.contains_key(key)); |
7882 | assert_eq!(a.len(), 0); |
7883 | } |
7884 | |
7885 | #[test] |
7886 | fn test_entry_and_replace_entry_with() { |
7887 | let mut a = HashMap::new(); |
7888 | |
7889 | let key = "a key" ; |
7890 | let value = "an initial value" ; |
7891 | let new_value = "a new value" ; |
7892 | |
7893 | let entry = a.entry(key).and_replace_entry_with(|_, _| panic!()); |
7894 | |
7895 | match entry { |
7896 | Vacant(e) => assert_eq!(e.key(), &key), |
7897 | Occupied(_) => panic!(), |
7898 | } |
7899 | |
7900 | a.insert(key, value); |
7901 | |
7902 | let entry = a.entry(key).and_replace_entry_with(|k, v| { |
7903 | assert_eq!(k, &key); |
7904 | assert_eq!(v, value); |
7905 | Some(new_value) |
7906 | }); |
7907 | |
7908 | match entry { |
7909 | Occupied(e) => { |
7910 | assert_eq!(e.key(), &key); |
7911 | assert_eq!(e.get(), &new_value); |
7912 | } |
7913 | Vacant(_) => panic!(), |
7914 | } |
7915 | |
7916 | assert_eq!(a[key], new_value); |
7917 | assert_eq!(a.len(), 1); |
7918 | |
7919 | let entry = a.entry(key).and_replace_entry_with(|k, v| { |
7920 | assert_eq!(k, &key); |
7921 | assert_eq!(v, new_value); |
7922 | None |
7923 | }); |
7924 | |
7925 | match entry { |
7926 | Vacant(e) => assert_eq!(e.key(), &key), |
7927 | Occupied(_) => panic!(), |
7928 | } |
7929 | |
7930 | assert!(!a.contains_key(key)); |
7931 | assert_eq!(a.len(), 0); |
7932 | } |
7933 | |
7934 | #[test] |
7935 | fn test_entry_ref_and_replace_entry_with() { |
7936 | let mut a = HashMap::new(); |
7937 | |
7938 | let key = "a key" ; |
7939 | let value = "an initial value" ; |
7940 | let new_value = "a new value" ; |
7941 | |
7942 | let entry = a.entry_ref(key).and_replace_entry_with(|_, _| panic!()); |
7943 | |
7944 | match entry { |
7945 | EntryRef::Vacant(e) => assert_eq!(e.key(), key), |
7946 | EntryRef::Occupied(_) => panic!(), |
7947 | } |
7948 | |
7949 | a.insert(key.to_owned(), value); |
7950 | |
7951 | let entry = a.entry_ref(key).and_replace_entry_with(|k, v| { |
7952 | assert_eq!(k, key); |
7953 | assert_eq!(v, value); |
7954 | Some(new_value) |
7955 | }); |
7956 | |
7957 | match entry { |
7958 | EntryRef::Occupied(e) => { |
7959 | assert_eq!(e.key(), key); |
7960 | assert_eq!(e.get(), &new_value); |
7961 | } |
7962 | EntryRef::Vacant(_) => panic!(), |
7963 | } |
7964 | |
7965 | assert_eq!(a[key], new_value); |
7966 | assert_eq!(a.len(), 1); |
7967 | |
7968 | let entry = a.entry_ref(key).and_replace_entry_with(|k, v| { |
7969 | assert_eq!(k, key); |
7970 | assert_eq!(v, new_value); |
7971 | None |
7972 | }); |
7973 | |
7974 | match entry { |
7975 | EntryRef::Vacant(e) => assert_eq!(e.key(), key), |
7976 | EntryRef::Occupied(_) => panic!(), |
7977 | } |
7978 | |
7979 | assert!(!a.contains_key(key)); |
7980 | assert_eq!(a.len(), 0); |
7981 | } |
7982 | |
7983 | #[test] |
7984 | fn test_raw_occupied_entry_replace_entry_with() { |
7985 | let mut a = HashMap::new(); |
7986 | |
7987 | let key = "a key" ; |
7988 | let value = "an initial value" ; |
7989 | let new_value = "a new value" ; |
7990 | |
7991 | let entry = a |
7992 | .raw_entry_mut() |
7993 | .from_key(&key) |
7994 | .insert(key, value) |
7995 | .replace_entry_with(|k, v| { |
7996 | assert_eq!(k, &key); |
7997 | assert_eq!(v, value); |
7998 | Some(new_value) |
7999 | }); |
8000 | |
8001 | match entry { |
8002 | RawEntryMut::Occupied(e) => { |
8003 | assert_eq!(e.key(), &key); |
8004 | assert_eq!(e.get(), &new_value); |
8005 | } |
8006 | RawEntryMut::Vacant(_) => panic!(), |
8007 | } |
8008 | |
8009 | assert_eq!(a[key], new_value); |
8010 | assert_eq!(a.len(), 1); |
8011 | |
8012 | let entry = match a.raw_entry_mut().from_key(&key) { |
8013 | RawEntryMut::Occupied(e) => e.replace_entry_with(|k, v| { |
8014 | assert_eq!(k, &key); |
8015 | assert_eq!(v, new_value); |
8016 | None |
8017 | }), |
8018 | RawEntryMut::Vacant(_) => panic!(), |
8019 | }; |
8020 | |
8021 | match entry { |
8022 | RawEntryMut::Vacant(_) => {} |
8023 | RawEntryMut::Occupied(_) => panic!(), |
8024 | } |
8025 | |
8026 | assert!(!a.contains_key(key)); |
8027 | assert_eq!(a.len(), 0); |
8028 | } |
8029 | |
8030 | #[test] |
8031 | fn test_raw_entry_and_replace_entry_with() { |
8032 | let mut a = HashMap::new(); |
8033 | |
8034 | let key = "a key" ; |
8035 | let value = "an initial value" ; |
8036 | let new_value = "a new value" ; |
8037 | |
8038 | let entry = a |
8039 | .raw_entry_mut() |
8040 | .from_key(&key) |
8041 | .and_replace_entry_with(|_, _| panic!()); |
8042 | |
8043 | match entry { |
8044 | RawEntryMut::Vacant(_) => {} |
8045 | RawEntryMut::Occupied(_) => panic!(), |
8046 | } |
8047 | |
8048 | a.insert(key, value); |
8049 | |
8050 | let entry = a |
8051 | .raw_entry_mut() |
8052 | .from_key(&key) |
8053 | .and_replace_entry_with(|k, v| { |
8054 | assert_eq!(k, &key); |
8055 | assert_eq!(v, value); |
8056 | Some(new_value) |
8057 | }); |
8058 | |
8059 | match entry { |
8060 | RawEntryMut::Occupied(e) => { |
8061 | assert_eq!(e.key(), &key); |
8062 | assert_eq!(e.get(), &new_value); |
8063 | } |
8064 | RawEntryMut::Vacant(_) => panic!(), |
8065 | } |
8066 | |
8067 | assert_eq!(a[key], new_value); |
8068 | assert_eq!(a.len(), 1); |
8069 | |
8070 | let entry = a |
8071 | .raw_entry_mut() |
8072 | .from_key(&key) |
8073 | .and_replace_entry_with(|k, v| { |
8074 | assert_eq!(k, &key); |
8075 | assert_eq!(v, new_value); |
8076 | None |
8077 | }); |
8078 | |
8079 | match entry { |
8080 | RawEntryMut::Vacant(_) => {} |
8081 | RawEntryMut::Occupied(_) => panic!(), |
8082 | } |
8083 | |
8084 | assert!(!a.contains_key(key)); |
8085 | assert_eq!(a.len(), 0); |
8086 | } |
8087 | |
8088 | #[test] |
8089 | fn test_replace_entry_with_doesnt_corrupt() { |
8090 | #![allow (deprecated)] //rand |
8091 | // Test for #19292 |
8092 | fn check(m: &HashMap<i32, ()>) { |
8093 | for k in m.keys() { |
8094 | assert!(m.contains_key(k), "{k} is in keys() but not in the map?" ); |
8095 | } |
8096 | } |
8097 | |
8098 | let mut m = HashMap::new(); |
8099 | |
8100 | let mut rng = { |
8101 | let seed = u64::from_le_bytes(*b"testseed" ); |
8102 | SmallRng::seed_from_u64(seed) |
8103 | }; |
8104 | |
8105 | // Populate the map with some items. |
8106 | for _ in 0..50 { |
8107 | let x = rng.gen_range(-10..10); |
8108 | m.insert(x, ()); |
8109 | } |
8110 | |
8111 | for _ in 0..1000 { |
8112 | let x = rng.gen_range(-10..10); |
8113 | m.entry(x).and_replace_entry_with(|_, _| None); |
8114 | check(&m); |
8115 | } |
8116 | } |
8117 | |
8118 | #[test] |
8119 | fn test_replace_entry_ref_with_doesnt_corrupt() { |
8120 | #![allow (deprecated)] //rand |
8121 | // Test for #19292 |
8122 | fn check(m: &HashMap<std::string::String, ()>) { |
8123 | for k in m.keys() { |
8124 | assert!(m.contains_key(k), "{k} is in keys() but not in the map?" ); |
8125 | } |
8126 | } |
8127 | |
8128 | let mut m = HashMap::new(); |
8129 | |
8130 | let mut rng = { |
8131 | let seed = u64::from_le_bytes(*b"testseed" ); |
8132 | SmallRng::seed_from_u64(seed) |
8133 | }; |
8134 | |
8135 | // Populate the map with some items. |
8136 | for _ in 0..50 { |
8137 | let mut x = std::string::String::with_capacity(1); |
8138 | x.push(rng.gen_range('a' ..='z' )); |
8139 | m.insert(x, ()); |
8140 | } |
8141 | |
8142 | for _ in 0..1000 { |
8143 | let mut x = std::string::String::with_capacity(1); |
8144 | x.push(rng.gen_range('a' ..='z' )); |
8145 | m.entry_ref(x.as_str()).and_replace_entry_with(|_, _| None); |
8146 | check(&m); |
8147 | } |
8148 | } |
8149 | |
8150 | #[test] |
8151 | fn test_retain() { |
8152 | let mut map: HashMap<i32, i32> = (0..100).map(|x| (x, x * 10)).collect(); |
8153 | |
8154 | map.retain(|&k, _| k % 2 == 0); |
8155 | assert_eq!(map.len(), 50); |
8156 | assert_eq!(map[&2], 20); |
8157 | assert_eq!(map[&4], 40); |
8158 | assert_eq!(map[&6], 60); |
8159 | } |
8160 | |
8161 | #[test] |
8162 | fn test_extract_if() { |
8163 | { |
8164 | let mut map: HashMap<i32, i32> = (0..8).map(|x| (x, x * 10)).collect(); |
8165 | let drained = map.extract_if(|&k, _| k % 2 == 0); |
8166 | let mut out = drained.collect::<Vec<_>>(); |
8167 | out.sort_unstable(); |
8168 | assert_eq!(vec![(0, 0), (2, 20), (4, 40), (6, 60)], out); |
8169 | assert_eq!(map.len(), 4); |
8170 | } |
8171 | { |
8172 | let mut map: HashMap<i32, i32> = (0..8).map(|x| (x, x * 10)).collect(); |
8173 | map.extract_if(|&k, _| k % 2 == 0).for_each(drop); |
8174 | assert_eq!(map.len(), 4); |
8175 | } |
8176 | } |
8177 | |
8178 | #[test] |
8179 | #[cfg_attr (miri, ignore)] // FIXME: no OOM signalling (https://github.com/rust-lang/miri/issues/613) |
8180 | fn test_try_reserve() { |
8181 | use crate::TryReserveError::{AllocError, CapacityOverflow}; |
8182 | |
8183 | const MAX_ISIZE: usize = isize::MAX as usize; |
8184 | |
8185 | let mut empty_bytes: HashMap<u8, u8> = HashMap::new(); |
8186 | |
8187 | if let Err(CapacityOverflow) = empty_bytes.try_reserve(usize::MAX) { |
8188 | } else { |
8189 | panic!("usize::MAX should trigger an overflow!" ); |
8190 | } |
8191 | |
8192 | if let Err(CapacityOverflow) = empty_bytes.try_reserve(MAX_ISIZE) { |
8193 | } else { |
8194 | panic!("isize::MAX should trigger an overflow!" ); |
8195 | } |
8196 | |
8197 | if let Err(AllocError { .. }) = empty_bytes.try_reserve(MAX_ISIZE / 5) { |
8198 | } else { |
8199 | // This may succeed if there is enough free memory. Attempt to |
8200 | // allocate a few more hashmaps to ensure the allocation will fail. |
8201 | let mut empty_bytes2: HashMap<u8, u8> = HashMap::new(); |
8202 | let _ = empty_bytes2.try_reserve(MAX_ISIZE / 5); |
8203 | let mut empty_bytes3: HashMap<u8, u8> = HashMap::new(); |
8204 | let _ = empty_bytes3.try_reserve(MAX_ISIZE / 5); |
8205 | let mut empty_bytes4: HashMap<u8, u8> = HashMap::new(); |
8206 | if let Err(AllocError { .. }) = empty_bytes4.try_reserve(MAX_ISIZE / 5) { |
8207 | } else { |
8208 | panic!("isize::MAX / 5 should trigger an OOM!" ); |
8209 | } |
8210 | } |
8211 | } |
8212 | |
8213 | #[test] |
8214 | fn test_raw_entry() { |
8215 | use super::RawEntryMut::{Occupied, Vacant}; |
8216 | |
8217 | let xs = [(1_i32, 10_i32), (2, 20), (3, 30), (4, 40), (5, 50), (6, 60)]; |
8218 | |
8219 | let mut map: HashMap<_, _> = xs.iter().copied().collect(); |
8220 | |
8221 | let compute_hash = |map: &HashMap<i32, i32>, k: i32| -> u64 { |
8222 | super::make_hash::<i32, _>(map.hasher(), &k) |
8223 | }; |
8224 | |
8225 | // Existing key (insert) |
8226 | match map.raw_entry_mut().from_key(&1) { |
8227 | Vacant(_) => unreachable!(), |
8228 | Occupied(mut view) => { |
8229 | assert_eq!(view.get(), &10); |
8230 | assert_eq!(view.insert(100), 10); |
8231 | } |
8232 | } |
8233 | let hash1 = compute_hash(&map, 1); |
8234 | assert_eq!(map.raw_entry().from_key(&1).unwrap(), (&1, &100)); |
8235 | assert_eq!( |
8236 | map.raw_entry().from_hash(hash1, |k| *k == 1).unwrap(), |
8237 | (&1, &100) |
8238 | ); |
8239 | assert_eq!( |
8240 | map.raw_entry().from_key_hashed_nocheck(hash1, &1).unwrap(), |
8241 | (&1, &100) |
8242 | ); |
8243 | assert_eq!(map.len(), 6); |
8244 | |
8245 | // Existing key (update) |
8246 | match map.raw_entry_mut().from_key(&2) { |
8247 | Vacant(_) => unreachable!(), |
8248 | Occupied(mut view) => { |
8249 | let v = view.get_mut(); |
8250 | let new_v = (*v) * 10; |
8251 | *v = new_v; |
8252 | } |
8253 | } |
8254 | let hash2 = compute_hash(&map, 2); |
8255 | assert_eq!(map.raw_entry().from_key(&2).unwrap(), (&2, &200)); |
8256 | assert_eq!( |
8257 | map.raw_entry().from_hash(hash2, |k| *k == 2).unwrap(), |
8258 | (&2, &200) |
8259 | ); |
8260 | assert_eq!( |
8261 | map.raw_entry().from_key_hashed_nocheck(hash2, &2).unwrap(), |
8262 | (&2, &200) |
8263 | ); |
8264 | assert_eq!(map.len(), 6); |
8265 | |
8266 | // Existing key (take) |
8267 | let hash3 = compute_hash(&map, 3); |
8268 | match map.raw_entry_mut().from_key_hashed_nocheck(hash3, &3) { |
8269 | Vacant(_) => unreachable!(), |
8270 | Occupied(view) => { |
8271 | assert_eq!(view.remove_entry(), (3, 30)); |
8272 | } |
8273 | } |
8274 | assert_eq!(map.raw_entry().from_key(&3), None); |
8275 | assert_eq!(map.raw_entry().from_hash(hash3, |k| *k == 3), None); |
8276 | assert_eq!(map.raw_entry().from_key_hashed_nocheck(hash3, &3), None); |
8277 | assert_eq!(map.len(), 5); |
8278 | |
8279 | // Nonexistent key (insert) |
8280 | match map.raw_entry_mut().from_key(&10) { |
8281 | Occupied(_) => unreachable!(), |
8282 | Vacant(view) => { |
8283 | assert_eq!(view.insert(10, 1000), (&mut 10, &mut 1000)); |
8284 | } |
8285 | } |
8286 | assert_eq!(map.raw_entry().from_key(&10).unwrap(), (&10, &1000)); |
8287 | assert_eq!(map.len(), 6); |
8288 | |
8289 | // Ensure all lookup methods produce equivalent results. |
8290 | for k in 0..12 { |
8291 | let hash = compute_hash(&map, k); |
8292 | let v = map.get(&k).copied(); |
8293 | let kv = v.as_ref().map(|v| (&k, v)); |
8294 | |
8295 | assert_eq!(map.raw_entry().from_key(&k), kv); |
8296 | assert_eq!(map.raw_entry().from_hash(hash, |q| *q == k), kv); |
8297 | assert_eq!(map.raw_entry().from_key_hashed_nocheck(hash, &k), kv); |
8298 | |
8299 | match map.raw_entry_mut().from_key(&k) { |
8300 | Occupied(o) => assert_eq!(Some(o.get_key_value()), kv), |
8301 | Vacant(_) => assert_eq!(v, None), |
8302 | } |
8303 | match map.raw_entry_mut().from_key_hashed_nocheck(hash, &k) { |
8304 | Occupied(o) => assert_eq!(Some(o.get_key_value()), kv), |
8305 | Vacant(_) => assert_eq!(v, None), |
8306 | } |
8307 | match map.raw_entry_mut().from_hash(hash, |q| *q == k) { |
8308 | Occupied(o) => assert_eq!(Some(o.get_key_value()), kv), |
8309 | Vacant(_) => assert_eq!(v, None), |
8310 | } |
8311 | } |
8312 | } |
8313 | |
8314 | #[test] |
8315 | fn test_key_without_hash_impl() { |
8316 | #[derive(Debug)] |
8317 | struct IntWrapper(u64); |
8318 | |
8319 | let mut m: HashMap<IntWrapper, (), ()> = HashMap::default(); |
8320 | { |
8321 | assert!(m.raw_entry().from_hash(0, |k| k.0 == 0).is_none()); |
8322 | } |
8323 | { |
8324 | let vacant_entry = match m.raw_entry_mut().from_hash(0, |k| k.0 == 0) { |
8325 | RawEntryMut::Occupied(..) => panic!("Found entry for key 0" ), |
8326 | RawEntryMut::Vacant(e) => e, |
8327 | }; |
8328 | vacant_entry.insert_with_hasher(0, IntWrapper(0), (), |k| k.0); |
8329 | } |
8330 | { |
8331 | assert!(m.raw_entry().from_hash(0, |k| k.0 == 0).is_some()); |
8332 | assert!(m.raw_entry().from_hash(1, |k| k.0 == 1).is_none()); |
8333 | assert!(m.raw_entry().from_hash(2, |k| k.0 == 2).is_none()); |
8334 | } |
8335 | { |
8336 | let vacant_entry = match m.raw_entry_mut().from_hash(1, |k| k.0 == 1) { |
8337 | RawEntryMut::Occupied(..) => panic!("Found entry for key 1" ), |
8338 | RawEntryMut::Vacant(e) => e, |
8339 | }; |
8340 | vacant_entry.insert_with_hasher(1, IntWrapper(1), (), |k| k.0); |
8341 | } |
8342 | { |
8343 | assert!(m.raw_entry().from_hash(0, |k| k.0 == 0).is_some()); |
8344 | assert!(m.raw_entry().from_hash(1, |k| k.0 == 1).is_some()); |
8345 | assert!(m.raw_entry().from_hash(2, |k| k.0 == 2).is_none()); |
8346 | } |
8347 | { |
8348 | let occupied_entry = match m.raw_entry_mut().from_hash(0, |k| k.0 == 0) { |
8349 | RawEntryMut::Occupied(e) => e, |
8350 | RawEntryMut::Vacant(..) => panic!("Couldn't find entry for key 0" ), |
8351 | }; |
8352 | occupied_entry.remove(); |
8353 | } |
8354 | assert!(m.raw_entry().from_hash(0, |k| k.0 == 0).is_none()); |
8355 | assert!(m.raw_entry().from_hash(1, |k| k.0 == 1).is_some()); |
8356 | assert!(m.raw_entry().from_hash(2, |k| k.0 == 2).is_none()); |
8357 | } |
8358 | |
8359 | #[test] |
8360 | #[cfg (feature = "raw" )] |
8361 | fn test_into_iter_refresh() { |
8362 | #[cfg (miri)] |
8363 | const N: usize = 32; |
8364 | #[cfg (not(miri))] |
8365 | const N: usize = 128; |
8366 | |
8367 | let mut rng = rand::thread_rng(); |
8368 | for n in 0..N { |
8369 | let mut map = HashMap::new(); |
8370 | for i in 0..n { |
8371 | assert!(map.insert(i, 2 * i).is_none()); |
8372 | } |
8373 | let hash_builder = map.hasher().clone(); |
8374 | |
8375 | let mut it = unsafe { map.table.iter() }; |
8376 | assert_eq!(it.len(), n); |
8377 | |
8378 | let mut i = 0; |
8379 | let mut left = n; |
8380 | let mut removed = Vec::new(); |
8381 | loop { |
8382 | // occasionally remove some elements |
8383 | if i < n && rng.gen_bool(0.1) { |
8384 | let hash_value = super::make_hash(&hash_builder, &i); |
8385 | |
8386 | unsafe { |
8387 | let e = map.table.find(hash_value, |q| q.0.eq(&i)); |
8388 | if let Some(e) = e { |
8389 | it.reflect_remove(&e); |
8390 | let t = map.table.remove(e).0; |
8391 | removed.push(t); |
8392 | left -= 1; |
8393 | } else { |
8394 | assert!(removed.contains(&(i, 2 * i)), "{i} not in {removed:?}" ); |
8395 | let e = map.table.insert( |
8396 | hash_value, |
8397 | (i, 2 * i), |
8398 | super::make_hasher::<_, usize, _>(&hash_builder), |
8399 | ); |
8400 | it.reflect_insert(&e); |
8401 | if let Some(p) = removed.iter().position(|e| e == &(i, 2 * i)) { |
8402 | removed.swap_remove(p); |
8403 | } |
8404 | left += 1; |
8405 | } |
8406 | } |
8407 | } |
8408 | |
8409 | let e = it.next(); |
8410 | if e.is_none() { |
8411 | break; |
8412 | } |
8413 | assert!(i < n); |
8414 | let t = unsafe { e.unwrap().as_ref() }; |
8415 | assert!(!removed.contains(t)); |
8416 | let (key, value) = t; |
8417 | assert_eq!(*value, 2 * key); |
8418 | i += 1; |
8419 | } |
8420 | assert!(i <= n); |
8421 | |
8422 | // just for safety: |
8423 | assert_eq!(map.table.len(), left); |
8424 | } |
8425 | } |
8426 | |
8427 | #[test] |
8428 | fn test_const_with_hasher() { |
8429 | use core::hash::BuildHasher; |
8430 | use std::collections::hash_map::DefaultHasher; |
8431 | |
8432 | #[derive(Clone)] |
8433 | struct MyHasher; |
8434 | impl BuildHasher for MyHasher { |
8435 | type Hasher = DefaultHasher; |
8436 | |
8437 | fn build_hasher(&self) -> DefaultHasher { |
8438 | DefaultHasher::new() |
8439 | } |
8440 | } |
8441 | |
8442 | const EMPTY_MAP: HashMap<u32, std::string::String, MyHasher> = |
8443 | HashMap::with_hasher(MyHasher); |
8444 | |
8445 | let mut map = EMPTY_MAP; |
8446 | map.insert(17, "seventeen" .to_owned()); |
8447 | assert_eq!("seventeen" , map[&17]); |
8448 | } |
8449 | |
8450 | #[test] |
8451 | fn test_get_each_mut() { |
8452 | let mut map = HashMap::new(); |
8453 | map.insert("foo" .to_owned(), 0); |
8454 | map.insert("bar" .to_owned(), 10); |
8455 | map.insert("baz" .to_owned(), 20); |
8456 | map.insert("qux" .to_owned(), 30); |
8457 | |
8458 | let xs = map.get_many_mut(["foo" , "qux" ]); |
8459 | assert_eq!(xs, Some([&mut 0, &mut 30])); |
8460 | |
8461 | let xs = map.get_many_mut(["foo" , "dud" ]); |
8462 | assert_eq!(xs, None); |
8463 | |
8464 | let xs = map.get_many_mut(["foo" , "foo" ]); |
8465 | assert_eq!(xs, None); |
8466 | |
8467 | let ys = map.get_many_key_value_mut(["bar" , "baz" ]); |
8468 | assert_eq!( |
8469 | ys, |
8470 | Some([(&"bar" .to_owned(), &mut 10), (&"baz" .to_owned(), &mut 20),]), |
8471 | ); |
8472 | |
8473 | let ys = map.get_many_key_value_mut(["bar" , "dip" ]); |
8474 | assert_eq!(ys, None); |
8475 | |
8476 | let ys = map.get_many_key_value_mut(["baz" , "baz" ]); |
8477 | assert_eq!(ys, None); |
8478 | } |
8479 | |
8480 | #[test] |
8481 | #[should_panic = "panic in drop" ] |
8482 | fn test_clone_from_double_drop() { |
8483 | #[derive(Clone)] |
8484 | struct CheckedDrop { |
8485 | panic_in_drop: bool, |
8486 | dropped: bool, |
8487 | } |
8488 | impl Drop for CheckedDrop { |
8489 | fn drop(&mut self) { |
8490 | if self.panic_in_drop { |
8491 | self.dropped = true; |
8492 | panic!("panic in drop" ); |
8493 | } |
8494 | if self.dropped { |
8495 | panic!("double drop" ); |
8496 | } |
8497 | self.dropped = true; |
8498 | } |
8499 | } |
8500 | const DISARMED: CheckedDrop = CheckedDrop { |
8501 | panic_in_drop: false, |
8502 | dropped: false, |
8503 | }; |
8504 | const ARMED: CheckedDrop = CheckedDrop { |
8505 | panic_in_drop: true, |
8506 | dropped: false, |
8507 | }; |
8508 | |
8509 | let mut map1 = HashMap::new(); |
8510 | map1.insert(1, DISARMED); |
8511 | map1.insert(2, DISARMED); |
8512 | map1.insert(3, DISARMED); |
8513 | map1.insert(4, DISARMED); |
8514 | |
8515 | let mut map2 = HashMap::new(); |
8516 | map2.insert(1, DISARMED); |
8517 | map2.insert(2, ARMED); |
8518 | map2.insert(3, DISARMED); |
8519 | map2.insert(4, DISARMED); |
8520 | |
8521 | map2.clone_from(&map1); |
8522 | } |
8523 | |
8524 | #[test] |
8525 | #[should_panic = "panic in clone" ] |
8526 | fn test_clone_from_memory_leaks() { |
8527 | use ::alloc::vec::Vec; |
8528 | |
8529 | struct CheckedClone { |
8530 | panic_in_clone: bool, |
8531 | need_drop: Vec<i32>, |
8532 | } |
8533 | impl Clone for CheckedClone { |
8534 | fn clone(&self) -> Self { |
8535 | if self.panic_in_clone { |
8536 | panic!("panic in clone" ) |
8537 | } |
8538 | Self { |
8539 | panic_in_clone: self.panic_in_clone, |
8540 | need_drop: self.need_drop.clone(), |
8541 | } |
8542 | } |
8543 | } |
8544 | let mut map1 = HashMap::new(); |
8545 | map1.insert( |
8546 | 1, |
8547 | CheckedClone { |
8548 | panic_in_clone: false, |
8549 | need_drop: vec![0, 1, 2], |
8550 | }, |
8551 | ); |
8552 | map1.insert( |
8553 | 2, |
8554 | CheckedClone { |
8555 | panic_in_clone: false, |
8556 | need_drop: vec![3, 4, 5], |
8557 | }, |
8558 | ); |
8559 | map1.insert( |
8560 | 3, |
8561 | CheckedClone { |
8562 | panic_in_clone: true, |
8563 | need_drop: vec![6, 7, 8], |
8564 | }, |
8565 | ); |
8566 | let _map2 = map1.clone(); |
8567 | } |
8568 | |
8569 | struct MyAllocInner { |
8570 | drop_count: Arc<AtomicI8>, |
8571 | } |
8572 | |
8573 | #[derive(Clone)] |
8574 | struct MyAlloc { |
8575 | _inner: Arc<MyAllocInner>, |
8576 | } |
8577 | |
8578 | impl MyAlloc { |
8579 | fn new(drop_count: Arc<AtomicI8>) -> Self { |
8580 | MyAlloc { |
8581 | _inner: Arc::new(MyAllocInner { drop_count }), |
8582 | } |
8583 | } |
8584 | } |
8585 | |
8586 | impl Drop for MyAllocInner { |
8587 | fn drop(&mut self) { |
8588 | println!("MyAlloc freed." ); |
8589 | self.drop_count.fetch_sub(1, Ordering::SeqCst); |
8590 | } |
8591 | } |
8592 | |
8593 | unsafe impl Allocator for MyAlloc { |
8594 | fn allocate(&self, layout: Layout) -> std::result::Result<NonNull<[u8]>, AllocError> { |
8595 | let g = Global; |
8596 | g.allocate(layout) |
8597 | } |
8598 | |
8599 | unsafe fn deallocate(&self, ptr: NonNull<u8>, layout: Layout) { |
8600 | let g = Global; |
8601 | g.deallocate(ptr, layout) |
8602 | } |
8603 | } |
8604 | |
8605 | #[test] |
8606 | fn test_hashmap_into_iter_bug() { |
8607 | let dropped: Arc<AtomicI8> = Arc::new(AtomicI8::new(1)); |
8608 | |
8609 | { |
8610 | let mut map = HashMap::with_capacity_in(10, MyAlloc::new(dropped.clone())); |
8611 | for i in 0..10 { |
8612 | map.entry(i).or_insert_with(|| "i" .to_string()); |
8613 | } |
8614 | |
8615 | for (k, v) in map { |
8616 | println!("{}, {}" , k, v); |
8617 | } |
8618 | } |
8619 | |
8620 | // All allocator clones should already be dropped. |
8621 | assert_eq!(dropped.load(Ordering::SeqCst), 0); |
8622 | } |
8623 | |
8624 | #[derive(Debug)] |
8625 | struct CheckedCloneDrop<T> { |
8626 | panic_in_clone: bool, |
8627 | panic_in_drop: bool, |
8628 | dropped: bool, |
8629 | data: T, |
8630 | } |
8631 | |
8632 | impl<T> CheckedCloneDrop<T> { |
8633 | fn new(panic_in_clone: bool, panic_in_drop: bool, data: T) -> Self { |
8634 | CheckedCloneDrop { |
8635 | panic_in_clone, |
8636 | panic_in_drop, |
8637 | dropped: false, |
8638 | data, |
8639 | } |
8640 | } |
8641 | } |
8642 | |
8643 | impl<T: Clone> Clone for CheckedCloneDrop<T> { |
8644 | fn clone(&self) -> Self { |
8645 | if self.panic_in_clone { |
8646 | panic!("panic in clone" ) |
8647 | } |
8648 | Self { |
8649 | panic_in_clone: self.panic_in_clone, |
8650 | panic_in_drop: self.panic_in_drop, |
8651 | dropped: self.dropped, |
8652 | data: self.data.clone(), |
8653 | } |
8654 | } |
8655 | } |
8656 | |
8657 | impl<T> Drop for CheckedCloneDrop<T> { |
8658 | fn drop(&mut self) { |
8659 | if self.panic_in_drop { |
8660 | self.dropped = true; |
8661 | panic!("panic in drop" ); |
8662 | } |
8663 | if self.dropped { |
8664 | panic!("double drop" ); |
8665 | } |
8666 | self.dropped = true; |
8667 | } |
8668 | } |
8669 | |
8670 | /// Return hashmap with predefined distribution of elements. |
8671 | /// All elements will be located in the same order as elements |
8672 | /// returned by iterator. |
8673 | /// |
8674 | /// This function does not panic, but returns an error as a `String` |
8675 | /// to distinguish between a test panic and an error in the input data. |
8676 | fn get_test_map<I, T, A>( |
8677 | iter: I, |
8678 | mut fun: impl FnMut(u64) -> T, |
8679 | alloc: A, |
8680 | ) -> Result<HashMap<u64, CheckedCloneDrop<T>, DefaultHashBuilder, A>, String> |
8681 | where |
8682 | I: Iterator<Item = (bool, bool)> + Clone + ExactSizeIterator, |
8683 | A: Allocator, |
8684 | T: PartialEq + core::fmt::Debug, |
8685 | { |
8686 | use crate::scopeguard::guard; |
8687 | |
8688 | let mut map: HashMap<u64, CheckedCloneDrop<T>, _, A> = |
8689 | HashMap::with_capacity_in(iter.size_hint().0, alloc); |
8690 | { |
8691 | let mut guard = guard(&mut map, |map| { |
8692 | for (_, value) in map.iter_mut() { |
8693 | value.panic_in_drop = false |
8694 | } |
8695 | }); |
8696 | |
8697 | let mut count = 0; |
8698 | // Hash and Key must be equal to each other for controlling the elements placement. |
8699 | for (panic_in_clone, panic_in_drop) in iter.clone() { |
8700 | if core::mem::needs_drop::<T>() && panic_in_drop { |
8701 | return Err(String::from( |
8702 | "panic_in_drop can be set with a type that doesn't need to be dropped" , |
8703 | )); |
8704 | } |
8705 | guard.table.insert( |
8706 | count, |
8707 | ( |
8708 | count, |
8709 | CheckedCloneDrop::new(panic_in_clone, panic_in_drop, fun(count)), |
8710 | ), |
8711 | |(k, _)| *k, |
8712 | ); |
8713 | count += 1; |
8714 | } |
8715 | |
8716 | // Let's check that all elements are located as we wanted |
8717 | let mut check_count = 0; |
8718 | for ((key, value), (panic_in_clone, panic_in_drop)) in guard.iter().zip(iter) { |
8719 | if *key != check_count { |
8720 | return Err(format!( |
8721 | "key != check_count, \nkey: `{}`, \ncheck_count: `{}`" , |
8722 | key, check_count |
8723 | )); |
8724 | } |
8725 | if value.dropped |
8726 | || value.panic_in_clone != panic_in_clone |
8727 | || value.panic_in_drop != panic_in_drop |
8728 | || value.data != fun(check_count) |
8729 | { |
8730 | return Err(format!( |
8731 | "Value is not equal to expected, \nvalue: `{:?}`, \nexpected: \ |
8732 | `CheckedCloneDrop {{ panic_in_clone: {}, panic_in_drop: {}, dropped: {}, data: {:?} }}`" , |
8733 | value, panic_in_clone, panic_in_drop, false, fun(check_count) |
8734 | )); |
8735 | } |
8736 | check_count += 1; |
8737 | } |
8738 | |
8739 | if guard.len() != check_count as usize { |
8740 | return Err(format!( |
8741 | "map.len() != check_count, \nmap.len(): `{}`, \ncheck_count: `{}`" , |
8742 | guard.len(), |
8743 | check_count |
8744 | )); |
8745 | } |
8746 | |
8747 | if count != check_count { |
8748 | return Err(format!( |
8749 | "count != check_count, \ncount: `{}`, \ncheck_count: `{}`" , |
8750 | count, check_count |
8751 | )); |
8752 | } |
8753 | core::mem::forget(guard); |
8754 | } |
8755 | Ok(map) |
8756 | } |
8757 | |
8758 | const DISARMED: bool = false; |
8759 | const ARMED: bool = true; |
8760 | |
8761 | const ARMED_FLAGS: [bool; 8] = [ |
8762 | DISARMED, DISARMED, DISARMED, ARMED, DISARMED, DISARMED, DISARMED, DISARMED, |
8763 | ]; |
8764 | |
8765 | const DISARMED_FLAGS: [bool; 8] = [ |
8766 | DISARMED, DISARMED, DISARMED, DISARMED, DISARMED, DISARMED, DISARMED, DISARMED, |
8767 | ]; |
8768 | |
8769 | #[test] |
8770 | #[should_panic = "panic in clone" ] |
8771 | fn test_clone_memory_leaks_and_double_drop_one() { |
8772 | let dropped: Arc<AtomicI8> = Arc::new(AtomicI8::new(2)); |
8773 | |
8774 | { |
8775 | assert_eq!(ARMED_FLAGS.len(), DISARMED_FLAGS.len()); |
8776 | |
8777 | let map: HashMap<u64, CheckedCloneDrop<Vec<u64>>, DefaultHashBuilder, MyAlloc> = |
8778 | match get_test_map( |
8779 | ARMED_FLAGS.into_iter().zip(DISARMED_FLAGS), |
8780 | |n| vec![n], |
8781 | MyAlloc::new(dropped.clone()), |
8782 | ) { |
8783 | Ok(map) => map, |
8784 | Err(msg) => panic!("{msg}" ), |
8785 | }; |
8786 | |
8787 | // Clone should normally clone a few elements, and then (when the |
8788 | // clone function panics), deallocate both its own memory, memory |
8789 | // of `dropped: Arc<AtomicI8>` and the memory of already cloned |
8790 | // elements (Vec<i32> memory inside CheckedCloneDrop). |
8791 | let _map2 = map.clone(); |
8792 | } |
8793 | } |
8794 | |
8795 | #[test] |
8796 | #[should_panic = "panic in drop" ] |
8797 | fn test_clone_memory_leaks_and_double_drop_two() { |
8798 | let dropped: Arc<AtomicI8> = Arc::new(AtomicI8::new(2)); |
8799 | |
8800 | { |
8801 | assert_eq!(ARMED_FLAGS.len(), DISARMED_FLAGS.len()); |
8802 | |
8803 | let map: HashMap<u64, CheckedCloneDrop<u64>, DefaultHashBuilder, _> = match get_test_map( |
8804 | DISARMED_FLAGS.into_iter().zip(DISARMED_FLAGS), |
8805 | |n| n, |
8806 | MyAlloc::new(dropped.clone()), |
8807 | ) { |
8808 | Ok(map) => map, |
8809 | Err(msg) => panic!("{msg}" ), |
8810 | }; |
8811 | |
8812 | let mut map2 = match get_test_map( |
8813 | DISARMED_FLAGS.into_iter().zip(ARMED_FLAGS), |
8814 | |n| n, |
8815 | MyAlloc::new(dropped.clone()), |
8816 | ) { |
8817 | Ok(map) => map, |
8818 | Err(msg) => panic!("{msg}" ), |
8819 | }; |
8820 | |
8821 | // The `clone_from` should try to drop the elements of `map2` without |
8822 | // double drop and leaking the allocator. Elements that have not been |
8823 | // dropped leak their memory. |
8824 | map2.clone_from(&map); |
8825 | } |
8826 | } |
8827 | |
8828 | /// We check that we have a working table if the clone operation from another |
8829 | /// thread ended in a panic (when buckets of maps are equal to each other). |
8830 | #[test] |
8831 | fn test_catch_panic_clone_from_when_len_is_equal() { |
8832 | use std::thread; |
8833 | |
8834 | let dropped: Arc<AtomicI8> = Arc::new(AtomicI8::new(2)); |
8835 | |
8836 | { |
8837 | assert_eq!(ARMED_FLAGS.len(), DISARMED_FLAGS.len()); |
8838 | |
8839 | let mut map = match get_test_map( |
8840 | DISARMED_FLAGS.into_iter().zip(DISARMED_FLAGS), |
8841 | |n| vec![n], |
8842 | MyAlloc::new(dropped.clone()), |
8843 | ) { |
8844 | Ok(map) => map, |
8845 | Err(msg) => panic!("{msg}" ), |
8846 | }; |
8847 | |
8848 | thread::scope(|s| { |
8849 | let result: thread::ScopedJoinHandle<'_, String> = s.spawn(|| { |
8850 | let scope_map = |
8851 | match get_test_map(ARMED_FLAGS.into_iter().zip(DISARMED_FLAGS), |n| vec![n * 2], MyAlloc::new(dropped.clone())) { |
8852 | Ok(map) => map, |
8853 | Err(msg) => return msg, |
8854 | }; |
8855 | if map.table.buckets() != scope_map.table.buckets() { |
8856 | return format!( |
8857 | "map.table.buckets() != scope_map.table.buckets(), \nleft: `{}`, \nright: `{}`" , |
8858 | map.table.buckets(), scope_map.table.buckets() |
8859 | ); |
8860 | } |
8861 | map.clone_from(&scope_map); |
8862 | "We must fail the cloning!!!" .to_owned() |
8863 | }); |
8864 | if let Ok(msg) = result.join() { |
8865 | panic!("{msg}" ) |
8866 | } |
8867 | }); |
8868 | |
8869 | // Let's check that all iterators work fine and do not return elements |
8870 | // (especially `RawIterRange`, which does not depend on the number of |
8871 | // elements in the table, but looks directly at the control bytes) |
8872 | // |
8873 | // SAFETY: We know for sure that `RawTable` will outlive |
8874 | // the returned `RawIter / RawIterRange` iterator. |
8875 | assert_eq!(map.len(), 0); |
8876 | assert_eq!(map.iter().count(), 0); |
8877 | assert_eq!(unsafe { map.table.iter().count() }, 0); |
8878 | assert_eq!(unsafe { map.table.iter().iter.count() }, 0); |
8879 | |
8880 | for idx in 0..map.table.buckets() { |
8881 | let idx = idx as u64; |
8882 | assert!( |
8883 | map.table.find(idx, |(k, _)| *k == idx).is_none(), |
8884 | "Index: {idx}" |
8885 | ); |
8886 | } |
8887 | } |
8888 | |
8889 | // All allocator clones should already be dropped. |
8890 | assert_eq!(dropped.load(Ordering::SeqCst), 0); |
8891 | } |
8892 | |
8893 | /// We check that we have a working table if the clone operation from another |
8894 | /// thread ended in a panic (when buckets of maps are not equal to each other). |
8895 | #[test] |
8896 | fn test_catch_panic_clone_from_when_len_is_not_equal() { |
8897 | use std::thread; |
8898 | |
8899 | let dropped: Arc<AtomicI8> = Arc::new(AtomicI8::new(2)); |
8900 | |
8901 | { |
8902 | assert_eq!(ARMED_FLAGS.len(), DISARMED_FLAGS.len()); |
8903 | |
8904 | let mut map = match get_test_map( |
8905 | [DISARMED].into_iter().zip([DISARMED]), |
8906 | |n| vec![n], |
8907 | MyAlloc::new(dropped.clone()), |
8908 | ) { |
8909 | Ok(map) => map, |
8910 | Err(msg) => panic!("{msg}" ), |
8911 | }; |
8912 | |
8913 | thread::scope(|s| { |
8914 | let result: thread::ScopedJoinHandle<'_, String> = s.spawn(|| { |
8915 | let scope_map = match get_test_map( |
8916 | ARMED_FLAGS.into_iter().zip(DISARMED_FLAGS), |
8917 | |n| vec![n * 2], |
8918 | MyAlloc::new(dropped.clone()), |
8919 | ) { |
8920 | Ok(map) => map, |
8921 | Err(msg) => return msg, |
8922 | }; |
8923 | if map.table.buckets() == scope_map.table.buckets() { |
8924 | return format!( |
8925 | "map.table.buckets() == scope_map.table.buckets(): `{}`" , |
8926 | map.table.buckets() |
8927 | ); |
8928 | } |
8929 | map.clone_from(&scope_map); |
8930 | "We must fail the cloning!!!" .to_owned() |
8931 | }); |
8932 | if let Ok(msg) = result.join() { |
8933 | panic!("{msg}" ) |
8934 | } |
8935 | }); |
8936 | |
8937 | // Let's check that all iterators work fine and do not return elements |
8938 | // (especially `RawIterRange`, which does not depend on the number of |
8939 | // elements in the table, but looks directly at the control bytes) |
8940 | // |
8941 | // SAFETY: We know for sure that `RawTable` will outlive |
8942 | // the returned `RawIter / RawIterRange` iterator. |
8943 | assert_eq!(map.len(), 0); |
8944 | assert_eq!(map.iter().count(), 0); |
8945 | assert_eq!(unsafe { map.table.iter().count() }, 0); |
8946 | assert_eq!(unsafe { map.table.iter().iter.count() }, 0); |
8947 | |
8948 | for idx in 0..map.table.buckets() { |
8949 | let idx = idx as u64; |
8950 | assert!( |
8951 | map.table.find(idx, |(k, _)| *k == idx).is_none(), |
8952 | "Index: {idx}" |
8953 | ); |
8954 | } |
8955 | } |
8956 | |
8957 | // All allocator clones should already be dropped. |
8958 | assert_eq!(dropped.load(Ordering::SeqCst), 0); |
8959 | } |
8960 | } |
8961 | |