1 | use std::fmt; |
2 | |
3 | use crate::{capitalize, lowercase, transform}; |
4 | |
5 | /// This trait defines a lower camel case conversion. |
6 | /// |
7 | /// In lowerCamelCase, word boundaries are indicated by capital letters, |
8 | /// excepting the first word. |
9 | /// |
10 | /// ## Example: |
11 | /// |
12 | /// ```rust |
13 | /// use heck::ToLowerCamelCase; |
14 | /// |
15 | /// let sentence = "It is we who built these palaces and cities." ; |
16 | /// assert_eq!(sentence.to_lower_camel_case(), "itIsWeWhoBuiltThesePalacesAndCities" ); |
17 | /// ``` |
18 | pub trait ToLowerCamelCase: ToOwned { |
19 | /// Convert this type to lower camel case. |
20 | fn to_lower_camel_case(&self) -> Self::Owned; |
21 | } |
22 | |
23 | impl ToLowerCamelCase for str { |
24 | fn to_lower_camel_case(&self) -> String { |
25 | AsLowerCamelCase(self).to_string() |
26 | } |
27 | } |
28 | |
29 | /// This wrapper performs a lower camel case conversion in [`fmt::Display`]. |
30 | /// |
31 | /// ## Example: |
32 | /// |
33 | /// ``` |
34 | /// use heck::AsLowerCamelCase; |
35 | /// |
36 | /// let sentence = "It is we who built these palaces and cities." ; |
37 | /// assert_eq!(format!("{}" , AsLowerCamelCase(sentence)), "itIsWeWhoBuiltThesePalacesAndCities" ); |
38 | /// ``` |
39 | pub struct AsLowerCamelCase<T: AsRef<str>>(pub T); |
40 | |
41 | impl<T: AsRef<str>> fmt::Display for AsLowerCamelCase<T> { |
42 | fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
43 | let mut first: bool = true; |
44 | transform( |
45 | self.0.as_ref(), |
46 | |s, f| { |
47 | if first { |
48 | first = false; |
49 | lowercase(s, f) |
50 | } else { |
51 | capitalize(s, f) |
52 | } |
53 | }, |
54 | |_| Ok(()), |
55 | f, |
56 | ) |
57 | } |
58 | } |
59 | |
60 | #[cfg (test)] |
61 | mod tests { |
62 | use super::ToLowerCamelCase; |
63 | |
64 | macro_rules! t { |
65 | ($t:ident : $s1:expr => $s2:expr) => { |
66 | #[test] |
67 | fn $t() { |
68 | assert_eq!($s1.to_lower_camel_case(), $s2) |
69 | } |
70 | }; |
71 | } |
72 | |
73 | t!(test1: "CamelCase" => "camelCase" ); |
74 | t!(test2: "This is Human case." => "thisIsHumanCase" ); |
75 | t!(test3: "MixedUP CamelCase, with some Spaces" => "mixedUpCamelCaseWithSomeSpaces" ); |
76 | t!(test4: "mixed_up_ snake_case, with some _spaces" => "mixedUpSnakeCaseWithSomeSpaces" ); |
77 | t!(test5: "kebab-case" => "kebabCase" ); |
78 | t!(test6: "SHOUTY_SNAKE_CASE" => "shoutySnakeCase" ); |
79 | t!(test7: "snake_case" => "snakeCase" ); |
80 | t!(test8: "this-contains_ ALLKinds OfWord_Boundaries" => "thisContainsAllKindsOfWordBoundaries" ); |
81 | #[cfg (feature = "unicode" )] |
82 | t!(test9: "XΣXΣ baffle" => "xσxςBaffle" ); |
83 | t!(test10: "XMLHttpRequest" => "xmlHttpRequest" ); |
84 | // TODO unicode tests |
85 | } |
86 | |