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29
30	// Google Mock - a framework for writing C++ mock classes.
31	//
32	// The MATCHER* family of macros can be used in a namespace scope to
33	// define custom matchers easily.
34	//
35	// Basic Usage
36	// ===========
37	//
38	// The syntax
39	//
40	// MATCHER(name, description_string) { statements; }
41	//
42	// defines a matcher with the given name that executes the statements,
43	// which must return a bool to indicate if the match succeeds. Inside
44	// the statements, you can refer to the value being matched by 'arg',
45	// and refer to its type by 'arg_type'.
46	//
47	// The description string documents what the matcher does, and is used
48	// to generate the failure message when the match fails. Since a
49	// MATCHER() is usually defined in a header file shared by multiple
50	// C++ source files, we require the description to be a C-string
51	// literal to avoid possible side effects. It can be empty, in which
52	// case we'll use the sequence of words in the matcher name as the
53	// description.
54	//
55	// For example:
56	//
57	// MATCHER(IsEven, "") { return (arg % 2) == 0; }
58	//
59	// allows you to write
60	//
61	// // Expects mock_foo.Bar(n) to be called where n is even.
62	// EXPECT_CALL(mock_foo, Bar(IsEven()));
63	//
64	// or,
65	//
66	// // Verifies that the value of some_expression is even.
67	// EXPECT_THAT(some_expression, IsEven());
68	//
69	// If the above assertion fails, it will print something like:
70	//
71	// Value of: some_expression
72	// Expected: is even
73	// Actual: 7
74	//
75	// where the description "is even" is automatically calculated from the
76	// matcher name IsEven.
77	//
78	// Argument Type
79	// =============
80	//
81	// Note that the type of the value being matched (arg_type) is
82	// determined by the context in which you use the matcher and is
83	// supplied to you by the compiler, so you don't need to worry about
84	// declaring it (nor can you). This allows the matcher to be
85	// polymorphic. For example, IsEven() can be used to match any type
86	// where the value of "(arg % 2) == 0" can be implicitly converted to
87	// a bool. In the "Bar(IsEven())" example above, if method Bar()
88	// takes an int, 'arg_type' will be int; if it takes an unsigned long,
89	// 'arg_type' will be unsigned long; and so on.
90	//
91	// Parameterizing Matchers
92	// =======================
93	//
94	// Sometimes you'll want to parameterize the matcher. For that you
95	// can use another macro:
96	//
97	// MATCHER_P(name, param_name, description_string) { statements; }
98	//
99	// For example:
100	//
101	// MATCHER_P(HasAbsoluteValue, value, "") { return abs(arg) == value; }
102	//
103	// will allow you to write:
104	//
105	// EXPECT_THAT(Blah("a"), HasAbsoluteValue(n));
106	//
107	// which may lead to this message (assuming n is 10):
108	//
109	// Value of: Blah("a")
110	// Expected: has absolute value 10
111	// Actual: -9
112	//
113	// Note that both the matcher description and its parameter are
114	// printed, making the message human-friendly.
115	//
116	// In the matcher definition body, you can write 'foo_type' to
117	// reference the type of a parameter named 'foo'. For example, in the
118	// body of MATCHER_P(HasAbsoluteValue, value) above, you can write
119	// 'value_type' to refer to the type of 'value'.
120	//
121	// We also provide MATCHER_P2, MATCHER_P3, ..., up to MATCHER_P$n to
122	// support multi-parameter matchers.
123	//
124	// Describing Parameterized Matchers
125	// =================================
126	//
127	// The last argument to MATCHER*() is a string-typed expression. The
128	// expression can reference all of the matcher's parameters and a
129	// special bool-typed variable named 'negation'. When 'negation' is
130	// false, the expression should evaluate to the matcher's description;
131	// otherwise it should evaluate to the description of the negation of
132	// the matcher. For example,
133	//
134	// using testing::PrintToString;
135	//
136	// MATCHER_P2(InClosedRange, low, hi,
137	// std::string(negation ? "is not" : "is") + " in range [" +
138	// PrintToString(low) + ", " + PrintToString(hi) + "]") {
139	// return low <= arg && arg <= hi;
140	// }
141	// ...
142	// EXPECT_THAT(3, InClosedRange(4, 6));
143	// EXPECT_THAT(3, Not(InClosedRange(2, 4)));
144	//
145	// would generate two failures that contain the text:
146	//
147	// Expected: is in range [4, 6]
148	// ...
149	// Expected: is not in range [2, 4]
150	//
151	// If you specify "" as the description, the failure message will
152	// contain the sequence of words in the matcher name followed by the
153	// parameter values printed as a tuple. For example,
154	//
155	// MATCHER_P2(InClosedRange, low, hi, "") { ... }
156	// ...
157	// EXPECT_THAT(3, InClosedRange(4, 6));
158	// EXPECT_THAT(3, Not(InClosedRange(2, 4)));
159	//
160	// would generate two failures that contain the text:
161	//
162	// Expected: in closed range (4, 6)
163	// ...
164	// Expected: not (in closed range (2, 4))
165	//
166	// Types of Matcher Parameters
167	// ===========================
168	//
169	// For the purpose of typing, you can view
170	//
171	// MATCHER_Pk(Foo, p1, ..., pk, description_string) { ... }
172	//
173	// as shorthand for
174	//
175	// template <typename p1_type, ..., typename pk_type>
176	// FooMatcherPk<p1_type, ..., pk_type>
177	// Foo(p1_type p1, ..., pk_type pk) { ... }
178	//
179	// When you write Foo(v1, ..., vk), the compiler infers the types of
180	// the parameters v1, ..., and vk for you. If you are not happy with
181	// the result of the type inference, you can specify the types by
182	// explicitly instantiating the template, as in Foo<long, bool>(5,
183	// false). As said earlier, you don't get to (or need to) specify
184	// 'arg_type' as that's determined by the context in which the matcher
185	// is used. You can assign the result of expression Foo(p1, ..., pk)
186	// to a variable of type FooMatcherPk<p1_type, ..., pk_type>. This
187	// can be useful when composing matchers.
188	//
189	// While you can instantiate a matcher template with reference types,
190	// passing the parameters by pointer usually makes your code more
191	// readable. If, however, you still want to pass a parameter by
192	// reference, be aware that in the failure message generated by the
193	// matcher you will see the value of the referenced object but not its
194	// address.
195	//
196	// Explaining Match Results
197	// ========================
198	//
199	// Sometimes the matcher description alone isn't enough to explain why
200	// the match has failed or succeeded. For example, when expecting a
201	// long string, it can be very helpful to also print the diff between
202	// the expected string and the actual one. To achieve that, you can
203	// optionally stream additional information to a special variable
204	// named result_listener, whose type is a pointer to class
205	// MatchResultListener:
206	//
207	// MATCHER_P(EqualsLongString, str, "") {
208	// if (arg == str) return true;
209	//
210	// *result_listener << "the difference: "
211	/// << DiffStrings(str, arg);
212	// return false;
213	// }
214	//
215	// Overloading Matchers
216	// ====================
217	//
218	// You can overload matchers with different numbers of parameters:
219	//
220	// MATCHER_P(Blah, a, description_string1) { ... }
221	// MATCHER_P2(Blah, a, b, description_string2) { ... }
222	//
223	// Caveats
224	// =======
225	//
226	// When defining a new matcher, you should also consider implementing
227	// MatcherInterface or using MakePolymorphicMatcher(). These
228	// approaches require more work than the MATCHER* macros, but also
229	// give you more control on the types of the value being matched and
230	// the matcher parameters, which may leads to better compiler error
231	// messages when the matcher is used wrong. They also allow
232	// overloading matchers based on parameter types (as opposed to just
233	// based on the number of parameters).
234	//
235	// MATCHER*() can only be used in a namespace scope as templates cannot be
236	// declared inside of a local class.
237	//
238	// More Information
239	// ================
240	//
241	// To learn more about using these macros, please search for 'MATCHER'
242	// on
243	// https://github.com/google/googletest/blob/main/docs/gmock_cook_book.md
244	//
245	// This file also implements some commonly used argument matchers. More
246	// matchers can be defined by the user implementing the
247	// MatcherInterface<T> interface if necessary.
248	//
249	// See googletest/include/gtest/gtest-matchers.h for the definition of class
250	// Matcher, class MatcherInterface, and others.
251
252	// IWYU pragma: private, include "gmock/gmock.h"
253	// IWYU pragma: friend gmock/.*
254
255	#ifndef GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_MATCHERS_H_
256	#define GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_MATCHERS_H_
257
258	#include <algorithm>
259	#include <cmath>
260	#include <exception>
261	#include <functional>
262	#include <initializer_list>
263	#include <ios>
264	#include <iterator>
265	#include <limits>
266	#include <memory>
267	#include <ostream> // NOLINT
268	#include <sstream>
269	#include <string>
270	#include <type_traits>
271	#include <utility>
272	#include <vector>
273
274	#include "gmock/internal/gmock-internal-utils.h"
275	#include "gmock/internal/gmock-port.h"
276	#include "gmock/internal/gmock-pp.h"
277	#include "gtest/gtest.h"
278
279	// MSVC warning C5046 is new as of VS2017 version 15.8.
280	#if defined(_MSC_VER) && _MSC_VER >= 1915
281	#define GMOCK_MAYBE_5046_ 5046
282	#else
283	#define GMOCK_MAYBE_5046_
284	#endif
285
286	GTEST_DISABLE_MSC_WARNINGS_PUSH_(
287	4251 GMOCK_MAYBE_5046_ /* class A needs to have dll-interface to be used by
288	clients of class B */
289	/* Symbol involving type with internal linkage not defined */)
290
291	namespace testing {
292
293	// To implement a matcher Foo for type T, define:
294	// 1. a class FooMatcherImpl that implements the
295	// MatcherInterface<T> interface, and
296	// 2. a factory function that creates a Matcher<T> object from a
297	// FooMatcherImpl*.
298	//
299	// The two-level delegation design makes it possible to allow a user
300	// to write "v" instead of "Eq(v)" where a Matcher is expected, which
301	// is impossible if we pass matchers by pointers. It also eases
302	// ownership management as Matcher objects can now be copied like
303	// plain values.
304
305	// A match result listener that stores the explanation in a string.
306	class StringMatchResultListener : public MatchResultListener {
307	public:
308	StringMatchResultListener() : MatchResultListener(&ss_) {}
309
310	// Returns the explanation accumulated so far.
311	std::string str() const { return ss_.str(); }
312
313	// Clears the explanation accumulated so far.
314	void Clear() { ss_.str(s: ""); }
315
316	private:
317	::std::stringstream ss_;
318
319	StringMatchResultListener(const StringMatchResultListener&) = delete;
320	StringMatchResultListener& operator=(const StringMatchResultListener&) =
321	delete;
322	};
323
324	// Anything inside the 'internal' namespace IS INTERNAL IMPLEMENTATION
325	// and MUST NOT BE USED IN USER CODE!!!
326	namespace internal {
327
328	// The MatcherCastImpl class template is a helper for implementing
329	// MatcherCast(). We need this helper in order to partially
330	// specialize the implementation of MatcherCast() (C++ allows
331	// class/struct templates to be partially specialized, but not
332	// function templates.).
333
334	// This general version is used when MatcherCast()'s argument is a
335	// polymorphic matcher (i.e. something that can be converted to a
336	// Matcher but is not one yet; for example, Eq(value)) or a value (for
337	// example, "hello").
338	template <typename T, typename M>
339	class MatcherCastImpl {
340	public:
341	static Matcher<T> Cast(const M& polymorphic_matcher_or_value) {
342	// M can be a polymorphic matcher, in which case we want to use
343	// its conversion operator to create Matcher<T>. Or it can be a value
344	// that should be passed to the Matcher<T>'s constructor.
345	//
346	// We can't call Matcher<T>(polymorphic_matcher_or_value) when M is a
347	// polymorphic matcher because it'll be ambiguous if T has an implicit
348	// constructor from M (this usually happens when T has an implicit
349	// constructor from any type).
350	//
351	// It won't work to unconditionally implicit_cast
352	// polymorphic_matcher_or_value to Matcher<T> because it won't trigger
353	// a user-defined conversion from M to T if one exists (assuming M is
354	// a value).
355	return CastImpl(polymorphic_matcher_or_value,
356	std::is_convertible<M, Matcher<T>>{},
357	std::is_convertible<M, T>{});
358	}
359
360	private:
361	template <bool Ignore>
362	static Matcher<T> CastImpl(const M& polymorphic_matcher_or_value,
363	std::true_type /* convertible_to_matcher */,
364	std::integral_constant<bool, Ignore>) {
365	// M is implicitly convertible to Matcher<T>, which means that either
366	// M is a polymorphic matcher or Matcher<T> has an implicit constructor
367	// from M. In both cases using the implicit conversion will produce a
368	// matcher.
369	//
370	// Even if T has an implicit constructor from M, it won't be called because
371	// creating Matcher<T> would require a chain of two user-defined conversions
372	// (first to create T from M and then to create Matcher<T> from T).
373	return polymorphic_matcher_or_value;
374	}
375
376	// M can't be implicitly converted to Matcher<T>, so M isn't a polymorphic
377	// matcher. It's a value of a type implicitly convertible to T. Use direct
378	// initialization to create a matcher.
379	static Matcher<T> CastImpl(const M& value,
380	std::false_type /* convertible_to_matcher */,
381	std::true_type /* convertible_to_T */) {
382	return Matcher<T>(ImplicitCast_<T>(value));
383	}
384
385	// M can't be implicitly converted to either Matcher<T> or T. Attempt to use
386	// polymorphic matcher Eq(value) in this case.
387	//
388	// Note that we first attempt to perform an implicit cast on the value and
389	// only fall back to the polymorphic Eq() matcher afterwards because the
390	// latter calls bool operator==(const Lhs& lhs, const Rhs& rhs) in the end
391	// which might be undefined even when Rhs is implicitly convertible to Lhs
392	// (e.g. std::pair<const int, int> vs. std::pair<int, int>).
393	//
394	// We don't define this method inline as we need the declaration of Eq().
395	static Matcher<T> CastImpl(const M& value,
396	std::false_type /* convertible_to_matcher */,
397	std::false_type /* convertible_to_T */);
398	};
399
400	// This more specialized version is used when MatcherCast()'s argument
401	// is already a Matcher. This only compiles when type T can be
402	// statically converted to type U.
403	template <typename T, typename U>
404	class MatcherCastImpl<T, Matcher<U>> {
405	public:
406	static Matcher<T> Cast(const Matcher<U>& source_matcher) {
407	return Matcher<T>(new Impl(source_matcher));
408	}
409
410	private:
411	class Impl : public MatcherInterface<T> {
412	public:
413	explicit Impl(const Matcher<U>& source_matcher)
414	: source_matcher_(source_matcher) {}
415
416	// We delegate the matching logic to the source matcher.
417	bool MatchAndExplain(T x, MatchResultListener* listener) const override {
418	using FromType = typename std::remove_cv<typename std::remove_pointer<
419	typename std::remove_reference<T>::type>::type>::type;
420	using ToType = typename std::remove_cv<typename std::remove_pointer<
421	typename std::remove_reference<U>::type>::type>::type;
422	// Do not allow implicitly converting base*/& to derived*/&.
423	static_assert(
424	// Do not trigger if only one of them is a pointer. That implies a
425	// regular conversion and not a down_cast.
426	(std::is_pointer<typename std::remove_reference<T>::type>::value !=
427	std::is_pointer<typename std::remove_reference<U>::type>::value) ||
428	std::is_same<FromType, ToType>::value ||
429	!std::is_base_of<FromType, ToType>::value,
430	"Can't implicitly convert from <base> to <derived>");
431
432	// Do the cast to `U` explicitly if necessary.
433	// Otherwise, let implicit conversions do the trick.
434	using CastType =
435	typename std::conditional<std::is_convertible<T&, const U&>::value,
436	T&, U>::type;
437
438	return source_matcher_.MatchAndExplain(static_cast<CastType>(x),
439	listener);
440	}
441
442	void DescribeTo(::std::ostream* os) const override {
443	source_matcher_.DescribeTo(os);
444	}
445
446	void DescribeNegationTo(::std::ostream* os) const override {
447	source_matcher_.DescribeNegationTo(os);
448	}
449
450	private:
451	const Matcher<U> source_matcher_;
452	};
453	};
454
455	// This even more specialized version is used for efficiently casting
456	// a matcher to its own type.
457	template <typename T>
458	class MatcherCastImpl<T, Matcher<T>> {
459	public:
460	static Matcher<T> Cast(const Matcher<T>& matcher) { return matcher; }
461	};
462
463	// Template specialization for parameterless Matcher.
464	template <typename Derived>
465	class MatcherBaseImpl {
466	public:
467	MatcherBaseImpl() = default;
468
469	template <typename T>
470	operator ::testing::Matcher<T>() const { // NOLINT(runtime/explicit)
471	return ::testing::Matcher<T>(new
472	typename Derived::template gmock_Impl<T>());
473	}
474	};
475
476	// Template specialization for Matcher with parameters.
477	template <template <typename...> class Derived, typename... Ts>
478	class MatcherBaseImpl<Derived<Ts...>> {
479	public:
480	// Mark the constructor explicit for single argument T to avoid implicit
481	// conversions.
482	template <typename E = std::enable_if<sizeof...(Ts) == 1>,
483	typename E::type* = nullptr>
484	explicit MatcherBaseImpl(Ts... params)
485	: params_(std::forward<Ts>(params)...) {}
486	template <typename E = std::enable_if<sizeof...(Ts) != 1>,
487	typename = typename E::type>
488	MatcherBaseImpl(Ts... params) // NOLINT
489	: params_(std::forward<Ts>(params)...) {}
490
491	template <typename F>
492	operator ::testing::Matcher<F>() const { // NOLINT(runtime/explicit)
493	return Apply<F>(MakeIndexSequence<sizeof...(Ts)>{});
494	}
495
496	private:
497	template <typename F, std::size_t... tuple_ids>
498	::testing::Matcher<F> Apply(IndexSequence<tuple_ids...>) const {
499	return ::testing::Matcher<F>(
500	new typename Derived<Ts...>::template gmock_Impl<F>(
501	std::get<tuple_ids>(params_)...));
502	}
503
504	const std::tuple<Ts...> params_;
505	};
506
507	} // namespace internal
508
509	// In order to be safe and clear, casting between different matcher
510	// types is done explicitly via MatcherCast<T>(m), which takes a
511	// matcher m and returns a Matcher<T>. It compiles only when T can be
512	// statically converted to the argument type of m.
513	template <typename T, typename M>
514	inline Matcher<T> MatcherCast(const M& matcher) {
515	return internal::MatcherCastImpl<T, M>::Cast(matcher);
516	}
517
518	// This overload handles polymorphic matchers and values only since
519	// monomorphic matchers are handled by the next one.
520	template <typename T, typename M>
521	inline Matcher<T> SafeMatcherCast(const M& polymorphic_matcher_or_value) {
522	return MatcherCast<T>(polymorphic_matcher_or_value);
523	}
524
525	// This overload handles monomorphic matchers.
526	//
527	// In general, if type T can be implicitly converted to type U, we can
528	// safely convert a Matcher<U> to a Matcher<T> (i.e. Matcher is
529	// contravariant): just keep a copy of the original Matcher<U>, convert the
530	// argument from type T to U, and then pass it to the underlying Matcher<U>.
531	// The only exception is when U is a reference and T is not, as the
532	// underlying Matcher<U> may be interested in the argument's address, which
533	// is not preserved in the conversion from T to U.
534	template <typename T, typename U>
535	inline Matcher<T> SafeMatcherCast(const Matcher<U>& matcher) {
536	// Enforce that T can be implicitly converted to U.
537	static_assert(std::is_convertible<const T&, const U&>::value,
538	"T must be implicitly convertible to U");
539	// Enforce that we are not converting a non-reference type T to a reference
540	// type U.
541	static_assert(std::is_reference<T>::value || !std::is_reference<U>::value,
542	"cannot convert non reference arg to reference");
543	// In case both T and U are arithmetic types, enforce that the
544	// conversion is not lossy.
545	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(T) RawT;
546	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(U) RawU;
547	constexpr bool kTIsOther = GMOCK_KIND_OF_(RawT) == internal::kOther;
548	constexpr bool kUIsOther = GMOCK_KIND_OF_(RawU) == internal::kOther;
549	static_assert(
550	kTIsOther || kUIsOther ||
551	(internal::LosslessArithmeticConvertible<RawT, RawU>::value),
552	"conversion of arithmetic types must be lossless");
553	return MatcherCast<T>(matcher);
554	}
555
556	// A<T>() returns a matcher that matches any value of type T.
557	template <typename T>
558	Matcher<T> A();
559
560	// Anything inside the 'internal' namespace IS INTERNAL IMPLEMENTATION
561	// and MUST NOT BE USED IN USER CODE!!!
562	namespace internal {
563
564	// If the explanation is not empty, prints it to the ostream.
565	inline void PrintIfNotEmpty(const std::string& explanation,
566	::std::ostream* os) {
567	if (!explanation.empty() && os != nullptr) {
568	*os << ", " << explanation;
569	}
570	}
571
572	// Returns true if the given type name is easy to read by a human.
573	// This is used to decide whether printing the type of a value might
574	// be helpful.
575	inline bool IsReadableTypeName(const std::string& type_name) {
576	// We consider a type name readable if it's short or doesn't contain
577	// a template or function type.
578	return (type_name.length() <= 20 ||
579	type_name.find_first_of(s: "<(") == std::string::npos);
580	}
581
582	// Matches the value against the given matcher, prints the value and explains
583	// the match result to the listener. Returns the match result.
584	// 'listener' must not be NULL.
585	// Value cannot be passed by const reference, because some matchers take a
586	// non-const argument.
587	template <typename Value, typename T>
588	bool MatchPrintAndExplain(Value& value, const Matcher<T>& matcher,
589	MatchResultListener* listener) {
590	if (!listener->IsInterested()) {
591	// If the listener is not interested, we do not need to construct the
592	// inner explanation.
593	return matcher.Matches(value);
594	}
595
596	StringMatchResultListener inner_listener;
597	const bool match = matcher.MatchAndExplain(value, &inner_listener);
598
599	UniversalPrint(value, listener->stream());
600	#if GTEST_HAS_RTTI
601	const std::string& type_name = GetTypeName<Value>();
602	if (IsReadableTypeName(type_name))
603	*listener->stream() << " (of type " << type_name << ")";
604	#endif
605	PrintIfNotEmpty(explanation: inner_listener.str(), os: listener->stream());
606
607	return match;
608	}
609
610	// An internal helper class for doing compile-time loop on a tuple's
611	// fields.
612	template <size_t N>
613	class TuplePrefix {
614	public:
615	// TuplePrefix<N>::Matches(matcher_tuple, value_tuple) returns true
616	// if and only if the first N fields of matcher_tuple matches
617	// the first N fields of value_tuple, respectively.
618	template <typename MatcherTuple, typename ValueTuple>
619	static bool Matches(const MatcherTuple& matcher_tuple,
620	const ValueTuple& value_tuple) {
621	return TuplePrefix<N - 1>::Matches(matcher_tuple, value_tuple) &&
622	std::get<N - 1>(matcher_tuple).Matches(std::get<N - 1>(value_tuple));
623	}
624
625	// TuplePrefix<N>::ExplainMatchFailuresTo(matchers, values, os)
626	// describes failures in matching the first N fields of matchers
627	// against the first N fields of values. If there is no failure,
628	// nothing will be streamed to os.
629	template <typename MatcherTuple, typename ValueTuple>
630	static void ExplainMatchFailuresTo(const MatcherTuple& matchers,
631	const ValueTuple& values,
632	::std::ostream* os) {
633	// First, describes failures in the first N - 1 fields.
634	TuplePrefix<N - 1>::ExplainMatchFailuresTo(matchers, values, os);
635
636	// Then describes the failure (if any) in the (N - 1)-th (0-based)
637	// field.
638	typename std::tuple_element<N - 1, MatcherTuple>::type matcher =
639	std::get<N - 1>(matchers);
640	typedef typename std::tuple_element<N - 1, ValueTuple>::type Value;
641	const Value& value = std::get<N - 1>(values);
642	StringMatchResultListener listener;
643	if (!matcher.MatchAndExplain(value, &listener)) {
644	*os << " Expected arg #" << N - 1 << ": ";
645	std::get<N - 1>(matchers).DescribeTo(os);
646	*os << "\n Actual: ";
647	// We remove the reference in type Value to prevent the
648	// universal printer from printing the address of value, which
649	// isn't interesting to the user most of the time. The
650	// matcher's MatchAndExplain() method handles the case when
651	// the address is interesting.
652	internal::UniversalPrint(value, os);
653	PrintIfNotEmpty(explanation: listener.str(), os);
654	*os << "\n";
655	}
656	}
657	};
658
659	// The base case.
660	template <>
661	class TuplePrefix<0> {
662	public:
663	template <typename MatcherTuple, typename ValueTuple>
664	static bool Matches(const MatcherTuple& /* matcher_tuple */,
665	const ValueTuple& /* value_tuple */) {
666	return true;
667	}
668
669	template <typename MatcherTuple, typename ValueTuple>
670	static void ExplainMatchFailuresTo(const MatcherTuple& /* matchers */,
671	const ValueTuple& /* values */,
672	::std::ostream* /* os */) {}
673	};
674
675	// TupleMatches(matcher_tuple, value_tuple) returns true if and only if
676	// all matchers in matcher_tuple match the corresponding fields in
677	// value_tuple. It is a compiler error if matcher_tuple and
678	// value_tuple have different number of fields or incompatible field
679	// types.
680	template <typename MatcherTuple, typename ValueTuple>
681	bool TupleMatches(const MatcherTuple& matcher_tuple,
682	const ValueTuple& value_tuple) {
683	// Makes sure that matcher_tuple and value_tuple have the same
684	// number of fields.
685	static_assert(std::tuple_size<MatcherTuple>::value ==
686	std::tuple_size<ValueTuple>::value,
687	"matcher and value have different numbers of fields");
688	return TuplePrefix<std::tuple_size<ValueTuple>::value>::Matches(matcher_tuple,
689	value_tuple);
690	}
691
692	// Describes failures in matching matchers against values. If there
693	// is no failure, nothing will be streamed to os.
694	template <typename MatcherTuple, typename ValueTuple>
695	void ExplainMatchFailureTupleTo(const MatcherTuple& matchers,
696	const ValueTuple& values, ::std::ostream* os) {
697	TuplePrefix<std::tuple_size<MatcherTuple>::value>::ExplainMatchFailuresTo(
698	matchers, values, os);
699	}
700
701	// TransformTupleValues and its helper.
702	//
703	// TransformTupleValuesHelper hides the internal machinery that
704	// TransformTupleValues uses to implement a tuple traversal.
705	template <typename Tuple, typename Func, typename OutIter>
706	class TransformTupleValuesHelper {
707	private:
708	typedef ::std::tuple_size<Tuple> TupleSize;
709
710	public:
711	// For each member of tuple 't', taken in order, evaluates '*out++ = f(t)'.
712	// Returns the final value of 'out' in case the caller needs it.
713	static OutIter Run(Func f, const Tuple& t, OutIter out) {
714	return IterateOverTuple<Tuple, TupleSize::value>()(f, t, out);
715	}
716
717	private:
718	template <typename Tup, size_t kRemainingSize>
719	struct IterateOverTuple {
720	OutIter operator()(Func f, const Tup& t, OutIter out) const {
721	*out++ = f(::std::get<TupleSize::value - kRemainingSize>(t));
722	return IterateOverTuple<Tup, kRemainingSize - 1>()(f, t, out);
723	}
724	};
725	template <typename Tup>
726	struct IterateOverTuple<Tup, 0> {
727	OutIter operator()(Func /* f */, const Tup& /* t */, OutIter out) const {
728	return out;
729	}
730	};
731	};
732
733	// Successively invokes 'f(element)' on each element of the tuple 't',
734	// appending each result to the 'out' iterator. Returns the final value
735	// of 'out'.
736	template <typename Tuple, typename Func, typename OutIter>
737	OutIter TransformTupleValues(Func f, const Tuple& t, OutIter out) {
738	return TransformTupleValuesHelper<Tuple, Func, OutIter>::Run(f, t, out);
739	}
740
741	// Implements _, a matcher that matches any value of any
742	// type. This is a polymorphic matcher, so we need a template type
743	// conversion operator to make it appearing as a Matcher<T> for any
744	// type T.
745	class AnythingMatcher {
746	public:
747	using is_gtest_matcher = void;
748
749	template <typename T>
750	bool MatchAndExplain(const T& /* x */, std::ostream* /* listener */) const {
751	return true;
752	}
753	void DescribeTo(std::ostream* os) const { *os << "is anything"; }
754	void DescribeNegationTo(::std::ostream* os) const {
755	// This is mostly for completeness' sake, as it's not very useful
756	// to write Not(A<bool>()). However we cannot completely rule out
757	// such a possibility, and it doesn't hurt to be prepared.
758	*os << "never matches";
759	}
760	};
761
762	// Implements the polymorphic IsNull() matcher, which matches any raw or smart
763	// pointer that is NULL.
764	class IsNullMatcher {
765	public:
766	template <typename Pointer>
767	bool MatchAndExplain(const Pointer& p,
768	MatchResultListener* /* listener */) const {
769	return p == nullptr;
770	}
771
772	void DescribeTo(::std::ostream* os) const { *os << "is NULL"; }
773	void DescribeNegationTo(::std::ostream* os) const { *os << "isn't NULL"; }
774	};
775
776	// Implements the polymorphic NotNull() matcher, which matches any raw or smart
777	// pointer that is not NULL.
778	class NotNullMatcher {
779	public:
780	template <typename Pointer>
781	bool MatchAndExplain(const Pointer& p,
782	MatchResultListener* /* listener */) const {
783	return p != nullptr;
784	}
785
786	void DescribeTo(::std::ostream* os) const { *os << "isn't NULL"; }
787	void DescribeNegationTo(::std::ostream* os) const { *os << "is NULL"; }
788	};
789
790	// Ref(variable) matches any argument that is a reference to
791	// 'variable'. This matcher is polymorphic as it can match any
792	// super type of the type of 'variable'.
793	//
794	// The RefMatcher template class implements Ref(variable). It can
795	// only be instantiated with a reference type. This prevents a user
796	// from mistakenly using Ref(x) to match a non-reference function
797	// argument. For example, the following will righteously cause a
798	// compiler error:
799	//
800	// int n;
801	// Matcher<int> m1 = Ref(n); // This won't compile.
802	// Matcher<int&> m2 = Ref(n); // This will compile.
803	template <typename T>
804	class RefMatcher;
805
806	template <typename T>
807	class RefMatcher<T&> {
808	// Google Mock is a generic framework and thus needs to support
809	// mocking any function types, including those that take non-const
810	// reference arguments. Therefore the template parameter T (and
811	// Super below) can be instantiated to either a const type or a
812	// non-const type.
813	public:
814	// RefMatcher() takes a T& instead of const T&, as we want the
815	// compiler to catch using Ref(const_value) as a matcher for a
816	// non-const reference.
817	explicit RefMatcher(T& x) : object_(x) {} // NOLINT
818
819	template <typename Super>
820	operator Matcher<Super&>() const {
821	// By passing object_ (type T&) to Impl(), which expects a Super&,
822	// we make sure that Super is a super type of T. In particular,
823	// this catches using Ref(const_value) as a matcher for a
824	// non-const reference, as you cannot implicitly convert a const
825	// reference to a non-const reference.
826	return MakeMatcher(new Impl<Super>(object_));
827	}
828
829	private:
830	template <typename Super>
831	class Impl : public MatcherInterface<Super&> {
832	public:
833	explicit Impl(Super& x) : object_(x) {} // NOLINT
834
835	// MatchAndExplain() takes a Super& (as opposed to const Super&)
836	// in order to match the interface MatcherInterface<Super&>.
837	bool MatchAndExplain(Super& x,
838	MatchResultListener* listener) const override {
839	*listener << "which is located @" << static_cast<const void*>(&x);
840	return &x == &object_;
841	}
842
843	void DescribeTo(::std::ostream* os) const override {
844	*os << "references the variable ";
845	UniversalPrinter<Super&>::Print(object_, os);
846	}
847
848	void DescribeNegationTo(::std::ostream* os) const override {
849	*os << "does not reference the variable ";
850	UniversalPrinter<Super&>::Print(object_, os);
851	}
852
853	private:
854	const Super& object_;
855	};
856
857	T& object_;
858	};
859
860	// Polymorphic helper functions for narrow and wide string matchers.
861	inline bool CaseInsensitiveCStringEquals(const char* lhs, const char* rhs) {
862	return String::CaseInsensitiveCStringEquals(lhs, rhs);
863	}
864
865	inline bool CaseInsensitiveCStringEquals(const wchar_t* lhs,
866	const wchar_t* rhs) {
867	return String::CaseInsensitiveWideCStringEquals(lhs, rhs);
868	}
869
870	// String comparison for narrow or wide strings that can have embedded NUL
871	// characters.
872	template <typename StringType>
873	bool CaseInsensitiveStringEquals(const StringType& s1, const StringType& s2) {
874	// Are the heads equal?
875	if (!CaseInsensitiveCStringEquals(s1.c_str(), s2.c_str())) {
876	return false;
877	}
878
879	// Skip the equal heads.
880	const typename StringType::value_type nul = 0;
881	const size_t i1 = s1.find(nul), i2 = s2.find(nul);
882
883	// Are we at the end of either s1 or s2?
884	if (i1 == StringType::npos || i2 == StringType::npos) {
885	return i1 == i2;
886	}
887
888	// Are the tails equal?
889	return CaseInsensitiveStringEquals(s1.substr(i1 + 1), s2.substr(i2 + 1));
890	}
891
892	// String matchers.
893
894	// Implements equality-based string matchers like StrEq, StrCaseNe, and etc.
895	template <typename StringType>
896	class StrEqualityMatcher {
897	public:
898	StrEqualityMatcher(StringType str, bool expect_eq, bool case_sensitive)
899	: string_(std::move(str)),
900	expect_eq_(expect_eq),
901	case_sensitive_(case_sensitive) {}
902
903	#if GTEST_INTERNAL_HAS_STRING_VIEW
904	bool MatchAndExplain(const internal::StringView& s,
905	MatchResultListener* listener) const {
906	// This should fail to compile if StringView is used with wide
907	// strings.
908	const StringType& str = std::string(s);
909	return MatchAndExplain(str, listener);
910	}
911	#endif // GTEST_INTERNAL_HAS_STRING_VIEW
912
913	// Accepts pointer types, particularly:
914	// const char*
915	// char*
916	// const wchar_t*
917	// wchar_t*
918	template <typename CharType>
919	bool MatchAndExplain(CharType* s, MatchResultListener* listener) const {
920	if (s == nullptr) {
921	return !expect_eq_;
922	}
923	return MatchAndExplain(StringType(s), listener);
924	}
925
926	// Matches anything that can convert to StringType.
927	//
928	// This is a template, not just a plain function with const StringType&,
929	// because StringView has some interfering non-explicit constructors.
930	template <typename MatcheeStringType>
931	bool MatchAndExplain(const MatcheeStringType& s,
932	MatchResultListener* /* listener */) const {
933	const StringType s2(s);
934	const bool eq = case_sensitive_ ? s2 == string_
935	: CaseInsensitiveStringEquals(s2, string_);
936	return expect_eq_ == eq;
937	}
938
939	void DescribeTo(::std::ostream* os) const {
940	DescribeToHelper(expect_eq: expect_eq_, os);
941	}
942
943	void DescribeNegationTo(::std::ostream* os) const {
944	DescribeToHelper(expect_eq: !expect_eq_, os);
945	}
946
947	private:
948	void DescribeToHelper(bool expect_eq, ::std::ostream* os) const {
949	*os << (expect_eq ? "is " : "isn't ");
950	*os << "equal to ";
951	if (!case_sensitive_) {
952	*os << "(ignoring case) ";
953	}
954	UniversalPrint(string_, os);
955	}
956
957	const StringType string_;
958	const bool expect_eq_;
959	const bool case_sensitive_;
960	};
961
962	// Implements the polymorphic HasSubstr(substring) matcher, which
963	// can be used as a Matcher<T> as long as T can be converted to a
964	// string.
965	template <typename StringType>
966	class HasSubstrMatcher {
967	public:
968	explicit HasSubstrMatcher(const StringType& substring)
969	: substring_(substring) {}
970
971	#if GTEST_INTERNAL_HAS_STRING_VIEW
972	bool MatchAndExplain(const internal::StringView& s,
973	MatchResultListener* listener) const {
974	// This should fail to compile if StringView is used with wide
975	// strings.
976	const StringType& str = std::string(s);
977	return MatchAndExplain(str, listener);
978	}
979	#endif // GTEST_INTERNAL_HAS_STRING_VIEW
980
981	// Accepts pointer types, particularly:
982	// const char*
983	// char*
984	// const wchar_t*
985	// wchar_t*
986	template <typename CharType>
987	bool MatchAndExplain(CharType* s, MatchResultListener* listener) const {
988	return s != nullptr && MatchAndExplain(StringType(s), listener);
989	}
990
991	// Matches anything that can convert to StringType.
992	//
993	// This is a template, not just a plain function with const StringType&,
994	// because StringView has some interfering non-explicit constructors.
995	template <typename MatcheeStringType>
996	bool MatchAndExplain(const MatcheeStringType& s,
997	MatchResultListener* /* listener */) const {
998	return StringType(s).find(substring_) != StringType::npos;
999	}
1000
1001	// Describes what this matcher matches.
1002	void DescribeTo(::std::ostream* os) const {
1003	*os << "has substring ";
1004	UniversalPrint(substring_, os);
1005	}
1006
1007	void DescribeNegationTo(::std::ostream* os) const {
1008	*os << "has no substring ";
1009	UniversalPrint(substring_, os);
1010	}
1011
1012	private:
1013	const StringType substring_;
1014	};
1015
1016	// Implements the polymorphic StartsWith(substring) matcher, which
1017	// can be used as a Matcher<T> as long as T can be converted to a
1018	// string.
1019	template <typename StringType>
1020	class StartsWithMatcher {
1021	public:
1022	explicit StartsWithMatcher(const StringType& prefix) : prefix_(prefix) {}
1023
1024	#if GTEST_INTERNAL_HAS_STRING_VIEW
1025	bool MatchAndExplain(const internal::StringView& s,
1026	MatchResultListener* listener) const {
1027	// This should fail to compile if StringView is used with wide
1028	// strings.
1029	const StringType& str = std::string(s);
1030	return MatchAndExplain(str, listener);
1031	}
1032	#endif // GTEST_INTERNAL_HAS_STRING_VIEW
1033
1034	// Accepts pointer types, particularly:
1035	// const char*
1036	// char*
1037	// const wchar_t*
1038	// wchar_t*
1039	template <typename CharType>
1040	bool MatchAndExplain(CharType* s, MatchResultListener* listener) const {
1041	return s != nullptr && MatchAndExplain(StringType(s), listener);
1042	}
1043
1044	// Matches anything that can convert to StringType.
1045	//
1046	// This is a template, not just a plain function with const StringType&,
1047	// because StringView has some interfering non-explicit constructors.
1048	template <typename MatcheeStringType>
1049	bool MatchAndExplain(const MatcheeStringType& s,
1050	MatchResultListener* /* listener */) const {
1051	const StringType& s2(s);
1052	return s2.length() >= prefix_.length() &&
1053	s2.substr(0, prefix_.length()) == prefix_;
1054	}
1055
1056	void DescribeTo(::std::ostream* os) const {
1057	*os << "starts with ";
1058	UniversalPrint(prefix_, os);
1059	}
1060
1061	void DescribeNegationTo(::std::ostream* os) const {
1062	*os << "doesn't start with ";
1063	UniversalPrint(prefix_, os);
1064	}
1065
1066	private:
1067	const StringType prefix_;
1068	};
1069
1070	// Implements the polymorphic EndsWith(substring) matcher, which
1071	// can be used as a Matcher<T> as long as T can be converted to a
1072	// string.
1073	template <typename StringType>
1074	class EndsWithMatcher {
1075	public:
1076	explicit EndsWithMatcher(const StringType& suffix) : suffix_(suffix) {}
1077
1078	#if GTEST_INTERNAL_HAS_STRING_VIEW
1079	bool MatchAndExplain(const internal::StringView& s,
1080	MatchResultListener* listener) const {
1081	// This should fail to compile if StringView is used with wide
1082	// strings.
1083	const StringType& str = std::string(s);
1084	return MatchAndExplain(str, listener);
1085	}
1086	#endif // GTEST_INTERNAL_HAS_STRING_VIEW
1087
1088	// Accepts pointer types, particularly:
1089	// const char*
1090	// char*
1091	// const wchar_t*
1092	// wchar_t*
1093	template <typename CharType>
1094	bool MatchAndExplain(CharType* s, MatchResultListener* listener) const {
1095	return s != nullptr && MatchAndExplain(StringType(s), listener);
1096	}
1097
1098	// Matches anything that can convert to StringType.
1099	//
1100	// This is a template, not just a plain function with const StringType&,
1101	// because StringView has some interfering non-explicit constructors.
1102	template <typename MatcheeStringType>
1103	bool MatchAndExplain(const MatcheeStringType& s,
1104	MatchResultListener* /* listener */) const {
1105	const StringType& s2(s);
1106	return s2.length() >= suffix_.length() &&
1107	s2.substr(s2.length() - suffix_.length()) == suffix_;
1108	}
1109
1110	void DescribeTo(::std::ostream* os) const {
1111	*os << "ends with ";
1112	UniversalPrint(suffix_, os);
1113	}
1114
1115	void DescribeNegationTo(::std::ostream* os) const {
1116	*os << "doesn't end with ";
1117	UniversalPrint(suffix_, os);
1118	}
1119
1120	private:
1121	const StringType suffix_;
1122	};
1123
1124	// Implements the polymorphic WhenBase64Unescaped(matcher) matcher, which can be
1125	// used as a Matcher<T> as long as T can be converted to a string.
1126	class WhenBase64UnescapedMatcher {
1127	public:
1128	using is_gtest_matcher = void;
1129
1130	explicit WhenBase64UnescapedMatcher(
1131	const Matcher<const std::string&>& internal_matcher)
1132	: internal_matcher_(internal_matcher) {}
1133
1134	// Matches anything that can convert to std::string.
1135	template <typename MatcheeStringType>
1136	bool MatchAndExplain(const MatcheeStringType& s,
1137	MatchResultListener* listener) const {
1138	const std::string s2(s); // NOLINT (needed for working with string_view).
1139	std::string unescaped;
1140	if (!internal::Base64Unescape(encoded: s2, decoded: &unescaped)) {
1141	if (listener != nullptr) {
1142	*listener << "is not a valid base64 escaped string";
1143	}
1144	return false;
1145	}
1146	return MatchPrintAndExplain(value&: unescaped, matcher: internal_matcher_, listener);
1147	}
1148
1149	void DescribeTo(::std::ostream* os) const {
1150	*os << "matches after Base64Unescape ";
1151	internal_matcher_.DescribeTo(os);
1152	}
1153
1154	void DescribeNegationTo(::std::ostream* os) const {
1155	*os << "does not match after Base64Unescape ";
1156	internal_matcher_.DescribeTo(os);
1157	}
1158
1159	private:
1160	const Matcher<const std::string&> internal_matcher_;
1161	};
1162
1163	// Implements a matcher that compares the two fields of a 2-tuple
1164	// using one of the ==, <=, <, etc, operators. The two fields being
1165	// compared don't have to have the same type.
1166	//
1167	// The matcher defined here is polymorphic (for example, Eq() can be
1168	// used to match a std::tuple<int, short>, a std::tuple<const long&, double>,
1169	// etc). Therefore we use a template type conversion operator in the
1170	// implementation.
1171	template <typename D, typename Op>
1172	class PairMatchBase {
1173	public:
1174	template <typename T1, typename T2>
1175	operator Matcher<::std::tuple<T1, T2>>() const {
1176	return Matcher<::std::tuple<T1, T2>>(new Impl<const ::std::tuple<T1, T2>&>);
1177	}
1178	template <typename T1, typename T2>
1179	operator Matcher<const ::std::tuple<T1, T2>&>() const {
1180	return MakeMatcher(new Impl<const ::std::tuple<T1, T2>&>);
1181	}
1182
1183	private:
1184	static ::std::ostream& GetDesc(::std::ostream& os) { // NOLINT
1185	return os << D::Desc();
1186	}
1187
1188	template <typename Tuple>
1189	class Impl : public MatcherInterface<Tuple> {
1190	public:
1191	bool MatchAndExplain(Tuple args,
1192	MatchResultListener* /* listener */) const override {
1193	return Op()(::std::get<0>(args), ::std::get<1>(args));
1194	}
1195	void DescribeTo(::std::ostream* os) const override {
1196	*os << "are " << GetDesc;
1197	}
1198	void DescribeNegationTo(::std::ostream* os) const override {
1199	*os << "aren't " << GetDesc;
1200	}
1201	};
1202	};
1203
1204	class Eq2Matcher : public PairMatchBase<Eq2Matcher, std::equal_to<>> {
1205	public:
1206	static const char* Desc() { return "an equal pair"; }
1207	};
1208	class Ne2Matcher : public PairMatchBase<Ne2Matcher, std::not_equal_to<>> {
1209	public:
1210	static const char* Desc() { return "an unequal pair"; }
1211	};
1212	class Lt2Matcher : public PairMatchBase<Lt2Matcher, std::less<>> {
1213	public:
1214	static const char* Desc() { return "a pair where the first < the second"; }
1215	};
1216	class Gt2Matcher : public PairMatchBase<Gt2Matcher, std::greater<>> {
1217	public:
1218	static const char* Desc() { return "a pair where the first > the second"; }
1219	};
1220	class Le2Matcher : public PairMatchBase<Le2Matcher, std::less_equal<>> {
1221	public:
1222	static const char* Desc() { return "a pair where the first <= the second"; }
1223	};
1224	class Ge2Matcher : public PairMatchBase<Ge2Matcher, std::greater_equal<>> {
1225	public:
1226	static const char* Desc() { return "a pair where the first >= the second"; }
1227	};
1228
1229	// Implements the Not(...) matcher for a particular argument type T.
1230	// We do not nest it inside the NotMatcher class template, as that
1231	// will prevent different instantiations of NotMatcher from sharing
1232	// the same NotMatcherImpl<T> class.
1233	template <typename T>
1234	class NotMatcherImpl : public MatcherInterface<const T&> {
1235	public:
1236	explicit NotMatcherImpl(const Matcher<T>& matcher) : matcher_(matcher) {}
1237
1238	bool MatchAndExplain(const T& x,
1239	MatchResultListener* listener) const override {
1240	return !matcher_.MatchAndExplain(x, listener);
1241	}
1242
1243	void DescribeTo(::std::ostream* os) const override {
1244	matcher_.DescribeNegationTo(os);
1245	}
1246
1247	void DescribeNegationTo(::std::ostream* os) const override {
1248	matcher_.DescribeTo(os);
1249	}
1250
1251	private:
1252	const Matcher<T> matcher_;
1253	};
1254
1255	// Implements the Not(m) matcher, which matches a value that doesn't
1256	// match matcher m.
1257	template <typename InnerMatcher>
1258	class NotMatcher {
1259	public:
1260	explicit NotMatcher(InnerMatcher matcher) : matcher_(matcher) {}
1261
1262	// This template type conversion operator allows Not(m) to be used
1263	// to match any type m can match.
1264	template <typename T>
1265	operator Matcher<T>() const {
1266	return Matcher<T>(new NotMatcherImpl<T>(SafeMatcherCast<T>(matcher_)));
1267	}
1268
1269	private:
1270	InnerMatcher matcher_;
1271	};
1272
1273	// Implements the AllOf(m1, m2) matcher for a particular argument type
1274	// T. We do not nest it inside the BothOfMatcher class template, as
1275	// that will prevent different instantiations of BothOfMatcher from
1276	// sharing the same BothOfMatcherImpl<T> class.
1277	template <typename T>
1278	class AllOfMatcherImpl : public MatcherInterface<const T&> {
1279	public:
1280	explicit AllOfMatcherImpl(std::vector<Matcher<T>> matchers)
1281	: matchers_(std::move(matchers)) {}
1282
1283	void DescribeTo(::std::ostream* os) const override {
1284	*os << "(";
1285	for (size_t i = 0; i < matchers_.size(); ++i) {
1286	if (i != 0) *os << ") and (";
1287	matchers_[i].DescribeTo(os);
1288	}
1289	*os << ")";
1290	}
1291
1292	void DescribeNegationTo(::std::ostream* os) const override {
1293	*os << "(";
1294	for (size_t i = 0; i < matchers_.size(); ++i) {
1295	if (i != 0) *os << ") or (";
1296	matchers_[i].DescribeNegationTo(os);
1297	}
1298	*os << ")";
1299	}
1300
1301	bool MatchAndExplain(const T& x,
1302	MatchResultListener* listener) const override {
1303	// If either matcher1_ or matcher2_ doesn't match x, we only need
1304	// to explain why one of them fails.
1305	std::string all_match_result;
1306
1307	for (size_t i = 0; i < matchers_.size(); ++i) {
1308	StringMatchResultListener slistener;
1309	if (matchers_[i].MatchAndExplain(x, &slistener)) {
1310	if (all_match_result.empty()) {
1311	all_match_result = slistener.str();
1312	} else {
1313	std::string result = slistener.str();
1314	if (!result.empty()) {
1315	all_match_result += ", and ";
1316	all_match_result += result;
1317	}
1318	}
1319	} else {
1320	*listener << slistener.str();
1321	return false;
1322	}
1323	}
1324
1325	// Otherwise we need to explain why *both* of them match.
1326	*listener << all_match_result;
1327	return true;
1328	}
1329
1330	private:
1331	const std::vector<Matcher<T>> matchers_;
1332	};
1333
1334	// VariadicMatcher is used for the variadic implementation of
1335	// AllOf(m_1, m_2, ...) and AnyOf(m_1, m_2, ...).
1336	// CombiningMatcher<T> is used to recursively combine the provided matchers
1337	// (of type Args...).
1338	template <template <typename T> class CombiningMatcher, typename... Args>
1339	class VariadicMatcher {
1340	public:
1341	VariadicMatcher(const Args&... matchers) // NOLINT
1342	: matchers_(matchers...) {
1343	static_assert(sizeof...(Args) > 0, "Must have at least one matcher.");
1344	}
1345
1346	VariadicMatcher(const VariadicMatcher&) = default;
1347	VariadicMatcher& operator=(const VariadicMatcher&) = delete;
1348
1349	// This template type conversion operator allows an
1350	// VariadicMatcher<Matcher1, Matcher2...> object to match any type that
1351	// all of the provided matchers (Matcher1, Matcher2, ...) can match.
1352	template <typename T>
1353	operator Matcher<T>() const {
1354	std::vector<Matcher<T>> values;
1355	CreateVariadicMatcher<T>(&values, std::integral_constant<size_t, 0>());
1356	return Matcher<T>(new CombiningMatcher<T>(std::move(values)));
1357	}
1358
1359	private:
1360	template <typename T, size_t I>
1361	void CreateVariadicMatcher(std::vector<Matcher<T>>* values,
1362	std::integral_constant<size_t, I>) const {
1363	values->push_back(SafeMatcherCast<T>(std::get<I>(matchers_)));
1364	CreateVariadicMatcher<T>(values, std::integral_constant<size_t, I + 1>());
1365	}
1366
1367	template <typename T>
1368	void CreateVariadicMatcher(
1369	std::vector<Matcher<T>>*,
1370	std::integral_constant<size_t, sizeof...(Args)>) const {}
1371
1372	std::tuple<Args...> matchers_;
1373	};
1374
1375	template <typename... Args>
1376	using AllOfMatcher = VariadicMatcher<AllOfMatcherImpl, Args...>;
1377
1378	// Implements the AnyOf(m1, m2) matcher for a particular argument type
1379	// T. We do not nest it inside the AnyOfMatcher class template, as
1380	// that will prevent different instantiations of AnyOfMatcher from
1381	// sharing the same EitherOfMatcherImpl<T> class.
1382	template <typename T>
1383	class AnyOfMatcherImpl : public MatcherInterface<const T&> {
1384	public:
1385	explicit AnyOfMatcherImpl(std::vector<Matcher<T>> matchers)
1386	: matchers_(std::move(matchers)) {}
1387
1388	void DescribeTo(::std::ostream* os) const override {
1389	*os << "(";
1390	for (size_t i = 0; i < matchers_.size(); ++i) {
1391	if (i != 0) *os << ") or (";
1392	matchers_[i].DescribeTo(os);
1393	}
1394	*os << ")";
1395	}
1396
1397	void DescribeNegationTo(::std::ostream* os) const override {
1398	*os << "(";
1399	for (size_t i = 0; i < matchers_.size(); ++i) {
1400	if (i != 0) *os << ") and (";
1401	matchers_[i].DescribeNegationTo(os);
1402	}
1403	*os << ")";
1404	}
1405
1406	bool MatchAndExplain(const T& x,
1407	MatchResultListener* listener) const override {
1408	std::string no_match_result;
1409
1410	// If either matcher1_ or matcher2_ matches x, we just need to
1411	// explain why *one* of them matches.
1412	for (size_t i = 0; i < matchers_.size(); ++i) {
1413	StringMatchResultListener slistener;
1414	if (matchers_[i].MatchAndExplain(x, &slistener)) {
1415	*listener << slistener.str();
1416	return true;
1417	} else {
1418	if (no_match_result.empty()) {
1419	no_match_result = slistener.str();
1420	} else {
1421	std::string result = slistener.str();
1422	if (!result.empty()) {
1423	no_match_result += ", and ";
1424	no_match_result += result;
1425	}
1426	}
1427	}
1428	}
1429
1430	// Otherwise we need to explain why *both* of them fail.
1431	*listener << no_match_result;
1432	return false;
1433	}
1434
1435	private:
1436	const std::vector<Matcher<T>> matchers_;
1437	};
1438
1439	// AnyOfMatcher is used for the variadic implementation of AnyOf(m_1, m_2, ...).
1440	template <typename... Args>
1441	using AnyOfMatcher = VariadicMatcher<AnyOfMatcherImpl, Args...>;
1442
1443	// ConditionalMatcher is the implementation of Conditional(cond, m1, m2)
1444	template <typename MatcherTrue, typename MatcherFalse>
1445	class ConditionalMatcher {
1446	public:
1447	ConditionalMatcher(bool condition, MatcherTrue matcher_true,
1448	MatcherFalse matcher_false)
1449	: condition_(condition),
1450	matcher_true_(std::move(matcher_true)),
1451	matcher_false_(std::move(matcher_false)) {}
1452
1453	template <typename T>
1454	operator Matcher<T>() const { // NOLINT(runtime/explicit)
1455	return condition_ ? SafeMatcherCast<T>(matcher_true_)
1456	: SafeMatcherCast<T>(matcher_false_);
1457	}
1458
1459	private:
1460	bool condition_;
1461	MatcherTrue matcher_true_;
1462	MatcherFalse matcher_false_;
1463	};
1464
1465	// Wrapper for implementation of Any/AllOfArray().
1466	template <template <class> class MatcherImpl, typename T>
1467	class SomeOfArrayMatcher {
1468	public:
1469	// Constructs the matcher from a sequence of element values or
1470	// element matchers.
1471	template <typename Iter>
1472	SomeOfArrayMatcher(Iter first, Iter last) : matchers_(first, last) {}
1473
1474	template <typename U>
1475	operator Matcher<U>() const { // NOLINT
1476	using RawU = typename std::decay<U>::type;
1477	std::vector<Matcher<RawU>> matchers;
1478	matchers.reserve(matchers_.size());
1479	for (const auto& matcher : matchers_) {
1480	matchers.push_back(MatcherCast<RawU>(matcher));
1481	}
1482	return Matcher<U>(new MatcherImpl<RawU>(std::move(matchers)));
1483	}
1484
1485	private:
1486	const ::std::vector<T> matchers_;
1487	};
1488
1489	template <typename T>
1490	using AllOfArrayMatcher = SomeOfArrayMatcher<AllOfMatcherImpl, T>;
1491
1492	template <typename T>
1493	using AnyOfArrayMatcher = SomeOfArrayMatcher<AnyOfMatcherImpl, T>;
1494
1495	// Used for implementing Truly(pred), which turns a predicate into a
1496	// matcher.
1497	template <typename Predicate>
1498	class TrulyMatcher {
1499	public:
1500	explicit TrulyMatcher(Predicate pred) : predicate_(pred) {}
1501
1502	// This method template allows Truly(pred) to be used as a matcher
1503	// for type T where T is the argument type of predicate 'pred'. The
1504	// argument is passed by reference as the predicate may be
1505	// interested in the address of the argument.
1506	template <typename T>
1507	bool MatchAndExplain(T& x, // NOLINT
1508	MatchResultListener* listener) const {
1509	// Without the if-statement, MSVC sometimes warns about converting
1510	// a value to bool (warning 4800).
1511	//
1512	// We cannot write 'return !!predicate_(x);' as that doesn't work
1513	// when predicate_(x) returns a class convertible to bool but
1514	// having no operator!().
1515	if (predicate_(x)) return true;
1516	*listener << "didn't satisfy the given predicate";
1517	return false;
1518	}
1519
1520	void DescribeTo(::std::ostream* os) const {
1521	*os << "satisfies the given predicate";
1522	}
1523
1524	void DescribeNegationTo(::std::ostream* os) const {
1525	*os << "doesn't satisfy the given predicate";
1526	}
1527
1528	private:
1529	Predicate predicate_;
1530	};
1531
1532	// Used for implementing Matches(matcher), which turns a matcher into
1533	// a predicate.
1534	template <typename M>
1535	class MatcherAsPredicate {
1536	public:
1537	explicit MatcherAsPredicate(M matcher) : matcher_(matcher) {}
1538
1539	// This template operator() allows Matches(m) to be used as a
1540	// predicate on type T where m is a matcher on type T.
1541	//
1542	// The argument x is passed by reference instead of by value, as
1543	// some matcher may be interested in its address (e.g. as in
1544	// Matches(Ref(n))(x)).
1545	template <typename T>
1546	bool operator()(const T& x) const {
1547	// We let matcher_ commit to a particular type here instead of
1548	// when the MatcherAsPredicate object was constructed. This
1549	// allows us to write Matches(m) where m is a polymorphic matcher
1550	// (e.g. Eq(5)).
1551	//
1552	// If we write Matcher<T>(matcher_).Matches(x) here, it won't
1553	// compile when matcher_ has type Matcher<const T&>; if we write
1554	// Matcher<const T&>(matcher_).Matches(x) here, it won't compile
1555	// when matcher_ has type Matcher<T>; if we just write
1556	// matcher_.Matches(x), it won't compile when matcher_ is
1557	// polymorphic, e.g. Eq(5).
1558	//
1559	// MatcherCast<const T&>() is necessary for making the code work
1560	// in all of the above situations.
1561	return MatcherCast<const T&>(matcher_).Matches(x);
1562	}
1563
1564	private:
1565	M matcher_;
1566	};
1567
1568	// For implementing ASSERT_THAT() and EXPECT_THAT(). The template
1569	// argument M must be a type that can be converted to a matcher.
1570	template <typename M>
1571	class PredicateFormatterFromMatcher {
1572	public:
1573	explicit PredicateFormatterFromMatcher(M m) : matcher_(std::move(m)) {}
1574
1575	// This template () operator allows a PredicateFormatterFromMatcher
1576	// object to act as a predicate-formatter suitable for using with
1577	// Google Test's EXPECT_PRED_FORMAT1() macro.
1578	template <typename T>
1579	AssertionResult operator()(const char* value_text, const T& x) const {
1580	// We convert matcher_ to a Matcher<const T&> *now* instead of
1581	// when the PredicateFormatterFromMatcher object was constructed,
1582	// as matcher_ may be polymorphic (e.g. NotNull()) and we won't
1583	// know which type to instantiate it to until we actually see the
1584	// type of x here.
1585	//
1586	// We write SafeMatcherCast<const T&>(matcher_) instead of
1587	// Matcher<const T&>(matcher_), as the latter won't compile when
1588	// matcher_ has type Matcher<T> (e.g. An<int>()).
1589	// We don't write MatcherCast<const T&> either, as that allows
1590	// potentially unsafe downcasting of the matcher argument.
1591	const Matcher<const T&> matcher = SafeMatcherCast<const T&>(matcher_);
1592
1593	// The expected path here is that the matcher should match (i.e. that most
1594	// tests pass) so optimize for this case.
1595	if (matcher.Matches(x)) {
1596	return AssertionSuccess();
1597	}
1598
1599	::std::stringstream ss;
1600	ss << "Value of: " << value_text << "\n"
1601	<< "Expected: ";
1602	matcher.DescribeTo(&ss);
1603
1604	// Rerun the matcher to "PrintAndExplain" the failure.
1605	StringMatchResultListener listener;
1606	if (MatchPrintAndExplain(x, matcher, &listener)) {
1607	ss << "\n The matcher failed on the initial attempt; but passed when "
1608	"rerun to generate the explanation.";
1609	}
1610	ss << "\n Actual: " << listener.str();
1611	return AssertionFailure() << ss.str();
1612	}
1613
1614	private:
1615	const M matcher_;
1616	};
1617
1618	// A helper function for converting a matcher to a predicate-formatter
1619	// without the user needing to explicitly write the type. This is
1620	// used for implementing ASSERT_THAT() and EXPECT_THAT().
1621	// Implementation detail: 'matcher' is received by-value to force decaying.
1622	template <typename M>
1623	inline PredicateFormatterFromMatcher<M> MakePredicateFormatterFromMatcher(
1624	M matcher) {
1625	return PredicateFormatterFromMatcher<M>(std::move(matcher));
1626	}
1627
1628	// Implements the polymorphic IsNan() matcher, which matches any floating type
1629	// value that is Nan.
1630	class IsNanMatcher {
1631	public:
1632	template <typename FloatType>
1633	bool MatchAndExplain(const FloatType& f,
1634	MatchResultListener* /* listener */) const {
1635	return (::std::isnan)(f);
1636	}
1637
1638	void DescribeTo(::std::ostream* os) const { *os << "is NaN"; }
1639	void DescribeNegationTo(::std::ostream* os) const { *os << "isn't NaN"; }
1640	};
1641
1642	// Implements the polymorphic floating point equality matcher, which matches
1643	// two float values using ULP-based approximation or, optionally, a
1644	// user-specified epsilon. The template is meant to be instantiated with
1645	// FloatType being either float or double.
1646	template <typename FloatType>
1647	class FloatingEqMatcher {
1648	public:
1649	// Constructor for FloatingEqMatcher.
1650	// The matcher's input will be compared with expected. The matcher treats two
1651	// NANs as equal if nan_eq_nan is true. Otherwise, under IEEE standards,
1652	// equality comparisons between NANs will always return false. We specify a
1653	// negative max_abs_error_ term to indicate that ULP-based approximation will
1654	// be used for comparison.
1655	FloatingEqMatcher(FloatType expected, bool nan_eq_nan)
1656	: expected_(expected), nan_eq_nan_(nan_eq_nan), max_abs_error_(-1) {}
1657
1658	// Constructor that supports a user-specified max_abs_error that will be used
1659	// for comparison instead of ULP-based approximation. The max absolute
1660	// should be non-negative.
1661	FloatingEqMatcher(FloatType expected, bool nan_eq_nan,
1662	FloatType max_abs_error)
1663	: expected_(expected),
1664	nan_eq_nan_(nan_eq_nan),
1665	max_abs_error_(max_abs_error) {
1666	GTEST_CHECK_(max_abs_error >= 0)
1667	<< ", where max_abs_error is" << max_abs_error;
1668	}
1669
1670	// Implements floating point equality matcher as a Matcher<T>.
1671	template <typename T>
1672	class Impl : public MatcherInterface<T> {
1673	public:
1674	Impl(FloatType expected, bool nan_eq_nan, FloatType max_abs_error)
1675	: expected_(expected),
1676	nan_eq_nan_(nan_eq_nan),
1677	max_abs_error_(max_abs_error) {}
1678
1679	bool MatchAndExplain(T value,
1680	MatchResultListener* listener) const override {
1681	const FloatingPoint<FloatType> actual(value), expected(expected_);
1682
1683	// Compares NaNs first, if nan_eq_nan_ is true.
1684	if (actual.is_nan() || expected.is_nan()) {
1685	if (actual.is_nan() && expected.is_nan()) {
1686	return nan_eq_nan_;
1687	}
1688	// One is nan; the other is not nan.
1689	return false;
1690	}
1691	if (HasMaxAbsError()) {
1692	// We perform an equality check so that inf will match inf, regardless
1693	// of error bounds. If the result of value - expected_ would result in
1694	// overflow or if either value is inf, the default result is infinity,
1695	// which should only match if max_abs_error_ is also infinity.
1696	if (value == expected_) {
1697	return true;
1698	}
1699
1700	const FloatType diff = value - expected_;
1701	if (::std::fabs(diff) <= max_abs_error_) {
1702	return true;
1703	}
1704
1705	if (listener->IsInterested()) {
1706	*listener << "which is " << diff << " from " << expected_;
1707	}
1708	return false;
1709	} else {
1710	return actual.AlmostEquals(expected);
1711	}
1712	}
1713
1714	void DescribeTo(::std::ostream* os) const override {
1715	// os->precision() returns the previously set precision, which we
1716	// store to restore the ostream to its original configuration
1717	// after outputting.
1718	const ::std::streamsize old_precision =
1719	os->precision(::std::numeric_limits<FloatType>::digits10 + 2);
1720	if (FloatingPoint<FloatType>(expected_).is_nan()) {
1721	if (nan_eq_nan_) {
1722	*os << "is NaN";
1723	} else {
1724	*os << "never matches";
1725	}
1726	} else {
1727	*os << "is approximately " << expected_;
1728	if (HasMaxAbsError()) {
1729	*os << " (absolute error <= " << max_abs_error_ << ")";
1730	}
1731	}
1732	os->precision(prec: old_precision);
1733	}
1734
1735	void DescribeNegationTo(::std::ostream* os) const override {
1736	// As before, get original precision.
1737	const ::std::streamsize old_precision =
1738	os->precision(::std::numeric_limits<FloatType>::digits10 + 2);
1739	if (FloatingPoint<FloatType>(expected_).is_nan()) {
1740	if (nan_eq_nan_) {
1741	*os << "isn't NaN";
1742	} else {
1743	*os << "is anything";
1744	}
1745	} else {
1746	*os << "isn't approximately " << expected_;
1747	if (HasMaxAbsError()) {
1748	*os << " (absolute error > " << max_abs_error_ << ")";
1749	}
1750	}
1751	// Restore original precision.
1752	os->precision(prec: old_precision);
1753	}
1754
1755	private:
1756	bool HasMaxAbsError() const { return max_abs_error_ >= 0; }
1757
1758	const FloatType expected_;
1759	const bool nan_eq_nan_;
1760	// max_abs_error will be used for value comparison when >= 0.
1761	const FloatType max_abs_error_;
1762	};
1763
1764	// The following 3 type conversion operators allow FloatEq(expected) and
1765	// NanSensitiveFloatEq(expected) to be used as a Matcher<float>, a
1766	// Matcher<const float&>, or a Matcher<float&>, but nothing else.
1767	operator Matcher<FloatType>() const {
1768	return MakeMatcher(
1769	new Impl<FloatType>(expected_, nan_eq_nan_, max_abs_error_));
1770	}
1771
1772	operator Matcher<const FloatType&>() const {
1773	return MakeMatcher(
1774	new Impl<const FloatType&>(expected_, nan_eq_nan_, max_abs_error_));
1775	}
1776
1777	operator Matcher<FloatType&>() const {
1778	return MakeMatcher(
1779	new Impl<FloatType&>(expected_, nan_eq_nan_, max_abs_error_));
1780	}
1781
1782	private:
1783	const FloatType expected_;
1784	const bool nan_eq_nan_;
1785	// max_abs_error will be used for value comparison when >= 0.
1786	const FloatType max_abs_error_;
1787	};
1788
1789	// A 2-tuple ("binary") wrapper around FloatingEqMatcher:
1790	// FloatingEq2Matcher() matches (x, y) by matching FloatingEqMatcher(x, false)
1791	// against y, and FloatingEq2Matcher(e) matches FloatingEqMatcher(x, false, e)
1792	// against y. The former implements "Eq", the latter "Near". At present, there
1793	// is no version that compares NaNs as equal.
1794	template <typename FloatType>
1795	class FloatingEq2Matcher {
1796	public:
1797	FloatingEq2Matcher() { Init(max_abs_error_val: -1, nan_eq_nan_val: false); }
1798
1799	explicit FloatingEq2Matcher(bool nan_eq_nan) { Init(max_abs_error_val: -1, nan_eq_nan_val: nan_eq_nan); }
1800
1801	explicit FloatingEq2Matcher(FloatType max_abs_error) {
1802	Init(max_abs_error_val: max_abs_error, nan_eq_nan_val: false);
1803	}
1804
1805	FloatingEq2Matcher(FloatType max_abs_error, bool nan_eq_nan) {
1806	Init(max_abs_error_val: max_abs_error, nan_eq_nan_val: nan_eq_nan);
1807	}
1808
1809	template <typename T1, typename T2>
1810	operator Matcher<::std::tuple<T1, T2>>() const {
1811	return MakeMatcher(
1812	new Impl<::std::tuple<T1, T2>>(max_abs_error_, nan_eq_nan_));
1813	}
1814	template <typename T1, typename T2>
1815	operator Matcher<const ::std::tuple<T1, T2>&>() const {
1816	return MakeMatcher(
1817	new Impl<const ::std::tuple<T1, T2>&>(max_abs_error_, nan_eq_nan_));
1818	}
1819
1820	private:
1821	static ::std::ostream& GetDesc(::std::ostream& os) { // NOLINT
1822	return os << "an almost-equal pair";
1823	}
1824
1825	template <typename Tuple>
1826	class Impl : public MatcherInterface<Tuple> {
1827	public:
1828	Impl(FloatType max_abs_error, bool nan_eq_nan)
1829	: max_abs_error_(max_abs_error), nan_eq_nan_(nan_eq_nan) {}
1830
1831	bool MatchAndExplain(Tuple args,
1832	MatchResultListener* listener) const override {
1833	if (max_abs_error_ == -1) {
1834	FloatingEqMatcher<FloatType> fm(::std::get<0>(args), nan_eq_nan_);
1835	return static_cast<Matcher<FloatType>>(fm).MatchAndExplain(
1836	::std::get<1>(args), listener);
1837	} else {
1838	FloatingEqMatcher<FloatType> fm(::std::get<0>(args), nan_eq_nan_,
1839	max_abs_error_);
1840	return static_cast<Matcher<FloatType>>(fm).MatchAndExplain(
1841	::std::get<1>(args), listener);
1842	}
1843	}
1844	void DescribeTo(::std::ostream* os) const override {
1845	*os << "are " << GetDesc;
1846	}
1847	void DescribeNegationTo(::std::ostream* os) const override {
1848	*os << "aren't " << GetDesc;
1849	}
1850
1851	private:
1852	FloatType max_abs_error_;
1853	const bool nan_eq_nan_;
1854	};
1855
1856	void Init(FloatType max_abs_error_val, bool nan_eq_nan_val) {
1857	max_abs_error_ = max_abs_error_val;
1858	nan_eq_nan_ = nan_eq_nan_val;
1859	}
1860	FloatType max_abs_error_;
1861	bool nan_eq_nan_;
1862	};
1863
1864	// Implements the Pointee(m) matcher for matching a pointer whose
1865	// pointee matches matcher m. The pointer can be either raw or smart.
1866	template <typename InnerMatcher>
1867	class PointeeMatcher {
1868	public:
1869	explicit PointeeMatcher(const InnerMatcher& matcher) : matcher_(matcher) {}
1870
1871	// This type conversion operator template allows Pointee(m) to be
1872	// used as a matcher for any pointer type whose pointee type is
1873	// compatible with the inner matcher, where type Pointer can be
1874	// either a raw pointer or a smart pointer.
1875	//
1876	// The reason we do this instead of relying on
1877	// MakePolymorphicMatcher() is that the latter is not flexible
1878	// enough for implementing the DescribeTo() method of Pointee().
1879	template <typename Pointer>
1880	operator Matcher<Pointer>() const {
1881	return Matcher<Pointer>(new Impl<const Pointer&>(matcher_));
1882	}
1883
1884	private:
1885	// The monomorphic implementation that works for a particular pointer type.
1886	template <typename Pointer>
1887	class Impl : public MatcherInterface<Pointer> {
1888	public:
1889	using Pointee =
1890	typename std::pointer_traits<GTEST_REMOVE_REFERENCE_AND_CONST_(
1891	Pointer)>::element_type;
1892
1893	explicit Impl(const InnerMatcher& matcher)
1894	: matcher_(MatcherCast<const Pointee&>(matcher)) {}
1895
1896	void DescribeTo(::std::ostream* os) const override {
1897	*os << "points to a value that ";
1898	matcher_.DescribeTo(os);
1899	}
1900
1901	void DescribeNegationTo(::std::ostream* os) const override {
1902	*os << "does not point to a value that ";
1903	matcher_.DescribeTo(os);
1904	}
1905
1906	bool MatchAndExplain(Pointer pointer,
1907	MatchResultListener* listener) const override {
1908	if (GetRawPointer(pointer) == nullptr) return false;
1909
1910	*listener << "which points to ";
1911	return MatchPrintAndExplain(*pointer, matcher_, listener);
1912	}
1913
1914	private:
1915	const Matcher<const Pointee&> matcher_;
1916	};
1917
1918	const InnerMatcher matcher_;
1919	};
1920
1921	// Implements the Pointer(m) matcher
1922	// Implements the Pointer(m) matcher for matching a pointer that matches matcher
1923	// m. The pointer can be either raw or smart, and will match `m` against the
1924	// raw pointer.
1925	template <typename InnerMatcher>
1926	class PointerMatcher {
1927	public:
1928	explicit PointerMatcher(const InnerMatcher& matcher) : matcher_(matcher) {}
1929
1930	// This type conversion operator template allows Pointer(m) to be
1931	// used as a matcher for any pointer type whose pointer type is
1932	// compatible with the inner matcher, where type PointerType can be
1933	// either a raw pointer or a smart pointer.
1934	//
1935	// The reason we do this instead of relying on
1936	// MakePolymorphicMatcher() is that the latter is not flexible
1937	// enough for implementing the DescribeTo() method of Pointer().
1938	template <typename PointerType>
1939	operator Matcher<PointerType>() const { // NOLINT
1940	return Matcher<PointerType>(new Impl<const PointerType&>(matcher_));
1941	}
1942
1943	private:
1944	// The monomorphic implementation that works for a particular pointer type.
1945	template <typename PointerType>
1946	class Impl : public MatcherInterface<PointerType> {
1947	public:
1948	using Pointer =
1949	const typename std::pointer_traits<GTEST_REMOVE_REFERENCE_AND_CONST_(
1950	PointerType)>::element_type*;
1951
1952	explicit Impl(const InnerMatcher& matcher)
1953	: matcher_(MatcherCast<Pointer>(matcher)) {}
1954
1955	void DescribeTo(::std::ostream* os) const override {
1956	*os << "is a pointer that ";
1957	matcher_.DescribeTo(os);
1958	}
1959
1960	void DescribeNegationTo(::std::ostream* os) const override {
1961	*os << "is not a pointer that ";
1962	matcher_.DescribeTo(os);
1963	}
1964
1965	bool MatchAndExplain(PointerType pointer,
1966	MatchResultListener* listener) const override {
1967	*listener << "which is a pointer that ";
1968	Pointer p = GetRawPointer(pointer);
1969	return MatchPrintAndExplain(p, matcher_, listener);
1970	}
1971
1972	private:
1973	Matcher<Pointer> matcher_;
1974	};
1975
1976	const InnerMatcher matcher_;
1977	};
1978
1979	#if GTEST_HAS_RTTI
1980	// Implements the WhenDynamicCastTo<T>(m) matcher that matches a pointer or
1981	// reference that matches inner_matcher when dynamic_cast<T> is applied.
1982	// The result of dynamic_cast<To> is forwarded to the inner matcher.
1983	// If To is a pointer and the cast fails, the inner matcher will receive NULL.
1984	// If To is a reference and the cast fails, this matcher returns false
1985	// immediately.
1986	template <typename To>
1987	class WhenDynamicCastToMatcherBase {
1988	public:
1989	explicit WhenDynamicCastToMatcherBase(const Matcher<To>& matcher)
1990	: matcher_(matcher) {}
1991
1992	void DescribeTo(::std::ostream* os) const {
1993	GetCastTypeDescription(os);
1994	matcher_.DescribeTo(os);
1995	}
1996
1997	void DescribeNegationTo(::std::ostream* os) const {
1998	GetCastTypeDescription(os);
1999	matcher_.DescribeNegationTo(os);
2000	}
2001
2002	protected:
2003	const Matcher<To> matcher_;
2004
2005	static std::string GetToName() { return GetTypeName<To>(); }
2006
2007	private:
2008	static void GetCastTypeDescription(::std::ostream* os) {
2009	*os << "when dynamic_cast to " << GetToName() << ", ";
2010	}
2011	};
2012
2013	// Primary template.
2014	// To is a pointer. Cast and forward the result.
2015	template <typename To>
2016	class WhenDynamicCastToMatcher : public WhenDynamicCastToMatcherBase<To> {
2017	public:
2018	explicit WhenDynamicCastToMatcher(const Matcher<To>& matcher)
2019	: WhenDynamicCastToMatcherBase<To>(matcher) {}
2020
2021	template <typename From>
2022	bool MatchAndExplain(From from, MatchResultListener* listener) const {
2023	To to = dynamic_cast<To>(from);
2024	return MatchPrintAndExplain(to, this->matcher_, listener);
2025	}
2026	};
2027
2028	// Specialize for references.
2029	// In this case we return false if the dynamic_cast fails.
2030	template <typename To>
2031	class WhenDynamicCastToMatcher<To&> : public WhenDynamicCastToMatcherBase<To&> {
2032	public:
2033	explicit WhenDynamicCastToMatcher(const Matcher<To&>& matcher)
2034	: WhenDynamicCastToMatcherBase<To&>(matcher) {}
2035
2036	template <typename From>
2037	bool MatchAndExplain(From& from, MatchResultListener* listener) const {
2038	// We don't want an std::bad_cast here, so do the cast with pointers.
2039	To* to = dynamic_cast<To*>(&from);
2040	if (to == nullptr) {
2041	*listener << "which cannot be dynamic_cast to " << this->GetToName();
2042	return false;
2043	}
2044	return MatchPrintAndExplain(*to, this->matcher_, listener);
2045	}
2046	};
2047	#endif // GTEST_HAS_RTTI
2048
2049	// Implements the Field() matcher for matching a field (i.e. member
2050	// variable) of an object.
2051	template <typename Class, typename FieldType>
2052	class FieldMatcher {
2053	public:
2054	FieldMatcher(FieldType Class::*field,
2055	const Matcher<const FieldType&>& matcher)
2056	: field_(field), matcher_(matcher), whose_field_("whose given field ") {}
2057
2058	FieldMatcher(const std::string& field_name, FieldType Class::*field,
2059	const Matcher<const FieldType&>& matcher)
2060	: field_(field),
2061	matcher_(matcher),
2062	whose_field_("whose field `" + field_name + "` ") {}
2063
2064	void DescribeTo(::std::ostream* os) const {
2065	*os << "is an object " << whose_field_;
2066	matcher_.DescribeTo(os);
2067	}
2068
2069	void DescribeNegationTo(::std::ostream* os) const {
2070	*os << "is an object " << whose_field_;
2071	matcher_.DescribeNegationTo(os);
2072	}
2073
2074	template <typename T>
2075	bool MatchAndExplain(const T& value, MatchResultListener* listener) const {
2076	// FIXME: The dispatch on std::is_pointer was introduced as a workaround for
2077	// a compiler bug, and can now be removed.
2078	return MatchAndExplainImpl(
2079	typename std::is_pointer<typename std::remove_const<T>::type>::type(),
2080	value, listener);
2081	}
2082
2083	private:
2084	bool MatchAndExplainImpl(std::false_type /* is_not_pointer */,
2085	const Class& obj,
2086	MatchResultListener* listener) const {
2087	*listener << whose_field_ << "is ";
2088	return MatchPrintAndExplain(obj.*field_, matcher_, listener);
2089	}
2090
2091	bool MatchAndExplainImpl(std::true_type /* is_pointer */, const Class* p,
2092	MatchResultListener* listener) const {
2093	if (p == nullptr) return false;
2094
2095	*listener << "which points to an object ";
2096	// Since *p has a field, it must be a class/struct/union type and
2097	// thus cannot be a pointer. Therefore we pass false_type() as
2098	// the first argument.
2099	return MatchAndExplainImpl(std::false_type(), *p, listener);
2100	}
2101
2102	const FieldType Class::*field_;
2103	const Matcher<const FieldType&> matcher_;
2104
2105	// Contains either "whose given field " if the name of the field is unknown
2106	// or "whose field `name_of_field` " if the name is known.
2107	const std::string whose_field_;
2108	};
2109
2110	// Implements the Property() matcher for matching a property
2111	// (i.e. return value of a getter method) of an object.
2112	//
2113	// Property is a const-qualified member function of Class returning
2114	// PropertyType.
2115	template <typename Class, typename PropertyType, typename Property>
2116	class PropertyMatcher {
2117	public:
2118	typedef const PropertyType& RefToConstProperty;
2119
2120	PropertyMatcher(Property property, const Matcher<RefToConstProperty>& matcher)
2121	: property_(property),
2122	matcher_(matcher),
2123	whose_property_("whose given property ") {}
2124
2125	PropertyMatcher(const std::string& property_name, Property property,
2126	const Matcher<RefToConstProperty>& matcher)
2127	: property_(property),
2128	matcher_(matcher),
2129	whose_property_("whose property `" + property_name + "` ") {}
2130
2131	void DescribeTo(::std::ostream* os) const {
2132	*os << "is an object " << whose_property_;
2133	matcher_.DescribeTo(os);
2134	}
2135
2136	void DescribeNegationTo(::std::ostream* os) const {
2137	*os << "is an object " << whose_property_;
2138	matcher_.DescribeNegationTo(os);
2139	}
2140
2141	template <typename T>
2142	bool MatchAndExplain(const T& value, MatchResultListener* listener) const {
2143	return MatchAndExplainImpl(
2144	typename std::is_pointer<typename std::remove_const<T>::type>::type(),
2145	value, listener);
2146	}
2147
2148	private:
2149	bool MatchAndExplainImpl(std::false_type /* is_not_pointer */,
2150	const Class& obj,
2151	MatchResultListener* listener) const {
2152	*listener << whose_property_ << "is ";
2153	// Cannot pass the return value (for example, int) to MatchPrintAndExplain,
2154	// which takes a non-const reference as argument.
2155	RefToConstProperty result = (obj.*property_)();
2156	return MatchPrintAndExplain(result, matcher_, listener);
2157	}
2158
2159	bool MatchAndExplainImpl(std::true_type /* is_pointer */, const Class* p,
2160	MatchResultListener* listener) const {
2161	if (p == nullptr) return false;
2162
2163	*listener << "which points to an object ";
2164	// Since *p has a property method, it must be a class/struct/union
2165	// type and thus cannot be a pointer. Therefore we pass
2166	// false_type() as the first argument.
2167	return MatchAndExplainImpl(std::false_type(), *p, listener);
2168	}
2169
2170	Property property_;
2171	const Matcher<RefToConstProperty> matcher_;
2172
2173	// Contains either "whose given property " if the name of the property is
2174	// unknown or "whose property `name_of_property` " if the name is known.
2175	const std::string whose_property_;
2176	};
2177
2178	// Type traits specifying various features of different functors for ResultOf.
2179	// The default template specifies features for functor objects.
2180	template <typename Functor>
2181	struct CallableTraits {
2182	typedef Functor StorageType;
2183
2184	static void CheckIsValid(Functor /* functor */) {}
2185
2186	template <typename T>
2187	static auto Invoke(Functor f, const T& arg) -> decltype(f(arg)) {
2188	return f(arg);
2189	}
2190	};
2191
2192	// Specialization for function pointers.
2193	template <typename ArgType, typename ResType>
2194	struct CallableTraits<ResType (*)(ArgType)> {
2195	typedef ResType ResultType;
2196	typedef ResType (*StorageType)(ArgType);
2197
2198	static void CheckIsValid(ResType (*f)(ArgType)) {
2199	GTEST_CHECK_(f != nullptr)
2200	<< "NULL function pointer is passed into ResultOf().";
2201	}
2202	template <typename T>
2203	static ResType Invoke(ResType (*f)(ArgType), T arg) {
2204	return (*f)(arg);
2205	}
2206	};
2207
2208	// Implements the ResultOf() matcher for matching a return value of a
2209	// unary function of an object.
2210	template <typename Callable, typename InnerMatcher>
2211	class ResultOfMatcher {
2212	public:
2213	ResultOfMatcher(Callable callable, InnerMatcher matcher)
2214	: ResultOfMatcher(/*result_description=*/"", std::move(callable),
2215	std::move(matcher)) {}
2216
2217	ResultOfMatcher(const std::string& result_description, Callable callable,
2218	InnerMatcher matcher)
2219	: result_description_(result_description),
2220	callable_(std::move(callable)),
2221	matcher_(std::move(matcher)) {
2222	CallableTraits<Callable>::CheckIsValid(callable_);
2223	}
2224
2225	template <typename T>
2226	operator Matcher<T>() const {
2227	return Matcher<T>(
2228	new Impl<const T&>(result_description_, callable_, matcher_));
2229	}
2230
2231	private:
2232	typedef typename CallableTraits<Callable>::StorageType CallableStorageType;
2233
2234	template <typename T>
2235	class Impl : public MatcherInterface<T> {
2236	using ResultType = decltype(CallableTraits<Callable>::template Invoke<T>(
2237	std::declval<CallableStorageType>(), std::declval<T>()));
2238
2239	public:
2240	template <typename M>
2241	Impl(const std::string& result_description,
2242	const CallableStorageType& callable, const M& matcher)
2243	: result_description_(result_description),
2244	callable_(callable),
2245	matcher_(MatcherCast<ResultType>(matcher)) {}
2246
2247	void DescribeTo(::std::ostream* os) const override {
2248	if (result_description_.empty()) {
2249	*os << "is mapped by the given callable to a value that ";
2250	} else {
2251	*os << "whose " << result_description_ << " ";
2252	}
2253	matcher_.DescribeTo(os);
2254	}
2255
2256	void DescribeNegationTo(::std::ostream* os) const override {
2257	if (result_description_.empty()) {
2258	*os << "is mapped by the given callable to a value that ";
2259	} else {
2260	*os << "whose " << result_description_ << " ";
2261	}
2262	matcher_.DescribeNegationTo(os);
2263	}
2264
2265	bool MatchAndExplain(T obj, MatchResultListener* listener) const override {
2266	if (result_description_.empty()) {
2267	*listener << "which is mapped by the given callable to ";
2268	} else {
2269	*listener << "whose " << result_description_ << " is ";
2270	}
2271	// Cannot pass the return value directly to MatchPrintAndExplain, which
2272	// takes a non-const reference as argument.
2273	// Also, specifying template argument explicitly is needed because T could
2274	// be a non-const reference (e.g. Matcher<Uncopyable&>).
2275	ResultType result =
2276	CallableTraits<Callable>::template Invoke<T>(callable_, obj);
2277	return MatchPrintAndExplain(result, matcher_, listener);
2278	}
2279
2280	private:
2281	const std::string result_description_;
2282	// Functors often define operator() as non-const method even though
2283	// they are actually stateless. But we need to use them even when
2284	// 'this' is a const pointer. It's the user's responsibility not to
2285	// use stateful callables with ResultOf(), which doesn't guarantee
2286	// how many times the callable will be invoked.
2287	mutable CallableStorageType callable_;
2288	const Matcher<ResultType> matcher_;
2289	}; // class Impl
2290
2291	const std::string result_description_;
2292	const CallableStorageType callable_;
2293	const InnerMatcher matcher_;
2294	};
2295
2296	// Implements a matcher that checks the size of an STL-style container.
2297	template <typename SizeMatcher>
2298	class SizeIsMatcher {
2299	public:
2300	explicit SizeIsMatcher(const SizeMatcher& size_matcher)
2301	: size_matcher_(size_matcher) {}
2302
2303	template <typename Container>
2304	operator Matcher<Container>() const {
2305	return Matcher<Container>(new Impl<const Container&>(size_matcher_));
2306	}
2307
2308	template <typename Container>
2309	class Impl : public MatcherInterface<Container> {
2310	public:
2311	using SizeType = decltype(std::declval<Container>().size());
2312	explicit Impl(const SizeMatcher& size_matcher)
2313	: size_matcher_(MatcherCast<SizeType>(size_matcher)) {}
2314
2315	void DescribeTo(::std::ostream* os) const override {
2316	*os << "has a size that ";
2317	size_matcher_.DescribeTo(os);
2318	}
2319	void DescribeNegationTo(::std::ostream* os) const override {
2320	*os << "has a size that ";
2321	size_matcher_.DescribeNegationTo(os);
2322	}
2323
2324	bool MatchAndExplain(Container container,
2325	MatchResultListener* listener) const override {
2326	SizeType size = container.size();
2327	StringMatchResultListener size_listener;
2328	const bool result = size_matcher_.MatchAndExplain(size, &size_listener);
2329	*listener << "whose size " << size
2330	<< (result ? " matches" : " doesn't match");
2331	PrintIfNotEmpty(explanation: size_listener.str(), os: listener->stream());
2332	return result;
2333	}
2334
2335	private:
2336	const Matcher<SizeType> size_matcher_;
2337	};
2338
2339	private:
2340	const SizeMatcher size_matcher_;
2341	};
2342
2343	// Implements a matcher that checks the begin()..end() distance of an STL-style
2344	// container.
2345	template <typename DistanceMatcher>
2346	class BeginEndDistanceIsMatcher {
2347	public:
2348	explicit BeginEndDistanceIsMatcher(const DistanceMatcher& distance_matcher)
2349	: distance_matcher_(distance_matcher) {}
2350
2351	template <typename Container>
2352	operator Matcher<Container>() const {
2353	return Matcher<Container>(new Impl<const Container&>(distance_matcher_));
2354	}
2355
2356	template <typename Container>
2357	class Impl : public MatcherInterface<Container> {
2358	public:
2359	// LLVM local change to support std::begin/std::end.
2360	//
2361	// typedef internal::StlContainerView<GTEST_REMOVE_REFERENCE_AND_CONST_(
2362	// Container)>
2363	// ContainerView;
2364	// typedef typename std::iterator_traits<
2365	// typename ContainerView::type::const_iterator>::difference_type
2366	// DistanceType;
2367	//
2368	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(Container) RawContainer;
2369	typedef internal::StlContainerView<RawContainer> View;
2370	typedef typename View::type StlContainer;
2371	typedef typename View::const_reference StlContainerReference;
2372	typedef decltype(std::begin(
2373	std::declval<StlContainerReference>())) StlContainerConstIterator;
2374	typedef typename std::iterator_traits<
2375	StlContainerConstIterator>::difference_type DistanceType;
2376	// LLVM local change end.
2377	explicit Impl(const DistanceMatcher& distance_matcher)
2378	: distance_matcher_(MatcherCast<DistanceType>(distance_matcher)) {}
2379
2380	void DescribeTo(::std::ostream* os) const override {
2381	*os << "distance between begin() and end() ";
2382	distance_matcher_.DescribeTo(os);
2383	}
2384	void DescribeNegationTo(::std::ostream* os) const override {
2385	*os << "distance between begin() and end() ";
2386	distance_matcher_.DescribeNegationTo(os);
2387	}
2388
2389	bool MatchAndExplain(Container container,
2390	MatchResultListener* listener) const override {
2391	using std::begin;
2392	using std::end;
2393	DistanceType distance = std::distance(begin(container), end(container));
2394	StringMatchResultListener distance_listener;
2395	const bool result =
2396	distance_matcher_.MatchAndExplain(distance, &distance_listener);
2397	*listener << "whose distance between begin() and end() " << distance
2398	<< (result ? " matches" : " doesn't match");
2399	PrintIfNotEmpty(explanation: distance_listener.str(), os: listener->stream());
2400	return result;
2401	}
2402
2403	private:
2404	const Matcher<DistanceType> distance_matcher_;
2405	};
2406
2407	private:
2408	const DistanceMatcher distance_matcher_;
2409	};
2410
2411	// Implements an equality matcher for any STL-style container whose elements
2412	// support ==. This matcher is like Eq(), but its failure explanations provide
2413	// more detailed information that is useful when the container is used as a set.
2414	// The failure message reports elements that are in one of the operands but not
2415	// the other. The failure messages do not report duplicate or out-of-order
2416	// elements in the containers (which don't properly matter to sets, but can
2417	// occur if the containers are vectors or lists, for example).
2418	//
2419	// Uses the container's const_iterator, value_type, operator ==,
2420	// begin(), and end().
2421	template <typename Container>
2422	class ContainerEqMatcher {
2423	public:
2424	typedef internal::StlContainerView<Container> View;
2425	typedef typename View::type StlContainer;
2426	typedef typename View::const_reference StlContainerReference;
2427
2428	static_assert(!std::is_const<Container>::value,
2429	"Container type must not be const");
2430	static_assert(!std::is_reference<Container>::value,
2431	"Container type must not be a reference");
2432
2433	// We make a copy of expected in case the elements in it are modified
2434	// after this matcher is created.
2435	explicit ContainerEqMatcher(const Container& expected)
2436	: expected_(View::Copy(expected)) {}
2437
2438	void DescribeTo(::std::ostream* os) const {
2439	*os << "equals ";
2440	UniversalPrint(expected_, os);
2441	}
2442	void DescribeNegationTo(::std::ostream* os) const {
2443	*os << "does not equal ";
2444	UniversalPrint(expected_, os);
2445	}
2446
2447	template <typename LhsContainer>
2448	bool MatchAndExplain(const LhsContainer& lhs,
2449	MatchResultListener* listener) const {
2450	typedef internal::StlContainerView<
2451	typename std::remove_const<LhsContainer>::type>
2452	LhsView;
2453	StlContainerReference lhs_stl_container = LhsView::ConstReference(lhs);
2454	if (lhs_stl_container == expected_) return true;
2455
2456	::std::ostream* const os = listener->stream();
2457	if (os != nullptr) {
2458	// Something is different. Check for extra values first.
2459	bool printed_header = false;
2460	for (auto it = lhs_stl_container.begin(); it != lhs_stl_container.end();
2461	++it) {
2462	if (internal::ArrayAwareFind(expected_.begin(), expected_.end(), *it) ==
2463	expected_.end()) {
2464	if (printed_header) {
2465	*os << ", ";
2466	} else {
2467	*os << "which has these unexpected elements: ";
2468	printed_header = true;
2469	}
2470	UniversalPrint(*it, os);
2471	}
2472	}
2473
2474	// Now check for missing values.
2475	bool printed_header2 = false;
2476	for (auto it = expected_.begin(); it != expected_.end(); ++it) {
2477	if (internal::ArrayAwareFind(lhs_stl_container.begin(),
2478	lhs_stl_container.end(),
2479	*it) == lhs_stl_container.end()) {
2480	if (printed_header2) {
2481	*os << ", ";
2482	} else {
2483	*os << (printed_header ? ",\nand" : "which")
2484	<< " doesn't have these expected elements: ";
2485	printed_header2 = true;
2486	}
2487	UniversalPrint(*it, os);
2488	}
2489	}
2490	}
2491
2492	return false;
2493	}
2494
2495	private:
2496	const StlContainer expected_;
2497	};
2498
2499	// A comparator functor that uses the < operator to compare two values.
2500	struct LessComparator {
2501	template <typename T, typename U>
2502	bool operator()(const T& lhs, const U& rhs) const {
2503	return lhs < rhs;
2504	}
2505	};
2506
2507	// Implements WhenSortedBy(comparator, container_matcher).
2508	template <typename Comparator, typename ContainerMatcher>
2509	class WhenSortedByMatcher {
2510	public:
2511	WhenSortedByMatcher(const Comparator& comparator,
2512	const ContainerMatcher& matcher)
2513	: comparator_(comparator), matcher_(matcher) {}
2514
2515	template <typename LhsContainer>
2516	operator Matcher<LhsContainer>() const {
2517	return MakeMatcher(new Impl<LhsContainer>(comparator_, matcher_));
2518	}
2519
2520	template <typename LhsContainer>
2521	class Impl : public MatcherInterface<LhsContainer> {
2522	public:
2523	typedef internal::StlContainerView<GTEST_REMOVE_REFERENCE_AND_CONST_(
2524	LhsContainer)>
2525	LhsView;
2526	typedef typename LhsView::type LhsStlContainer;
2527	typedef typename LhsView::const_reference LhsStlContainerReference;
2528	// Transforms std::pair<const Key, Value> into std::pair<Key, Value>
2529	// so that we can match associative containers.
2530	typedef
2531	typename RemoveConstFromKey<typename LhsStlContainer::value_type>::type
2532	LhsValue;
2533
2534	Impl(const Comparator& comparator, const ContainerMatcher& matcher)
2535	: comparator_(comparator), matcher_(matcher) {}
2536
2537	void DescribeTo(::std::ostream* os) const override {
2538	*os << "(when sorted) ";
2539	matcher_.DescribeTo(os);
2540	}
2541
2542	void DescribeNegationTo(::std::ostream* os) const override {
2543	*os << "(when sorted) ";
2544	matcher_.DescribeNegationTo(os);
2545	}
2546
2547	bool MatchAndExplain(LhsContainer lhs,
2548	MatchResultListener* listener) const override {
2549	LhsStlContainerReference lhs_stl_container = LhsView::ConstReference(lhs);
2550	::std::vector<LhsValue> sorted_container(lhs_stl_container.begin(),
2551	lhs_stl_container.end());
2552	::std::sort(sorted_container.begin(), sorted_container.end(),
2553	comparator_);
2554
2555	if (!listener->IsInterested()) {
2556	// If the listener is not interested, we do not need to
2557	// construct the inner explanation.
2558	return matcher_.Matches(sorted_container);
2559	}
2560
2561	*listener << "which is ";
2562	UniversalPrint(sorted_container, listener->stream());
2563	*listener << " when sorted";
2564
2565	StringMatchResultListener inner_listener;
2566	const bool match =
2567	matcher_.MatchAndExplain(sorted_container, &inner_listener);
2568	PrintIfNotEmpty(explanation: inner_listener.str(), os: listener->stream());
2569	return match;
2570	}
2571
2572	private:
2573	const Comparator comparator_;
2574	const Matcher<const ::std::vector<LhsValue>&> matcher_;
2575
2576	Impl(const Impl&) = delete;
2577	Impl& operator=(const Impl&) = delete;
2578	};
2579
2580	private:
2581	const Comparator comparator_;
2582	const ContainerMatcher matcher_;
2583	};
2584
2585	// Implements Pointwise(tuple_matcher, rhs_container). tuple_matcher
2586	// must be able to be safely cast to Matcher<std::tuple<const T1&, const
2587	// T2&> >, where T1 and T2 are the types of elements in the LHS
2588	// container and the RHS container respectively.
2589	template <typename TupleMatcher, typename RhsContainer>
2590	class PointwiseMatcher {
2591	static_assert(
2592	!IsHashTable<GTEST_REMOVE_REFERENCE_AND_CONST_(RhsContainer)>::value,
2593	"use UnorderedPointwise with hash tables");
2594
2595	public:
2596	typedef internal::StlContainerView<RhsContainer> RhsView;
2597	typedef typename RhsView::type RhsStlContainer;
2598	typedef typename RhsStlContainer::value_type RhsValue;
2599
2600	static_assert(!std::is_const<RhsContainer>::value,
2601	"RhsContainer type must not be const");
2602	static_assert(!std::is_reference<RhsContainer>::value,
2603	"RhsContainer type must not be a reference");
2604
2605	// Like ContainerEq, we make a copy of rhs in case the elements in
2606	// it are modified after this matcher is created.
2607	PointwiseMatcher(const TupleMatcher& tuple_matcher, const RhsContainer& rhs)
2608	: tuple_matcher_(tuple_matcher), rhs_(RhsView::Copy(rhs)) {}
2609
2610	template <typename LhsContainer>
2611	operator Matcher<LhsContainer>() const {
2612	static_assert(
2613	!IsHashTable<GTEST_REMOVE_REFERENCE_AND_CONST_(LhsContainer)>::value,
2614	"use UnorderedPointwise with hash tables");
2615
2616	return Matcher<LhsContainer>(
2617	new Impl<const LhsContainer&>(tuple_matcher_, rhs_));
2618	}
2619
2620	template <typename LhsContainer>
2621	class Impl : public MatcherInterface<LhsContainer> {
2622	public:
2623	typedef internal::StlContainerView<GTEST_REMOVE_REFERENCE_AND_CONST_(
2624	LhsContainer)>
2625	LhsView;
2626	typedef typename LhsView::type LhsStlContainer;
2627	typedef typename LhsView::const_reference LhsStlContainerReference;
2628	typedef typename LhsStlContainer::value_type LhsValue;
2629	// We pass the LHS value and the RHS value to the inner matcher by
2630	// reference, as they may be expensive to copy. We must use tuple
2631	// instead of pair here, as a pair cannot hold references (C++ 98,
2632	// 20.2.2 [lib.pairs]).
2633	typedef ::std::tuple<const LhsValue&, const RhsValue&> InnerMatcherArg;
2634
2635	Impl(const TupleMatcher& tuple_matcher, const RhsStlContainer& rhs)
2636	// mono_tuple_matcher_ holds a monomorphic version of the tuple matcher.
2637	: mono_tuple_matcher_(SafeMatcherCast<InnerMatcherArg>(tuple_matcher)),
2638	rhs_(rhs) {}
2639
2640	void DescribeTo(::std::ostream* os) const override {
2641	*os << "contains " << rhs_.size()
2642	<< " values, where each value and its corresponding value in ";
2643	UniversalPrinter<RhsStlContainer>::Print(rhs_, os);
2644	*os << " ";
2645	mono_tuple_matcher_.DescribeTo(os);
2646	}
2647	void DescribeNegationTo(::std::ostream* os) const override {
2648	*os << "doesn't contain exactly " << rhs_.size()
2649	<< " values, or contains a value x at some index i"
2650	<< " where x and the i-th value of ";
2651	UniversalPrint(rhs_, os);
2652	*os << " ";
2653	mono_tuple_matcher_.DescribeNegationTo(os);
2654	}
2655
2656	bool MatchAndExplain(LhsContainer lhs,
2657	MatchResultListener* listener) const override {
2658	LhsStlContainerReference lhs_stl_container = LhsView::ConstReference(lhs);
2659	const size_t actual_size = lhs_stl_container.size();
2660	if (actual_size != rhs_.size()) {
2661	*listener << "which contains " << actual_size << " values";
2662	return false;
2663	}
2664
2665	auto left = lhs_stl_container.begin();
2666	auto right = rhs_.begin();
2667	for (size_t i = 0; i != actual_size; ++i, ++left, ++right) {
2668	if (listener->IsInterested()) {
2669	StringMatchResultListener inner_listener;
2670	// Create InnerMatcherArg as a temporarily object to avoid it outlives
2671	// *left and *right. Dereference or the conversion to `const T&` may
2672	// return temp objects, e.g. for vector<bool>.
2673	if (!mono_tuple_matcher_.MatchAndExplain(
2674	InnerMatcherArg(ImplicitCast_<const LhsValue&>(*left),
2675	ImplicitCast_<const RhsValue&>(*right)),
2676	&inner_listener)) {
2677	*listener << "where the value pair (";
2678	UniversalPrint(*left, listener->stream());
2679	*listener << ", ";
2680	UniversalPrint(*right, listener->stream());
2681	*listener << ") at index #" << i << " don't match";
2682	PrintIfNotEmpty(explanation: inner_listener.str(), os: listener->stream());
2683	return false;
2684	}
2685	} else {
2686	if (!mono_tuple_matcher_.Matches(
2687	InnerMatcherArg(ImplicitCast_<const LhsValue&>(*left),
2688	ImplicitCast_<const RhsValue&>(*right))))
2689	return false;
2690	}
2691	}
2692
2693	return true;
2694	}
2695
2696	private:
2697	const Matcher<InnerMatcherArg> mono_tuple_matcher_;
2698	const RhsStlContainer rhs_;
2699	};
2700
2701	private:
2702	const TupleMatcher tuple_matcher_;
2703	const RhsStlContainer rhs_;
2704	};
2705
2706	// Holds the logic common to ContainsMatcherImpl and EachMatcherImpl.
2707	template <typename Container>
2708	class QuantifierMatcherImpl : public MatcherInterface<Container> {
2709	public:
2710	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(Container) RawContainer;
2711	typedef StlContainerView<RawContainer> View;
2712	typedef typename View::type StlContainer;
2713	typedef typename View::const_reference StlContainerReference;
2714	typedef typename StlContainer::value_type Element;
2715
2716	template <typename InnerMatcher>
2717	explicit QuantifierMatcherImpl(InnerMatcher inner_matcher)
2718	: inner_matcher_(
2719	testing::SafeMatcherCast<const Element&>(inner_matcher)) {}
2720
2721	// Checks whether:
2722	// * All elements in the container match, if all_elements_should_match.
2723	// * Any element in the container matches, if !all_elements_should_match.
2724	bool MatchAndExplainImpl(bool all_elements_should_match, Container container,
2725	MatchResultListener* listener) const {
2726	StlContainerReference stl_container = View::ConstReference(container);
2727	size_t i = 0;
2728	for (auto it = stl_container.begin(); it != stl_container.end();
2729	++it, ++i) {
2730	StringMatchResultListener inner_listener;
2731	const bool matches = inner_matcher_.MatchAndExplain(*it, &inner_listener);
2732
2733	if (matches != all_elements_should_match) {
2734	*listener << "whose element #" << i
2735	<< (matches ? " matches" : " doesn't match");
2736	PrintIfNotEmpty(explanation: inner_listener.str(), os: listener->stream());
2737	return !all_elements_should_match;
2738	}
2739	}
2740	return all_elements_should_match;
2741	}
2742
2743	bool MatchAndExplainImpl(const Matcher<size_t>& count_matcher,
2744	Container container,
2745	MatchResultListener* listener) const {
2746	StlContainerReference stl_container = View::ConstReference(container);
2747	size_t i = 0;
2748	std::vector<size_t> match_elements;
2749	for (auto it = stl_container.begin(); it != stl_container.end();
2750	++it, ++i) {
2751	StringMatchResultListener inner_listener;
2752	const bool matches = inner_matcher_.MatchAndExplain(*it, &inner_listener);
2753	if (matches) {
2754	match_elements.push_back(x: i);
2755	}
2756	}
2757	if (listener->IsInterested()) {
2758	if (match_elements.empty()) {
2759	*listener << "has no element that matches";
2760	} else if (match_elements.size() == 1) {
2761	*listener << "whose element #" << match_elements[0] << " matches";
2762	} else {
2763	*listener << "whose elements (";
2764	std::string sep = "";
2765	for (size_t e : match_elements) {
2766	*listener << sep << e;
2767	sep = ", ";
2768	}
2769	*listener << ") match";
2770	}
2771	}
2772	StringMatchResultListener count_listener;
2773	if (count_matcher.MatchAndExplain(x: match_elements.size(), listener: &count_listener)) {
2774	*listener << " and whose match quantity of " << match_elements.size()
2775	<< " matches";
2776	PrintIfNotEmpty(explanation: count_listener.str(), os: listener->stream());
2777	return true;
2778	} else {
2779	if (match_elements.empty()) {
2780	*listener << " and";
2781	} else {
2782	*listener << " but";
2783	}
2784	*listener << " whose match quantity of " << match_elements.size()
2785	<< " does not match";
2786	PrintIfNotEmpty(explanation: count_listener.str(), os: listener->stream());
2787	return false;
2788	}
2789	}
2790
2791	protected:
2792	const Matcher<const Element&> inner_matcher_;
2793	};
2794
2795	// Implements Contains(element_matcher) for the given argument type Container.
2796	// Symmetric to EachMatcherImpl.
2797	template <typename Container>
2798	class ContainsMatcherImpl : public QuantifierMatcherImpl<Container> {
2799	public:
2800	template <typename InnerMatcher>
2801	explicit ContainsMatcherImpl(InnerMatcher inner_matcher)
2802	: QuantifierMatcherImpl<Container>(inner_matcher) {}
2803
2804	// Describes what this matcher does.
2805	void DescribeTo(::std::ostream* os) const override {
2806	*os << "contains at least one element that ";
2807	this->inner_matcher_.DescribeTo(os);
2808	}
2809
2810	void DescribeNegationTo(::std::ostream* os) const override {
2811	*os << "doesn't contain any element that ";
2812	this->inner_matcher_.DescribeTo(os);
2813	}
2814
2815	bool MatchAndExplain(Container container,
2816	MatchResultListener* listener) const override {
2817	return this->MatchAndExplainImpl(false, container, listener);
2818	}
2819	};
2820
2821	// Implements Each(element_matcher) for the given argument type Container.
2822	// Symmetric to ContainsMatcherImpl.
2823	template <typename Container>
2824	class EachMatcherImpl : public QuantifierMatcherImpl<Container> {
2825	public:
2826	template <typename InnerMatcher>
2827	explicit EachMatcherImpl(InnerMatcher inner_matcher)
2828	: QuantifierMatcherImpl<Container>(inner_matcher) {}
2829
2830	// Describes what this matcher does.
2831	void DescribeTo(::std::ostream* os) const override {
2832	*os << "only contains elements that ";
2833	this->inner_matcher_.DescribeTo(os);
2834	}
2835
2836	void DescribeNegationTo(::std::ostream* os) const override {
2837	*os << "contains some element that ";
2838	this->inner_matcher_.DescribeNegationTo(os);
2839	}
2840
2841	bool MatchAndExplain(Container container,
2842	MatchResultListener* listener) const override {
2843	return this->MatchAndExplainImpl(true, container, listener);
2844	}
2845	};
2846
2847	// Implements Contains(element_matcher).Times(n) for the given argument type
2848	// Container.
2849	template <typename Container>
2850	class ContainsTimesMatcherImpl : public QuantifierMatcherImpl<Container> {
2851	public:
2852	template <typename InnerMatcher>
2853	explicit ContainsTimesMatcherImpl(InnerMatcher inner_matcher,
2854	Matcher<size_t> count_matcher)
2855	: QuantifierMatcherImpl<Container>(inner_matcher),
2856	count_matcher_(std::move(count_matcher)) {}
2857
2858	void DescribeTo(::std::ostream* os) const override {
2859	*os << "quantity of elements that match ";
2860	this->inner_matcher_.DescribeTo(os);
2861	*os << " ";
2862	count_matcher_.DescribeTo(os);
2863	}
2864
2865	void DescribeNegationTo(::std::ostream* os) const override {
2866	*os << "quantity of elements that match ";
2867	this->inner_matcher_.DescribeTo(os);
2868	*os << " ";
2869	count_matcher_.DescribeNegationTo(os);
2870	}
2871
2872	bool MatchAndExplain(Container container,
2873	MatchResultListener* listener) const override {
2874	return this->MatchAndExplainImpl(count_matcher_, container, listener);
2875	}
2876
2877	private:
2878	const Matcher<size_t> count_matcher_;
2879	};
2880
2881	// Implements polymorphic Contains(element_matcher).Times(n).
2882	template <typename M>
2883	class ContainsTimesMatcher {
2884	public:
2885	explicit ContainsTimesMatcher(M m, Matcher<size_t> count_matcher)
2886	: inner_matcher_(m), count_matcher_(std::move(count_matcher)) {}
2887
2888	template <typename Container>
2889	operator Matcher<Container>() const { // NOLINT
2890	return Matcher<Container>(new ContainsTimesMatcherImpl<const Container&>(
2891	inner_matcher_, count_matcher_));
2892	}
2893
2894	private:
2895	const M inner_matcher_;
2896	const Matcher<size_t> count_matcher_;
2897	};
2898
2899	// Implements polymorphic Contains(element_matcher).
2900	template <typename M>
2901	class ContainsMatcher {
2902	public:
2903	explicit ContainsMatcher(M m) : inner_matcher_(m) {}
2904
2905	template <typename Container>
2906	operator Matcher<Container>() const { // NOLINT
2907	return Matcher<Container>(
2908	new ContainsMatcherImpl<const Container&>(inner_matcher_));
2909	}
2910
2911	ContainsTimesMatcher<M> Times(Matcher<size_t> count_matcher) const {
2912	return ContainsTimesMatcher<M>(inner_matcher_, std::move(count_matcher));
2913	}
2914
2915	private:
2916	const M inner_matcher_;
2917	};
2918
2919	// Implements polymorphic Each(element_matcher).
2920	template <typename M>
2921	class EachMatcher {
2922	public:
2923	explicit EachMatcher(M m) : inner_matcher_(m) {}
2924
2925	template <typename Container>
2926	operator Matcher<Container>() const { // NOLINT
2927	return Matcher<Container>(
2928	new EachMatcherImpl<const Container&>(inner_matcher_));
2929	}
2930
2931	private:
2932	const M inner_matcher_;
2933	};
2934
2935	struct Rank1 {};
2936	struct Rank0 : Rank1 {};
2937
2938	namespace pair_getters {
2939	using std::get;
2940	template <typename T>
2941	auto First(T& x, Rank1) -> decltype(get<0>(x)) { // NOLINT
2942	return get<0>(x);
2943	}
2944	template <typename T>
2945	auto First(T& x, Rank0) -> decltype((x.first)) { // NOLINT
2946	return x.first;
2947	}
2948
2949	template <typename T>
2950	auto Second(T& x, Rank1) -> decltype(get<1>(x)) { // NOLINT
2951	return get<1>(x);
2952	}
2953	template <typename T>
2954	auto Second(T& x, Rank0) -> decltype((x.second)) { // NOLINT
2955	return x.second;
2956	}
2957	} // namespace pair_getters
2958
2959	// Implements Key(inner_matcher) for the given argument pair type.
2960	// Key(inner_matcher) matches an std::pair whose 'first' field matches
2961	// inner_matcher. For example, Contains(Key(Ge(5))) can be used to match an
2962	// std::map that contains at least one element whose key is >= 5.
2963	template <typename PairType>
2964	class KeyMatcherImpl : public MatcherInterface<PairType> {
2965	public:
2966	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(PairType) RawPairType;
2967	typedef typename RawPairType::first_type KeyType;
2968
2969	template <typename InnerMatcher>
2970	explicit KeyMatcherImpl(InnerMatcher inner_matcher)
2971	: inner_matcher_(
2972	testing::SafeMatcherCast<const KeyType&>(inner_matcher)) {}
2973
2974	// Returns true if and only if 'key_value.first' (the key) matches the inner
2975	// matcher.
2976	bool MatchAndExplain(PairType key_value,
2977	MatchResultListener* listener) const override {
2978	StringMatchResultListener inner_listener;
2979	const bool match = inner_matcher_.MatchAndExplain(
2980	pair_getters::First(key_value, Rank0()), &inner_listener);
2981	const std::string explanation = inner_listener.str();
2982	if (!explanation.empty()) {
2983	*listener << "whose first field is a value " << explanation;
2984	}
2985	return match;
2986	}
2987
2988	// Describes what this matcher does.
2989	void DescribeTo(::std::ostream* os) const override {
2990	*os << "has a key that ";
2991	inner_matcher_.DescribeTo(os);
2992	}
2993
2994	// Describes what the negation of this matcher does.
2995	void DescribeNegationTo(::std::ostream* os) const override {
2996	*os << "doesn't have a key that ";
2997	inner_matcher_.DescribeTo(os);
2998	}
2999
3000	private:
3001	const Matcher<const KeyType&> inner_matcher_;
3002	};
3003
3004	// Implements polymorphic Key(matcher_for_key).
3005	template <typename M>
3006	class KeyMatcher {
3007	public:
3008	explicit KeyMatcher(M m) : matcher_for_key_(m) {}
3009
3010	template <typename PairType>
3011	operator Matcher<PairType>() const {
3012	return Matcher<PairType>(
3013	new KeyMatcherImpl<const PairType&>(matcher_for_key_));
3014	}
3015
3016	private:
3017	const M matcher_for_key_;
3018	};
3019
3020	// Implements polymorphic Address(matcher_for_address).
3021	template <typename InnerMatcher>
3022	class AddressMatcher {
3023	public:
3024	explicit AddressMatcher(InnerMatcher m) : matcher_(m) {}
3025
3026	template <typename Type>
3027	operator Matcher<Type>() const { // NOLINT
3028	return Matcher<Type>(new Impl<const Type&>(matcher_));
3029	}
3030
3031	private:
3032	// The monomorphic implementation that works for a particular object type.
3033	template <typename Type>
3034	class Impl : public MatcherInterface<Type> {
3035	public:
3036	using Address = const GTEST_REMOVE_REFERENCE_AND_CONST_(Type) *;
3037	explicit Impl(const InnerMatcher& matcher)
3038	: matcher_(MatcherCast<Address>(matcher)) {}
3039
3040	void DescribeTo(::std::ostream* os) const override {
3041	*os << "has address that ";
3042	matcher_.DescribeTo(os);
3043	}
3044
3045	void DescribeNegationTo(::std::ostream* os) const override {
3046	*os << "does not have address that ";
3047	matcher_.DescribeTo(os);
3048	}
3049
3050	bool MatchAndExplain(Type object,
3051	MatchResultListener* listener) const override {
3052	*listener << "which has address ";
3053	Address address = std::addressof(object);
3054	return MatchPrintAndExplain(address, matcher_, listener);
3055	}
3056
3057	private:
3058	const Matcher<Address> matcher_;
3059	};
3060	const InnerMatcher matcher_;
3061	};
3062
3063	// Implements Pair(first_matcher, second_matcher) for the given argument pair
3064	// type with its two matchers. See Pair() function below.
3065	template <typename PairType>
3066	class PairMatcherImpl : public MatcherInterface<PairType> {
3067	public:
3068	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(PairType) RawPairType;
3069	typedef typename RawPairType::first_type FirstType;
3070	typedef typename RawPairType::second_type SecondType;
3071
3072	template <typename FirstMatcher, typename SecondMatcher>
3073	PairMatcherImpl(FirstMatcher first_matcher, SecondMatcher second_matcher)
3074	: first_matcher_(
3075	testing::SafeMatcherCast<const FirstType&>(first_matcher)),
3076	second_matcher_(
3077	testing::SafeMatcherCast<const SecondType&>(second_matcher)) {}
3078
3079	// Describes what this matcher does.
3080	void DescribeTo(::std::ostream* os) const override {
3081	*os << "has a first field that ";
3082	first_matcher_.DescribeTo(os);
3083	*os << ", and has a second field that ";
3084	second_matcher_.DescribeTo(os);
3085	}
3086
3087	// Describes what the negation of this matcher does.
3088	void DescribeNegationTo(::std::ostream* os) const override {
3089	*os << "has a first field that ";
3090	first_matcher_.DescribeNegationTo(os);
3091	*os << ", or has a second field that ";
3092	second_matcher_.DescribeNegationTo(os);
3093	}
3094
3095	// Returns true if and only if 'a_pair.first' matches first_matcher and
3096	// 'a_pair.second' matches second_matcher.
3097	bool MatchAndExplain(PairType a_pair,
3098	MatchResultListener* listener) const override {
3099	if (!listener->IsInterested()) {
3100	// If the listener is not interested, we don't need to construct the
3101	// explanation.
3102	return first_matcher_.Matches(pair_getters::First(a_pair, Rank0())) &&
3103	second_matcher_.Matches(pair_getters::Second(a_pair, Rank0()));
3104	}
3105	StringMatchResultListener first_inner_listener;
3106	if (!first_matcher_.MatchAndExplain(pair_getters::First(a_pair, Rank0()),
3107	&first_inner_listener)) {
3108	*listener << "whose first field does not match";
3109	PrintIfNotEmpty(explanation: first_inner_listener.str(), os: listener->stream());
3110	return false;
3111	}
3112	StringMatchResultListener second_inner_listener;
3113	if (!second_matcher_.MatchAndExplain(pair_getters::Second(a_pair, Rank0()),
3114	&second_inner_listener)) {
3115	*listener << "whose second field does not match";
3116	PrintIfNotEmpty(explanation: second_inner_listener.str(), os: listener->stream());
3117	return false;
3118	}
3119	ExplainSuccess(first_explanation: first_inner_listener.str(), second_explanation: second_inner_listener.str(),
3120	listener);
3121	return true;
3122	}
3123
3124	private:
3125	void ExplainSuccess(const std::string& first_explanation,
3126	const std::string& second_explanation,
3127	MatchResultListener* listener) const {
3128	*listener << "whose both fields match";
3129	if (!first_explanation.empty()) {
3130	*listener << ", where the first field is a value " << first_explanation;
3131	}
3132	if (!second_explanation.empty()) {
3133	*listener << ", ";
3134	if (!first_explanation.empty()) {
3135	*listener << "and ";
3136	} else {
3137	*listener << "where ";
3138	}
3139	*listener << "the second field is a value " << second_explanation;
3140	}
3141	}
3142
3143	const Matcher<const FirstType&> first_matcher_;
3144	const Matcher<const SecondType&> second_matcher_;
3145	};
3146
3147	// Implements polymorphic Pair(first_matcher, second_matcher).
3148	template <typename FirstMatcher, typename SecondMatcher>
3149	class PairMatcher {
3150	public:
3151	PairMatcher(FirstMatcher first_matcher, SecondMatcher second_matcher)
3152	: first_matcher_(first_matcher), second_matcher_(second_matcher) {}
3153
3154	template <typename PairType>
3155	operator Matcher<PairType>() const {
3156	return Matcher<PairType>(
3157	new PairMatcherImpl<const PairType&>(first_matcher_, second_matcher_));
3158	}
3159
3160	private:
3161	const FirstMatcher first_matcher_;
3162	const SecondMatcher second_matcher_;
3163	};
3164
3165	template <typename T, size_t... I>
3166	auto UnpackStructImpl(const T& t, IndexSequence<I...>, int)
3167	-> decltype(std::tie(get<I>(t)...)) {
3168	static_assert(std::tuple_size<T>::value == sizeof...(I),
3169	"Number of arguments doesn't match the number of fields.");
3170	return std::tie(get<I>(t)...);
3171	}
3172
3173	#if defined(__cpp_structured_bindings) && __cpp_structured_bindings >= 201606
3174	template <typename T>
3175	auto UnpackStructImpl(const T& t, MakeIndexSequence<1>, char) {
3176	const auto& [a] = t;
3177	return std::tie(a);
3178	}
3179	template <typename T>
3180	auto UnpackStructImpl(const T& t, MakeIndexSequence<2>, char) {
3181	const auto& [a, b] = t;
3182	return std::tie(a, b);
3183	}
3184	template <typename T>
3185	auto UnpackStructImpl(const T& t, MakeIndexSequence<3>, char) {
3186	const auto& [a, b, c] = t;
3187	return std::tie(a, b, c);
3188	}
3189	template <typename T>
3190	auto UnpackStructImpl(const T& t, MakeIndexSequence<4>, char) {
3191	const auto& [a, b, c, d] = t;
3192	return std::tie(a, b, c, d);
3193	}
3194	template <typename T>
3195	auto UnpackStructImpl(const T& t, MakeIndexSequence<5>, char) {
3196	const auto& [a, b, c, d, e] = t;
3197	return std::tie(a, b, c, d, e);
3198	}
3199	template <typename T>
3200	auto UnpackStructImpl(const T& t, MakeIndexSequence<6>, char) {
3201	const auto& [a, b, c, d, e, f] = t;
3202	return std::tie(a, b, c, d, e, f);
3203	}
3204	template <typename T>
3205	auto UnpackStructImpl(const T& t, MakeIndexSequence<7>, char) {
3206	const auto& [a, b, c, d, e, f, g] = t;
3207	return std::tie(a, b, c, d, e, f, g);
3208	}
3209	template <typename T>
3210	auto UnpackStructImpl(const T& t, MakeIndexSequence<8>, char) {
3211	const auto& [a, b, c, d, e, f, g, h] = t;
3212	return std::tie(a, b, c, d, e, f, g, h);
3213	}
3214	template <typename T>
3215	auto UnpackStructImpl(const T& t, MakeIndexSequence<9>, char) {
3216	const auto& [a, b, c, d, e, f, g, h, i] = t;
3217	return std::tie(a, b, c, d, e, f, g, h, i);
3218	}
3219	template <typename T>
3220	auto UnpackStructImpl(const T& t, MakeIndexSequence<10>, char) {
3221	const auto& [a, b, c, d, e, f, g, h, i, j] = t;
3222	return std::tie(a, b, c, d, e, f, g, h, i, j);
3223	}
3224	template <typename T>
3225	auto UnpackStructImpl(const T& t, MakeIndexSequence<11>, char) {
3226	const auto& [a, b, c, d, e, f, g, h, i, j, k] = t;
3227	return std::tie(a, b, c, d, e, f, g, h, i, j, k);
3228	}
3229	template <typename T>
3230	auto UnpackStructImpl(const T& t, MakeIndexSequence<12>, char) {
3231	const auto& [a, b, c, d, e, f, g, h, i, j, k, l] = t;
3232	return std::tie(a, b, c, d, e, f, g, h, i, j, k, l);
3233	}
3234	template <typename T>
3235	auto UnpackStructImpl(const T& t, MakeIndexSequence<13>, char) {
3236	const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m] = t;
3237	return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m);
3238	}
3239	template <typename T>
3240	auto UnpackStructImpl(const T& t, MakeIndexSequence<14>, char) {
3241	const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n] = t;
3242	return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n);
3243	}
3244	template <typename T>
3245	auto UnpackStructImpl(const T& t, MakeIndexSequence<15>, char) {
3246	const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o] = t;
3247	return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o);
3248	}
3249	template <typename T>
3250	auto UnpackStructImpl(const T& t, MakeIndexSequence<16>, char) {
3251	const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p] = t;
3252	return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p);
3253	}
3254	template <typename T>
3255	auto UnpackStructImpl(const T& t, MakeIndexSequence<17>, char) {
3256	const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q] = t;
3257	return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q);
3258	}
3259	template <typename T>
3260	auto UnpackStructImpl(const T& t, MakeIndexSequence<18>, char) {
3261	const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r] = t;
3262	return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r);
3263	}
3264	template <typename T>
3265	auto UnpackStructImpl(const T& t, MakeIndexSequence<19>, char) {
3266	const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s] = t;
3267	return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s);
3268	}
3269	#endif // defined(__cpp_structured_bindings)
3270
3271	template <size_t I, typename T>
3272	auto UnpackStruct(const T& t)
3273	-> decltype((UnpackStructImpl)(t, MakeIndexSequence<I>{}, 0)) {
3274	return (UnpackStructImpl)(t, MakeIndexSequence<I>{}, 0);
3275	}
3276
3277	// Helper function to do comma folding in C++11.
3278	// The array ensures left-to-right order of evaluation.
3279	// Usage: VariadicExpand({expr...});
3280	template <typename T, size_t N>
3281	void VariadicExpand(const T (&)[N]) {}
3282
3283	template <typename Struct, typename StructSize>
3284	class FieldsAreMatcherImpl;
3285
3286	template <typename Struct, size_t... I>
3287	class FieldsAreMatcherImpl<Struct, IndexSequence<I...>>
3288	: public MatcherInterface<Struct> {
3289	using UnpackedType =
3290	decltype(UnpackStruct<sizeof...(I)>(std::declval<const Struct&>()));
3291	using MatchersType = std::tuple<
3292	Matcher<const typename std::tuple_element<I, UnpackedType>::type&>...>;
3293
3294	public:
3295	template <typename Inner>
3296	explicit FieldsAreMatcherImpl(const Inner& matchers)
3297	: matchers_(testing::SafeMatcherCast<
3298	const typename std::tuple_element<I, UnpackedType>::type&>(
3299	std::get<I>(matchers))...) {}
3300
3301	void DescribeTo(::std::ostream* os) const override {
3302	const char* separator = "";
3303	VariadicExpand(
3304	{(*os << separator << "has field #" << I << " that ",
3305	std::get<I>(matchers_).DescribeTo(os), separator = ", and ")...});
3306	}
3307
3308	void DescribeNegationTo(::std::ostream* os) const override {
3309	const char* separator = "";
3310	VariadicExpand({(*os << separator << "has field #" << I << " that ",
3311	std::get<I>(matchers_).DescribeNegationTo(os),
3312	separator = ", or ")...});
3313	}
3314
3315	bool MatchAndExplain(Struct t, MatchResultListener* listener) const override {
3316	return MatchInternal(tuple: (UnpackStruct<sizeof...(I)>)(t), listener);
3317	}
3318
3319	private:
3320	bool MatchInternal(UnpackedType tuple, MatchResultListener* listener) const {
3321	if (!listener->IsInterested()) {
3322	// If the listener is not interested, we don't need to construct the
3323	// explanation.
3324	bool good = true;
3325	VariadicExpand({good = good && std::get<I>(matchers_).Matches(
3326	std::get<I>(tuple))...});
3327	return good;
3328	}
3329
3330	size_t failed_pos = ~size_t{};
3331
3332	std::vector<StringMatchResultListener> inner_listener(sizeof...(I));
3333
3334	VariadicExpand(
3335	{failed_pos == ~size_t{} && !std::get<I>(matchers_).MatchAndExplain(
3336	std::get<I>(tuple), &inner_listener[I])
3337	? failed_pos = I
3338	: 0 ...});
3339	if (failed_pos != ~size_t{}) {
3340	*listener << "whose field #" << failed_pos << " does not match";
3341	PrintIfNotEmpty(explanation: inner_listener[failed_pos].str(), os: listener->stream());
3342	return false;
3343	}
3344
3345	*listener << "whose all elements match";
3346	const char* separator = ", where";
3347	for (size_t index = 0; index < sizeof...(I); ++index) {
3348	const std::string str = inner_listener[index].str();
3349	if (!str.empty()) {
3350	*listener << separator << " field #" << index << " is a value " << str;
3351	separator = ", and";
3352	}
3353	}
3354
3355	return true;
3356	}
3357
3358	MatchersType matchers_;
3359	};
3360
3361	template <typename... Inner>
3362	class FieldsAreMatcher {
3363	public:
3364	explicit FieldsAreMatcher(Inner... inner) : matchers_(std::move(inner)...) {}
3365
3366	template <typename Struct>
3367	operator Matcher<Struct>() const { // NOLINT
3368	return Matcher<Struct>(
3369	new FieldsAreMatcherImpl<const Struct&, IndexSequenceFor<Inner...>>(
3370	matchers_));
3371	}
3372
3373	private:
3374	std::tuple<Inner...> matchers_;
3375	};
3376
3377	// Implements ElementsAre() and ElementsAreArray().
3378	template <typename Container>
3379	class ElementsAreMatcherImpl : public MatcherInterface<Container> {
3380	public:
3381	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(Container) RawContainer;
3382	typedef internal::StlContainerView<RawContainer> View;
3383	typedef typename View::type StlContainer;
3384	typedef typename View::const_reference StlContainerReference;
3385
3386	// LLVM local change to support std::begin/std::end.
3387	//
3388	// typedef typename StlContainer::value_type Element;
3389	//
3390	typedef decltype(std::begin(
3391	std::declval<StlContainerReference>())) StlContainerConstIterator;
3392	typedef typename std::remove_reference<
3393	decltype(*std::declval<StlContainerConstIterator &>())>::type Element;
3394	// LLVM local change end.
3395
3396	// Constructs the matcher from a sequence of element values or
3397	// element matchers.
3398	template <typename InputIter>
3399	ElementsAreMatcherImpl(InputIter first, InputIter last) {
3400	while (first != last) {
3401	matchers_.push_back(MatcherCast<const Element&>(*first++));
3402	}
3403	}
3404
3405	// Describes what this matcher does.
3406	void DescribeTo(::std::ostream* os) const override {
3407	if (count() == 0) {
3408	*os << "is empty";
3409	} else if (count() == 1) {
3410	*os << "has 1 element that ";
3411	matchers_[0].DescribeTo(os);
3412	} else {
3413	*os << "has " << Elements(count: count()) << " where\n";
3414	for (size_t i = 0; i != count(); ++i) {
3415	*os << "element #" << i << " ";
3416	matchers_[i].DescribeTo(os);
3417	if (i + 1 < count()) {
3418	*os << ",\n";
3419	}
3420	}
3421	}
3422	}
3423
3424	// Describes what the negation of this matcher does.
3425	void DescribeNegationTo(::std::ostream* os) const override {
3426	if (count() == 0) {
3427	*os << "isn't empty";
3428	return;
3429	}
3430
3431	*os << "doesn't have " << Elements(count: count()) << ", or\n";
3432	for (size_t i = 0; i != count(); ++i) {
3433	*os << "element #" << i << " ";
3434	matchers_[i].DescribeNegationTo(os);
3435	if (i + 1 < count()) {
3436	*os << ", or\n";
3437	}
3438	}
3439	}
3440
3441	bool MatchAndExplain(Container container,
3442	MatchResultListener* listener) const override {
3443	// To work with stream-like "containers", we must only walk
3444	// through the elements in one pass.
3445
3446	const bool listener_interested = listener->IsInterested();
3447
3448	// explanations[i] is the explanation of the element at index i.
3449	::std::vector<std::string> explanations(count());
3450	StlContainerReference stl_container = View::ConstReference(container);
3451	// LLVM local change to support std::begin/std::end.
3452	//
3453	// auto it = stl_container.begin();
3454	//
3455	StlContainerConstIterator it = stl_container.begin();
3456	// LLVM local change end.
3457	size_t exam_pos = 0;
3458	bool mismatch_found = false; // Have we found a mismatched element yet?
3459
3460	// Go through the elements and matchers in pairs, until we reach
3461	// the end of either the elements or the matchers, or until we find a
3462	// mismatch.
3463	for (; it != stl_container.end() && exam_pos != count(); ++it, ++exam_pos) {
3464	bool match; // Does the current element match the current matcher?
3465	if (listener_interested) {
3466	StringMatchResultListener s;
3467	match = matchers_[exam_pos].MatchAndExplain(*it, &s);
3468	explanations[exam_pos] = s.str();
3469	} else {
3470	match = matchers_[exam_pos].Matches(*it);
3471	}
3472
3473	if (!match) {
3474	mismatch_found = true;
3475	break;
3476	}
3477	}
3478	// If mismatch_found is true, 'exam_pos' is the index of the mismatch.
3479
3480	// Find how many elements the actual container has. We avoid
3481	// calling size() s.t. this code works for stream-like "containers"
3482	// that don't define size().
3483	size_t actual_count = exam_pos;
3484	for (; it != stl_container.end(); ++it) {
3485	++actual_count;
3486	}
3487
3488	if (actual_count != count()) {
3489	// The element count doesn't match. If the container is empty,
3490	// there's no need to explain anything as Google Mock already
3491	// prints the empty container. Otherwise we just need to show
3492	// how many elements there actually are.
3493	if (listener_interested && (actual_count != 0)) {
3494	*listener << "which has " << Elements(count: actual_count);
3495	}
3496	return false;
3497	}
3498
3499	if (mismatch_found) {
3500	// The element count matches, but the exam_pos-th element doesn't match.
3501	if (listener_interested) {
3502	*listener << "whose element #" << exam_pos << " doesn't match";
3503	PrintIfNotEmpty(explanation: explanations[exam_pos], os: listener->stream());
3504	}
3505	return false;
3506	}
3507
3508	// Every element matches its expectation. We need to explain why
3509	// (the obvious ones can be skipped).
3510	if (listener_interested) {
3511	bool reason_printed = false;
3512	for (size_t i = 0; i != count(); ++i) {
3513	const std::string& s = explanations[i];
3514	if (!s.empty()) {
3515	if (reason_printed) {
3516	*listener << ",\nand ";
3517	}
3518	*listener << "whose element #" << i << " matches, " << s;
3519	reason_printed = true;
3520	}
3521	}
3522	}
3523	return true;
3524	}
3525
3526	private:
3527	static Message Elements(size_t count) {
3528	return Message() << count << (count == 1 ? " element" : " elements");
3529	}
3530
3531	size_t count() const { return matchers_.size(); }
3532
3533	::std::vector<Matcher<const Element&>> matchers_;
3534	};
3535
3536	// Connectivity matrix of (elements X matchers), in element-major order.
3537	// Initially, there are no edges.
3538	// Use NextGraph() to iterate over all possible edge configurations.
3539	// Use Randomize() to generate a random edge configuration.
3540	class GTEST_API_ MatchMatrix {
3541	public:
3542	MatchMatrix(size_t num_elements, size_t num_matchers)
3543	: num_elements_(num_elements),
3544	num_matchers_(num_matchers),
3545	matched_(num_elements_ * num_matchers_, 0) {}
3546
3547	size_t LhsSize() const { return num_elements_; }
3548	size_t RhsSize() const { return num_matchers_; }
3549	bool HasEdge(size_t ilhs, size_t irhs) const {
3550	return matched_[SpaceIndex(ilhs, irhs)] == 1;
3551	}
3552	void SetEdge(size_t ilhs, size_t irhs, bool b) {
3553	matched_[SpaceIndex(ilhs, irhs)] = b ? 1 : 0;
3554	}
3555
3556	// Treating the connectivity matrix as a (LhsSize()*RhsSize())-bit number,
3557	// adds 1 to that number; returns false if incrementing the graph left it
3558	// empty.
3559	bool NextGraph();
3560
3561	void Randomize();
3562
3563	std::string DebugString() const;
3564
3565	private:
3566	size_t SpaceIndex(size_t ilhs, size_t irhs) const {
3567	return ilhs * num_matchers_ + irhs;
3568	}
3569
3570	size_t num_elements_;
3571	size_t num_matchers_;
3572
3573	// Each element is a char interpreted as bool. They are stored as a
3574	// flattened array in lhs-major order, use 'SpaceIndex()' to translate
3575	// a (ilhs, irhs) matrix coordinate into an offset.
3576	::std::vector<char> matched_;
3577	};
3578
3579	typedef ::std::pair<size_t, size_t> ElementMatcherPair;
3580	typedef ::std::vector<ElementMatcherPair> ElementMatcherPairs;
3581
3582	// Returns a maximum bipartite matching for the specified graph 'g'.
3583	// The matching is represented as a vector of {element, matcher} pairs.
3584	GTEST_API_ ElementMatcherPairs FindMaxBipartiteMatching(const MatchMatrix& g);
3585
3586	struct UnorderedMatcherRequire {
3587	enum Flags {
3588	Superset = 1 << 0,
3589	Subset = 1 << 1,
3590	ExactMatch = Superset | Subset,
3591	};
3592	};
3593
3594	// Untyped base class for implementing UnorderedElementsAre. By
3595	// putting logic that's not specific to the element type here, we
3596	// reduce binary bloat and increase compilation speed.
3597	class GTEST_API_ UnorderedElementsAreMatcherImplBase {
3598	protected:
3599	explicit UnorderedElementsAreMatcherImplBase(
3600	UnorderedMatcherRequire::Flags matcher_flags)
3601	: match_flags_(matcher_flags) {}
3602
3603	// A vector of matcher describers, one for each element matcher.
3604	// Does not own the describers (and thus can be used only when the
3605	// element matchers are alive).
3606	typedef ::std::vector<const MatcherDescriberInterface*> MatcherDescriberVec;
3607
3608	// Describes this UnorderedElementsAre matcher.
3609	void DescribeToImpl(::std::ostream* os) const;
3610
3611	// Describes the negation of this UnorderedElementsAre matcher.
3612	void DescribeNegationToImpl(::std::ostream* os) const;
3613
3614	bool VerifyMatchMatrix(const ::std::vector<std::string>& element_printouts,
3615	const MatchMatrix& matrix,
3616	MatchResultListener* listener) const;
3617
3618	bool FindPairing(const MatchMatrix& matrix,
3619	MatchResultListener* listener) const;
3620
3621	MatcherDescriberVec& matcher_describers() { return matcher_describers_; }
3622
3623	static Message Elements(size_t n) {
3624	return Message() << n << " element" << (n == 1 ? "" : "s");
3625	}
3626
3627	UnorderedMatcherRequire::Flags match_flags() const { return match_flags_; }
3628
3629	private:
3630	UnorderedMatcherRequire::Flags match_flags_;
3631	MatcherDescriberVec matcher_describers_;
3632	};
3633
3634	// Implements UnorderedElementsAre, UnorderedElementsAreArray, IsSubsetOf, and
3635	// IsSupersetOf.
3636	template <typename Container>
3637	class UnorderedElementsAreMatcherImpl
3638	: public MatcherInterface<Container>,
3639	public UnorderedElementsAreMatcherImplBase {
3640	public:
3641	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(Container) RawContainer;
3642	typedef internal::StlContainerView<RawContainer> View;
3643	typedef typename View::type StlContainer;
3644	typedef typename View::const_reference StlContainerReference;
3645	// LLVM local change to support std::begin/std::end.
3646	//
3647	// typedef typename StlContainer::value_type Element;
3648	typedef decltype(std::begin(
3649	std::declval<StlContainerReference>())) StlContainerConstIterator;
3650	typedef typename std::remove_reference<
3651	decltype(*std::declval<StlContainerConstIterator &>())>::type Element;
3652	// LLVM local change end.
3653	template <typename InputIter>
3654	UnorderedElementsAreMatcherImpl(UnorderedMatcherRequire::Flags matcher_flags,
3655	InputIter first, InputIter last)
3656	: UnorderedElementsAreMatcherImplBase(matcher_flags) {
3657	for (; first != last; ++first) {
3658	matchers_.push_back(MatcherCast<const Element&>(*first));
3659	}
3660	for (const auto& m : matchers_) {
3661	matcher_describers().push_back(m.GetDescriber());
3662	}
3663	}
3664
3665	// Describes what this matcher does.
3666	void DescribeTo(::std::ostream* os) const override {
3667	return UnorderedElementsAreMatcherImplBase::DescribeToImpl(os);
3668	}
3669
3670	// Describes what the negation of this matcher does.
3671	void DescribeNegationTo(::std::ostream* os) const override {
3672	return UnorderedElementsAreMatcherImplBase::DescribeNegationToImpl(os);
3673	}
3674
3675	bool MatchAndExplain(Container container,
3676	MatchResultListener* listener) const override {
3677	StlContainerReference stl_container = View::ConstReference(container);
3678	::std::vector<std::string> element_printouts;
3679	MatchMatrix matrix =
3680	AnalyzeElements(stl_container.begin(), stl_container.end(),
3681	&element_printouts, listener);
3682
3683	return VerifyMatchMatrix(element_printouts, matrix, listener) &&
3684	FindPairing(matrix, listener);
3685	}
3686
3687	private:
3688	template <typename ElementIter>
3689	MatchMatrix AnalyzeElements(ElementIter elem_first, ElementIter elem_last,
3690	::std::vector<std::string>* element_printouts,
3691	MatchResultListener* listener) const {
3692	element_printouts->clear();
3693	::std::vector<char> did_match;
3694	size_t num_elements = 0;
3695	DummyMatchResultListener dummy;
3696	for (; elem_first != elem_last; ++num_elements, ++elem_first) {
3697	if (listener->IsInterested()) {
3698	element_printouts->push_back(PrintToString(*elem_first));
3699	}
3700	for (size_t irhs = 0; irhs != matchers_.size(); ++irhs) {
3701	did_match.push_back(
3702	matchers_[irhs].MatchAndExplain(*elem_first, &dummy));
3703	}
3704	}
3705
3706	MatchMatrix matrix(num_elements, matchers_.size());
3707	::std::vector<char>::const_iterator did_match_iter = did_match.begin();
3708	for (size_t ilhs = 0; ilhs != num_elements; ++ilhs) {
3709	for (size_t irhs = 0; irhs != matchers_.size(); ++irhs) {
3710	matrix.SetEdge(ilhs, irhs, b: *did_match_iter++ != 0);
3711	}
3712	}
3713	return matrix;
3714	}
3715
3716	::std::vector<Matcher<const Element&>> matchers_;
3717	};
3718
3719	// Functor for use in TransformTuple.
3720	// Performs MatcherCast<Target> on an input argument of any type.
3721	template <typename Target>
3722	struct CastAndAppendTransform {
3723	template <typename Arg>
3724	Matcher<Target> operator()(const Arg& a) const {
3725	return MatcherCast<Target>(a);
3726	}
3727	};
3728
3729	// Implements UnorderedElementsAre.
3730	template <typename MatcherTuple>
3731	class UnorderedElementsAreMatcher {
3732	public:
3733	explicit UnorderedElementsAreMatcher(const MatcherTuple& args)
3734	: matchers_(args) {}
3735
3736	template <typename Container>
3737	operator Matcher<Container>() const {
3738	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(Container) RawContainer;
3739	// LLVM local change to support std::begin/std::end.
3740	//
3741	// typedef typename internal::StlContainerView<RawContainer>::type View;
3742	// typedef typename View::value_type Element;
3743	//
3744	typedef internal::StlContainerView<RawContainer> View;
3745	typedef typename View::const_reference StlContainerReference;
3746	typedef decltype(std::begin(
3747	std::declval<StlContainerReference>())) StlContainerConstIterator;
3748	typedef typename std::remove_reference<
3749	decltype(*std::declval<StlContainerConstIterator &>())>::type Element;
3750	// LLVM local change end.
3751	typedef ::std::vector<Matcher<const Element&>> MatcherVec;
3752	MatcherVec matchers;
3753	matchers.reserve(::std::tuple_size<MatcherTuple>::value);
3754	TransformTupleValues(CastAndAppendTransform<const Element&>(), matchers_,
3755	::std::back_inserter(matchers));
3756	return Matcher<Container>(
3757	new UnorderedElementsAreMatcherImpl<const Container&>(
3758	UnorderedMatcherRequire::ExactMatch, matchers.begin(),
3759	matchers.end()));
3760	}
3761
3762	private:
3763	const MatcherTuple matchers_;
3764	};
3765
3766	// Implements ElementsAre.
3767	template <typename MatcherTuple>
3768	class ElementsAreMatcher {
3769	public:
3770	explicit ElementsAreMatcher(const MatcherTuple& args) : matchers_(args) {}
3771
3772	template <typename Container>
3773	operator Matcher<Container>() const {
3774	static_assert(
3775	!IsHashTable<GTEST_REMOVE_REFERENCE_AND_CONST_(Container)>::value ||
3776	::std::tuple_size<MatcherTuple>::value < 2,
3777	"use UnorderedElementsAre with hash tables");
3778
3779	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(Container) RawContainer;
3780	// LLVM local change to support std::begin/std::end.
3781	//
3782	// typedef typename internal::StlContainerView<RawContainer>::type View;
3783	// typedef typename View::value_type Element;
3784	//
3785	typedef internal::StlContainerView<RawContainer> View;
3786	typedef typename View::const_reference StlContainerReference;
3787	typedef decltype(std::begin(
3788	std::declval<StlContainerReference>())) StlContainerConstIterator;
3789	typedef typename std::remove_reference<
3790	decltype(*std::declval<StlContainerConstIterator &>())>::type Element;
3791	// LLVM local change end.
3792	typedef ::std::vector<Matcher<const Element&>> MatcherVec;
3793	MatcherVec matchers;
3794	matchers.reserve(::std::tuple_size<MatcherTuple>::value);
3795	TransformTupleValues(CastAndAppendTransform<const Element&>(), matchers_,
3796	::std::back_inserter(matchers));
3797	return Matcher<Container>(new ElementsAreMatcherImpl<const Container&>(
3798	matchers.begin(), matchers.end()));
3799	}
3800
3801	private:
3802	const MatcherTuple matchers_;
3803	};
3804
3805	// Implements UnorderedElementsAreArray(), IsSubsetOf(), and IsSupersetOf().
3806	template <typename T>
3807	class UnorderedElementsAreArrayMatcher {
3808	public:
3809	template <typename Iter>
3810	UnorderedElementsAreArrayMatcher(UnorderedMatcherRequire::Flags match_flags,
3811	Iter first, Iter last)
3812	: match_flags_(match_flags), matchers_(first, last) {}
3813
3814	template <typename Container>
3815	operator Matcher<Container>() const {
3816	return Matcher<Container>(
3817	new UnorderedElementsAreMatcherImpl<const Container&>(
3818	match_flags_, matchers_.begin(), matchers_.end()));
3819	}
3820
3821	private:
3822	UnorderedMatcherRequire::Flags match_flags_;
3823	::std::vector<T> matchers_;
3824	};
3825
3826	// Implements ElementsAreArray().
3827	template <typename T>
3828	class ElementsAreArrayMatcher {
3829	public:
3830	template <typename Iter>
3831	ElementsAreArrayMatcher(Iter first, Iter last) : matchers_(first, last) {}
3832
3833	template <typename Container>
3834	operator Matcher<Container>() const {
3835	static_assert(
3836	!IsHashTable<GTEST_REMOVE_REFERENCE_AND_CONST_(Container)>::value,
3837	"use UnorderedElementsAreArray with hash tables");
3838
3839	return Matcher<Container>(new ElementsAreMatcherImpl<const Container&>(
3840	matchers_.begin(), matchers_.end()));
3841	}
3842
3843	private:
3844	const ::std::vector<T> matchers_;
3845	};
3846
3847	// Given a 2-tuple matcher tm of type Tuple2Matcher and a value second
3848	// of type Second, BoundSecondMatcher<Tuple2Matcher, Second>(tm,
3849	// second) is a polymorphic matcher that matches a value x if and only if
3850	// tm matches tuple (x, second). Useful for implementing
3851	// UnorderedPointwise() in terms of UnorderedElementsAreArray().
3852	//
3853	// BoundSecondMatcher is copyable and assignable, as we need to put
3854	// instances of this class in a vector when implementing
3855	// UnorderedPointwise().
3856	template <typename Tuple2Matcher, typename Second>
3857	class BoundSecondMatcher {
3858	public:
3859	BoundSecondMatcher(const Tuple2Matcher& tm, const Second& second)
3860	: tuple2_matcher_(tm), second_value_(second) {}
3861
3862	BoundSecondMatcher(const BoundSecondMatcher& other) = default;
3863
3864	template <typename T>
3865	operator Matcher<T>() const {
3866	return MakeMatcher(new Impl<T>(tuple2_matcher_, second_value_));
3867	}
3868
3869	// We have to define this for UnorderedPointwise() to compile in
3870	// C++98 mode, as it puts BoundSecondMatcher instances in a vector,
3871	// which requires the elements to be assignable in C++98. The
3872	// compiler cannot generate the operator= for us, as Tuple2Matcher
3873	// and Second may not be assignable.
3874	//
3875	// However, this should never be called, so the implementation just
3876	// need to assert.
3877	void operator=(const BoundSecondMatcher& /*rhs*/) {
3878	GTEST_LOG_(FATAL) << "BoundSecondMatcher should never be assigned.";
3879	}
3880
3881	private:
3882	template <typename T>
3883	class Impl : public MatcherInterface<T> {
3884	public:
3885	typedef ::std::tuple<T, Second> ArgTuple;
3886
3887	Impl(const Tuple2Matcher& tm, const Second& second)
3888	: mono_tuple2_matcher_(SafeMatcherCast<const ArgTuple&>(tm)),
3889	second_value_(second) {}
3890
3891	void DescribeTo(::std::ostream* os) const override {
3892	*os << "and ";
3893	UniversalPrint(second_value_, os);
3894	*os << " ";
3895	mono_tuple2_matcher_.DescribeTo(os);
3896	}
3897
3898	bool MatchAndExplain(T x, MatchResultListener* listener) const override {
3899	return mono_tuple2_matcher_.MatchAndExplain(ArgTuple(x, second_value_),
3900	listener);
3901	}
3902
3903	private:
3904	const Matcher<const ArgTuple&> mono_tuple2_matcher_;
3905	const Second second_value_;
3906	};
3907
3908	const Tuple2Matcher tuple2_matcher_;
3909	const Second second_value_;
3910	};
3911
3912	// Given a 2-tuple matcher tm and a value second,
3913	// MatcherBindSecond(tm, second) returns a matcher that matches a
3914	// value x if and only if tm matches tuple (x, second). Useful for
3915	// implementing UnorderedPointwise() in terms of UnorderedElementsAreArray().
3916	template <typename Tuple2Matcher, typename Second>
3917	BoundSecondMatcher<Tuple2Matcher, Second> MatcherBindSecond(
3918	const Tuple2Matcher& tm, const Second& second) {
3919	return BoundSecondMatcher<Tuple2Matcher, Second>(tm, second);
3920	}
3921
3922	// Returns the description for a matcher defined using the MATCHER*()
3923	// macro where the user-supplied description string is "", if
3924	// 'negation' is false; otherwise returns the description of the
3925	// negation of the matcher. 'param_values' contains a list of strings
3926	// that are the print-out of the matcher's parameters.
3927	GTEST_API_ std::string FormatMatcherDescription(
3928	bool negation, const char* matcher_name,
3929	const std::vector<const char*>& param_names, const Strings& param_values);
3930
3931	// Implements a matcher that checks the value of a optional<> type variable.
3932	template <typename ValueMatcher>
3933	class OptionalMatcher {
3934	public:
3935	explicit OptionalMatcher(const ValueMatcher& value_matcher)
3936	: value_matcher_(value_matcher) {}
3937
3938	template <typename Optional>
3939	operator Matcher<Optional>() const {
3940	return Matcher<Optional>(new Impl<const Optional&>(value_matcher_));
3941	}
3942
3943	template <typename Optional>
3944	class Impl : public MatcherInterface<Optional> {
3945	public:
3946	typedef GTEST_REMOVE_REFERENCE_AND_CONST_(Optional) OptionalView;
3947	typedef typename OptionalView::value_type ValueType;
3948	explicit Impl(const ValueMatcher& value_matcher)
3949	: value_matcher_(MatcherCast<ValueType>(value_matcher)) {}
3950
3951	void DescribeTo(::std::ostream* os) const override {
3952	*os << "value ";
3953	value_matcher_.DescribeTo(os);
3954	}
3955
3956	void DescribeNegationTo(::std::ostream* os) const override {
3957	*os << "value ";
3958	value_matcher_.DescribeNegationTo(os);
3959	}
3960
3961	bool MatchAndExplain(Optional optional,
3962	MatchResultListener* listener) const override {
3963	if (!optional) {
3964	*listener << "which is not engaged";
3965	return false;
3966	}
3967	const ValueType& value = *optional;
3968	StringMatchResultListener value_listener;
3969	const bool match = value_matcher_.MatchAndExplain(value, &value_listener);
3970	*listener << "whose value " << PrintToString(value)
3971	<< (match ? " matches" : " doesn't match");
3972	PrintIfNotEmpty(explanation: value_listener.str(), os: listener->stream());
3973	return match;
3974	}
3975
3976	private:
3977	const Matcher<ValueType> value_matcher_;
3978	};
3979
3980	private:
3981	const ValueMatcher value_matcher_;
3982	};
3983
3984	namespace variant_matcher {
3985	// Overloads to allow VariantMatcher to do proper ADL lookup.
3986	template <typename T>
3987	void holds_alternative() {}
3988	template <typename T>
3989	void get() {}
3990
3991	// Implements a matcher that checks the value of a variant<> type variable.
3992	template <typename T>
3993	class VariantMatcher {
3994	public:
3995	explicit VariantMatcher(::testing::Matcher<const T&> matcher)
3996	: matcher_(std::move(matcher)) {}
3997
3998	template <typename Variant>
3999	bool MatchAndExplain(const Variant& value,
4000	::testing::MatchResultListener* listener) const {
4001	using std::get;
4002	if (!listener->IsInterested()) {
4003	return holds_alternative<T>(value) && matcher_.Matches(get<T>(value));
4004	}
4005
4006	if (!holds_alternative<T>(value)) {
4007	*listener << "whose value is not of type '" << GetTypeName() << "'";
4008	return false;
4009	}
4010
4011	const T& elem = get<T>(value);
4012	StringMatchResultListener elem_listener;
4013	const bool match = matcher_.MatchAndExplain(elem, &elem_listener);
4014	*listener << "whose value " << PrintToString(elem)
4015	<< (match ? " matches" : " doesn't match");
4016	PrintIfNotEmpty(explanation: elem_listener.str(), os: listener->stream());
4017	return match;
4018	}
4019
4020	void DescribeTo(std::ostream* os) const {
4021	*os << "is a variant<> with value of type '" << GetTypeName()
4022	<< "' and the value ";
4023	matcher_.DescribeTo(os);
4024	}
4025
4026	void DescribeNegationTo(std::ostream* os) const {
4027	*os << "is a variant<> with value of type other than '" << GetTypeName()
4028	<< "' or the value ";
4029	matcher_.DescribeNegationTo(os);
4030	}
4031
4032	private:
4033	static std::string GetTypeName() {
4034	#if GTEST_HAS_RTTI
4035	GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(
4036	return internal::GetTypeName<T>());
4037	#endif
4038	return "the element type";
4039	}
4040
4041	const ::testing::Matcher<const T&> matcher_;
4042	};
4043
4044	} // namespace variant_matcher
4045
4046	namespace any_cast_matcher {
4047
4048	// Overloads to allow AnyCastMatcher to do proper ADL lookup.
4049	template <typename T>
4050	void any_cast() {}
4051
4052	// Implements a matcher that any_casts the value.
4053	template <typename T>
4054	class AnyCastMatcher {
4055	public:
4056	explicit AnyCastMatcher(const ::testing::Matcher<const T&>& matcher)
4057	: matcher_(matcher) {}
4058
4059	template <typename AnyType>
4060	bool MatchAndExplain(const AnyType& value,
4061	::testing::MatchResultListener* listener) const {
4062	if (!listener->IsInterested()) {
4063	const T* ptr = any_cast<T>(&value);
4064	return ptr != nullptr && matcher_.Matches(*ptr);
4065	}
4066
4067	const T* elem = any_cast<T>(&value);
4068	if (elem == nullptr) {
4069	*listener << "whose value is not of type '" << GetTypeName() << "'";
4070	return false;
4071	}
4072
4073	StringMatchResultListener elem_listener;
4074	const bool match = matcher_.MatchAndExplain(*elem, &elem_listener);
4075	*listener << "whose value " << PrintToString(*elem)
4076	<< (match ? " matches" : " doesn't match");
4077	PrintIfNotEmpty(explanation: elem_listener.str(), os: listener->stream());
4078	return match;
4079	}
4080
4081	void DescribeTo(std::ostream* os) const {
4082	*os << "is an 'any' type with value of type '" << GetTypeName()
4083	<< "' and the value ";
4084	matcher_.DescribeTo(os);
4085	}
4086
4087	void DescribeNegationTo(std::ostream* os) const {
4088	*os << "is an 'any' type with value of type other than '" << GetTypeName()
4089	<< "' or the value ";
4090	matcher_.DescribeNegationTo(os);
4091	}
4092
4093	private:
4094	static std::string GetTypeName() {
4095	#if GTEST_HAS_RTTI
4096	GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(
4097	return internal::GetTypeName<T>());
4098	#endif
4099	return "the element type";
4100	}
4101
4102	const ::testing::Matcher<const T&> matcher_;
4103	};
4104
4105	} // namespace any_cast_matcher
4106
4107	// Implements the Args() matcher.
4108	template <class ArgsTuple, size_t... k>
4109	class ArgsMatcherImpl : public MatcherInterface<ArgsTuple> {
4110	public:
4111	using RawArgsTuple = typename std::decay<ArgsTuple>::type;
4112	using SelectedArgs =
4113	std::tuple<typename std::tuple_element<k, RawArgsTuple>::type...>;
4114	using MonomorphicInnerMatcher = Matcher<const SelectedArgs&>;
4115
4116	template <typename InnerMatcher>
4117	explicit ArgsMatcherImpl(const InnerMatcher& inner_matcher)
4118	: inner_matcher_(SafeMatcherCast<const SelectedArgs&>(inner_matcher)) {}
4119
4120	bool MatchAndExplain(ArgsTuple args,
4121	MatchResultListener* listener) const override {
4122	// Workaround spurious C4100 on MSVC<=15.7 when k is empty.
4123	(void)args;
4124	const SelectedArgs& selected_args =
4125	std::forward_as_tuple(std::get<k>(args)...);
4126	if (!listener->IsInterested()) return inner_matcher_.Matches(selected_args);
4127
4128	PrintIndices(os: listener->stream());
4129	*listener << "are " << PrintToString(selected_args);
4130
4131	StringMatchResultListener inner_listener;
4132	const bool match =
4133	inner_matcher_.MatchAndExplain(selected_args, &inner_listener);
4134	PrintIfNotEmpty(explanation: inner_listener.str(), os: listener->stream());
4135	return match;
4136	}
4137
4138	void DescribeTo(::std::ostream* os) const override {
4139	*os << "are a tuple ";
4140	PrintIndices(os);
4141	inner_matcher_.DescribeTo(os);
4142	}
4143
4144	void DescribeNegationTo(::std::ostream* os) const override {
4145	*os << "are a tuple ";
4146	PrintIndices(os);
4147	inner_matcher_.DescribeNegationTo(os);
4148	}
4149
4150	private:
4151	// Prints the indices of the selected fields.
4152	static void PrintIndices(::std::ostream* os) {
4153	*os << "whose fields (";
4154	const char* sep = "";
4155	// Workaround spurious C4189 on MSVC<=15.7 when k is empty.
4156	(void)sep;
4157	// The static_cast to void is needed to silence Clang's -Wcomma warning.
4158	// This pattern looks suspiciously like we may have mismatched parentheses
4159	// and may have been trying to use the first operation of the comma operator
4160	// as a member of the array, so Clang warns that we may have made a mistake.
4161	const char* dummy[] = {
4162	"", (static_cast<void>(*os << sep << "#" << k), sep = ", ")...};
4163	(void)dummy;
4164	*os << ") ";
4165	}
4166
4167	MonomorphicInnerMatcher inner_matcher_;
4168	};
4169
4170	template <class InnerMatcher, size_t... k>
4171	class ArgsMatcher {
4172	public:
4173	explicit ArgsMatcher(InnerMatcher inner_matcher)
4174	: inner_matcher_(std::move(inner_matcher)) {}
4175
4176	template <typename ArgsTuple>
4177	operator Matcher<ArgsTuple>() const { // NOLINT
4178	return MakeMatcher(new ArgsMatcherImpl<ArgsTuple, k...>(inner_matcher_));
4179	}
4180
4181	private:
4182	InnerMatcher inner_matcher_;
4183	};
4184
4185	} // namespace internal
4186
4187	// ElementsAreArray(iterator_first, iterator_last)
4188	// ElementsAreArray(pointer, count)
4189	// ElementsAreArray(array)
4190	// ElementsAreArray(container)
4191	// ElementsAreArray({ e1, e2, ..., en })
4192	//
4193	// The ElementsAreArray() functions are like ElementsAre(...), except
4194	// that they are given a homogeneous sequence rather than taking each
4195	// element as a function argument. The sequence can be specified as an
4196	// array, a pointer and count, a vector, an initializer list, or an
4197	// STL iterator range. In each of these cases, the underlying sequence
4198	// can be either a sequence of values or a sequence of matchers.
4199	//
4200	// All forms of ElementsAreArray() make a copy of the input matcher sequence.
4201
4202	template <typename Iter>
4203	inline internal::ElementsAreArrayMatcher<
4204	typename ::std::iterator_traits<Iter>::value_type>
4205	ElementsAreArray(Iter first, Iter last) {
4206	typedef typename ::std::iterator_traits<Iter>::value_type T;
4207	return internal::ElementsAreArrayMatcher<T>(first, last);
4208	}
4209
4210	template <typename T>
4211	inline auto ElementsAreArray(const T* pointer, size_t count)
4212	-> decltype(ElementsAreArray(pointer, pointer + count)) {
4213	return ElementsAreArray(pointer, pointer + count);
4214	}
4215
4216	template <typename T, size_t N>
4217	inline auto ElementsAreArray(const T (&array)[N])
4218	-> decltype(ElementsAreArray(array, N)) {
4219	return ElementsAreArray(array, N);
4220	}
4221
4222	template <typename Container>
4223	inline auto ElementsAreArray(const Container& container)
4224	-> decltype(ElementsAreArray(container.begin(), container.end())) {
4225	return ElementsAreArray(container.begin(), container.end());
4226	}
4227
4228	template <typename T>
4229	inline auto ElementsAreArray(::std::initializer_list<T> xs)
4230	-> decltype(ElementsAreArray(xs.begin(), xs.end())) {
4231	return ElementsAreArray(xs.begin(), xs.end());
4232	}
4233
4234	// UnorderedElementsAreArray(iterator_first, iterator_last)
4235	// UnorderedElementsAreArray(pointer, count)
4236	// UnorderedElementsAreArray(array)
4237	// UnorderedElementsAreArray(container)
4238	// UnorderedElementsAreArray({ e1, e2, ..., en })
4239	//
4240	// UnorderedElementsAreArray() verifies that a bijective mapping onto a
4241	// collection of matchers exists.
4242	//
4243	// The matchers can be specified as an array, a pointer and count, a container,
4244	// an initializer list, or an STL iterator range. In each of these cases, the
4245	// underlying matchers can be either values or matchers.
4246
4247	template <typename Iter>
4248	inline internal::UnorderedElementsAreArrayMatcher<
4249	typename ::std::iterator_traits<Iter>::value_type>
4250	UnorderedElementsAreArray(Iter first, Iter last) {
4251	typedef typename ::std::iterator_traits<Iter>::value_type T;
4252	return internal::UnorderedElementsAreArrayMatcher<T>(
4253	internal::UnorderedMatcherRequire::ExactMatch, first, last);
4254	}
4255
4256	template <typename T>
4257	inline internal::UnorderedElementsAreArrayMatcher<T> UnorderedElementsAreArray(
4258	const T* pointer, size_t count) {
4259	return UnorderedElementsAreArray(pointer, pointer + count);
4260	}
4261
4262	template <typename T, size_t N>
4263	inline internal::UnorderedElementsAreArrayMatcher<T> UnorderedElementsAreArray(
4264	const T (&array)[N]) {
4265	return UnorderedElementsAreArray(array, N);
4266	}
4267
4268	template <typename Container>
4269	inline internal::UnorderedElementsAreArrayMatcher<
4270	typename Container::value_type>
4271	UnorderedElementsAreArray(const Container& container) {
4272	return UnorderedElementsAreArray(container.begin(), container.end());
4273	}
4274
4275	template <typename T>
4276	inline internal::UnorderedElementsAreArrayMatcher<T> UnorderedElementsAreArray(
4277	::std::initializer_list<T> xs) {
4278	return UnorderedElementsAreArray(xs.begin(), xs.end());
4279	}
4280
4281	// _ is a matcher that matches anything of any type.
4282	//
4283	// This definition is fine as:
4284	//
4285	// 1. The C++ standard permits using the name _ in a namespace that
4286	// is not the global namespace or ::std.
4287	// 2. The AnythingMatcher class has no data member or constructor,
4288	// so it's OK to create global variables of this type.
4289	// 3. c-style has approved of using _ in this case.
4290	const internal::AnythingMatcher _ = {};
4291	// Creates a matcher that matches any value of the given type T.
4292	template <typename T>
4293	inline Matcher<T> A() {
4294	return _;
4295	}
4296
4297	// Creates a matcher that matches any value of the given type T.
4298	template <typename T>
4299	inline Matcher<T> An() {
4300	return _;
4301	}
4302
4303	template <typename T, typename M>
4304	Matcher<T> internal::MatcherCastImpl<T, M>::CastImpl(
4305	const M& value, std::false_type /* convertible_to_matcher */,
4306	std::false_type /* convertible_to_T */) {
4307	return Eq(value);
4308	}
4309
4310	// Creates a polymorphic matcher that matches any NULL pointer.
4311	inline PolymorphicMatcher<internal::IsNullMatcher> IsNull() {
4312	return MakePolymorphicMatcher(impl: internal::IsNullMatcher());
4313	}
4314
4315	// Creates a polymorphic matcher that matches any non-NULL pointer.
4316	// This is convenient as Not(NULL) doesn't compile (the compiler
4317	// thinks that that expression is comparing a pointer with an integer).
4318	inline PolymorphicMatcher<internal::NotNullMatcher> NotNull() {
4319	return MakePolymorphicMatcher(impl: internal::NotNullMatcher());
4320	}
4321
4322	// Creates a polymorphic matcher that matches any argument that
4323	// references variable x.
4324	template <typename T>
4325	inline internal::RefMatcher<T&> Ref(T& x) { // NOLINT
4326	return internal::RefMatcher<T&>(x);
4327	}
4328
4329	// Creates a polymorphic matcher that matches any NaN floating point.
4330	inline PolymorphicMatcher<internal::IsNanMatcher> IsNan() {
4331	return MakePolymorphicMatcher(impl: internal::IsNanMatcher());
4332	}
4333
4334	// Creates a matcher that matches any double argument approximately
4335	// equal to rhs, where two NANs are considered unequal.
4336	inline internal::FloatingEqMatcher<double> DoubleEq(double rhs) {
4337	return internal::FloatingEqMatcher<double>(rhs, false);
4338	}
4339
4340	// Creates a matcher that matches any double argument approximately
4341	// equal to rhs, including NaN values when rhs is NaN.
4342	inline internal::FloatingEqMatcher<double> NanSensitiveDoubleEq(double rhs) {
4343	return internal::FloatingEqMatcher<double>(rhs, true);
4344	}
4345
4346	// Creates a matcher that matches any double argument approximately equal to
4347	// rhs, up to the specified max absolute error bound, where two NANs are
4348	// considered unequal. The max absolute error bound must be non-negative.
4349	inline internal::FloatingEqMatcher<double> DoubleNear(double rhs,
4350	double max_abs_error) {
4351	return internal::FloatingEqMatcher<double>(rhs, false, max_abs_error);
4352	}
4353
4354	// Creates a matcher that matches any double argument approximately equal to
4355	// rhs, up to the specified max absolute error bound, including NaN values when
4356	// rhs is NaN. The max absolute error bound must be non-negative.
4357	inline internal::FloatingEqMatcher<double> NanSensitiveDoubleNear(
4358	double rhs, double max_abs_error) {
4359	return internal::FloatingEqMatcher<double>(rhs, true, max_abs_error);
4360	}
4361
4362	// Creates a matcher that matches any float argument approximately
4363	// equal to rhs, where two NANs are considered unequal.
4364	inline internal::FloatingEqMatcher<float> FloatEq(float rhs) {
4365	return internal::FloatingEqMatcher<float>(rhs, false);
4366	}
4367
4368	// Creates a matcher that matches any float argument approximately
4369	// equal to rhs, including NaN values when rhs is NaN.
4370	inline internal::FloatingEqMatcher<float> NanSensitiveFloatEq(float rhs) {
4371	return internal::FloatingEqMatcher<float>(rhs, true);
4372	}
4373
4374	// Creates a matcher that matches any float argument approximately equal to
4375	// rhs, up to the specified max absolute error bound, where two NANs are
4376	// considered unequal. The max absolute error bound must be non-negative.
4377	inline internal::FloatingEqMatcher<float> FloatNear(float rhs,
4378	float max_abs_error) {
4379	return internal::FloatingEqMatcher<float>(rhs, false, max_abs_error);
4380	}
4381
4382	// Creates a matcher that matches any float argument approximately equal to
4383	// rhs, up to the specified max absolute error bound, including NaN values when
4384	// rhs is NaN. The max absolute error bound must be non-negative.
4385	inline internal::FloatingEqMatcher<float> NanSensitiveFloatNear(
4386	float rhs, float max_abs_error) {
4387	return internal::FloatingEqMatcher<float>(rhs, true, max_abs_error);
4388	}
4389
4390	// Creates a matcher that matches a pointer (raw or smart) that points
4391	// to a value that matches inner_matcher.
4392	template <typename InnerMatcher>
4393	inline internal::PointeeMatcher<InnerMatcher> Pointee(
4394	const InnerMatcher& inner_matcher) {
4395	return internal::PointeeMatcher<InnerMatcher>(inner_matcher);
4396	}
4397
4398	#if GTEST_HAS_RTTI
4399	// Creates a matcher that matches a pointer or reference that matches
4400	// inner_matcher when dynamic_cast<To> is applied.
4401	// The result of dynamic_cast<To> is forwarded to the inner matcher.
4402	// If To is a pointer and the cast fails, the inner matcher will receive NULL.
4403	// If To is a reference and the cast fails, this matcher returns false
4404	// immediately.
4405	template <typename To>
4406	inline PolymorphicMatcher<internal::WhenDynamicCastToMatcher<To>>
4407	WhenDynamicCastTo(const Matcher<To>& inner_matcher) {
4408	return MakePolymorphicMatcher(
4409	internal::WhenDynamicCastToMatcher<To>(inner_matcher));
4410	}
4411	#endif // GTEST_HAS_RTTI
4412
4413	// Creates a matcher that matches an object whose given field matches
4414	// 'matcher'. For example,
4415	// Field(&Foo::number, Ge(5))
4416	// matches a Foo object x if and only if x.number >= 5.
4417	template <typename Class, typename FieldType, typename FieldMatcher>
4418	inline PolymorphicMatcher<internal::FieldMatcher<Class, FieldType>> Field(
4419	FieldType Class::*field, const FieldMatcher& matcher) {
4420	return MakePolymorphicMatcher(internal::FieldMatcher<Class, FieldType>(
4421	field, MatcherCast<const FieldType&>(matcher)));
4422	// The call to MatcherCast() is required for supporting inner
4423	// matchers of compatible types. For example, it allows
4424	// Field(&Foo::bar, m)
4425	// to compile where bar is an int32 and m is a matcher for int64.
4426	}
4427
4428	// Same as Field() but also takes the name of the field to provide better error
4429	// messages.
4430	template <typename Class, typename FieldType, typename FieldMatcher>
4431	inline PolymorphicMatcher<internal::FieldMatcher<Class, FieldType>> Field(
4432	const std::string& field_name, FieldType Class::*field,
4433	const FieldMatcher& matcher) {
4434	return MakePolymorphicMatcher(internal::FieldMatcher<Class, FieldType>(
4435	field_name, field, MatcherCast<const FieldType&>(matcher)));
4436	}
4437
4438	// Creates a matcher that matches an object whose given property
4439	// matches 'matcher'. For example,
4440	// Property(&Foo::str, StartsWith("hi"))
4441	// matches a Foo object x if and only if x.str() starts with "hi".
4442	template <typename Class, typename PropertyType, typename PropertyMatcher>
4443	inline PolymorphicMatcher<internal::PropertyMatcher<
4444	Class, PropertyType, PropertyType (Class::*)() const>>
4445	Property(PropertyType (Class::*property)() const,
4446	const PropertyMatcher& matcher) {
4447	return MakePolymorphicMatcher(
4448	internal::PropertyMatcher<Class, PropertyType,
4449	PropertyType (Class::*)() const>(
4450	property, MatcherCast<const PropertyType&>(matcher)));
4451	// The call to MatcherCast() is required for supporting inner
4452	// matchers of compatible types. For example, it allows
4453	// Property(&Foo::bar, m)
4454	// to compile where bar() returns an int32 and m is a matcher for int64.
4455	}
4456
4457	// Same as Property() above, but also takes the name of the property to provide
4458	// better error messages.
4459	template <typename Class, typename PropertyType, typename PropertyMatcher>
4460	inline PolymorphicMatcher<internal::PropertyMatcher<
4461	Class, PropertyType, PropertyType (Class::*)() const>>
4462	Property(const std::string& property_name,
4463	PropertyType (Class::*property)() const,
4464	const PropertyMatcher& matcher) {
4465	return MakePolymorphicMatcher(
4466	internal::PropertyMatcher<Class, PropertyType,
4467	PropertyType (Class::*)() const>(
4468	property_name, property, MatcherCast<const PropertyType&>(matcher)));
4469	}
4470
4471	// The same as above but for reference-qualified member functions.
4472	template <typename Class, typename PropertyType, typename PropertyMatcher>
4473	inline PolymorphicMatcher<internal::PropertyMatcher<
4474	Class, PropertyType, PropertyType (Class::*)() const&>>
4475	Property(PropertyType (Class::*property)() const&,
4476	const PropertyMatcher& matcher) {
4477	return MakePolymorphicMatcher(
4478	internal::PropertyMatcher<Class, PropertyType,
4479	PropertyType (Class::*)() const&>(
4480	property, MatcherCast<const PropertyType&>(matcher)));
4481	}
4482
4483	// Three-argument form for reference-qualified member functions.
4484	template <typename Class, typename PropertyType, typename PropertyMatcher>
4485	inline PolymorphicMatcher<internal::PropertyMatcher<
4486	Class, PropertyType, PropertyType (Class::*)() const&>>
4487	Property(const std::string& property_name,
4488	PropertyType (Class::*property)() const&,
4489	const PropertyMatcher& matcher) {
4490	return MakePolymorphicMatcher(
4491	internal::PropertyMatcher<Class, PropertyType,
4492	PropertyType (Class::*)() const&>(
4493	property_name, property, MatcherCast<const PropertyType&>(matcher)));
4494	}
4495
4496	// Creates a matcher that matches an object if and only if the result of
4497	// applying a callable to x matches 'matcher'. For example,
4498	// ResultOf(f, StartsWith("hi"))
4499	// matches a Foo object x if and only if f(x) starts with "hi".
4500	// `callable` parameter can be a function, function pointer, or a functor. It is
4501	// required to keep no state affecting the results of the calls on it and make
4502	// no assumptions about how many calls will be made. Any state it keeps must be
4503	// protected from the concurrent access.
4504	template <typename Callable, typename InnerMatcher>
4505	internal::ResultOfMatcher<Callable, InnerMatcher> ResultOf(
4506	Callable callable, InnerMatcher matcher) {
4507	return internal::ResultOfMatcher<Callable, InnerMatcher>(std::move(callable),
4508	std::move(matcher));
4509	}
4510
4511	// Same as ResultOf() above, but also takes a description of the `callable`
4512	// result to provide better error messages.
4513	template <typename Callable, typename InnerMatcher>
4514	internal::ResultOfMatcher<Callable, InnerMatcher> ResultOf(
4515	const std::string& result_description, Callable callable,
4516	InnerMatcher matcher) {
4517	return internal::ResultOfMatcher<Callable, InnerMatcher>(
4518	result_description, std::move(callable), std::move(matcher));
4519	}
4520
4521	// String matchers.
4522
4523	// Matches a string equal to str.
4524	template <typename T = std::string>
4525	PolymorphicMatcher<internal::StrEqualityMatcher<std::string>> StrEq(
4526	const internal::StringLike<T>& str) {
4527	return MakePolymorphicMatcher(
4528	impl: internal::StrEqualityMatcher<std::string>(std::string(str), true, true));
4529	}
4530
4531	// Matches a string not equal to str.
4532	template <typename T = std::string>
4533	PolymorphicMatcher<internal::StrEqualityMatcher<std::string>> StrNe(
4534	const internal::StringLike<T>& str) {
4535	return MakePolymorphicMatcher(
4536	impl: internal::StrEqualityMatcher<std::string>(std::string(str), false, true));
4537	}
4538
4539	// Matches a string equal to str, ignoring case.
4540	template <typename T = std::string>
4541	PolymorphicMatcher<internal::StrEqualityMatcher<std::string>> StrCaseEq(
4542	const internal::StringLike<T>& str) {
4543	return MakePolymorphicMatcher(
4544	impl: internal::StrEqualityMatcher<std::string>(std::string(str), true, false));
4545	}
4546
4547	// Matches a string not equal to str, ignoring case.
4548	template <typename T = std::string>
4549	PolymorphicMatcher<internal::StrEqualityMatcher<std::string>> StrCaseNe(
4550	const internal::StringLike<T>& str) {
4551	return MakePolymorphicMatcher(impl: internal::StrEqualityMatcher<std::string>(
4552	std::string(str), false, false));
4553	}
4554
4555	// Creates a matcher that matches any string, std::string, or C string
4556	// that contains the given substring.
4557	template <typename T = std::string>
4558	PolymorphicMatcher<internal::HasSubstrMatcher<std::string>> HasSubstr(
4559	const internal::StringLike<T>& substring) {
4560	return MakePolymorphicMatcher(
4561	impl: internal::HasSubstrMatcher<std::string>(std::string(substring)));
4562	}
4563
4564	// Matches a string that starts with 'prefix' (case-sensitive).
4565	template <typename T = std::string>
4566	PolymorphicMatcher<internal::StartsWithMatcher<std::string>> StartsWith(
4567	const internal::StringLike<T>& prefix) {
4568	return MakePolymorphicMatcher(
4569	impl: internal::StartsWithMatcher<std::string>(std::string(prefix)));
4570	}
4571
4572	// Matches a string that ends with 'suffix' (case-sensitive).
4573	template <typename T = std::string>
4574	PolymorphicMatcher<internal::EndsWithMatcher<std::string>> EndsWith(
4575	const internal::StringLike<T>& suffix) {
4576	return MakePolymorphicMatcher(
4577	impl: internal::EndsWithMatcher<std::string>(std::string(suffix)));
4578	}
4579
4580	#if GTEST_HAS_STD_WSTRING
4581	// Wide string matchers.
4582
4583	// Matches a string equal to str.
4584	inline PolymorphicMatcher<internal::StrEqualityMatcher<std::wstring>> StrEq(
4585	const std::wstring& str) {
4586	return MakePolymorphicMatcher(
4587	impl: internal::StrEqualityMatcher<std::wstring>(str, true, true));
4588	}
4589
4590	// Matches a string not equal to str.
4591	inline PolymorphicMatcher<internal::StrEqualityMatcher<std::wstring>> StrNe(
4592	const std::wstring& str) {
4593	return MakePolymorphicMatcher(
4594	impl: internal::StrEqualityMatcher<std::wstring>(str, false, true));
4595	}
4596
4597	// Matches a string equal to str, ignoring case.
4598	inline PolymorphicMatcher<internal::StrEqualityMatcher<std::wstring>> StrCaseEq(
4599	const std::wstring& str) {
4600	return MakePolymorphicMatcher(
4601	impl: internal::StrEqualityMatcher<std::wstring>(str, true, false));
4602	}
4603
4604	// Matches a string not equal to str, ignoring case.
4605	inline PolymorphicMatcher<internal::StrEqualityMatcher<std::wstring>> StrCaseNe(
4606	const std::wstring& str) {
4607	return MakePolymorphicMatcher(
4608	impl: internal::StrEqualityMatcher<std::wstring>(str, false, false));
4609	}
4610
4611	// Creates a matcher that matches any ::wstring, std::wstring, or C wide string
4612	// that contains the given substring.
4613	inline PolymorphicMatcher<internal::HasSubstrMatcher<std::wstring>> HasSubstr(
4614	const std::wstring& substring) {
4615	return MakePolymorphicMatcher(
4616	impl: internal::HasSubstrMatcher<std::wstring>(substring));
4617	}
4618
4619	// Matches a string that starts with 'prefix' (case-sensitive).
4620	inline PolymorphicMatcher<internal::StartsWithMatcher<std::wstring>> StartsWith(
4621	const std::wstring& prefix) {
4622	return MakePolymorphicMatcher(
4623	impl: internal::StartsWithMatcher<std::wstring>(prefix));
4624	}
4625
4626	// Matches a string that ends with 'suffix' (case-sensitive).
4627	inline PolymorphicMatcher<internal::EndsWithMatcher<std::wstring>> EndsWith(
4628	const std::wstring& suffix) {
4629	return MakePolymorphicMatcher(
4630	impl: internal::EndsWithMatcher<std::wstring>(suffix));
4631	}
4632
4633	#endif // GTEST_HAS_STD_WSTRING
4634
4635	// Creates a polymorphic matcher that matches a 2-tuple where the
4636	// first field == the second field.
4637	inline internal::Eq2Matcher Eq() { return internal::Eq2Matcher(); }
4638
4639	// Creates a polymorphic matcher that matches a 2-tuple where the
4640	// first field >= the second field.
4641	inline internal::Ge2Matcher Ge() { return internal::Ge2Matcher(); }
4642
4643	// Creates a polymorphic matcher that matches a 2-tuple where the
4644	// first field > the second field.
4645	inline internal::Gt2Matcher Gt() { return internal::Gt2Matcher(); }
4646
4647	// Creates a polymorphic matcher that matches a 2-tuple where the
4648	// first field <= the second field.
4649	inline internal::Le2Matcher Le() { return internal::Le2Matcher(); }
4650
4651	// Creates a polymorphic matcher that matches a 2-tuple where the
4652	// first field < the second field.
4653	inline internal::Lt2Matcher Lt() { return internal::Lt2Matcher(); }
4654
4655	// Creates a polymorphic matcher that matches a 2-tuple where the
4656	// first field != the second field.
4657	inline internal::Ne2Matcher Ne() { return internal::Ne2Matcher(); }
4658
4659	// Creates a polymorphic matcher that matches a 2-tuple where
4660	// FloatEq(first field) matches the second field.
4661	inline internal::FloatingEq2Matcher<float> FloatEq() {
4662	return internal::FloatingEq2Matcher<float>();
4663	}
4664
4665	// Creates a polymorphic matcher that matches a 2-tuple where
4666	// DoubleEq(first field) matches the second field.
4667	inline internal::FloatingEq2Matcher<double> DoubleEq() {
4668	return internal::FloatingEq2Matcher<double>();
4669	}
4670
4671	// Creates a polymorphic matcher that matches a 2-tuple where
4672	// FloatEq(first field) matches the second field with NaN equality.
4673	inline internal::FloatingEq2Matcher<float> NanSensitiveFloatEq() {
4674	return internal::FloatingEq2Matcher<float>(true);
4675	}
4676
4677	// Creates a polymorphic matcher that matches a 2-tuple where
4678	// DoubleEq(first field) matches the second field with NaN equality.
4679	inline internal::FloatingEq2Matcher<double> NanSensitiveDoubleEq() {
4680	return internal::FloatingEq2Matcher<double>(true);
4681	}
4682
4683	// Creates a polymorphic matcher that matches a 2-tuple where
4684	// FloatNear(first field, max_abs_error) matches the second field.
4685	inline internal::FloatingEq2Matcher<float> FloatNear(float max_abs_error) {
4686	return internal::FloatingEq2Matcher<float>(max_abs_error);
4687	}
4688
4689	// Creates a polymorphic matcher that matches a 2-tuple where
4690	// DoubleNear(first field, max_abs_error) matches the second field.
4691	inline internal::FloatingEq2Matcher<double> DoubleNear(double max_abs_error) {
4692	return internal::FloatingEq2Matcher<double>(max_abs_error);
4693	}
4694
4695	// Creates a polymorphic matcher that matches a 2-tuple where
4696	// FloatNear(first field, max_abs_error) matches the second field with NaN
4697	// equality.
4698	inline internal::FloatingEq2Matcher<float> NanSensitiveFloatNear(
4699	float max_abs_error) {
4700	return internal::FloatingEq2Matcher<float>(max_abs_error, true);
4701	}
4702
4703	// Creates a polymorphic matcher that matches a 2-tuple where
4704	// DoubleNear(first field, max_abs_error) matches the second field with NaN
4705	// equality.
4706	inline internal::FloatingEq2Matcher<double> NanSensitiveDoubleNear(
4707	double max_abs_error) {
4708	return internal::FloatingEq2Matcher<double>(max_abs_error, true);
4709	}
4710
4711	// Creates a matcher that matches any value of type T that m doesn't
4712	// match.
4713	template <typename InnerMatcher>
4714	inline internal::NotMatcher<InnerMatcher> Not(InnerMatcher m) {
4715	return internal::NotMatcher<InnerMatcher>(m);
4716	}
4717
4718	// Returns a matcher that matches anything that satisfies the given
4719	// predicate. The predicate can be any unary function or functor
4720	// whose return type can be implicitly converted to bool.
4721	template <typename Predicate>
4722	inline PolymorphicMatcher<internal::TrulyMatcher<Predicate>> Truly(
4723	Predicate pred) {
4724	return MakePolymorphicMatcher(internal::TrulyMatcher<Predicate>(pred));
4725	}
4726
4727	// Returns a matcher that matches the container size. The container must
4728	// support both size() and size_type which all STL-like containers provide.
4729	// Note that the parameter 'size' can be a value of type size_type as well as
4730	// matcher. For instance:
4731	// EXPECT_THAT(container, SizeIs(2)); // Checks container has 2 elements.
4732	// EXPECT_THAT(container, SizeIs(Le(2)); // Checks container has at most 2.
4733	template <typename SizeMatcher>
4734	inline internal::SizeIsMatcher<SizeMatcher> SizeIs(
4735	const SizeMatcher& size_matcher) {
4736	return internal::SizeIsMatcher<SizeMatcher>(size_matcher);
4737	}
4738
4739	// Returns a matcher that matches the distance between the container's begin()
4740	// iterator and its end() iterator, i.e. the size of the container. This matcher
4741	// can be used instead of SizeIs with containers such as std::forward_list which
4742	// do not implement size(). The container must provide const_iterator (with
4743	// valid iterator_traits), begin() and end().
4744	template <typename DistanceMatcher>
4745	inline internal::BeginEndDistanceIsMatcher<DistanceMatcher> BeginEndDistanceIs(
4746	const DistanceMatcher& distance_matcher) {
4747	return internal::BeginEndDistanceIsMatcher<DistanceMatcher>(distance_matcher);
4748	}
4749
4750	// Returns a matcher that matches an equal container.
4751	// This matcher behaves like Eq(), but in the event of mismatch lists the
4752	// values that are included in one container but not the other. (Duplicate
4753	// values and order differences are not explained.)
4754	template <typename Container>
4755	inline PolymorphicMatcher<
4756	internal::ContainerEqMatcher<typename std::remove_const<Container>::type>>
4757	ContainerEq(const Container& rhs) {
4758	return MakePolymorphicMatcher(internal::ContainerEqMatcher<Container>(rhs));
4759	}
4760
4761	// Returns a matcher that matches a container that, when sorted using
4762	// the given comparator, matches container_matcher.
4763	template <typename Comparator, typename ContainerMatcher>
4764	inline internal::WhenSortedByMatcher<Comparator, ContainerMatcher> WhenSortedBy(
4765	const Comparator& comparator, const ContainerMatcher& container_matcher) {
4766	return internal::WhenSortedByMatcher<Comparator, ContainerMatcher>(
4767	comparator, container_matcher);
4768	}
4769
4770	// Returns a matcher that matches a container that, when sorted using
4771	// the < operator, matches container_matcher.
4772	template <typename ContainerMatcher>
4773	inline internal::WhenSortedByMatcher<internal::LessComparator, ContainerMatcher>
4774	WhenSorted(const ContainerMatcher& container_matcher) {
4775	return internal::WhenSortedByMatcher<internal::LessComparator,
4776	ContainerMatcher>(
4777	internal::LessComparator(), container_matcher);
4778	}
4779
4780	// Matches an STL-style container or a native array that contains the
4781	// same number of elements as in rhs, where its i-th element and rhs's
4782	// i-th element (as a pair) satisfy the given pair matcher, for all i.
4783	// TupleMatcher must be able to be safely cast to Matcher<std::tuple<const
4784	// T1&, const T2&> >, where T1 and T2 are the types of elements in the
4785	// LHS container and the RHS container respectively.
4786	template <typename TupleMatcher, typename Container>
4787	inline internal::PointwiseMatcher<TupleMatcher,
4788	typename std::remove_const<Container>::type>
4789	Pointwise(const TupleMatcher& tuple_matcher, const Container& rhs) {
4790	return internal::PointwiseMatcher<TupleMatcher, Container>(tuple_matcher,
4791	rhs);
4792	}
4793
4794	// Supports the Pointwise(m, {a, b, c}) syntax.
4795	template <typename TupleMatcher, typename T>
4796	inline internal::PointwiseMatcher<TupleMatcher, std::vector<T>> Pointwise(
4797	const TupleMatcher& tuple_matcher, std::initializer_list<T> rhs) {
4798	return Pointwise(tuple_matcher, std::vector<T>(rhs));
4799	}
4800
4801	// UnorderedPointwise(pair_matcher, rhs) matches an STL-style
4802	// container or a native array that contains the same number of
4803	// elements as in rhs, where in some permutation of the container, its
4804	// i-th element and rhs's i-th element (as a pair) satisfy the given
4805	// pair matcher, for all i. Tuple2Matcher must be able to be safely
4806	// cast to Matcher<std::tuple<const T1&, const T2&> >, where T1 and T2 are
4807	// the types of elements in the LHS container and the RHS container
4808	// respectively.
4809	//
4810	// This is like Pointwise(pair_matcher, rhs), except that the element
4811	// order doesn't matter.
4812	template <typename Tuple2Matcher, typename RhsContainer>
4813	inline internal::UnorderedElementsAreArrayMatcher<
4814	typename internal::BoundSecondMatcher<
4815	Tuple2Matcher,
4816	typename internal::StlContainerView<
4817	typename std::remove_const<RhsContainer>::type>::type::value_type>>
4818	UnorderedPointwise(const Tuple2Matcher& tuple2_matcher,
4819	const RhsContainer& rhs_container) {
4820	// RhsView allows the same code to handle RhsContainer being a
4821	// STL-style container and it being a native C-style array.
4822	typedef typename internal::StlContainerView<RhsContainer> RhsView;
4823	typedef typename RhsView::type RhsStlContainer;
4824	typedef typename RhsStlContainer::value_type Second;
4825	const RhsStlContainer& rhs_stl_container =
4826	RhsView::ConstReference(rhs_container);
4827
4828	// Create a matcher for each element in rhs_container.
4829	::std::vector<internal::BoundSecondMatcher<Tuple2Matcher, Second>> matchers;
4830	for (auto it = rhs_stl_container.begin(); it != rhs_stl_container.end();
4831	++it) {
4832	matchers.push_back(internal::MatcherBindSecond(tuple2_matcher, *it));
4833	}
4834
4835	// Delegate the work to UnorderedElementsAreArray().
4836	return UnorderedElementsAreArray(matchers);
4837	}
4838
4839	// Supports the UnorderedPointwise(m, {a, b, c}) syntax.
4840	template <typename Tuple2Matcher, typename T>
4841	inline internal::UnorderedElementsAreArrayMatcher<
4842	typename internal::BoundSecondMatcher<Tuple2Matcher, T>>
4843	UnorderedPointwise(const Tuple2Matcher& tuple2_matcher,
4844	std::initializer_list<T> rhs) {
4845	return UnorderedPointwise(tuple2_matcher, std::vector<T>(rhs));
4846	}
4847
4848	// Matches an STL-style container or a native array that contains at
4849	// least one element matching the given value or matcher.
4850	//
4851	// Examples:
4852	// ::std::set<int> page_ids;
4853	// page_ids.insert(3);
4854	// page_ids.insert(1);
4855	// EXPECT_THAT(page_ids, Contains(1));
4856	// EXPECT_THAT(page_ids, Contains(Gt(2)));
4857	// EXPECT_THAT(page_ids, Not(Contains(4))); // See below for Times(0)
4858	//
4859	// ::std::map<int, size_t> page_lengths;
4860	// page_lengths[1] = 100;
4861	// EXPECT_THAT(page_lengths,
4862	// Contains(::std::pair<const int, size_t>(1, 100)));
4863	//
4864	// const char* user_ids[] = { "joe", "mike", "tom" };
4865	// EXPECT_THAT(user_ids, Contains(Eq(::std::string("tom"))));
4866	//
4867	// The matcher supports a modifier `Times` that allows to check for arbitrary
4868	// occurrences including testing for absence with Times(0).
4869	//
4870	// Examples:
4871	// ::std::vector<int> ids;
4872	// ids.insert(1);
4873	// ids.insert(1);
4874	// ids.insert(3);
4875	// EXPECT_THAT(ids, Contains(1).Times(2)); // 1 occurs 2 times
4876	// EXPECT_THAT(ids, Contains(2).Times(0)); // 2 is not present
4877	// EXPECT_THAT(ids, Contains(3).Times(Ge(1))); // 3 occurs at least once
4878
4879	template <typename M>
4880	inline internal::ContainsMatcher<M> Contains(M matcher) {
4881	return internal::ContainsMatcher<M>(matcher);
4882	}
4883
4884	// IsSupersetOf(iterator_first, iterator_last)
4885	// IsSupersetOf(pointer, count)
4886	// IsSupersetOf(array)
4887	// IsSupersetOf(container)
4888	// IsSupersetOf({e1, e2, ..., en})
4889	//
4890	// IsSupersetOf() verifies that a surjective partial mapping onto a collection
4891	// of matchers exists. In other words, a container matches
4892	// IsSupersetOf({e1, ..., en}) if and only if there is a permutation
4893	// {y1, ..., yn} of some of the container's elements where y1 matches e1,
4894	// ..., and yn matches en. Obviously, the size of the container must be >= n
4895	// in order to have a match. Examples:
4896	//
4897	// - {1, 2, 3} matches IsSupersetOf({Ge(3), Ne(0)}), as 3 matches Ge(3) and
4898	// 1 matches Ne(0).
4899	// - {1, 2} doesn't match IsSupersetOf({Eq(1), Lt(2)}), even though 1 matches
4900	// both Eq(1) and Lt(2). The reason is that different matchers must be used
4901	// for elements in different slots of the container.
4902	// - {1, 1, 2} matches IsSupersetOf({Eq(1), Lt(2)}), as (the first) 1 matches
4903	// Eq(1) and (the second) 1 matches Lt(2).
4904	// - {1, 2, 3} matches IsSupersetOf(Gt(1), Gt(1)), as 2 matches (the first)
4905	// Gt(1) and 3 matches (the second) Gt(1).
4906	//
4907	// The matchers can be specified as an array, a pointer and count, a container,
4908	// an initializer list, or an STL iterator range. In each of these cases, the
4909	// underlying matchers can be either values or matchers.
4910
4911	template <typename Iter>
4912	inline internal::UnorderedElementsAreArrayMatcher<
4913	typename ::std::iterator_traits<Iter>::value_type>
4914	IsSupersetOf(Iter first, Iter last) {
4915	typedef typename ::std::iterator_traits<Iter>::value_type T;
4916	return internal::UnorderedElementsAreArrayMatcher<T>(
4917	internal::UnorderedMatcherRequire::Superset, first, last);
4918	}
4919
4920	template <typename T>
4921	inline internal::UnorderedElementsAreArrayMatcher<T> IsSupersetOf(
4922	const T* pointer, size_t count) {
4923	return IsSupersetOf(pointer, pointer + count);
4924	}
4925
4926	template <typename T, size_t N>
4927	inline internal::UnorderedElementsAreArrayMatcher<T> IsSupersetOf(
4928	const T (&array)[N]) {
4929	return IsSupersetOf(array, N);
4930	}
4931
4932	template <typename Container>
4933	inline internal::UnorderedElementsAreArrayMatcher<
4934	typename Container::value_type>
4935	IsSupersetOf(const Container& container) {
4936	return IsSupersetOf(container.begin(), container.end());
4937	}
4938
4939	template <typename T>
4940	inline internal::UnorderedElementsAreArrayMatcher<T> IsSupersetOf(
4941	::std::initializer_list<T> xs) {
4942	return IsSupersetOf(xs.begin(), xs.end());
4943	}
4944
4945	// IsSubsetOf(iterator_first, iterator_last)
4946	// IsSubsetOf(pointer, count)
4947	// IsSubsetOf(array)
4948	// IsSubsetOf(container)
4949	// IsSubsetOf({e1, e2, ..., en})
4950	//
4951	// IsSubsetOf() verifies that an injective mapping onto a collection of matchers
4952	// exists. In other words, a container matches IsSubsetOf({e1, ..., en}) if and
4953	// only if there is a subset of matchers {m1, ..., mk} which would match the
4954	// container using UnorderedElementsAre. Obviously, the size of the container
4955	// must be <= n in order to have a match. Examples:
4956	//
4957	// - {1} matches IsSubsetOf({Gt(0), Lt(0)}), as 1 matches Gt(0).
4958	// - {1, -1} matches IsSubsetOf({Lt(0), Gt(0)}), as 1 matches Gt(0) and -1
4959	// matches Lt(0).
4960	// - {1, 2} doesn't matches IsSubsetOf({Gt(0), Lt(0)}), even though 1 and 2 both
4961	// match Gt(0). The reason is that different matchers must be used for
4962	// elements in different slots of the container.
4963	//
4964	// The matchers can be specified as an array, a pointer and count, a container,
4965	// an initializer list, or an STL iterator range. In each of these cases, the
4966	// underlying matchers can be either values or matchers.
4967
4968	template <typename Iter>
4969	inline internal::UnorderedElementsAreArrayMatcher<
4970	typename ::std::iterator_traits<Iter>::value_type>
4971	IsSubsetOf(Iter first, Iter last) {
4972	typedef typename ::std::iterator_traits<Iter>::value_type T;
4973	return internal::UnorderedElementsAreArrayMatcher<T>(
4974	internal::UnorderedMatcherRequire::Subset, first, last);
4975	}
4976
4977	template <typename T>
4978	inline internal::UnorderedElementsAreArrayMatcher<T> IsSubsetOf(
4979	const T* pointer, size_t count) {
4980	return IsSubsetOf(pointer, pointer + count);
4981	}
4982
4983	template <typename T, size_t N>
4984	inline internal::UnorderedElementsAreArrayMatcher<T> IsSubsetOf(
4985	const T (&array)[N]) {
4986	return IsSubsetOf(array, N);
4987	}
4988
4989	template <typename Container>
4990	inline internal::UnorderedElementsAreArrayMatcher<
4991	typename Container::value_type>
4992	IsSubsetOf(const Container& container) {
4993	return IsSubsetOf(container.begin(), container.end());
4994	}
4995
4996	template <typename T>
4997	inline internal::UnorderedElementsAreArrayMatcher<T> IsSubsetOf(
4998	::std::initializer_list<T> xs) {
4999	return IsSubsetOf(xs.begin(), xs.end());
5000	}
5001
5002	// Matches an STL-style container or a native array that contains only
5003	// elements matching the given value or matcher.
5004	//
5005	// Each(m) is semantically equivalent to `Not(Contains(Not(m)))`. Only
5006	// the messages are different.
5007	//
5008	// Examples:
5009	// ::std::set<int> page_ids;
5010	// // Each(m) matches an empty container, regardless of what m is.
5011	// EXPECT_THAT(page_ids, Each(Eq(1)));
5012	// EXPECT_THAT(page_ids, Each(Eq(77)));
5013	//
5014	// page_ids.insert(3);
5015	// EXPECT_THAT(page_ids, Each(Gt(0)));
5016	// EXPECT_THAT(page_ids, Not(Each(Gt(4))));
5017	// page_ids.insert(1);
5018	// EXPECT_THAT(page_ids, Not(Each(Lt(2))));
5019	//
5020	// ::std::map<int, size_t> page_lengths;
5021	// page_lengths[1] = 100;
5022	// page_lengths[2] = 200;
5023	// page_lengths[3] = 300;
5024	// EXPECT_THAT(page_lengths, Not(Each(Pair(1, 100))));
5025	// EXPECT_THAT(page_lengths, Each(Key(Le(3))));
5026	//
5027	// const char* user_ids[] = { "joe", "mike", "tom" };
5028	// EXPECT_THAT(user_ids, Not(Each(Eq(::std::string("tom")))));
5029	template <typename M>
5030	inline internal::EachMatcher<M> Each(M matcher) {
5031	return internal::EachMatcher<M>(matcher);
5032	}
5033
5034	// Key(inner_matcher) matches an std::pair whose 'first' field matches
5035	// inner_matcher. For example, Contains(Key(Ge(5))) can be used to match an
5036	// std::map that contains at least one element whose key is >= 5.
5037	template <typename M>
5038	inline internal::KeyMatcher<M> Key(M inner_matcher) {
5039	return internal::KeyMatcher<M>(inner_matcher);
5040	}
5041
5042	// Pair(first_matcher, second_matcher) matches a std::pair whose 'first' field
5043	// matches first_matcher and whose 'second' field matches second_matcher. For
5044	// example, EXPECT_THAT(map_type, ElementsAre(Pair(Ge(5), "foo"))) can be used
5045	// to match a std::map<int, string> that contains exactly one element whose key
5046	// is >= 5 and whose value equals "foo".
5047	template <typename FirstMatcher, typename SecondMatcher>
5048	inline internal::PairMatcher<FirstMatcher, SecondMatcher> Pair(
5049	FirstMatcher first_matcher, SecondMatcher second_matcher) {
5050	return internal::PairMatcher<FirstMatcher, SecondMatcher>(first_matcher,
5051	second_matcher);
5052	}
5053
5054	namespace no_adl {
5055	// Conditional() creates a matcher that conditionally uses either the first or
5056	// second matcher provided. For example, we could create an `equal if, and only
5057	// if' matcher using the Conditional wrapper as follows:
5058	//
5059	// EXPECT_THAT(result, Conditional(condition, Eq(expected), Ne(expected)));
5060	template <typename MatcherTrue, typename MatcherFalse>
5061	internal::ConditionalMatcher<MatcherTrue, MatcherFalse> Conditional(
5062	bool condition, MatcherTrue matcher_true, MatcherFalse matcher_false) {
5063	return internal::ConditionalMatcher<MatcherTrue, MatcherFalse>(
5064	condition, std::move(matcher_true), std::move(matcher_false));
5065	}
5066
5067	// FieldsAre(matchers...) matches piecewise the fields of compatible structs.
5068	// These include those that support `get<I>(obj)`, and when structured bindings
5069	// are enabled any class that supports them.
5070	// In particular, `std::tuple`, `std::pair`, `std::array` and aggregate types.
5071	template <typename... M>
5072	internal::FieldsAreMatcher<typename std::decay<M>::type...> FieldsAre(
5073	M&&... matchers) {
5074	return internal::FieldsAreMatcher<typename std::decay<M>::type...>(
5075	std::forward<M>(matchers)...);
5076	}
5077
5078	// Creates a matcher that matches a pointer (raw or smart) that matches
5079	// inner_matcher.
5080	template <typename InnerMatcher>
5081	inline internal::PointerMatcher<InnerMatcher> Pointer(
5082	const InnerMatcher& inner_matcher) {
5083	return internal::PointerMatcher<InnerMatcher>(inner_matcher);
5084	}
5085
5086	// Creates a matcher that matches an object that has an address that matches
5087	// inner_matcher.
5088	template <typename InnerMatcher>
5089	inline internal::AddressMatcher<InnerMatcher> Address(
5090	const InnerMatcher& inner_matcher) {
5091	return internal::AddressMatcher<InnerMatcher>(inner_matcher);
5092	}
5093
5094	// Matches a base64 escaped string, when the unescaped string matches the
5095	// internal matcher.
5096	template <typename MatcherType>
5097	internal::WhenBase64UnescapedMatcher WhenBase64Unescaped(
5098	const MatcherType& internal_matcher) {
5099	return internal::WhenBase64UnescapedMatcher(internal_matcher);
5100	}
5101	} // namespace no_adl
5102
5103	// Returns a predicate that is satisfied by anything that matches the
5104	// given matcher.
5105	template <typename M>
5106	inline internal::MatcherAsPredicate<M> Matches(M matcher) {
5107	return internal::MatcherAsPredicate<M>(matcher);
5108	}
5109
5110	// Returns true if and only if the value matches the matcher.
5111	template <typename T, typename M>
5112	inline bool Value(const T& value, M matcher) {
5113	return testing::Matches(matcher)(value);
5114	}
5115
5116	// Matches the value against the given matcher and explains the match
5117	// result to listener.
5118	template <typename T, typename M>
5119	inline bool ExplainMatchResult(M matcher, const T& value,
5120	MatchResultListener* listener) {
5121	return SafeMatcherCast<const T&>(matcher).MatchAndExplain(value, listener);
5122	}
5123
5124	// Returns a string representation of the given matcher. Useful for description
5125	// strings of matchers defined using MATCHER_P* macros that accept matchers as
5126	// their arguments. For example:
5127	//
5128	// MATCHER_P(XAndYThat, matcher,
5129	// "X that " + DescribeMatcher<int>(matcher, negation) +
5130	// (negation ? " or" : " and") + " Y that " +
5131	// DescribeMatcher<double>(matcher, negation)) {
5132	// return ExplainMatchResult(matcher, arg.x(), result_listener) &&
5133	// ExplainMatchResult(matcher, arg.y(), result_listener);
5134	// }
5135	template <typename T, typename M>
5136	std::string DescribeMatcher(const M& matcher, bool negation = false) {
5137	::std::stringstream ss;
5138	Matcher<T> monomorphic_matcher = SafeMatcherCast<T>(matcher);
5139	if (negation) {
5140	monomorphic_matcher.DescribeNegationTo(&ss);
5141	} else {
5142	monomorphic_matcher.DescribeTo(&ss);
5143	}
5144	return ss.str();
5145	}
5146
5147	template <typename... Args>
5148	internal::ElementsAreMatcher<
5149	std::tuple<typename std::decay<const Args&>::type...>>
5150	ElementsAre(const Args&... matchers) {
5151	return internal::ElementsAreMatcher<
5152	std::tuple<typename std::decay<const Args&>::type...>>(
5153	std::make_tuple(matchers...));
5154	}
5155
5156	template <typename... Args>
5157	internal::UnorderedElementsAreMatcher<
5158	std::tuple<typename std::decay<const Args&>::type...>>
5159	UnorderedElementsAre(const Args&... matchers) {
5160	return internal::UnorderedElementsAreMatcher<
5161	std::tuple<typename std::decay<const Args&>::type...>>(
5162	std::make_tuple(matchers...));
5163	}
5164
5165	// Define variadic matcher versions.
5166	template <typename... Args>
5167	internal::AllOfMatcher<typename std::decay<const Args&>::type...> AllOf(
5168	const Args&... matchers) {
5169	return internal::AllOfMatcher<typename std::decay<const Args&>::type...>(
5170	matchers...);
5171	}
5172
5173	template <typename... Args>
5174	internal::AnyOfMatcher<typename std::decay<const Args&>::type...> AnyOf(
5175	const Args&... matchers) {
5176	return internal::AnyOfMatcher<typename std::decay<const Args&>::type...>(
5177	matchers...);
5178	}
5179
5180	// AnyOfArray(array)
5181	// AnyOfArray(pointer, count)
5182	// AnyOfArray(container)
5183	// AnyOfArray({ e1, e2, ..., en })
5184	// AnyOfArray(iterator_first, iterator_last)
5185	//
5186	// AnyOfArray() verifies whether a given value matches any member of a
5187	// collection of matchers.
5188	//
5189	// AllOfArray(array)
5190	// AllOfArray(pointer, count)
5191	// AllOfArray(container)
5192	// AllOfArray({ e1, e2, ..., en })
5193	// AllOfArray(iterator_first, iterator_last)
5194	//
5195	// AllOfArray() verifies whether a given value matches all members of a
5196	// collection of matchers.
5197	//
5198	// The matchers can be specified as an array, a pointer and count, a container,
5199	// an initializer list, or an STL iterator range. In each of these cases, the
5200	// underlying matchers can be either values or matchers.
5201
5202	template <typename Iter>
5203	inline internal::AnyOfArrayMatcher<
5204	typename ::std::iterator_traits<Iter>::value_type>
5205	AnyOfArray(Iter first, Iter last) {
5206	return internal::AnyOfArrayMatcher<
5207	typename ::std::iterator_traits<Iter>::value_type>(first, last);
5208	}
5209
5210	template <typename Iter>
5211	inline internal::AllOfArrayMatcher<
5212	typename ::std::iterator_traits<Iter>::value_type>
5213	AllOfArray(Iter first, Iter last) {
5214	return internal::AllOfArrayMatcher<
5215	typename ::std::iterator_traits<Iter>::value_type>(first, last);
5216	}
5217
5218	template <typename T>
5219	inline internal::AnyOfArrayMatcher<T> AnyOfArray(const T* ptr, size_t count) {
5220	return AnyOfArray(ptr, ptr + count);
5221	}
5222
5223	template <typename T>
5224	inline internal::AllOfArrayMatcher<T> AllOfArray(const T* ptr, size_t count) {
5225	return AllOfArray(ptr, ptr + count);
5226	}
5227
5228	template <typename T, size_t N>
5229	inline internal::AnyOfArrayMatcher<T> AnyOfArray(const T (&array)[N]) {
5230	return AnyOfArray(array, N);
5231	}
5232
5233	template <typename T, size_t N>
5234	inline internal::AllOfArrayMatcher<T> AllOfArray(const T (&array)[N]) {
5235	return AllOfArray(array, N);
5236	}
5237
5238	template <typename Container>
5239	inline internal::AnyOfArrayMatcher<typename Container::value_type> AnyOfArray(
5240	const Container& container) {
5241	return AnyOfArray(container.begin(), container.end());
5242	}
5243
5244	template <typename Container>
5245	inline internal::AllOfArrayMatcher<typename Container::value_type> AllOfArray(
5246	const Container& container) {
5247	return AllOfArray(container.begin(), container.end());
5248	}
5249
5250	template <typename T>
5251	inline internal::AnyOfArrayMatcher<T> AnyOfArray(
5252	::std::initializer_list<T> xs) {
5253	return AnyOfArray(xs.begin(), xs.end());
5254	}
5255
5256	template <typename T>
5257	inline internal::AllOfArrayMatcher<T> AllOfArray(
5258	::std::initializer_list<T> xs) {
5259	return AllOfArray(xs.begin(), xs.end());
5260	}
5261
5262	// Args<N1, N2, ..., Nk>(a_matcher) matches a tuple if the selected
5263	// fields of it matches a_matcher. C++ doesn't support default
5264	// arguments for function templates, so we have to overload it.
5265	template <size_t... k, typename InnerMatcher>
5266	internal::ArgsMatcher<typename std::decay<InnerMatcher>::type, k...> Args(
5267	InnerMatcher&& matcher) {
5268	return internal::ArgsMatcher<typename std::decay<InnerMatcher>::type, k...>(
5269	std::forward<InnerMatcher>(matcher));
5270	}
5271
5272	// AllArgs(m) is a synonym of m. This is useful in
5273	//
5274	// EXPECT_CALL(foo, Bar(_, _)).With(AllArgs(Eq()));
5275	//
5276	// which is easier to read than
5277	//
5278	// EXPECT_CALL(foo, Bar(_, _)).With(Eq());
5279	template <typename InnerMatcher>
5280	inline InnerMatcher AllArgs(const InnerMatcher& matcher) {
5281	return matcher;
5282	}
5283
5284	// Returns a matcher that matches the value of an optional<> type variable.
5285	// The matcher implementation only uses '!arg' and requires that the optional<>
5286	// type has a 'value_type' member type and that '*arg' is of type 'value_type'
5287	// and is printable using 'PrintToString'. It is compatible with
5288	// std::optional/std::experimental::optional.
5289	// Note that to compare an optional type variable against nullopt you should
5290	// use Eq(nullopt) and not Eq(Optional(nullopt)). The latter implies that the
5291	// optional value contains an optional itself.
5292	template <typename ValueMatcher>
5293	inline internal::OptionalMatcher<ValueMatcher> Optional(
5294	const ValueMatcher& value_matcher) {
5295	return internal::OptionalMatcher<ValueMatcher>(value_matcher);
5296	}
5297
5298	// Returns a matcher that matches the value of a absl::any type variable.
5299	template <typename T>
5300	PolymorphicMatcher<internal::any_cast_matcher::AnyCastMatcher<T>> AnyWith(
5301	const Matcher<const T&>& matcher) {
5302	return MakePolymorphicMatcher(
5303	internal::any_cast_matcher::AnyCastMatcher<T>(matcher));
5304	}
5305
5306	// Returns a matcher that matches the value of a variant<> type variable.
5307	// The matcher implementation uses ADL to find the holds_alternative and get
5308	// functions.
5309	// It is compatible with std::variant.
5310	template <typename T>
5311	PolymorphicMatcher<internal::variant_matcher::VariantMatcher<T>> VariantWith(
5312	const Matcher<const T&>& matcher) {
5313	return MakePolymorphicMatcher(
5314	internal::variant_matcher::VariantMatcher<T>(matcher));
5315	}
5316
5317	#if GTEST_HAS_EXCEPTIONS
5318
5319	// Anything inside the `internal` namespace is internal to the implementation
5320	// and must not be used in user code!
5321	namespace internal {
5322
5323	class WithWhatMatcherImpl {
5324	public:
5325	WithWhatMatcherImpl(Matcher<std::string> matcher)
5326	: matcher_(std::move(matcher)) {}
5327
5328	void DescribeTo(std::ostream* os) const {
5329	*os << "contains .what() that ";
5330	matcher_.DescribeTo(os);
5331	}
5332
5333	void DescribeNegationTo(std::ostream* os) const {
5334	*os << "contains .what() that does not ";
5335	matcher_.DescribeTo(os);
5336	}
5337
5338	template <typename Err>
5339	bool MatchAndExplain(const Err& err, MatchResultListener* listener) const {
5340	*listener << "which contains .what() (of value = " << err.what()
5341	<< ") that ";
5342	return matcher_.MatchAndExplain(err.what(), listener);
5343	}
5344
5345	private:
5346	const Matcher<std::string> matcher_;
5347	};
5348
5349	inline PolymorphicMatcher<WithWhatMatcherImpl> WithWhat(
5350	Matcher<std::string> m) {
5351	return MakePolymorphicMatcher(WithWhatMatcherImpl(std::move(m)));
5352	}
5353
5354	template <typename Err>
5355	class ExceptionMatcherImpl {
5356	class NeverThrown {
5357	public:
5358	const char* what() const noexcept {
5359	return "this exception should never be thrown";
5360	}
5361	};
5362
5363	// If the matchee raises an exception of a wrong type, we'd like to
5364	// catch it and print its message and type. To do that, we add an additional
5365	// catch clause:
5366	//
5367	// try { ... }
5368	// catch (const Err&) { /* an expected exception */ }
5369	// catch (const std::exception&) { /* exception of a wrong type */ }
5370	//
5371	// However, if the `Err` itself is `std::exception`, we'd end up with two
5372	// identical `catch` clauses:
5373	//
5374	// try { ... }
5375	// catch (const std::exception&) { /* an expected exception */ }
5376	// catch (const std::exception&) { /* exception of a wrong type */ }
5377	//
5378	// This can cause a warning or an error in some compilers. To resolve
5379	// the issue, we use a fake error type whenever `Err` is `std::exception`:
5380	//
5381	// try { ... }
5382	// catch (const std::exception&) { /* an expected exception */ }
5383	// catch (const NeverThrown&) { /* exception of a wrong type */ }
5384	using DefaultExceptionType = typename std::conditional<
5385	std::is_same<typename std::remove_cv<
5386	typename std::remove_reference<Err>::type>::type,
5387	std::exception>::value,
5388	const NeverThrown&, const std::exception&>::type;
5389
5390	public:
5391	ExceptionMatcherImpl(Matcher<const Err&> matcher)
5392	: matcher_(std::move(matcher)) {}
5393
5394	void DescribeTo(std::ostream* os) const {
5395	*os << "throws an exception which is a " << GetTypeName<Err>();
5396	*os << " which ";
5397	matcher_.DescribeTo(os);
5398	}
5399
5400	void DescribeNegationTo(std::ostream* os) const {
5401	*os << "throws an exception which is not a " << GetTypeName<Err>();
5402	*os << " which ";
5403	matcher_.DescribeNegationTo(os);
5404	}
5405
5406	template <typename T>
5407	bool MatchAndExplain(T&& x, MatchResultListener* listener) const {
5408	try {
5409	(void)(std::forward<T>(x)());
5410	} catch (const Err& err) {
5411	*listener << "throws an exception which is a " << GetTypeName<Err>();
5412	*listener << " ";
5413	return matcher_.MatchAndExplain(err, listener);
5414	} catch (DefaultExceptionType err) {
5415	#if GTEST_HAS_RTTI
5416	*listener << "throws an exception of type " << GetTypeName(typeid(err));
5417	*listener << " ";
5418	#else
5419	*listener << "throws an std::exception-derived type ";
5420	#endif
5421	*listener << "with description \"" << err.what() << "\"";
5422	return false;
5423	} catch (...) {
5424	*listener << "throws an exception of an unknown type";
5425	return false;
5426	}
5427
5428	*listener << "does not throw any exception";
5429	return false;
5430	}
5431
5432	private:
5433	const Matcher<const Err&> matcher_;
5434	};
5435
5436	} // namespace internal
5437
5438	// Throws()
5439	// Throws(exceptionMatcher)
5440	// ThrowsMessage(messageMatcher)
5441	//
5442	// This matcher accepts a callable and verifies that when invoked, it throws
5443	// an exception with the given type and properties.
5444	//
5445	// Examples:
5446	//
5447	// EXPECT_THAT(
5448	// []() { throw std::runtime_error("message"); },
5449	// Throws<std::runtime_error>());
5450	//
5451	// EXPECT_THAT(
5452	// []() { throw std::runtime_error("message"); },
5453	// ThrowsMessage<std::runtime_error>(HasSubstr("message")));
5454	//
5455	// EXPECT_THAT(
5456	// []() { throw std::runtime_error("message"); },
5457	// Throws<std::runtime_error>(
5458	// Property(&std::runtime_error::what, HasSubstr("message"))));
5459
5460	template <typename Err>
5461	PolymorphicMatcher<internal::ExceptionMatcherImpl<Err>> Throws() {
5462	return MakePolymorphicMatcher(
5463	internal::ExceptionMatcherImpl<Err>(A<const Err&>()));
5464	}
5465
5466	template <typename Err, typename ExceptionMatcher>
5467	PolymorphicMatcher<internal::ExceptionMatcherImpl<Err>> Throws(
5468	const ExceptionMatcher& exception_matcher) {
5469	// Using matcher cast allows users to pass a matcher of a more broad type.
5470	// For example user may want to pass Matcher<std::exception>
5471	// to Throws<std::runtime_error>, or Matcher<int64> to Throws<int32>.
5472	return MakePolymorphicMatcher(internal::ExceptionMatcherImpl<Err>(
5473	SafeMatcherCast<const Err&>(exception_matcher)));
5474	}
5475
5476	template <typename Err, typename MessageMatcher>
5477	PolymorphicMatcher<internal::ExceptionMatcherImpl<Err>> ThrowsMessage(
5478	MessageMatcher&& message_matcher) {
5479	static_assert(std::is_base_of<std::exception, Err>::value,
5480	"expected an std::exception-derived type");
5481	return Throws<Err>(internal::WithWhat(
5482	MatcherCast<std::string>(std::forward<MessageMatcher>(message_matcher))));
5483	}
5484
5485	#endif // GTEST_HAS_EXCEPTIONS
5486
5487	// These macros allow using matchers to check values in Google Test
5488	// tests. ASSERT_THAT(value, matcher) and EXPECT_THAT(value, matcher)
5489	// succeed if and only if the value matches the matcher. If the assertion
5490	// fails, the value and the description of the matcher will be printed.
5491	#define ASSERT_THAT(value, matcher) \
5492	ASSERT_PRED_FORMAT1( \
5493	::testing::internal::MakePredicateFormatterFromMatcher(matcher), value)
5494	#define EXPECT_THAT(value, matcher) \
5495	EXPECT_PRED_FORMAT1( \
5496	::testing::internal::MakePredicateFormatterFromMatcher(matcher), value)
5497
5498	// MATCHER* macros itself are listed below.
5499	#define MATCHER(name, description) \
5500	class name##Matcher \
5501	: public ::testing::internal::MatcherBaseImpl<name##Matcher> { \
5502	public: \
5503	template <typename arg_type> \
5504	class gmock_Impl : public ::testing::MatcherInterface<const arg_type&> { \
5505	public: \
5506	gmock_Impl() {} \
5507	bool MatchAndExplain( \
5508	const arg_type& arg, \
5509	::testing::MatchResultListener* result_listener) const override; \
5510	void DescribeTo(::std::ostream* gmock_os) const override { \
5511	*gmock_os << FormatDescription(false); \
5512	} \
5513	void DescribeNegationTo(::std::ostream* gmock_os) const override { \
5514	*gmock_os << FormatDescription(true); \
5515	} \
5516	\
5517	private: \
5518	::std::string FormatDescription(bool negation) const { \
5519	/* NOLINTNEXTLINE readability-redundant-string-init */ \
5520	::std::string gmock_description = (description); \
5521	if (!gmock_description.empty()) { \
5522	return gmock_description; \
5523	} \
5524	return ::testing::internal::FormatMatcherDescription(negation, #name, \
5525	{}, {}); \
5526	} \
5527	}; \
5528	}; \
5529	inline name##Matcher GMOCK_INTERNAL_WARNING_PUSH() \
5530	GMOCK_INTERNAL_WARNING_CLANG(ignored, "-Wunused-function") \
5531	GMOCK_INTERNAL_WARNING_CLANG(ignored, "-Wunused-member-function") \
5532	name GMOCK_INTERNAL_WARNING_POP()() { \
5533	return {}; \
5534	} \
5535	template <typename arg_type> \
5536	bool name##Matcher::gmock_Impl<arg_type>::MatchAndExplain( \
5537	const arg_type& arg, \
5538	::testing::MatchResultListener* result_listener GTEST_ATTRIBUTE_UNUSED_) \
5539	const
5540
5541	#define MATCHER_P(name, p0, description) \
5542	GMOCK_INTERNAL_MATCHER(name, name##MatcherP, description, (#p0), (p0))
5543	#define MATCHER_P2(name, p0, p1, description) \
5544	GMOCK_INTERNAL_MATCHER(name, name##MatcherP2, description, (#p0, #p1), \
5545	(p0, p1))
5546	#define MATCHER_P3(name, p0, p1, p2, description) \
5547	GMOCK_INTERNAL_MATCHER(name, name##MatcherP3, description, (#p0, #p1, #p2), \
5548	(p0, p1, p2))
5549	#define MATCHER_P4(name, p0, p1, p2, p3, description) \
5550	GMOCK_INTERNAL_MATCHER(name, name##MatcherP4, description, \
5551	(#p0, #p1, #p2, #p3), (p0, p1, p2, p3))
5552	#define MATCHER_P5(name, p0, p1, p2, p3, p4, description) \
5553	GMOCK_INTERNAL_MATCHER(name, name##MatcherP5, description, \
5554	(#p0, #p1, #p2, #p3, #p4), (p0, p1, p2, p3, p4))
5555	#define MATCHER_P6(name, p0, p1, p2, p3, p4, p5, description) \
5556	GMOCK_INTERNAL_MATCHER(name, name##MatcherP6, description, \
5557	(#p0, #p1, #p2, #p3, #p4, #p5), \
5558	(p0, p1, p2, p3, p4, p5))
5559	#define MATCHER_P7(name, p0, p1, p2, p3, p4, p5, p6, description) \
5560	GMOCK_INTERNAL_MATCHER(name, name##MatcherP7, description, \
5561	(#p0, #p1, #p2, #p3, #p4, #p5, #p6), \
5562	(p0, p1, p2, p3, p4, p5, p6))
5563	#define MATCHER_P8(name, p0, p1, p2, p3, p4, p5, p6, p7, description) \
5564	GMOCK_INTERNAL_MATCHER(name, name##MatcherP8, description, \
5565	(#p0, #p1, #p2, #p3, #p4, #p5, #p6, #p7), \
5566	(p0, p1, p2, p3, p4, p5, p6, p7))
5567	#define MATCHER_P9(name, p0, p1, p2, p3, p4, p5, p6, p7, p8, description) \
5568	GMOCK_INTERNAL_MATCHER(name, name##MatcherP9, description, \
5569	(#p0, #p1, #p2, #p3, #p4, #p5, #p6, #p7, #p8), \
5570	(p0, p1, p2, p3, p4, p5, p6, p7, p8))
5571	#define MATCHER_P10(name, p0, p1, p2, p3, p4, p5, p6, p7, p8, p9, description) \
5572	GMOCK_INTERNAL_MATCHER(name, name##MatcherP10, description, \
5573	(#p0, #p1, #p2, #p3, #p4, #p5, #p6, #p7, #p8, #p9), \
5574	(p0, p1, p2, p3, p4, p5, p6, p7, p8, p9))
5575
5576	#define GMOCK_INTERNAL_MATCHER(name, full_name, description, arg_names, args) \
5577	template <GMOCK_INTERNAL_MATCHER_TEMPLATE_PARAMS(args)> \
5578	class full_name : public ::testing::internal::MatcherBaseImpl< \
5579	full_name<GMOCK_INTERNAL_MATCHER_TYPE_PARAMS(args)>> { \
5580	public: \
5581	using full_name::MatcherBaseImpl::MatcherBaseImpl; \
5582	template <typename arg_type> \
5583	class gmock_Impl : public ::testing::MatcherInterface<const arg_type&> { \
5584	public: \
5585	explicit gmock_Impl(GMOCK_INTERNAL_MATCHER_FUNCTION_ARGS(args)) \
5586	: GMOCK_INTERNAL_MATCHER_FORWARD_ARGS(args) {} \
5587	bool MatchAndExplain( \
5588	const arg_type& arg, \
5589	::testing::MatchResultListener* result_listener) const override; \
5590	void DescribeTo(::std::ostream* gmock_os) const override { \
5591	*gmock_os << FormatDescription(false); \
5592	} \
5593	void DescribeNegationTo(::std::ostream* gmock_os) const override { \
5594	*gmock_os << FormatDescription(true); \
5595	} \
5596	GMOCK_INTERNAL_MATCHER_MEMBERS(args) \
5597	\
5598	private: \
5599	::std::string FormatDescription(bool negation) const { \
5600	::std::string gmock_description; \
5601	gmock_description = (description); \
5602	if (!gmock_description.empty()) { \
5603	return gmock_description; \
5604	} \
5605	return ::testing::internal::FormatMatcherDescription( \
5606	negation, #name, {GMOCK_PP_REMOVE_PARENS(arg_names)}, \
5607	::testing::internal::UniversalTersePrintTupleFieldsToStrings( \
5608	::std::tuple<GMOCK_INTERNAL_MATCHER_TYPE_PARAMS(args)>( \
5609	GMOCK_INTERNAL_MATCHER_MEMBERS_USAGE(args)))); \
5610	} \
5611	}; \
5612	}; \
5613	template <GMOCK_INTERNAL_MATCHER_TEMPLATE_PARAMS(args)> \
5614	inline full_name<GMOCK_INTERNAL_MATCHER_TYPE_PARAMS(args)> name( \
5615	GMOCK_INTERNAL_MATCHER_FUNCTION_ARGS(args)) { \
5616	return full_name<GMOCK_INTERNAL_MATCHER_TYPE_PARAMS(args)>( \
5617	GMOCK_INTERNAL_MATCHER_ARGS_USAGE(args)); \
5618	} \
5619	template <GMOCK_INTERNAL_MATCHER_TEMPLATE_PARAMS(args)> \
5620	template <typename arg_type> \
5621	bool full_name<GMOCK_INTERNAL_MATCHER_TYPE_PARAMS(args)>::gmock_Impl< \
5622	arg_type>::MatchAndExplain(const arg_type& arg, \
5623	::testing::MatchResultListener* \
5624	result_listener GTEST_ATTRIBUTE_UNUSED_) \
5625	const
5626
5627	#define GMOCK_INTERNAL_MATCHER_TEMPLATE_PARAMS(args) \
5628	GMOCK_PP_TAIL( \
5629	GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_MATCHER_TEMPLATE_PARAM, , args))
5630	#define GMOCK_INTERNAL_MATCHER_TEMPLATE_PARAM(i_unused, data_unused, arg) \
5631	, typename arg##_type
5632
5633	#define GMOCK_INTERNAL_MATCHER_TYPE_PARAMS(args) \
5634	GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_MATCHER_TYPE_PARAM, , args))
5635	#define GMOCK_INTERNAL_MATCHER_TYPE_PARAM(i_unused, data_unused, arg) \
5636	, arg##_type
5637
5638	#define GMOCK_INTERNAL_MATCHER_FUNCTION_ARGS(args) \
5639	GMOCK_PP_TAIL(dummy_first GMOCK_PP_FOR_EACH( \
5640	GMOCK_INTERNAL_MATCHER_FUNCTION_ARG, , args))
5641	#define GMOCK_INTERNAL_MATCHER_FUNCTION_ARG(i, data_unused, arg) \
5642	, arg##_type gmock_p##i
5643
5644	#define GMOCK_INTERNAL_MATCHER_FORWARD_ARGS(args) \
5645	GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_MATCHER_FORWARD_ARG, , args))
5646	#define GMOCK_INTERNAL_MATCHER_FORWARD_ARG(i, data_unused, arg) \
5647	, arg(::std::forward<arg##_type>(gmock_p##i))
5648
5649	#define GMOCK_INTERNAL_MATCHER_MEMBERS(args) \
5650	GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_MATCHER_MEMBER, , args)
5651	#define GMOCK_INTERNAL_MATCHER_MEMBER(i_unused, data_unused, arg) \
5652	const arg##_type arg;
5653
5654	#define GMOCK_INTERNAL_MATCHER_MEMBERS_USAGE(args) \
5655	GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_MATCHER_MEMBER_USAGE, , args))
5656	#define GMOCK_INTERNAL_MATCHER_MEMBER_USAGE(i_unused, data_unused, arg) , arg
5657
5658	#define GMOCK_INTERNAL_MATCHER_ARGS_USAGE(args) \
5659	GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_MATCHER_ARG_USAGE, , args))
5660	#define GMOCK_INTERNAL_MATCHER_ARG_USAGE(i, data_unused, arg_unused) \
5661	, gmock_p##i
5662
5663	// To prevent ADL on certain functions we put them on a separate namespace.
5664	using namespace no_adl; // NOLINT
5665
5666	} // namespace testing
5667
5668	GTEST_DISABLE_MSC_WARNINGS_POP_() // 4251 5046
5669
5670	// Include any custom callback matchers added by the local installation.
5671	// We must include this header at the end to make sure it can use the
5672	// declarations from this file.
5673	#include "gmock/internal/custom/gmock-matchers.h"
5674
5675	#endif // GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_MATCHERS_H_
5676