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29
30// The Google C++ Testing and Mocking Framework (Google Test)
31//
32// This file implements just enough of the matcher interface to allow
33// EXPECT_DEATH and friends to accept a matcher argument.
34
35// IWYU pragma: private, include "gtest/gtest.h"
36// IWYU pragma: friend gtest/.*
37// IWYU pragma: friend gmock/.*
38
39#ifndef GOOGLETEST_INCLUDE_GTEST_GTEST_MATCHERS_H_
40#define GOOGLETEST_INCLUDE_GTEST_GTEST_MATCHERS_H_
41
42#include <atomic>
43#include <functional>
44#include <memory>
45#include <ostream>
46#include <string>
47#include <type_traits>
48
49#include "gtest/gtest-printers.h"
50#include "gtest/internal/gtest-internal.h"
51#include "gtest/internal/gtest-port.h"
52
53// MSVC warning C5046 is new as of VS2017 version 15.8.
54#if defined(_MSC_VER) && _MSC_VER >= 1915
55#define GTEST_MAYBE_5046_ 5046
56#else
57#define GTEST_MAYBE_5046_
58#endif
59
60GTEST_DISABLE_MSC_WARNINGS_PUSH_(
61 4251 GTEST_MAYBE_5046_ /* class A needs to have dll-interface to be used by
62 clients of class B */
63 /* Symbol involving type with internal linkage not defined */)
64
65namespace testing {
66
67// To implement a matcher Foo for type T, define:
68// 1. a class FooMatcherMatcher that implements the matcher interface:
69// using is_gtest_matcher = void;
70// bool MatchAndExplain(const T&, std::ostream*);
71// (MatchResultListener* can also be used instead of std::ostream*)
72// void DescribeTo(std::ostream*);
73// void DescribeNegationTo(std::ostream*);
74//
75// 2. a factory function that creates a Matcher<T> object from a
76// FooMatcherMatcher.
77
78class MatchResultListener {
79 public:
80 // Creates a listener object with the given underlying ostream. The
81 // listener does not own the ostream, and does not dereference it
82 // in the constructor or destructor.
83 explicit MatchResultListener(::std::ostream* os) : stream_(os) {}
84 virtual ~MatchResultListener() = 0; // Makes this class abstract.
85
86 // Streams x to the underlying ostream; does nothing if the ostream
87 // is NULL.
88 template <typename T>
89 MatchResultListener& operator<<(const T& x) {
90 if (stream_ != nullptr) *stream_ << x;
91 return *this;
92 }
93
94 // Returns the underlying ostream.
95 ::std::ostream* stream() { return stream_; }
96
97 // Returns true if and only if the listener is interested in an explanation
98 // of the match result. A matcher's MatchAndExplain() method can use
99 // this information to avoid generating the explanation when no one
100 // intends to hear it.
101 bool IsInterested() const { return stream_ != nullptr; }
102
103 private:
104 ::std::ostream* const stream_;
105
106 MatchResultListener(const MatchResultListener&) = delete;
107 MatchResultListener& operator=(const MatchResultListener&) = delete;
108};
109
110inline MatchResultListener::~MatchResultListener() = default;
111
112// An instance of a subclass of this knows how to describe itself as a
113// matcher.
114class GTEST_API_ MatcherDescriberInterface {
115 public:
116 virtual ~MatcherDescriberInterface() = default;
117
118 // Describes this matcher to an ostream. The function should print
119 // a verb phrase that describes the property a value matching this
120 // matcher should have. The subject of the verb phrase is the value
121 // being matched. For example, the DescribeTo() method of the Gt(7)
122 // matcher prints "is greater than 7".
123 virtual void DescribeTo(::std::ostream* os) const = 0;
124
125 // Describes the negation of this matcher to an ostream. For
126 // example, if the description of this matcher is "is greater than
127 // 7", the negated description could be "is not greater than 7".
128 // You are not required to override this when implementing
129 // MatcherInterface, but it is highly advised so that your matcher
130 // can produce good error messages.
131 virtual void DescribeNegationTo(::std::ostream* os) const {
132 *os << "not (";
133 DescribeTo(os);
134 *os << ")";
135 }
136};
137
138// The implementation of a matcher.
139template <typename T>
140class MatcherInterface : public MatcherDescriberInterface {
141 public:
142 // Returns true if and only if the matcher matches x; also explains the
143 // match result to 'listener' if necessary (see the next paragraph), in
144 // the form of a non-restrictive relative clause ("which ...",
145 // "whose ...", etc) that describes x. For example, the
146 // MatchAndExplain() method of the Pointee(...) matcher should
147 // generate an explanation like "which points to ...".
148 //
149 // Implementations of MatchAndExplain() should add an explanation of
150 // the match result *if and only if* they can provide additional
151 // information that's not already present (or not obvious) in the
152 // print-out of x and the matcher's description. Whether the match
153 // succeeds is not a factor in deciding whether an explanation is
154 // needed, as sometimes the caller needs to print a failure message
155 // when the match succeeds (e.g. when the matcher is used inside
156 // Not()).
157 //
158 // For example, a "has at least 10 elements" matcher should explain
159 // what the actual element count is, regardless of the match result,
160 // as it is useful information to the reader; on the other hand, an
161 // "is empty" matcher probably only needs to explain what the actual
162 // size is when the match fails, as it's redundant to say that the
163 // size is 0 when the value is already known to be empty.
164 //
165 // You should override this method when defining a new matcher.
166 //
167 // It's the responsibility of the caller (Google Test) to guarantee
168 // that 'listener' is not NULL. This helps to simplify a matcher's
169 // implementation when it doesn't care about the performance, as it
170 // can talk to 'listener' without checking its validity first.
171 // However, in order to implement dummy listeners efficiently,
172 // listener->stream() may be NULL.
173 virtual bool MatchAndExplain(T x, MatchResultListener* listener) const = 0;
174
175 // Inherits these methods from MatcherDescriberInterface:
176 // virtual void DescribeTo(::std::ostream* os) const = 0;
177 // virtual void DescribeNegationTo(::std::ostream* os) const;
178};
179
180namespace internal {
181
182// A match result listener that ignores the explanation.
183class DummyMatchResultListener : public MatchResultListener {
184 public:
185 DummyMatchResultListener() : MatchResultListener(nullptr) {}
186
187 private:
188 DummyMatchResultListener(const DummyMatchResultListener&) = delete;
189 DummyMatchResultListener& operator=(const DummyMatchResultListener&) = delete;
190};
191
192// A match result listener that forwards the explanation to a given
193// ostream. The difference between this and MatchResultListener is
194// that the former is concrete.
195class StreamMatchResultListener : public MatchResultListener {
196 public:
197 explicit StreamMatchResultListener(::std::ostream* os)
198 : MatchResultListener(os) {}
199
200 private:
201 StreamMatchResultListener(const StreamMatchResultListener&) = delete;
202 StreamMatchResultListener& operator=(const StreamMatchResultListener&) =
203 delete;
204};
205
206struct SharedPayloadBase {
207 std::atomic<int> ref{1};
208 void Ref() { ref.fetch_add(i: 1, m: std::memory_order_relaxed); }
209 bool Unref() { return ref.fetch_sub(i: 1, m: std::memory_order_acq_rel) == 1; }
210};
211
212template <typename T>
213struct SharedPayload : SharedPayloadBase {
214 explicit SharedPayload(const T& v) : value(v) {}
215 explicit SharedPayload(T&& v) : value(std::move(v)) {}
216
217 static void Destroy(SharedPayloadBase* shared) {
218 delete static_cast<SharedPayload*>(shared);
219 }
220
221 T value;
222};
223
224// An internal class for implementing Matcher<T>, which will derive
225// from it. We put functionalities common to all Matcher<T>
226// specializations here to avoid code duplication.
227template <typename T>
228class MatcherBase : private MatcherDescriberInterface {
229 public:
230 // Returns true if and only if the matcher matches x; also explains the
231 // match result to 'listener'.
232 bool MatchAndExplain(const T& x, MatchResultListener* listener) const {
233 GTEST_CHECK_(vtable_ != nullptr);
234 return vtable_->match_and_explain(*this, x, listener);
235 }
236
237 // Returns true if and only if this matcher matches x.
238 bool Matches(const T& x) const {
239 DummyMatchResultListener dummy;
240 return MatchAndExplain(x, listener: &dummy);
241 }
242
243 // Describes this matcher to an ostream.
244 void DescribeTo(::std::ostream* os) const final {
245 GTEST_CHECK_(vtable_ != nullptr);
246 vtable_->describe(*this, os, false);
247 }
248
249 // Describes the negation of this matcher to an ostream.
250 void DescribeNegationTo(::std::ostream* os) const final {
251 GTEST_CHECK_(vtable_ != nullptr);
252 vtable_->describe(*this, os, true);
253 }
254
255 // Explains why x matches, or doesn't match, the matcher.
256 void ExplainMatchResultTo(const T& x, ::std::ostream* os) const {
257 StreamMatchResultListener listener(os);
258 MatchAndExplain(x, listener: &listener);
259 }
260
261 // Returns the describer for this matcher object; retains ownership
262 // of the describer, which is only guaranteed to be alive when
263 // this matcher object is alive.
264 const MatcherDescriberInterface* GetDescriber() const {
265 if (vtable_ == nullptr) return nullptr;
266 return vtable_->get_describer(*this);
267 }
268
269 protected:
270 MatcherBase() : vtable_(nullptr), buffer_() {}
271
272 // Constructs a matcher from its implementation.
273 template <typename U>
274 explicit MatcherBase(const MatcherInterface<U>* impl)
275 : vtable_(nullptr), buffer_() {
276 Init(impl);
277 }
278
279 template <typename M, typename = typename std::remove_reference<
280 M>::type::is_gtest_matcher>
281 MatcherBase(M&& m) : vtable_(nullptr), buffer_() { // NOLINT
282 Init(std::forward<M>(m));
283 }
284
285 MatcherBase(const MatcherBase& other)
286 : vtable_(other.vtable_), buffer_(other.buffer_) {
287 if (IsShared()) buffer_.shared->Ref();
288 }
289
290 MatcherBase& operator=(const MatcherBase& other) {
291 if (this == &other) return *this;
292 Destroy();
293 vtable_ = other.vtable_;
294 buffer_ = other.buffer_;
295 if (IsShared()) buffer_.shared->Ref();
296 return *this;
297 }
298
299 MatcherBase(MatcherBase&& other)
300 : vtable_(other.vtable_), buffer_(other.buffer_) {
301 other.vtable_ = nullptr;
302 }
303
304 MatcherBase& operator=(MatcherBase&& other) {
305 if (this == &other) return *this;
306 Destroy();
307 vtable_ = other.vtable_;
308 buffer_ = other.buffer_;
309 other.vtable_ = nullptr;
310 return *this;
311 }
312
313 ~MatcherBase() override { Destroy(); }
314
315 private:
316 struct VTable {
317 bool (*match_and_explain)(const MatcherBase&, const T&,
318 MatchResultListener*);
319 void (*describe)(const MatcherBase&, std::ostream*, bool negation);
320 // Returns the captured object if it implements the interface, otherwise
321 // returns the MatcherBase itself.
322 const MatcherDescriberInterface* (*get_describer)(const MatcherBase&);
323 // Called on shared instances when the reference count reaches 0.
324 void (*shared_destroy)(SharedPayloadBase*);
325 };
326
327 bool IsShared() const {
328 return vtable_ != nullptr && vtable_->shared_destroy != nullptr;
329 }
330
331 // If the implementation uses a listener, call that.
332 template <typename P>
333 static auto MatchAndExplainImpl(const MatcherBase& m, const T& value,
334 MatchResultListener* listener)
335 -> decltype(P::Get(m).MatchAndExplain(value, listener->stream())) {
336 return P::Get(m).MatchAndExplain(value, listener->stream());
337 }
338
339 template <typename P>
340 static auto MatchAndExplainImpl(const MatcherBase& m, const T& value,
341 MatchResultListener* listener)
342 -> decltype(P::Get(m).MatchAndExplain(value, listener)) {
343 return P::Get(m).MatchAndExplain(value, listener);
344 }
345
346 template <typename P>
347 static void DescribeImpl(const MatcherBase& m, std::ostream* os,
348 bool negation) {
349 if (negation) {
350 P::Get(m).DescribeNegationTo(os);
351 } else {
352 P::Get(m).DescribeTo(os);
353 }
354 }
355
356 template <typename P>
357 static const MatcherDescriberInterface* GetDescriberImpl(
358 const MatcherBase& m) {
359 // If the impl is a MatcherDescriberInterface, then return it.
360 // Otherwise use MatcherBase itself.
361 // This allows us to implement the GetDescriber() function without support
362 // from the impl, but some users really want to get their impl back when
363 // they call GetDescriber().
364 // We use std::get on a tuple as a workaround of not having `if constexpr`.
365 return std::get<(
366 std::is_convertible<decltype(&P::Get(m)),
367 const MatcherDescriberInterface*>::value
368 ? 1
369 : 0)>(std::make_tuple(&m, &P::Get(m)));
370 }
371
372 template <typename P>
373 const VTable* GetVTable() {
374 static constexpr VTable kVTable = {&MatchAndExplainImpl<P>,
375 &DescribeImpl<P>, &GetDescriberImpl<P>,
376 P::shared_destroy};
377 return &kVTable;
378 }
379
380 union Buffer {
381 // Add some types to give Buffer some common alignment/size use cases.
382 void* ptr;
383 double d;
384 int64_t i;
385 // And add one for the out-of-line cases.
386 SharedPayloadBase* shared;
387 };
388
389 void Destroy() {
390 if (IsShared() && buffer_.shared->Unref()) {
391 vtable_->shared_destroy(buffer_.shared);
392 }
393 }
394
395 template <typename M>
396 static constexpr bool IsInlined() {
397 return sizeof(M) <= sizeof(Buffer) && alignof(M) <= alignof(Buffer) &&
398 std::is_trivially_copy_constructible<M>::value &&
399 std::is_trivially_destructible<M>::value;
400 }
401
402 template <typename M, bool = MatcherBase::IsInlined<M>()>
403 struct ValuePolicy {
404 static const M& Get(const MatcherBase& m) {
405 // When inlined along with Init, need to be explicit to avoid violating
406 // strict aliasing rules.
407 const M* ptr =
408 static_cast<const M*>(static_cast<const void*>(&m.buffer_));
409 return *ptr;
410 }
411 static void Init(MatcherBase& m, M impl) {
412 ::new (static_cast<void*>(&m.buffer_)) M(impl);
413 }
414 static constexpr auto shared_destroy = nullptr;
415 };
416
417 template <typename M>
418 struct ValuePolicy<M, false> {
419 using Shared = SharedPayload<M>;
420 static const M& Get(const MatcherBase& m) {
421 return static_cast<Shared*>(m.buffer_.shared)->value;
422 }
423 template <typename Arg>
424 static void Init(MatcherBase& m, Arg&& arg) {
425 m.buffer_.shared = new Shared(std::forward<Arg>(arg));
426 }
427 static constexpr auto shared_destroy = &Shared::Destroy;
428 };
429
430 template <typename U, bool B>
431 struct ValuePolicy<const MatcherInterface<U>*, B> {
432 using M = const MatcherInterface<U>;
433 using Shared = SharedPayload<std::unique_ptr<M>>;
434 static const M& Get(const MatcherBase& m) {
435 return *static_cast<Shared*>(m.buffer_.shared)->value;
436 }
437 static void Init(MatcherBase& m, M* impl) {
438 m.buffer_.shared = new Shared(std::unique_ptr<M>(impl));
439 }
440
441 static constexpr auto shared_destroy = &Shared::Destroy;
442 };
443
444 template <typename M>
445 void Init(M&& m) {
446 using MM = typename std::decay<M>::type;
447 using Policy = ValuePolicy<MM>;
448 vtable_ = GetVTable<Policy>();
449 Policy::Init(*this, std::forward<M>(m));
450 }
451
452 const VTable* vtable_;
453 Buffer buffer_;
454};
455
456} // namespace internal
457
458// A Matcher<T> is a copyable and IMMUTABLE (except by assignment)
459// object that can check whether a value of type T matches. The
460// implementation of Matcher<T> is just a std::shared_ptr to const
461// MatcherInterface<T>. Don't inherit from Matcher!
462template <typename T>
463class Matcher : public internal::MatcherBase<T> {
464 public:
465 // Constructs a null matcher. Needed for storing Matcher objects in STL
466 // containers. A default-constructed matcher is not yet initialized. You
467 // cannot use it until a valid value has been assigned to it.
468 explicit Matcher() {} // NOLINT
469
470 // Constructs a matcher from its implementation.
471 explicit Matcher(const MatcherInterface<const T&>* impl)
472 : internal::MatcherBase<T>(impl) {}
473
474 template <typename U>
475 explicit Matcher(
476 const MatcherInterface<U>* impl,
477 typename std::enable_if<!std::is_same<U, const U&>::value>::type* =
478 nullptr)
479 : internal::MatcherBase<T>(impl) {}
480
481 template <typename M, typename = typename std::remove_reference<
482 M>::type::is_gtest_matcher>
483 Matcher(M&& m) : internal::MatcherBase<T>(std::forward<M>(m)) {} // NOLINT
484
485 // Implicit constructor here allows people to write
486 // EXPECT_CALL(foo, Bar(5)) instead of EXPECT_CALL(foo, Bar(Eq(5))) sometimes
487 Matcher(T value); // NOLINT
488};
489
490// The following two specializations allow the user to write str
491// instead of Eq(str) and "foo" instead of Eq("foo") when a std::string
492// matcher is expected.
493template <>
494class GTEST_API_ Matcher<const std::string&>
495 : public internal::MatcherBase<const std::string&> {
496 public:
497 Matcher() = default;
498
499 explicit Matcher(const MatcherInterface<const std::string&>* impl)
500 : internal::MatcherBase<const std::string&>(impl) {}
501
502 template <typename M, typename = typename std::remove_reference<
503 M>::type::is_gtest_matcher>
504 Matcher(M&& m) // NOLINT
505 : internal::MatcherBase<const std::string&>(std::forward<M>(m)) {}
506
507 // Allows the user to write str instead of Eq(str) sometimes, where
508 // str is a std::string object.
509 Matcher(const std::string& s); // NOLINT
510
511 // Allows the user to write "foo" instead of Eq("foo") sometimes.
512 Matcher(const char* s); // NOLINT
513};
514
515template <>
516class GTEST_API_ Matcher<std::string>
517 : public internal::MatcherBase<std::string> {
518 public:
519 Matcher() = default;
520
521 explicit Matcher(const MatcherInterface<const std::string&>* impl)
522 : internal::MatcherBase<std::string>(impl) {}
523 explicit Matcher(const MatcherInterface<std::string>* impl)
524 : internal::MatcherBase<std::string>(impl) {}
525
526 template <typename M, typename = typename std::remove_reference<
527 M>::type::is_gtest_matcher>
528 Matcher(M&& m) // NOLINT
529 : internal::MatcherBase<std::string>(std::forward<M>(m)) {}
530
531 // Allows the user to write str instead of Eq(str) sometimes, where
532 // str is a string object.
533 Matcher(const std::string& s); // NOLINT
534
535 // Allows the user to write "foo" instead of Eq("foo") sometimes.
536 Matcher(const char* s); // NOLINT
537};
538
539#if GTEST_INTERNAL_HAS_STRING_VIEW
540// The following two specializations allow the user to write str
541// instead of Eq(str) and "foo" instead of Eq("foo") when a absl::string_view
542// matcher is expected.
543template <>
544class GTEST_API_ Matcher<const internal::StringView&>
545 : public internal::MatcherBase<const internal::StringView&> {
546 public:
547 Matcher() = default;
548
549 explicit Matcher(const MatcherInterface<const internal::StringView&>* impl)
550 : internal::MatcherBase<const internal::StringView&>(impl) {}
551
552 template <typename M, typename = typename std::remove_reference<
553 M>::type::is_gtest_matcher>
554 Matcher(M&& m) // NOLINT
555 : internal::MatcherBase<const internal::StringView&>(std::forward<M>(m)) {
556 }
557
558 // Allows the user to write str instead of Eq(str) sometimes, where
559 // str is a std::string object.
560 Matcher(const std::string& s); // NOLINT
561
562 // Allows the user to write "foo" instead of Eq("foo") sometimes.
563 Matcher(const char* s); // NOLINT
564
565 // Allows the user to pass absl::string_views or std::string_views directly.
566 Matcher(internal::StringView s); // NOLINT
567};
568
569template <>
570class GTEST_API_ Matcher<internal::StringView>
571 : public internal::MatcherBase<internal::StringView> {
572 public:
573 Matcher() = default;
574
575 explicit Matcher(const MatcherInterface<const internal::StringView&>* impl)
576 : internal::MatcherBase<internal::StringView>(impl) {}
577 explicit Matcher(const MatcherInterface<internal::StringView>* impl)
578 : internal::MatcherBase<internal::StringView>(impl) {}
579
580 template <typename M, typename = typename std::remove_reference<
581 M>::type::is_gtest_matcher>
582 Matcher(M&& m) // NOLINT
583 : internal::MatcherBase<internal::StringView>(std::forward<M>(m)) {}
584
585 // Allows the user to write str instead of Eq(str) sometimes, where
586 // str is a std::string object.
587 Matcher(const std::string& s); // NOLINT
588
589 // Allows the user to write "foo" instead of Eq("foo") sometimes.
590 Matcher(const char* s); // NOLINT
591
592 // Allows the user to pass absl::string_views or std::string_views directly.
593 Matcher(internal::StringView s); // NOLINT
594};
595#endif // GTEST_INTERNAL_HAS_STRING_VIEW
596
597// Prints a matcher in a human-readable format.
598template <typename T>
599std::ostream& operator<<(std::ostream& os, const Matcher<T>& matcher) {
600 matcher.DescribeTo(&os);
601 return os;
602}
603
604// The PolymorphicMatcher class template makes it easy to implement a
605// polymorphic matcher (i.e. a matcher that can match values of more
606// than one type, e.g. Eq(n) and NotNull()).
607//
608// To define a polymorphic matcher, a user should provide an Impl
609// class that has a DescribeTo() method and a DescribeNegationTo()
610// method, and define a member function (or member function template)
611//
612// bool MatchAndExplain(const Value& value,
613// MatchResultListener* listener) const;
614//
615// See the definition of NotNull() for a complete example.
616template <class Impl>
617class PolymorphicMatcher {
618 public:
619 explicit PolymorphicMatcher(const Impl& an_impl) : impl_(an_impl) {}
620
621 // Returns a mutable reference to the underlying matcher
622 // implementation object.
623 Impl& mutable_impl() { return impl_; }
624
625 // Returns an immutable reference to the underlying matcher
626 // implementation object.
627 const Impl& impl() const { return impl_; }
628
629 template <typename T>
630 operator Matcher<T>() const {
631 return Matcher<T>(new MonomorphicImpl<const T&>(impl_));
632 }
633
634 private:
635 template <typename T>
636 class MonomorphicImpl : public MatcherInterface<T> {
637 public:
638 explicit MonomorphicImpl(const Impl& impl) : impl_(impl) {}
639
640 void DescribeTo(::std::ostream* os) const override { impl_.DescribeTo(os); }
641
642 void DescribeNegationTo(::std::ostream* os) const override {
643 impl_.DescribeNegationTo(os);
644 }
645
646 bool MatchAndExplain(T x, MatchResultListener* listener) const override {
647 return impl_.MatchAndExplain(x, listener);
648 }
649
650 private:
651 const Impl impl_;
652 };
653
654 Impl impl_;
655};
656
657// Creates a matcher from its implementation.
658// DEPRECATED: Especially in the generic code, prefer:
659// Matcher<T>(new MyMatcherImpl<const T&>(...));
660//
661// MakeMatcher may create a Matcher that accepts its argument by value, which
662// leads to unnecessary copies & lack of support for non-copyable types.
663template <typename T>
664inline Matcher<T> MakeMatcher(const MatcherInterface<T>* impl) {
665 return Matcher<T>(impl);
666}
667
668// Creates a polymorphic matcher from its implementation. This is
669// easier to use than the PolymorphicMatcher<Impl> constructor as it
670// doesn't require you to explicitly write the template argument, e.g.
671//
672// MakePolymorphicMatcher(foo);
673// vs
674// PolymorphicMatcher<TypeOfFoo>(foo);
675template <class Impl>
676inline PolymorphicMatcher<Impl> MakePolymorphicMatcher(const Impl& impl) {
677 return PolymorphicMatcher<Impl>(impl);
678}
679
680namespace internal {
681// Implements a matcher that compares a given value with a
682// pre-supplied value using one of the ==, <=, <, etc, operators. The
683// two values being compared don't have to have the same type.
684//
685// The matcher defined here is polymorphic (for example, Eq(5) can be
686// used to match an int, a short, a double, etc). Therefore we use
687// a template type conversion operator in the implementation.
688//
689// The following template definition assumes that the Rhs parameter is
690// a "bare" type (i.e. neither 'const T' nor 'T&').
691template <typename D, typename Rhs, typename Op>
692class ComparisonBase {
693 public:
694 explicit ComparisonBase(const Rhs& rhs) : rhs_(rhs) {}
695
696 using is_gtest_matcher = void;
697
698 template <typename Lhs>
699 bool MatchAndExplain(const Lhs& lhs, std::ostream*) const {
700 return Op()(lhs, Unwrap(rhs_));
701 }
702 void DescribeTo(std::ostream* os) const {
703 *os << D::Desc() << " ";
704 UniversalPrint(Unwrap(rhs_), os);
705 }
706 void DescribeNegationTo(std::ostream* os) const {
707 *os << D::NegatedDesc() << " ";
708 UniversalPrint(Unwrap(rhs_), os);
709 }
710
711 private:
712 template <typename T>
713 static const T& Unwrap(const T& v) {
714 return v;
715 }
716 template <typename T>
717 static const T& Unwrap(std::reference_wrapper<T> v) {
718 return v;
719 }
720
721 Rhs rhs_;
722};
723
724template <typename Rhs>
725class EqMatcher : public ComparisonBase<EqMatcher<Rhs>, Rhs, std::equal_to<>> {
726 public:
727 explicit EqMatcher(const Rhs& rhs)
728 : ComparisonBase<EqMatcher<Rhs>, Rhs, std::equal_to<>>(rhs) {}
729 static const char* Desc() { return "is equal to"; }
730 static const char* NegatedDesc() { return "isn't equal to"; }
731};
732template <typename Rhs>
733class NeMatcher
734 : public ComparisonBase<NeMatcher<Rhs>, Rhs, std::not_equal_to<>> {
735 public:
736 explicit NeMatcher(const Rhs& rhs)
737 : ComparisonBase<NeMatcher<Rhs>, Rhs, std::not_equal_to<>>(rhs) {}
738 static const char* Desc() { return "isn't equal to"; }
739 static const char* NegatedDesc() { return "is equal to"; }
740};
741template <typename Rhs>
742class LtMatcher : public ComparisonBase<LtMatcher<Rhs>, Rhs, std::less<>> {
743 public:
744 explicit LtMatcher(const Rhs& rhs)
745 : ComparisonBase<LtMatcher<Rhs>, Rhs, std::less<>>(rhs) {}
746 static const char* Desc() { return "is <"; }
747 static const char* NegatedDesc() { return "isn't <"; }
748};
749template <typename Rhs>
750class GtMatcher : public ComparisonBase<GtMatcher<Rhs>, Rhs, std::greater<>> {
751 public:
752 explicit GtMatcher(const Rhs& rhs)
753 : ComparisonBase<GtMatcher<Rhs>, Rhs, std::greater<>>(rhs) {}
754 static const char* Desc() { return "is >"; }
755 static const char* NegatedDesc() { return "isn't >"; }
756};
757template <typename Rhs>
758class LeMatcher
759 : public ComparisonBase<LeMatcher<Rhs>, Rhs, std::less_equal<>> {
760 public:
761 explicit LeMatcher(const Rhs& rhs)
762 : ComparisonBase<LeMatcher<Rhs>, Rhs, std::less_equal<>>(rhs) {}
763 static const char* Desc() { return "is <="; }
764 static const char* NegatedDesc() { return "isn't <="; }
765};
766template <typename Rhs>
767class GeMatcher
768 : public ComparisonBase<GeMatcher<Rhs>, Rhs, std::greater_equal<>> {
769 public:
770 explicit GeMatcher(const Rhs& rhs)
771 : ComparisonBase<GeMatcher<Rhs>, Rhs, std::greater_equal<>>(rhs) {}
772 static const char* Desc() { return "is >="; }
773 static const char* NegatedDesc() { return "isn't >="; }
774};
775
776template <typename T, typename = typename std::enable_if<
777 std::is_constructible<std::string, T>::value>::type>
778using StringLike = T;
779
780// Implements polymorphic matchers MatchesRegex(regex) and
781// ContainsRegex(regex), which can be used as a Matcher<T> as long as
782// T can be converted to a string.
783class MatchesRegexMatcher {
784 public:
785 MatchesRegexMatcher(const RE* regex, bool full_match)
786 : regex_(regex), full_match_(full_match) {}
787
788#if GTEST_INTERNAL_HAS_STRING_VIEW
789 bool MatchAndExplain(const internal::StringView& s,
790 MatchResultListener* listener) const {
791 return MatchAndExplain(s: std::string(s), listener);
792 }
793#endif // GTEST_INTERNAL_HAS_STRING_VIEW
794
795 // Accepts pointer types, particularly:
796 // const char*
797 // char*
798 // const wchar_t*
799 // wchar_t*
800 template <typename CharType>
801 bool MatchAndExplain(CharType* s, MatchResultListener* listener) const {
802 return s != nullptr && MatchAndExplain(s: std::string(s), listener);
803 }
804
805 // Matches anything that can convert to std::string.
806 //
807 // This is a template, not just a plain function with const std::string&,
808 // because absl::string_view has some interfering non-explicit constructors.
809 template <class MatcheeStringType>
810 bool MatchAndExplain(const MatcheeStringType& s,
811 MatchResultListener* /* listener */) const {
812 const std::string s2(s);
813 return full_match_ ? RE::FullMatch(str: s2, re: *regex_)
814 : RE::PartialMatch(str: s2, re: *regex_);
815 }
816
817 void DescribeTo(::std::ostream* os) const {
818 *os << (full_match_ ? "matches" : "contains") << " regular expression ";
819 UniversalPrinter<std::string>::Print(value: regex_->pattern(), os);
820 }
821
822 void DescribeNegationTo(::std::ostream* os) const {
823 *os << "doesn't " << (full_match_ ? "match" : "contain")
824 << " regular expression ";
825 UniversalPrinter<std::string>::Print(value: regex_->pattern(), os);
826 }
827
828 private:
829 const std::shared_ptr<const RE> regex_;
830 const bool full_match_;
831};
832} // namespace internal
833
834// Matches a string that fully matches regular expression 'regex'.
835// The matcher takes ownership of 'regex'.
836inline PolymorphicMatcher<internal::MatchesRegexMatcher> MatchesRegex(
837 const internal::RE* regex) {
838 return MakePolymorphicMatcher(impl: internal::MatchesRegexMatcher(regex, true));
839}
840template <typename T = std::string>
841PolymorphicMatcher<internal::MatchesRegexMatcher> MatchesRegex(
842 const internal::StringLike<T>& regex) {
843 return MatchesRegex(regex: new internal::RE(std::string(regex)));
844}
845
846// Matches a string that contains regular expression 'regex'.
847// The matcher takes ownership of 'regex'.
848inline PolymorphicMatcher<internal::MatchesRegexMatcher> ContainsRegex(
849 const internal::RE* regex) {
850 return MakePolymorphicMatcher(impl: internal::MatchesRegexMatcher(regex, false));
851}
852template <typename T = std::string>
853PolymorphicMatcher<internal::MatchesRegexMatcher> ContainsRegex(
854 const internal::StringLike<T>& regex) {
855 return ContainsRegex(regex: new internal::RE(std::string(regex)));
856}
857
858// Creates a polymorphic matcher that matches anything equal to x.
859// Note: if the parameter of Eq() were declared as const T&, Eq("foo")
860// wouldn't compile.
861template <typename T>
862inline internal::EqMatcher<T> Eq(T x) {
863 return internal::EqMatcher<T>(x);
864}
865
866// Constructs a Matcher<T> from a 'value' of type T. The constructed
867// matcher matches any value that's equal to 'value'.
868template <typename T>
869Matcher<T>::Matcher(T value) {
870 *this = Eq(value);
871}
872
873// Creates a monomorphic matcher that matches anything with type Lhs
874// and equal to rhs. A user may need to use this instead of Eq(...)
875// in order to resolve an overloading ambiguity.
876//
877// TypedEq<T>(x) is just a convenient short-hand for Matcher<T>(Eq(x))
878// or Matcher<T>(x), but more readable than the latter.
879//
880// We could define similar monomorphic matchers for other comparison
881// operations (e.g. TypedLt, TypedGe, and etc), but decided not to do
882// it yet as those are used much less than Eq() in practice. A user
883// can always write Matcher<T>(Lt(5)) to be explicit about the type,
884// for example.
885template <typename Lhs, typename Rhs>
886inline Matcher<Lhs> TypedEq(const Rhs& rhs) {
887 return Eq(rhs);
888}
889
890// Creates a polymorphic matcher that matches anything >= x.
891template <typename Rhs>
892inline internal::GeMatcher<Rhs> Ge(Rhs x) {
893 return internal::GeMatcher<Rhs>(x);
894}
895
896// Creates a polymorphic matcher that matches anything > x.
897template <typename Rhs>
898inline internal::GtMatcher<Rhs> Gt(Rhs x) {
899 return internal::GtMatcher<Rhs>(x);
900}
901
902// Creates a polymorphic matcher that matches anything <= x.
903template <typename Rhs>
904inline internal::LeMatcher<Rhs> Le(Rhs x) {
905 return internal::LeMatcher<Rhs>(x);
906}
907
908// Creates a polymorphic matcher that matches anything < x.
909template <typename Rhs>
910inline internal::LtMatcher<Rhs> Lt(Rhs x) {
911 return internal::LtMatcher<Rhs>(x);
912}
913
914// Creates a polymorphic matcher that matches anything != x.
915template <typename Rhs>
916inline internal::NeMatcher<Rhs> Ne(Rhs x) {
917 return internal::NeMatcher<Rhs>(x);
918}
919} // namespace testing
920
921GTEST_DISABLE_MSC_WARNINGS_POP_() // 4251 5046
922
923#endif // GOOGLETEST_INCLUDE_GTEST_GTEST_MATCHERS_H_
924