1// Copyright 2007, Google Inc.
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are
6// met:
7//
8// * Redistributions of source code must retain the above copyright
9// notice, this list of conditions and the following disclaimer.
10// * Redistributions in binary form must reproduce the above
11// copyright notice, this list of conditions and the following disclaimer
12// in the documentation and/or other materials provided with the
13// distribution.
14// * Neither the name of Google Inc. nor the names of its
15// contributors may be used to endorse or promote products derived from
16// this software without specific prior written permission.
17//
18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30// Google Mock - a framework for writing C++ mock classes.
31//
32// The ACTION* family of macros can be used in a namespace scope to
33// define custom actions easily. The syntax:
34//
35// ACTION(name) { statements; }
36//
37// will define an action with the given name that executes the
38// statements. The value returned by the statements will be used as
39// the return value of the action. Inside the statements, you can
40// refer to the K-th (0-based) argument of the mock function by
41// 'argK', and refer to its type by 'argK_type'. For example:
42//
43// ACTION(IncrementArg1) {
44// arg1_type temp = arg1;
45// return ++(*temp);
46// }
47//
48// allows you to write
49//
50// ...WillOnce(IncrementArg1());
51//
52// You can also refer to the entire argument tuple and its type by
53// 'args' and 'args_type', and refer to the mock function type and its
54// return type by 'function_type' and 'return_type'.
55//
56// Note that you don't need to specify the types of the mock function
57// arguments. However rest assured that your code is still type-safe:
58// you'll get a compiler error if *arg1 doesn't support the ++
59// operator, or if the type of ++(*arg1) isn't compatible with the
60// mock function's return type, for example.
61//
62// Sometimes you'll want to parameterize the action. For that you can use
63// another macro:
64//
65// ACTION_P(name, param_name) { statements; }
66//
67// For example:
68//
69// ACTION_P(Add, n) { return arg0 + n; }
70//
71// will allow you to write:
72//
73// ...WillOnce(Add(5));
74//
75// Note that you don't need to provide the type of the parameter
76// either. If you need to reference the type of a parameter named
77// 'foo', you can write 'foo_type'. For example, in the body of
78// ACTION_P(Add, n) above, you can write 'n_type' to refer to the type
79// of 'n'.
80//
81// We also provide ACTION_P2, ACTION_P3, ..., up to ACTION_P10 to support
82// multi-parameter actions.
83//
84// For the purpose of typing, you can view
85//
86// ACTION_Pk(Foo, p1, ..., pk) { ... }
87//
88// as shorthand for
89//
90// template <typename p1_type, ..., typename pk_type>
91// FooActionPk<p1_type, ..., pk_type> Foo(p1_type p1, ..., pk_type pk) { ... }
92//
93// In particular, you can provide the template type arguments
94// explicitly when invoking Foo(), as in Foo<long, bool>(5, false);
95// although usually you can rely on the compiler to infer the types
96// for you automatically. You can assign the result of expression
97// Foo(p1, ..., pk) to a variable of type FooActionPk<p1_type, ...,
98// pk_type>. This can be useful when composing actions.
99//
100// You can also overload actions with different numbers of parameters:
101//
102// ACTION_P(Plus, a) { ... }
103// ACTION_P2(Plus, a, b) { ... }
104//
105// While it's tempting to always use the ACTION* macros when defining
106// a new action, you should also consider implementing ActionInterface
107// or using MakePolymorphicAction() instead, especially if you need to
108// use the action a lot. While these approaches require more work,
109// they give you more control on the types of the mock function
110// arguments and the action parameters, which in general leads to
111// better compiler error messages that pay off in the long run. They
112// also allow overloading actions based on parameter types (as opposed
113// to just based on the number of parameters).
114//
115// CAVEAT:
116//
117// ACTION*() can only be used in a namespace scope as templates cannot be
118// declared inside of a local class.
119// Users can, however, define any local functors (e.g. a lambda) that
120// can be used as actions.
121//
122// MORE INFORMATION:
123//
124// To learn more about using these macros, please search for 'ACTION' on
125// https://github.com/google/googletest/blob/main/docs/gmock_cook_book.md
126
127// IWYU pragma: private, include "gmock/gmock.h"
128// IWYU pragma: friend gmock/.*
129
130#ifndef GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
131#define GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
132
133#ifndef _WIN32_WCE
134#include <errno.h>
135#endif
136
137#include <algorithm>
138#include <functional>
139#include <memory>
140#include <string>
141#include <tuple>
142#include <type_traits>
143#include <utility>
144
145#include "gmock/internal/gmock-internal-utils.h"
146#include "gmock/internal/gmock-port.h"
147#include "gmock/internal/gmock-pp.h"
148
149GTEST_DISABLE_MSC_WARNINGS_PUSH_(4100)
150
151namespace testing {
152
153// To implement an action Foo, define:
154// 1. a class FooAction that implements the ActionInterface interface, and
155// 2. a factory function that creates an Action object from a
156// const FooAction*.
157//
158// The two-level delegation design follows that of Matcher, providing
159// consistency for extension developers. It also eases ownership
160// management as Action objects can now be copied like plain values.
161
162namespace internal {
163
164// BuiltInDefaultValueGetter<T, true>::Get() returns a
165// default-constructed T value. BuiltInDefaultValueGetter<T,
166// false>::Get() crashes with an error.
167//
168// This primary template is used when kDefaultConstructible is true.
169template <typename T, bool kDefaultConstructible>
170struct BuiltInDefaultValueGetter {
171 static T Get() { return T(); }
172};
173template <typename T>
174struct BuiltInDefaultValueGetter<T, false> {
175 static T Get() {
176 Assert(condition: false, __FILE__, __LINE__,
177 msg: "Default action undefined for the function return type.");
178 return internal::Invalid<T>();
179 // The above statement will never be reached, but is required in
180 // order for this function to compile.
181 }
182};
183
184// BuiltInDefaultValue<T>::Get() returns the "built-in" default value
185// for type T, which is NULL when T is a raw pointer type, 0 when T is
186// a numeric type, false when T is bool, or "" when T is string or
187// std::string. In addition, in C++11 and above, it turns a
188// default-constructed T value if T is default constructible. For any
189// other type T, the built-in default T value is undefined, and the
190// function will abort the process.
191template <typename T>
192class BuiltInDefaultValue {
193 public:
194 // This function returns true if and only if type T has a built-in default
195 // value.
196 static bool Exists() { return ::std::is_default_constructible<T>::value; }
197
198 static T Get() {
199 return BuiltInDefaultValueGetter<
200 T, ::std::is_default_constructible<T>::value>::Get();
201 }
202};
203
204// This partial specialization says that we use the same built-in
205// default value for T and const T.
206template <typename T>
207class BuiltInDefaultValue<const T> {
208 public:
209 static bool Exists() { return BuiltInDefaultValue<T>::Exists(); }
210 static T Get() { return BuiltInDefaultValue<T>::Get(); }
211};
212
213// This partial specialization defines the default values for pointer
214// types.
215template <typename T>
216class BuiltInDefaultValue<T*> {
217 public:
218 static bool Exists() { return true; }
219 static T* Get() { return nullptr; }
220};
221
222// The following specializations define the default values for
223// specific types we care about.
224#define GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(type, value) \
225 template <> \
226 class BuiltInDefaultValue<type> { \
227 public: \
228 static bool Exists() { return true; } \
229 static type Get() { return value; } \
230 }
231
232GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(void, ); // NOLINT
233GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(::std::string, "");
234GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(bool, false);
235GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned char, '\0');
236GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed char, '\0');
237GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(char, '\0');
238
239// There's no need for a default action for signed wchar_t, as that
240// type is the same as wchar_t for gcc, and invalid for MSVC.
241//
242// There's also no need for a default action for unsigned wchar_t, as
243// that type is the same as unsigned int for gcc, and invalid for
244// MSVC.
245#if GMOCK_WCHAR_T_IS_NATIVE_
246GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(wchar_t, 0U); // NOLINT
247#endif
248
249GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned short, 0U); // NOLINT
250GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed short, 0); // NOLINT
251GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned int, 0U);
252GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed int, 0);
253GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned long, 0UL); // NOLINT
254GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed long, 0L); // NOLINT
255GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned long long, 0); // NOLINT
256GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed long long, 0); // NOLINT
257GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(float, 0);
258GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(double, 0);
259
260#undef GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_
261
262// Partial implementations of metaprogramming types from the standard library
263// not available in C++11.
264
265template <typename P>
266struct negation
267 // NOLINTNEXTLINE
268 : std::integral_constant<bool, bool(!P::value)> {};
269
270// Base case: with zero predicates the answer is always true.
271template <typename...>
272struct conjunction : std::true_type {};
273
274// With a single predicate, the answer is that predicate.
275template <typename P1>
276struct conjunction<P1> : P1 {};
277
278// With multiple predicates the answer is the first predicate if that is false,
279// and we recurse otherwise.
280template <typename P1, typename... Ps>
281struct conjunction<P1, Ps...>
282 : std::conditional<bool(P1::value), conjunction<Ps...>, P1>::type {};
283
284template <typename...>
285struct disjunction : std::false_type {};
286
287template <typename P1>
288struct disjunction<P1> : P1 {};
289
290template <typename P1, typename... Ps>
291struct disjunction<P1, Ps...>
292 // NOLINTNEXTLINE
293 : std::conditional<!bool(P1::value), disjunction<Ps...>, P1>::type {};
294
295template <typename...>
296using void_t = void;
297
298// Detects whether an expression of type `From` can be implicitly converted to
299// `To` according to [conv]. In C++17, [conv]/3 defines this as follows:
300//
301// An expression e can be implicitly converted to a type T if and only if
302// the declaration T t=e; is well-formed, for some invented temporary
303// variable t ([dcl.init]).
304//
305// [conv]/2 implies we can use function argument passing to detect whether this
306// initialization is valid.
307//
308// Note that this is distinct from is_convertible, which requires this be valid:
309//
310// To test() {
311// return declval<From>();
312// }
313//
314// In particular, is_convertible doesn't give the correct answer when `To` and
315// `From` are the same non-moveable type since `declval<From>` will be an rvalue
316// reference, defeating the guaranteed copy elision that would otherwise make
317// this function work.
318//
319// REQUIRES: `From` is not cv void.
320template <typename From, typename To>
321struct is_implicitly_convertible {
322 private:
323 // A function that accepts a parameter of type T. This can be called with type
324 // U successfully only if U is implicitly convertible to T.
325 template <typename T>
326 static void Accept(T);
327
328 // A function that creates a value of type T.
329 template <typename T>
330 static T Make();
331
332 // An overload be selected when implicit conversion from T to To is possible.
333 template <typename T, typename = decltype(Accept<To>(Make<T>()))>
334 static std::true_type TestImplicitConversion(int);
335
336 // A fallback overload selected in all other cases.
337 template <typename T>
338 static std::false_type TestImplicitConversion(...);
339
340 public:
341 using type = decltype(TestImplicitConversion<From>(0));
342 static constexpr bool value = type::value;
343};
344
345// Like std::invoke_result_t from C++17, but works only for objects with call
346// operators (not e.g. member function pointers, which we don't need specific
347// support for in OnceAction because std::function deals with them).
348template <typename F, typename... Args>
349using call_result_t = decltype(std::declval<F>()(std::declval<Args>()...));
350
351template <typename Void, typename R, typename F, typename... Args>
352struct is_callable_r_impl : std::false_type {};
353
354// Specialize the struct for those template arguments where call_result_t is
355// well-formed. When it's not, the generic template above is chosen, resulting
356// in std::false_type.
357template <typename R, typename F, typename... Args>
358struct is_callable_r_impl<void_t<call_result_t<F, Args...>>, R, F, Args...>
359 : std::conditional<
360 std::is_void<R>::value, //
361 std::true_type, //
362 is_implicitly_convertible<call_result_t<F, Args...>, R>>::type {};
363
364// Like std::is_invocable_r from C++17, but works only for objects with call
365// operators. See the note on call_result_t.
366template <typename R, typename F, typename... Args>
367using is_callable_r = is_callable_r_impl<void, R, F, Args...>;
368
369// Like std::as_const from C++17.
370template <typename T>
371typename std::add_const<T>::type& as_const(T& t) {
372 return t;
373}
374
375} // namespace internal
376
377// Specialized for function types below.
378template <typename F>
379class OnceAction;
380
381// An action that can only be used once.
382//
383// This is accepted by WillOnce, which doesn't require the underlying action to
384// be copy-constructible (only move-constructible), and promises to invoke it as
385// an rvalue reference. This allows the action to work with move-only types like
386// std::move_only_function in a type-safe manner.
387//
388// For example:
389//
390// // Assume we have some API that needs to accept a unique pointer to some
391// // non-copyable object Foo.
392// void AcceptUniquePointer(std::unique_ptr<Foo> foo);
393//
394// // We can define an action that provides a Foo to that API. Because It
395// // has to give away its unique pointer, it must not be called more than
396// // once, so its call operator is &&-qualified.
397// struct ProvideFoo {
398// std::unique_ptr<Foo> foo;
399//
400// void operator()() && {
401// AcceptUniquePointer(std::move(Foo));
402// }
403// };
404//
405// // This action can be used with WillOnce.
406// EXPECT_CALL(mock, Call)
407// .WillOnce(ProvideFoo{std::make_unique<Foo>(...)});
408//
409// // But a call to WillRepeatedly will fail to compile. This is correct,
410// // since the action cannot correctly be used repeatedly.
411// EXPECT_CALL(mock, Call)
412// .WillRepeatedly(ProvideFoo{std::make_unique<Foo>(...)});
413//
414// A less-contrived example would be an action that returns an arbitrary type,
415// whose &&-qualified call operator is capable of dealing with move-only types.
416template <typename Result, typename... Args>
417class OnceAction<Result(Args...)> final {
418 private:
419 // True iff we can use the given callable type (or lvalue reference) directly
420 // via StdFunctionAdaptor.
421 template <typename Callable>
422 using IsDirectlyCompatible = internal::conjunction<
423 // It must be possible to capture the callable in StdFunctionAdaptor.
424 std::is_constructible<typename std::decay<Callable>::type, Callable>,
425 // The callable must be compatible with our signature.
426 internal::is_callable_r<Result, typename std::decay<Callable>::type,
427 Args...>>;
428
429 // True iff we can use the given callable type via StdFunctionAdaptor once we
430 // ignore incoming arguments.
431 template <typename Callable>
432 using IsCompatibleAfterIgnoringArguments = internal::conjunction<
433 // It must be possible to capture the callable in a lambda.
434 std::is_constructible<typename std::decay<Callable>::type, Callable>,
435 // The callable must be invocable with zero arguments, returning something
436 // convertible to Result.
437 internal::is_callable_r<Result, typename std::decay<Callable>::type>>;
438
439 public:
440 // Construct from a callable that is directly compatible with our mocked
441 // signature: it accepts our function type's arguments and returns something
442 // convertible to our result type.
443 template <typename Callable,
444 typename std::enable_if<
445 internal::conjunction<
446 // Teach clang on macOS that we're not talking about a
447 // copy/move constructor here. Otherwise it gets confused
448 // when checking the is_constructible requirement of our
449 // traits above.
450 internal::negation<std::is_same<
451 OnceAction, typename std::decay<Callable>::type>>,
452 IsDirectlyCompatible<Callable>> //
453 ::value,
454 int>::type = 0>
455 OnceAction(Callable&& callable) // NOLINT
456 : function_(StdFunctionAdaptor<typename std::decay<Callable>::type>(
457 {}, std::forward<Callable>(callable))) {}
458
459 // As above, but for a callable that ignores the mocked function's arguments.
460 template <typename Callable,
461 typename std::enable_if<
462 internal::conjunction<
463 // Teach clang on macOS that we're not talking about a
464 // copy/move constructor here. Otherwise it gets confused
465 // when checking the is_constructible requirement of our
466 // traits above.
467 internal::negation<std::is_same<
468 OnceAction, typename std::decay<Callable>::type>>,
469 // Exclude callables for which the overload above works.
470 // We'd rather provide the arguments if possible.
471 internal::negation<IsDirectlyCompatible<Callable>>,
472 IsCompatibleAfterIgnoringArguments<Callable>>::value,
473 int>::type = 0>
474 OnceAction(Callable&& callable) // NOLINT
475 // Call the constructor above with a callable
476 // that ignores the input arguments.
477 : OnceAction(IgnoreIncomingArguments<typename std::decay<Callable>::type>{
478 std::forward<Callable>(callable)}) {}
479
480 // We are naturally copyable because we store only an std::function, but
481 // semantically we should not be copyable.
482 OnceAction(const OnceAction&) = delete;
483 OnceAction& operator=(const OnceAction&) = delete;
484 OnceAction(OnceAction&&) = default;
485
486 // Invoke the underlying action callable with which we were constructed,
487 // handing it the supplied arguments.
488 Result Call(Args... args) && {
489 return function_(std::forward<Args>(args)...);
490 }
491
492 private:
493 // An adaptor that wraps a callable that is compatible with our signature and
494 // being invoked as an rvalue reference so that it can be used as an
495 // StdFunctionAdaptor. This throws away type safety, but that's fine because
496 // this is only used by WillOnce, which we know calls at most once.
497 //
498 // Once we have something like std::move_only_function from C++23, we can do
499 // away with this.
500 template <typename Callable>
501 class StdFunctionAdaptor final {
502 public:
503 // A tag indicating that the (otherwise universal) constructor is accepting
504 // the callable itself, instead of e.g. stealing calls for the move
505 // constructor.
506 struct CallableTag final {};
507
508 template <typename F>
509 explicit StdFunctionAdaptor(CallableTag, F&& callable)
510 : callable_(std::make_shared<Callable>(std::forward<F>(callable))) {}
511
512 // Rather than explicitly returning Result, we return whatever the wrapped
513 // callable returns. This allows for compatibility with existing uses like
514 // the following, when the mocked function returns void:
515 //
516 // EXPECT_CALL(mock_fn_, Call)
517 // .WillOnce([&] {
518 // [...]
519 // return 0;
520 // });
521 //
522 // Such a callable can be turned into std::function<void()>. If we use an
523 // explicit return type of Result here then it *doesn't* work with
524 // std::function, because we'll get a "void function should not return a
525 // value" error.
526 //
527 // We need not worry about incompatible result types because the SFINAE on
528 // OnceAction already checks this for us. std::is_invocable_r_v itself makes
529 // the same allowance for void result types.
530 template <typename... ArgRefs>
531 internal::call_result_t<Callable, ArgRefs...> operator()(
532 ArgRefs&&... args) const {
533 return std::move(*callable_)(std::forward<ArgRefs>(args)...);
534 }
535
536 private:
537 // We must put the callable on the heap so that we are copyable, which
538 // std::function needs.
539 std::shared_ptr<Callable> callable_;
540 };
541
542 // An adaptor that makes a callable that accepts zero arguments callable with
543 // our mocked arguments.
544 template <typename Callable>
545 struct IgnoreIncomingArguments {
546 internal::call_result_t<Callable> operator()(Args&&...) {
547 return std::move(callable)();
548 }
549
550 Callable callable;
551 };
552
553 std::function<Result(Args...)> function_;
554};
555
556// When an unexpected function call is encountered, Google Mock will
557// let it return a default value if the user has specified one for its
558// return type, or if the return type has a built-in default value;
559// otherwise Google Mock won't know what value to return and will have
560// to abort the process.
561//
562// The DefaultValue<T> class allows a user to specify the
563// default value for a type T that is both copyable and publicly
564// destructible (i.e. anything that can be used as a function return
565// type). The usage is:
566//
567// // Sets the default value for type T to be foo.
568// DefaultValue<T>::Set(foo);
569template <typename T>
570class DefaultValue {
571 public:
572 // Sets the default value for type T; requires T to be
573 // copy-constructable and have a public destructor.
574 static void Set(T x) {
575 delete producer_;
576 producer_ = new FixedValueProducer(x);
577 }
578
579 // Provides a factory function to be called to generate the default value.
580 // This method can be used even if T is only move-constructible, but it is not
581 // limited to that case.
582 typedef T (*FactoryFunction)();
583 static void SetFactory(FactoryFunction factory) {
584 delete producer_;
585 producer_ = new FactoryValueProducer(factory);
586 }
587
588 // Unsets the default value for type T.
589 static void Clear() {
590 delete producer_;
591 producer_ = nullptr;
592 }
593
594 // Returns true if and only if the user has set the default value for type T.
595 static bool IsSet() { return producer_ != nullptr; }
596
597 // Returns true if T has a default return value set by the user or there
598 // exists a built-in default value.
599 static bool Exists() {
600 return IsSet() || internal::BuiltInDefaultValue<T>::Exists();
601 }
602
603 // Returns the default value for type T if the user has set one;
604 // otherwise returns the built-in default value. Requires that Exists()
605 // is true, which ensures that the return value is well-defined.
606 static T Get() {
607 return producer_ == nullptr ? internal::BuiltInDefaultValue<T>::Get()
608 : producer_->Produce();
609 }
610
611 private:
612 class ValueProducer {
613 public:
614 virtual ~ValueProducer() = default;
615 virtual T Produce() = 0;
616 };
617
618 class FixedValueProducer : public ValueProducer {
619 public:
620 explicit FixedValueProducer(T value) : value_(value) {}
621 T Produce() override { return value_; }
622
623 private:
624 const T value_;
625 FixedValueProducer(const FixedValueProducer&) = delete;
626 FixedValueProducer& operator=(const FixedValueProducer&) = delete;
627 };
628
629 class FactoryValueProducer : public ValueProducer {
630 public:
631 explicit FactoryValueProducer(FactoryFunction factory)
632 : factory_(factory) {}
633 T Produce() override { return factory_(); }
634
635 private:
636 const FactoryFunction factory_;
637 FactoryValueProducer(const FactoryValueProducer&) = delete;
638 FactoryValueProducer& operator=(const FactoryValueProducer&) = delete;
639 };
640
641 static ValueProducer* producer_;
642};
643
644// This partial specialization allows a user to set default values for
645// reference types.
646template <typename T>
647class DefaultValue<T&> {
648 public:
649 // Sets the default value for type T&.
650 static void Set(T& x) { // NOLINT
651 address_ = &x;
652 }
653
654 // Unsets the default value for type T&.
655 static void Clear() { address_ = nullptr; }
656
657 // Returns true if and only if the user has set the default value for type T&.
658 static bool IsSet() { return address_ != nullptr; }
659
660 // Returns true if T has a default return value set by the user or there
661 // exists a built-in default value.
662 static bool Exists() {
663 return IsSet() || internal::BuiltInDefaultValue<T&>::Exists();
664 }
665
666 // Returns the default value for type T& if the user has set one;
667 // otherwise returns the built-in default value if there is one;
668 // otherwise aborts the process.
669 static T& Get() {
670 return address_ == nullptr ? internal::BuiltInDefaultValue<T&>::Get()
671 : *address_;
672 }
673
674 private:
675 static T* address_;
676};
677
678// This specialization allows DefaultValue<void>::Get() to
679// compile.
680template <>
681class DefaultValue<void> {
682 public:
683 static bool Exists() { return true; }
684 static void Get() {}
685};
686
687// Points to the user-set default value for type T.
688template <typename T>
689typename DefaultValue<T>::ValueProducer* DefaultValue<T>::producer_ = nullptr;
690
691// Points to the user-set default value for type T&.
692template <typename T>
693T* DefaultValue<T&>::address_ = nullptr;
694
695// Implement this interface to define an action for function type F.
696template <typename F>
697class ActionInterface {
698 public:
699 typedef typename internal::Function<F>::Result Result;
700 typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
701
702 ActionInterface() = default;
703 virtual ~ActionInterface() = default;
704
705 // Performs the action. This method is not const, as in general an
706 // action can have side effects and be stateful. For example, a
707 // get-the-next-element-from-the-collection action will need to
708 // remember the current element.
709 virtual Result Perform(const ArgumentTuple& args) = 0;
710
711 private:
712 ActionInterface(const ActionInterface&) = delete;
713 ActionInterface& operator=(const ActionInterface&) = delete;
714};
715
716template <typename F>
717class Action;
718
719// An Action<R(Args...)> is a copyable and IMMUTABLE (except by assignment)
720// object that represents an action to be taken when a mock function of type
721// R(Args...) is called. The implementation of Action<T> is just a
722// std::shared_ptr to const ActionInterface<T>. Don't inherit from Action! You
723// can view an object implementing ActionInterface<F> as a concrete action
724// (including its current state), and an Action<F> object as a handle to it.
725template <typename R, typename... Args>
726class Action<R(Args...)> {
727 private:
728 using F = R(Args...);
729
730 // Adapter class to allow constructing Action from a legacy ActionInterface.
731 // New code should create Actions from functors instead.
732 struct ActionAdapter {
733 // Adapter must be copyable to satisfy std::function requirements.
734 ::std::shared_ptr<ActionInterface<F>> impl_;
735
736 template <typename... InArgs>
737 typename internal::Function<F>::Result operator()(InArgs&&... args) {
738 return impl_->Perform(
739 ::std::forward_as_tuple(::std::forward<InArgs>(args)...));
740 }
741 };
742
743 template <typename G>
744 using IsCompatibleFunctor = std::is_constructible<std::function<F>, G>;
745
746 public:
747 typedef typename internal::Function<F>::Result Result;
748 typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
749
750 // Constructs a null Action. Needed for storing Action objects in
751 // STL containers.
752 Action() = default;
753
754 // Construct an Action from a specified callable.
755 // This cannot take std::function directly, because then Action would not be
756 // directly constructible from lambda (it would require two conversions).
757 template <
758 typename G,
759 typename = typename std::enable_if<internal::disjunction<
760 IsCompatibleFunctor<G>, std::is_constructible<std::function<Result()>,
761 G>>::value>::type>
762 Action(G&& fun) { // NOLINT
763 Init(::std::forward<G>(fun), IsCompatibleFunctor<G>());
764 }
765
766 // Constructs an Action from its implementation.
767 explicit Action(ActionInterface<F>* impl)
768 : fun_(ActionAdapter{::std::shared_ptr<ActionInterface<F>>(impl)}) {}
769
770 // This constructor allows us to turn an Action<Func> object into an
771 // Action<F>, as long as F's arguments can be implicitly converted
772 // to Func's and Func's return type can be implicitly converted to F's.
773 template <typename Func>
774 Action(const Action<Func>& action) // NOLINT
775 : fun_(action.fun_) {}
776
777 // Returns true if and only if this is the DoDefault() action.
778 bool IsDoDefault() const { return fun_ == nullptr; }
779
780 // Performs the action. Note that this method is const even though
781 // the corresponding method in ActionInterface is not. The reason
782 // is that a const Action<F> means that it cannot be re-bound to
783 // another concrete action, not that the concrete action it binds to
784 // cannot change state. (Think of the difference between a const
785 // pointer and a pointer to const.)
786 Result Perform(ArgumentTuple args) const {
787 if (IsDoDefault()) {
788 internal::IllegalDoDefault(__FILE__, __LINE__);
789 }
790 return internal::Apply(fun_, ::std::move(args));
791 }
792
793 // An action can be used as a OnceAction, since it's obviously safe to call it
794 // once.
795 operator OnceAction<F>() const { // NOLINT
796 // Return a OnceAction-compatible callable that calls Perform with the
797 // arguments it is provided. We could instead just return fun_, but then
798 // we'd need to handle the IsDoDefault() case separately.
799 struct OA {
800 Action<F> action;
801
802 R operator()(Args... args) && {
803 return action.Perform(
804 std::forward_as_tuple(std::forward<Args>(args)...));
805 }
806 };
807
808 return OA{*this};
809 }
810
811 private:
812 template <typename G>
813 friend class Action;
814
815 template <typename G>
816 void Init(G&& g, ::std::true_type) {
817 fun_ = ::std::forward<G>(g);
818 }
819
820 template <typename G>
821 void Init(G&& g, ::std::false_type) {
822 fun_ = IgnoreArgs<typename ::std::decay<G>::type>{::std::forward<G>(g)};
823 }
824
825 template <typename FunctionImpl>
826 struct IgnoreArgs {
827 template <typename... InArgs>
828 Result operator()(const InArgs&...) const {
829 return function_impl();
830 }
831
832 FunctionImpl function_impl;
833 };
834
835 // fun_ is an empty function if and only if this is the DoDefault() action.
836 ::std::function<F> fun_;
837};
838
839// The PolymorphicAction class template makes it easy to implement a
840// polymorphic action (i.e. an action that can be used in mock
841// functions of than one type, e.g. Return()).
842//
843// To define a polymorphic action, a user first provides a COPYABLE
844// implementation class that has a Perform() method template:
845//
846// class FooAction {
847// public:
848// template <typename Result, typename ArgumentTuple>
849// Result Perform(const ArgumentTuple& args) const {
850// // Processes the arguments and returns a result, using
851// // std::get<N>(args) to get the N-th (0-based) argument in the tuple.
852// }
853// ...
854// };
855//
856// Then the user creates the polymorphic action using
857// MakePolymorphicAction(object) where object has type FooAction. See
858// the definition of Return(void) and SetArgumentPointee<N>(value) for
859// complete examples.
860template <typename Impl>
861class PolymorphicAction {
862 public:
863 explicit PolymorphicAction(const Impl& impl) : impl_(impl) {}
864
865 template <typename F>
866 operator Action<F>() const {
867 return Action<F>(new MonomorphicImpl<F>(impl_));
868 }
869
870 private:
871 template <typename F>
872 class MonomorphicImpl : public ActionInterface<F> {
873 public:
874 typedef typename internal::Function<F>::Result Result;
875 typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
876
877 explicit MonomorphicImpl(const Impl& impl) : impl_(impl) {}
878
879 Result Perform(const ArgumentTuple& args) override {
880 return impl_.template Perform<Result>(args);
881 }
882
883 private:
884 Impl impl_;
885 };
886
887 Impl impl_;
888};
889
890// Creates an Action from its implementation and returns it. The
891// created Action object owns the implementation.
892template <typename F>
893Action<F> MakeAction(ActionInterface<F>* impl) {
894 return Action<F>(impl);
895}
896
897// Creates a polymorphic action from its implementation. This is
898// easier to use than the PolymorphicAction<Impl> constructor as it
899// doesn't require you to explicitly write the template argument, e.g.
900//
901// MakePolymorphicAction(foo);
902// vs
903// PolymorphicAction<TypeOfFoo>(foo);
904template <typename Impl>
905inline PolymorphicAction<Impl> MakePolymorphicAction(const Impl& impl) {
906 return PolymorphicAction<Impl>(impl);
907}
908
909namespace internal {
910
911// Helper struct to specialize ReturnAction to execute a move instead of a copy
912// on return. Useful for move-only types, but could be used on any type.
913template <typename T>
914struct ByMoveWrapper {
915 explicit ByMoveWrapper(T value) : payload(std::move(value)) {}
916 T payload;
917};
918
919// The general implementation of Return(R). Specializations follow below.
920template <typename R>
921class ReturnAction final {
922 public:
923 explicit ReturnAction(R value) : value_(std::move(value)) {}
924
925 template <typename U, typename... Args,
926 typename = typename std::enable_if<conjunction<
927 // See the requirements documented on Return.
928 negation<std::is_same<void, U>>, //
929 negation<std::is_reference<U>>, //
930 std::is_convertible<R, U>, //
931 std::is_move_constructible<U>>::value>::type>
932 operator OnceAction<U(Args...)>() && { // NOLINT
933 return Impl<U>(std::move(value_));
934 }
935
936 template <typename U, typename... Args,
937 typename = typename std::enable_if<conjunction<
938 // See the requirements documented on Return.
939 negation<std::is_same<void, U>>, //
940 negation<std::is_reference<U>>, //
941 std::is_convertible<const R&, U>, //
942 std::is_copy_constructible<U>>::value>::type>
943 operator Action<U(Args...)>() const { // NOLINT
944 return Impl<U>(value_);
945 }
946
947 private:
948 // Implements the Return(x) action for a mock function that returns type U.
949 template <typename U>
950 class Impl final {
951 public:
952 // The constructor used when the return value is allowed to move from the
953 // input value (i.e. we are converting to OnceAction).
954 explicit Impl(R&& input_value)
955 : state_(new State(std::move(input_value))) {}
956
957 // The constructor used when the return value is not allowed to move from
958 // the input value (i.e. we are converting to Action).
959 explicit Impl(const R& input_value) : state_(new State(input_value)) {}
960
961 U operator()() && { return std::move(state_->value); }
962 U operator()() const& { return state_->value; }
963
964 private:
965 // We put our state on the heap so that the compiler-generated copy/move
966 // constructors work correctly even when U is a reference-like type. This is
967 // necessary only because we eagerly create State::value (see the note on
968 // that symbol for details). If we instead had only the input value as a
969 // member then the default constructors would work fine.
970 //
971 // For example, when R is std::string and U is std::string_view, value is a
972 // reference to the string backed by input_value. The copy constructor would
973 // copy both, so that we wind up with a new input_value object (with the
974 // same contents) and a reference to the *old* input_value object rather
975 // than the new one.
976 struct State {
977 explicit State(const R& input_value_in)
978 : input_value(input_value_in),
979 // Make an implicit conversion to Result before initializing the U
980 // object we store, avoiding calling any explicit constructor of U
981 // from R.
982 //
983 // This simulates the language rules: a function with return type U
984 // that does `return R()` requires R to be implicitly convertible to
985 // U, and uses that path for the conversion, even U Result has an
986 // explicit constructor from R.
987 value(ImplicitCast_<U>(internal::as_const(input_value))) {}
988
989 // As above, but for the case where we're moving from the ReturnAction
990 // object because it's being used as a OnceAction.
991 explicit State(R&& input_value_in)
992 : input_value(std::move(input_value_in)),
993 // For the same reason as above we make an implicit conversion to U
994 // before initializing the value.
995 //
996 // Unlike above we provide the input value as an rvalue to the
997 // implicit conversion because this is a OnceAction: it's fine if it
998 // wants to consume the input value.
999 value(ImplicitCast_<U>(std::move(input_value))) {}
1000
1001 // A copy of the value originally provided by the user. We retain this in
1002 // addition to the value of the mock function's result type below in case
1003 // the latter is a reference-like type. See the std::string_view example
1004 // in the documentation on Return.
1005 R input_value;
1006
1007 // The value we actually return, as the type returned by the mock function
1008 // itself.
1009 //
1010 // We eagerly initialize this here, rather than lazily doing the implicit
1011 // conversion automatically each time Perform is called, for historical
1012 // reasons: in 2009-11, commit a070cbd91c (Google changelist 13540126)
1013 // made the Action<U()> conversion operator eagerly convert the R value to
1014 // U, but without keeping the R alive. This broke the use case discussed
1015 // in the documentation for Return, making reference-like types such as
1016 // std::string_view not safe to use as U where the input type R is a
1017 // value-like type such as std::string.
1018 //
1019 // The example the commit gave was not very clear, nor was the issue
1020 // thread (https://github.com/google/googlemock/issues/86), but it seems
1021 // the worry was about reference-like input types R that flatten to a
1022 // value-like type U when being implicitly converted. An example of this
1023 // is std::vector<bool>::reference, which is often a proxy type with an
1024 // reference to the underlying vector:
1025 //
1026 // // Helper method: have the mock function return bools according
1027 // // to the supplied script.
1028 // void SetActions(MockFunction<bool(size_t)>& mock,
1029 // const std::vector<bool>& script) {
1030 // for (size_t i = 0; i < script.size(); ++i) {
1031 // EXPECT_CALL(mock, Call(i)).WillOnce(Return(script[i]));
1032 // }
1033 // }
1034 //
1035 // TEST(Foo, Bar) {
1036 // // Set actions using a temporary vector, whose operator[]
1037 // // returns proxy objects that references that will be
1038 // // dangling once the call to SetActions finishes and the
1039 // // vector is destroyed.
1040 // MockFunction<bool(size_t)> mock;
1041 // SetActions(mock, {false, true});
1042 //
1043 // EXPECT_FALSE(mock.AsStdFunction()(0));
1044 // EXPECT_TRUE(mock.AsStdFunction()(1));
1045 // }
1046 //
1047 // This eager conversion helps with a simple case like this, but doesn't
1048 // fully make these types work in general. For example the following still
1049 // uses a dangling reference:
1050 //
1051 // TEST(Foo, Baz) {
1052 // MockFunction<std::vector<std::string>()> mock;
1053 //
1054 // // Return the same vector twice, and then the empty vector
1055 // // thereafter.
1056 // auto action = Return(std::initializer_list<std::string>{
1057 // "taco", "burrito",
1058 // });
1059 //
1060 // EXPECT_CALL(mock, Call)
1061 // .WillOnce(action)
1062 // .WillOnce(action)
1063 // .WillRepeatedly(Return(std::vector<std::string>{}));
1064 //
1065 // EXPECT_THAT(mock.AsStdFunction()(),
1066 // ElementsAre("taco", "burrito"));
1067 // EXPECT_THAT(mock.AsStdFunction()(),
1068 // ElementsAre("taco", "burrito"));
1069 // EXPECT_THAT(mock.AsStdFunction()(), IsEmpty());
1070 // }
1071 //
1072 U value;
1073 };
1074
1075 const std::shared_ptr<State> state_;
1076 };
1077
1078 R value_;
1079};
1080
1081// A specialization of ReturnAction<R> when R is ByMoveWrapper<T> for some T.
1082//
1083// This version applies the type system-defeating hack of moving from T even in
1084// the const call operator, checking at runtime that it isn't called more than
1085// once, since the user has declared their intent to do so by using ByMove.
1086template <typename T>
1087class ReturnAction<ByMoveWrapper<T>> final {
1088 public:
1089 explicit ReturnAction(ByMoveWrapper<T> wrapper)
1090 : state_(new State(std::move(wrapper.payload))) {}
1091
1092 T operator()() const {
1093 GTEST_CHECK_(!state_->called)
1094 << "A ByMove() action must be performed at most once.";
1095
1096 state_->called = true;
1097 return std::move(state_->value);
1098 }
1099
1100 private:
1101 // We store our state on the heap so that we are copyable as required by
1102 // Action, despite the fact that we are stateful and T may not be copyable.
1103 struct State {
1104 explicit State(T&& value_in) : value(std::move(value_in)) {}
1105
1106 T value;
1107 bool called = false;
1108 };
1109
1110 const std::shared_ptr<State> state_;
1111};
1112
1113// Implements the ReturnNull() action.
1114class ReturnNullAction {
1115 public:
1116 // Allows ReturnNull() to be used in any pointer-returning function. In C++11
1117 // this is enforced by returning nullptr, and in non-C++11 by asserting a
1118 // pointer type on compile time.
1119 template <typename Result, typename ArgumentTuple>
1120 static Result Perform(const ArgumentTuple&) {
1121 return nullptr;
1122 }
1123};
1124
1125// Implements the Return() action.
1126class ReturnVoidAction {
1127 public:
1128 // Allows Return() to be used in any void-returning function.
1129 template <typename Result, typename ArgumentTuple>
1130 static void Perform(const ArgumentTuple&) {
1131 static_assert(std::is_void<Result>::value, "Result should be void.");
1132 }
1133};
1134
1135// Implements the polymorphic ReturnRef(x) action, which can be used
1136// in any function that returns a reference to the type of x,
1137// regardless of the argument types.
1138template <typename T>
1139class ReturnRefAction {
1140 public:
1141 // Constructs a ReturnRefAction object from the reference to be returned.
1142 explicit ReturnRefAction(T& ref) : ref_(ref) {} // NOLINT
1143
1144 // This template type conversion operator allows ReturnRef(x) to be
1145 // used in ANY function that returns a reference to x's type.
1146 template <typename F>
1147 operator Action<F>() const {
1148 typedef typename Function<F>::Result Result;
1149 // Asserts that the function return type is a reference. This
1150 // catches the user error of using ReturnRef(x) when Return(x)
1151 // should be used, and generates some helpful error message.
1152 static_assert(std::is_reference<Result>::value,
1153 "use Return instead of ReturnRef to return a value");
1154 return Action<F>(new Impl<F>(ref_));
1155 }
1156
1157 private:
1158 // Implements the ReturnRef(x) action for a particular function type F.
1159 template <typename F>
1160 class Impl : public ActionInterface<F> {
1161 public:
1162 typedef typename Function<F>::Result Result;
1163 typedef typename Function<F>::ArgumentTuple ArgumentTuple;
1164
1165 explicit Impl(T& ref) : ref_(ref) {} // NOLINT
1166
1167 Result Perform(const ArgumentTuple&) override { return ref_; }
1168
1169 private:
1170 T& ref_;
1171 };
1172
1173 T& ref_;
1174};
1175
1176// Implements the polymorphic ReturnRefOfCopy(x) action, which can be
1177// used in any function that returns a reference to the type of x,
1178// regardless of the argument types.
1179template <typename T>
1180class ReturnRefOfCopyAction {
1181 public:
1182 // Constructs a ReturnRefOfCopyAction object from the reference to
1183 // be returned.
1184 explicit ReturnRefOfCopyAction(const T& value) : value_(value) {} // NOLINT
1185
1186 // This template type conversion operator allows ReturnRefOfCopy(x) to be
1187 // used in ANY function that returns a reference to x's type.
1188 template <typename F>
1189 operator Action<F>() const {
1190 typedef typename Function<F>::Result Result;
1191 // Asserts that the function return type is a reference. This
1192 // catches the user error of using ReturnRefOfCopy(x) when Return(x)
1193 // should be used, and generates some helpful error message.
1194 static_assert(std::is_reference<Result>::value,
1195 "use Return instead of ReturnRefOfCopy to return a value");
1196 return Action<F>(new Impl<F>(value_));
1197 }
1198
1199 private:
1200 // Implements the ReturnRefOfCopy(x) action for a particular function type F.
1201 template <typename F>
1202 class Impl : public ActionInterface<F> {
1203 public:
1204 typedef typename Function<F>::Result Result;
1205 typedef typename Function<F>::ArgumentTuple ArgumentTuple;
1206
1207 explicit Impl(const T& value) : value_(value) {} // NOLINT
1208
1209 Result Perform(const ArgumentTuple&) override { return value_; }
1210
1211 private:
1212 T value_;
1213 };
1214
1215 const T value_;
1216};
1217
1218// Implements the polymorphic ReturnRoundRobin(v) action, which can be
1219// used in any function that returns the element_type of v.
1220template <typename T>
1221class ReturnRoundRobinAction {
1222 public:
1223 explicit ReturnRoundRobinAction(std::vector<T> values) {
1224 GTEST_CHECK_(!values.empty())
1225 << "ReturnRoundRobin requires at least one element.";
1226 state_->values = std::move(values);
1227 }
1228
1229 template <typename... Args>
1230 T operator()(Args&&...) const {
1231 return state_->Next();
1232 }
1233
1234 private:
1235 struct State {
1236 T Next() {
1237 T ret_val = values[i++];
1238 if (i == values.size()) i = 0;
1239 return ret_val;
1240 }
1241
1242 std::vector<T> values;
1243 size_t i = 0;
1244 };
1245 std::shared_ptr<State> state_ = std::make_shared<State>();
1246};
1247
1248// Implements the polymorphic DoDefault() action.
1249class DoDefaultAction {
1250 public:
1251 // This template type conversion operator allows DoDefault() to be
1252 // used in any function.
1253 template <typename F>
1254 operator Action<F>() const {
1255 return Action<F>();
1256 } // NOLINT
1257};
1258
1259// Implements the Assign action to set a given pointer referent to a
1260// particular value.
1261template <typename T1, typename T2>
1262class AssignAction {
1263 public:
1264 AssignAction(T1* ptr, T2 value) : ptr_(ptr), value_(value) {}
1265
1266 template <typename Result, typename ArgumentTuple>
1267 void Perform(const ArgumentTuple& /* args */) const {
1268 *ptr_ = value_;
1269 }
1270
1271 private:
1272 T1* const ptr_;
1273 const T2 value_;
1274};
1275
1276#ifndef GTEST_OS_WINDOWS_MOBILE
1277
1278// Implements the SetErrnoAndReturn action to simulate return from
1279// various system calls and libc functions.
1280template <typename T>
1281class SetErrnoAndReturnAction {
1282 public:
1283 SetErrnoAndReturnAction(int errno_value, T result)
1284 : errno_(errno_value), result_(result) {}
1285 template <typename Result, typename ArgumentTuple>
1286 Result Perform(const ArgumentTuple& /* args */) const {
1287 errno = errno_;
1288 return result_;
1289 }
1290
1291 private:
1292 const int errno_;
1293 const T result_;
1294};
1295
1296#endif // !GTEST_OS_WINDOWS_MOBILE
1297
1298// Implements the SetArgumentPointee<N>(x) action for any function
1299// whose N-th argument (0-based) is a pointer to x's type.
1300template <size_t N, typename A, typename = void>
1301struct SetArgumentPointeeAction {
1302 A value;
1303
1304 template <typename... Args>
1305 void operator()(const Args&... args) const {
1306 *::std::get<N>(std::tie(args...)) = value;
1307 }
1308};
1309
1310// Implements the Invoke(object_ptr, &Class::Method) action.
1311template <class Class, typename MethodPtr>
1312struct InvokeMethodAction {
1313 Class* const obj_ptr;
1314 const MethodPtr method_ptr;
1315
1316 template <typename... Args>
1317 auto operator()(Args&&... args) const
1318 -> decltype((obj_ptr->*method_ptr)(std::forward<Args>(args)...)) {
1319 return (obj_ptr->*method_ptr)(std::forward<Args>(args)...);
1320 }
1321};
1322
1323// Implements the InvokeWithoutArgs(f) action. The template argument
1324// FunctionImpl is the implementation type of f, which can be either a
1325// function pointer or a functor. InvokeWithoutArgs(f) can be used as an
1326// Action<F> as long as f's type is compatible with F.
1327template <typename FunctionImpl>
1328struct InvokeWithoutArgsAction {
1329 FunctionImpl function_impl;
1330
1331 // Allows InvokeWithoutArgs(f) to be used as any action whose type is
1332 // compatible with f.
1333 template <typename... Args>
1334 auto operator()(const Args&...) -> decltype(function_impl()) {
1335 return function_impl();
1336 }
1337};
1338
1339// Implements the InvokeWithoutArgs(object_ptr, &Class::Method) action.
1340template <class Class, typename MethodPtr>
1341struct InvokeMethodWithoutArgsAction {
1342 Class* const obj_ptr;
1343 const MethodPtr method_ptr;
1344
1345 using ReturnType =
1346 decltype((std::declval<Class*>()->*std::declval<MethodPtr>())());
1347
1348 template <typename... Args>
1349 ReturnType operator()(const Args&...) const {
1350 return (obj_ptr->*method_ptr)();
1351 }
1352};
1353
1354// Implements the IgnoreResult(action) action.
1355template <typename A>
1356class IgnoreResultAction {
1357 public:
1358 explicit IgnoreResultAction(const A& action) : action_(action) {}
1359
1360 template <typename F>
1361 operator Action<F>() const {
1362 // Assert statement belongs here because this is the best place to verify
1363 // conditions on F. It produces the clearest error messages
1364 // in most compilers.
1365 // Impl really belongs in this scope as a local class but can't
1366 // because MSVC produces duplicate symbols in different translation units
1367 // in this case. Until MS fixes that bug we put Impl into the class scope
1368 // and put the typedef both here (for use in assert statement) and
1369 // in the Impl class. But both definitions must be the same.
1370 typedef typename internal::Function<F>::Result Result;
1371
1372 // Asserts at compile time that F returns void.
1373 static_assert(std::is_void<Result>::value, "Result type should be void.");
1374
1375 return Action<F>(new Impl<F>(action_));
1376 }
1377
1378 private:
1379 template <typename F>
1380 class Impl : public ActionInterface<F> {
1381 public:
1382 typedef typename internal::Function<F>::Result Result;
1383 typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
1384
1385 explicit Impl(const A& action) : action_(action) {}
1386
1387 void Perform(const ArgumentTuple& args) override {
1388 // Performs the action and ignores its result.
1389 action_.Perform(args);
1390 }
1391
1392 private:
1393 // Type OriginalFunction is the same as F except that its return
1394 // type is IgnoredValue.
1395 typedef
1396 typename internal::Function<F>::MakeResultIgnoredValue OriginalFunction;
1397
1398 const Action<OriginalFunction> action_;
1399 };
1400
1401 const A action_;
1402};
1403
1404template <typename InnerAction, size_t... I>
1405struct WithArgsAction {
1406 InnerAction inner_action;
1407
1408 // The signature of the function as seen by the inner action, given an out
1409 // action with the given result and argument types.
1410 template <typename R, typename... Args>
1411 using InnerSignature =
1412 R(typename std::tuple_element<I, std::tuple<Args...>>::type...);
1413
1414 // Rather than a call operator, we must define conversion operators to
1415 // particular action types. This is necessary for embedded actions like
1416 // DoDefault(), which rely on an action conversion operators rather than
1417 // providing a call operator because even with a particular set of arguments
1418 // they don't have a fixed return type.
1419
1420 template <
1421 typename R, typename... Args,
1422 typename std::enable_if<
1423 std::is_convertible<InnerAction,
1424 // Unfortunately we can't use the InnerSignature
1425 // alias here; MSVC complains about the I
1426 // parameter pack not being expanded (error C3520)
1427 // despite it being expanded in the type alias.
1428 // TupleElement is also an MSVC workaround.
1429 // See its definition for details.
1430 OnceAction<R(internal::TupleElement<
1431 I, std::tuple<Args...>>...)>>::value,
1432 int>::type = 0>
1433 operator OnceAction<R(Args...)>() && { // NOLINT
1434 struct OA {
1435 OnceAction<InnerSignature<R, Args...>> inner_action;
1436
1437 R operator()(Args&&... args) && {
1438 return std::move(inner_action)
1439 .Call(std::get<I>(
1440 std::forward_as_tuple(std::forward<Args>(args)...))...);
1441 }
1442 };
1443
1444 return OA{std::move(inner_action)};
1445 }
1446
1447 template <
1448 typename R, typename... Args,
1449 typename std::enable_if<
1450 std::is_convertible<const InnerAction&,
1451 // Unfortunately we can't use the InnerSignature
1452 // alias here; MSVC complains about the I
1453 // parameter pack not being expanded (error C3520)
1454 // despite it being expanded in the type alias.
1455 // TupleElement is also an MSVC workaround.
1456 // See its definition for details.
1457 Action<R(internal::TupleElement<
1458 I, std::tuple<Args...>>...)>>::value,
1459 int>::type = 0>
1460 operator Action<R(Args...)>() const { // NOLINT
1461 Action<InnerSignature<R, Args...>> converted(inner_action);
1462
1463 return [converted](Args&&... args) -> R {
1464 return converted.Perform(std::forward_as_tuple(
1465 std::get<I>(std::forward_as_tuple(std::forward<Args>(args)...))...));
1466 };
1467 }
1468};
1469
1470template <typename... Actions>
1471class DoAllAction;
1472
1473// Base case: only a single action.
1474template <typename FinalAction>
1475class DoAllAction<FinalAction> {
1476 public:
1477 struct UserConstructorTag {};
1478
1479 template <typename T>
1480 explicit DoAllAction(UserConstructorTag, T&& action)
1481 : final_action_(std::forward<T>(action)) {}
1482
1483 // Rather than a call operator, we must define conversion operators to
1484 // particular action types. This is necessary for embedded actions like
1485 // DoDefault(), which rely on an action conversion operators rather than
1486 // providing a call operator because even with a particular set of arguments
1487 // they don't have a fixed return type.
1488
1489 template <typename R, typename... Args,
1490 typename std::enable_if<
1491 std::is_convertible<FinalAction, OnceAction<R(Args...)>>::value,
1492 int>::type = 0>
1493 operator OnceAction<R(Args...)>() && { // NOLINT
1494 return std::move(final_action_);
1495 }
1496
1497 template <
1498 typename R, typename... Args,
1499 typename std::enable_if<
1500 std::is_convertible<const FinalAction&, Action<R(Args...)>>::value,
1501 int>::type = 0>
1502 operator Action<R(Args...)>() const { // NOLINT
1503 return final_action_;
1504 }
1505
1506 private:
1507 FinalAction final_action_;
1508};
1509
1510// Recursive case: support N actions by calling the initial action and then
1511// calling through to the base class containing N-1 actions.
1512template <typename InitialAction, typename... OtherActions>
1513class DoAllAction<InitialAction, OtherActions...>
1514 : private DoAllAction<OtherActions...> {
1515 private:
1516 using Base = DoAllAction<OtherActions...>;
1517
1518 // The type of reference that should be provided to an initial action for a
1519 // mocked function parameter of type T.
1520 //
1521 // There are two quirks here:
1522 //
1523 // * Unlike most forwarding functions, we pass scalars through by value.
1524 // This isn't strictly necessary because an lvalue reference would work
1525 // fine too and be consistent with other non-reference types, but it's
1526 // perhaps less surprising.
1527 //
1528 // For example if the mocked function has signature void(int), then it
1529 // might seem surprising for the user's initial action to need to be
1530 // convertible to Action<void(const int&)>. This is perhaps less
1531 // surprising for a non-scalar type where there may be a performance
1532 // impact, or it might even be impossible, to pass by value.
1533 //
1534 // * More surprisingly, `const T&` is often not a const reference type.
1535 // By the reference collapsing rules in C++17 [dcl.ref]/6, if T refers to
1536 // U& or U&& for some non-scalar type U, then InitialActionArgType<T> is
1537 // U&. In other words, we may hand over a non-const reference.
1538 //
1539 // So for example, given some non-scalar type Obj we have the following
1540 // mappings:
1541 //
1542 // T InitialActionArgType<T>
1543 // ------- -----------------------
1544 // Obj const Obj&
1545 // Obj& Obj&
1546 // Obj&& Obj&
1547 // const Obj const Obj&
1548 // const Obj& const Obj&
1549 // const Obj&& const Obj&
1550 //
1551 // In other words, the initial actions get a mutable view of an non-scalar
1552 // argument if and only if the mock function itself accepts a non-const
1553 // reference type. They are never given an rvalue reference to an
1554 // non-scalar type.
1555 //
1556 // This situation makes sense if you imagine use with a matcher that is
1557 // designed to write through a reference. For example, if the caller wants
1558 // to fill in a reference argument and then return a canned value:
1559 //
1560 // EXPECT_CALL(mock, Call)
1561 // .WillOnce(DoAll(SetArgReferee<0>(17), Return(19)));
1562 //
1563 template <typename T>
1564 using InitialActionArgType =
1565 typename std::conditional<std::is_scalar<T>::value, T, const T&>::type;
1566
1567 public:
1568 struct UserConstructorTag {};
1569
1570 template <typename T, typename... U>
1571 explicit DoAllAction(UserConstructorTag, T&& initial_action,
1572 U&&... other_actions)
1573 : Base({}, std::forward<U>(other_actions)...),
1574 initial_action_(std::forward<T>(initial_action)) {}
1575
1576 template <typename R, typename... Args,
1577 typename std::enable_if<
1578 conjunction<
1579 // Both the initial action and the rest must support
1580 // conversion to OnceAction.
1581 std::is_convertible<
1582 InitialAction,
1583 OnceAction<void(InitialActionArgType<Args>...)>>,
1584 std::is_convertible<Base, OnceAction<R(Args...)>>>::value,
1585 int>::type = 0>
1586 operator OnceAction<R(Args...)>() && { // NOLINT
1587 // Return an action that first calls the initial action with arguments
1588 // filtered through InitialActionArgType, then forwards arguments directly
1589 // to the base class to deal with the remaining actions.
1590 struct OA {
1591 OnceAction<void(InitialActionArgType<Args>...)> initial_action;
1592 OnceAction<R(Args...)> remaining_actions;
1593
1594 R operator()(Args... args) && {
1595 std::move(initial_action)
1596 .Call(static_cast<InitialActionArgType<Args>>(args)...);
1597
1598 return std::move(remaining_actions).Call(std::forward<Args>(args)...);
1599 }
1600 };
1601
1602 return OA{
1603 std::move(initial_action_),
1604 std::move(static_cast<Base&>(*this)),
1605 };
1606 }
1607
1608 template <
1609 typename R, typename... Args,
1610 typename std::enable_if<
1611 conjunction<
1612 // Both the initial action and the rest must support conversion to
1613 // Action.
1614 std::is_convertible<const InitialAction&,
1615 Action<void(InitialActionArgType<Args>...)>>,
1616 std::is_convertible<const Base&, Action<R(Args...)>>>::value,
1617 int>::type = 0>
1618 operator Action<R(Args...)>() const { // NOLINT
1619 // Return an action that first calls the initial action with arguments
1620 // filtered through InitialActionArgType, then forwards arguments directly
1621 // to the base class to deal with the remaining actions.
1622 struct OA {
1623 Action<void(InitialActionArgType<Args>...)> initial_action;
1624 Action<R(Args...)> remaining_actions;
1625
1626 R operator()(Args... args) const {
1627 initial_action.Perform(std::forward_as_tuple(
1628 static_cast<InitialActionArgType<Args>>(args)...));
1629
1630 return remaining_actions.Perform(
1631 std::forward_as_tuple(std::forward<Args>(args)...));
1632 }
1633 };
1634
1635 return OA{
1636 initial_action_,
1637 static_cast<const Base&>(*this),
1638 };
1639 }
1640
1641 private:
1642 InitialAction initial_action_;
1643};
1644
1645template <typename T, typename... Params>
1646struct ReturnNewAction {
1647 T* operator()() const {
1648 return internal::Apply(
1649 [](const Params&... unpacked_params) {
1650 return new T(unpacked_params...);
1651 },
1652 params);
1653 }
1654 std::tuple<Params...> params;
1655};
1656
1657template <size_t k>
1658struct ReturnArgAction {
1659 template <typename... Args,
1660 typename = typename std::enable_if<(k < sizeof...(Args))>::type>
1661 auto operator()(Args&&... args) const -> decltype(std::get<k>(
1662 std::forward_as_tuple(std::forward<Args>(args)...))) {
1663 return std::get<k>(std::forward_as_tuple(std::forward<Args>(args)...));
1664 }
1665};
1666
1667template <size_t k, typename Ptr>
1668struct SaveArgAction {
1669 Ptr pointer;
1670
1671 template <typename... Args>
1672 void operator()(const Args&... args) const {
1673 *pointer = std::get<k>(std::tie(args...));
1674 }
1675};
1676
1677template <size_t k, typename Ptr>
1678struct SaveArgPointeeAction {
1679 Ptr pointer;
1680
1681 template <typename... Args>
1682 void operator()(const Args&... args) const {
1683 *pointer = *std::get<k>(std::tie(args...));
1684 }
1685};
1686
1687template <size_t k, typename T>
1688struct SetArgRefereeAction {
1689 T value;
1690
1691 template <typename... Args>
1692 void operator()(Args&&... args) const {
1693 using argk_type =
1694 typename ::std::tuple_element<k, std::tuple<Args...>>::type;
1695 static_assert(std::is_lvalue_reference<argk_type>::value,
1696 "Argument must be a reference type.");
1697 std::get<k>(std::tie(args...)) = value;
1698 }
1699};
1700
1701template <size_t k, typename I1, typename I2>
1702struct SetArrayArgumentAction {
1703 I1 first;
1704 I2 last;
1705
1706 template <typename... Args>
1707 void operator()(const Args&... args) const {
1708 auto value = std::get<k>(std::tie(args...));
1709 for (auto it = first; it != last; ++it, (void)++value) {
1710 *value = *it;
1711 }
1712 }
1713};
1714
1715template <size_t k>
1716struct DeleteArgAction {
1717 template <typename... Args>
1718 void operator()(const Args&... args) const {
1719 delete std::get<k>(std::tie(args...));
1720 }
1721};
1722
1723template <typename Ptr>
1724struct ReturnPointeeAction {
1725 Ptr pointer;
1726 template <typename... Args>
1727 auto operator()(const Args&...) const -> decltype(*pointer) {
1728 return *pointer;
1729 }
1730};
1731
1732#if GTEST_HAS_EXCEPTIONS
1733template <typename T>
1734struct ThrowAction {
1735 T exception;
1736 // We use a conversion operator to adapt to any return type.
1737 template <typename R, typename... Args>
1738 operator Action<R(Args...)>() const { // NOLINT
1739 T copy = exception;
1740 return [copy](Args...) -> R { throw copy; };
1741 }
1742};
1743#endif // GTEST_HAS_EXCEPTIONS
1744
1745} // namespace internal
1746
1747// An Unused object can be implicitly constructed from ANY value.
1748// This is handy when defining actions that ignore some or all of the
1749// mock function arguments. For example, given
1750//
1751// MOCK_METHOD3(Foo, double(const string& label, double x, double y));
1752// MOCK_METHOD3(Bar, double(int index, double x, double y));
1753//
1754// instead of
1755//
1756// double DistanceToOriginWithLabel(const string& label, double x, double y) {
1757// return sqrt(x*x + y*y);
1758// }
1759// double DistanceToOriginWithIndex(int index, double x, double y) {
1760// return sqrt(x*x + y*y);
1761// }
1762// ...
1763// EXPECT_CALL(mock, Foo("abc", _, _))
1764// .WillOnce(Invoke(DistanceToOriginWithLabel));
1765// EXPECT_CALL(mock, Bar(5, _, _))
1766// .WillOnce(Invoke(DistanceToOriginWithIndex));
1767//
1768// you could write
1769//
1770// // We can declare any uninteresting argument as Unused.
1771// double DistanceToOrigin(Unused, double x, double y) {
1772// return sqrt(x*x + y*y);
1773// }
1774// ...
1775// EXPECT_CALL(mock, Foo("abc", _, _)).WillOnce(Invoke(DistanceToOrigin));
1776// EXPECT_CALL(mock, Bar(5, _, _)).WillOnce(Invoke(DistanceToOrigin));
1777typedef internal::IgnoredValue Unused;
1778
1779// Creates an action that does actions a1, a2, ..., sequentially in
1780// each invocation. All but the last action will have a readonly view of the
1781// arguments.
1782template <typename... Action>
1783internal::DoAllAction<typename std::decay<Action>::type...> DoAll(
1784 Action&&... action) {
1785 return internal::DoAllAction<typename std::decay<Action>::type...>(
1786 {}, std::forward<Action>(action)...);
1787}
1788
1789// WithArg<k>(an_action) creates an action that passes the k-th
1790// (0-based) argument of the mock function to an_action and performs
1791// it. It adapts an action accepting one argument to one that accepts
1792// multiple arguments. For convenience, we also provide
1793// WithArgs<k>(an_action) (defined below) as a synonym.
1794template <size_t k, typename InnerAction>
1795internal::WithArgsAction<typename std::decay<InnerAction>::type, k> WithArg(
1796 InnerAction&& action) {
1797 return {std::forward<InnerAction>(action)};
1798}
1799
1800// WithArgs<N1, N2, ..., Nk>(an_action) creates an action that passes
1801// the selected arguments of the mock function to an_action and
1802// performs it. It serves as an adaptor between actions with
1803// different argument lists.
1804template <size_t k, size_t... ks, typename InnerAction>
1805internal::WithArgsAction<typename std::decay<InnerAction>::type, k, ks...>
1806WithArgs(InnerAction&& action) {
1807 return {std::forward<InnerAction>(action)};
1808}
1809
1810// WithoutArgs(inner_action) can be used in a mock function with a
1811// non-empty argument list to perform inner_action, which takes no
1812// argument. In other words, it adapts an action accepting no
1813// argument to one that accepts (and ignores) arguments.
1814template <typename InnerAction>
1815internal::WithArgsAction<typename std::decay<InnerAction>::type> WithoutArgs(
1816 InnerAction&& action) {
1817 return {std::forward<InnerAction>(action)};
1818}
1819
1820// Creates an action that returns a value.
1821//
1822// The returned type can be used with a mock function returning a non-void,
1823// non-reference type U as follows:
1824//
1825// * If R is convertible to U and U is move-constructible, then the action can
1826// be used with WillOnce.
1827//
1828// * If const R& is convertible to U and U is copy-constructible, then the
1829// action can be used with both WillOnce and WillRepeatedly.
1830//
1831// The mock expectation contains the R value from which the U return value is
1832// constructed (a move/copy of the argument to Return). This means that the R
1833// value will survive at least until the mock object's expectations are cleared
1834// or the mock object is destroyed, meaning that U can safely be a
1835// reference-like type such as std::string_view:
1836//
1837// // The mock function returns a view of a copy of the string fed to
1838// // Return. The view is valid even after the action is performed.
1839// MockFunction<std::string_view()> mock;
1840// EXPECT_CALL(mock, Call).WillOnce(Return(std::string("taco")));
1841// const std::string_view result = mock.AsStdFunction()();
1842// EXPECT_EQ("taco", result);
1843//
1844template <typename R>
1845internal::ReturnAction<R> Return(R value) {
1846 return internal::ReturnAction<R>(std::move(value));
1847}
1848
1849// Creates an action that returns NULL.
1850inline PolymorphicAction<internal::ReturnNullAction> ReturnNull() {
1851 return MakePolymorphicAction(impl: internal::ReturnNullAction());
1852}
1853
1854// Creates an action that returns from a void function.
1855inline PolymorphicAction<internal::ReturnVoidAction> Return() {
1856 return MakePolymorphicAction(impl: internal::ReturnVoidAction());
1857}
1858
1859// Creates an action that returns the reference to a variable.
1860template <typename R>
1861inline internal::ReturnRefAction<R> ReturnRef(R& x) { // NOLINT
1862 return internal::ReturnRefAction<R>(x);
1863}
1864
1865// Prevent using ReturnRef on reference to temporary.
1866template <typename R, R* = nullptr>
1867internal::ReturnRefAction<R> ReturnRef(R&&) = delete;
1868
1869// Creates an action that returns the reference to a copy of the
1870// argument. The copy is created when the action is constructed and
1871// lives as long as the action.
1872template <typename R>
1873inline internal::ReturnRefOfCopyAction<R> ReturnRefOfCopy(const R& x) {
1874 return internal::ReturnRefOfCopyAction<R>(x);
1875}
1876
1877// DEPRECATED: use Return(x) directly with WillOnce.
1878//
1879// Modifies the parent action (a Return() action) to perform a move of the
1880// argument instead of a copy.
1881// Return(ByMove()) actions can only be executed once and will assert this
1882// invariant.
1883template <typename R>
1884internal::ByMoveWrapper<R> ByMove(R x) {
1885 return internal::ByMoveWrapper<R>(std::move(x));
1886}
1887
1888// Creates an action that returns an element of `vals`. Calling this action will
1889// repeatedly return the next value from `vals` until it reaches the end and
1890// will restart from the beginning.
1891template <typename T>
1892internal::ReturnRoundRobinAction<T> ReturnRoundRobin(std::vector<T> vals) {
1893 return internal::ReturnRoundRobinAction<T>(std::move(vals));
1894}
1895
1896// Creates an action that returns an element of `vals`. Calling this action will
1897// repeatedly return the next value from `vals` until it reaches the end and
1898// will restart from the beginning.
1899template <typename T>
1900internal::ReturnRoundRobinAction<T> ReturnRoundRobin(
1901 std::initializer_list<T> vals) {
1902 return internal::ReturnRoundRobinAction<T>(std::vector<T>(vals));
1903}
1904
1905// Creates an action that does the default action for the give mock function.
1906inline internal::DoDefaultAction DoDefault() {
1907 return internal::DoDefaultAction();
1908}
1909
1910// Creates an action that sets the variable pointed by the N-th
1911// (0-based) function argument to 'value'.
1912template <size_t N, typename T>
1913internal::SetArgumentPointeeAction<N, T> SetArgPointee(T value) {
1914 return {std::move(value)};
1915}
1916
1917// The following version is DEPRECATED.
1918template <size_t N, typename T>
1919internal::SetArgumentPointeeAction<N, T> SetArgumentPointee(T value) {
1920 return {std::move(value)};
1921}
1922
1923// Creates an action that sets a pointer referent to a given value.
1924template <typename T1, typename T2>
1925PolymorphicAction<internal::AssignAction<T1, T2>> Assign(T1* ptr, T2 val) {
1926 return MakePolymorphicAction(internal::AssignAction<T1, T2>(ptr, val));
1927}
1928
1929#ifndef GTEST_OS_WINDOWS_MOBILE
1930
1931// Creates an action that sets errno and returns the appropriate error.
1932template <typename T>
1933PolymorphicAction<internal::SetErrnoAndReturnAction<T>> SetErrnoAndReturn(
1934 int errval, T result) {
1935 return MakePolymorphicAction(
1936 internal::SetErrnoAndReturnAction<T>(errval, result));
1937}
1938
1939#endif // !GTEST_OS_WINDOWS_MOBILE
1940
1941// Various overloads for Invoke().
1942
1943// Legacy function.
1944// Actions can now be implicitly constructed from callables. No need to create
1945// wrapper objects.
1946// This function exists for backwards compatibility.
1947template <typename FunctionImpl>
1948typename std::decay<FunctionImpl>::type Invoke(FunctionImpl&& function_impl) {
1949 return std::forward<FunctionImpl>(function_impl);
1950}
1951
1952// Creates an action that invokes the given method on the given object
1953// with the mock function's arguments.
1954template <class Class, typename MethodPtr>
1955internal::InvokeMethodAction<Class, MethodPtr> Invoke(Class* obj_ptr,
1956 MethodPtr method_ptr) {
1957 return {obj_ptr, method_ptr};
1958}
1959
1960// Creates an action that invokes 'function_impl' with no argument.
1961template <typename FunctionImpl>
1962internal::InvokeWithoutArgsAction<typename std::decay<FunctionImpl>::type>
1963InvokeWithoutArgs(FunctionImpl function_impl) {
1964 return {std::move(function_impl)};
1965}
1966
1967// Creates an action that invokes the given method on the given object
1968// with no argument.
1969template <class Class, typename MethodPtr>
1970internal::InvokeMethodWithoutArgsAction<Class, MethodPtr> InvokeWithoutArgs(
1971 Class* obj_ptr, MethodPtr method_ptr) {
1972 return {obj_ptr, method_ptr};
1973}
1974
1975// Creates an action that performs an_action and throws away its
1976// result. In other words, it changes the return type of an_action to
1977// void. an_action MUST NOT return void, or the code won't compile.
1978template <typename A>
1979inline internal::IgnoreResultAction<A> IgnoreResult(const A& an_action) {
1980 return internal::IgnoreResultAction<A>(an_action);
1981}
1982
1983// Creates a reference wrapper for the given L-value. If necessary,
1984// you can explicitly specify the type of the reference. For example,
1985// suppose 'derived' is an object of type Derived, ByRef(derived)
1986// would wrap a Derived&. If you want to wrap a const Base& instead,
1987// where Base is a base class of Derived, just write:
1988//
1989// ByRef<const Base>(derived)
1990//
1991// N.B. ByRef is redundant with std::ref, std::cref and std::reference_wrapper.
1992// However, it may still be used for consistency with ByMove().
1993template <typename T>
1994inline ::std::reference_wrapper<T> ByRef(T& l_value) { // NOLINT
1995 return ::std::reference_wrapper<T>(l_value);
1996}
1997
1998// The ReturnNew<T>(a1, a2, ..., a_k) action returns a pointer to a new
1999// instance of type T, constructed on the heap with constructor arguments
2000// a1, a2, ..., and a_k. The caller assumes ownership of the returned value.
2001template <typename T, typename... Params>
2002internal::ReturnNewAction<T, typename std::decay<Params>::type...> ReturnNew(
2003 Params&&... params) {
2004 return {std::forward_as_tuple(std::forward<Params>(params)...)};
2005}
2006
2007// Action ReturnArg<k>() returns the k-th argument of the mock function.
2008template <size_t k>
2009internal::ReturnArgAction<k> ReturnArg() {
2010 return {};
2011}
2012
2013// Action SaveArg<k>(pointer) saves the k-th (0-based) argument of the
2014// mock function to *pointer.
2015template <size_t k, typename Ptr>
2016internal::SaveArgAction<k, Ptr> SaveArg(Ptr pointer) {
2017 return {pointer};
2018}
2019
2020// Action SaveArgPointee<k>(pointer) saves the value pointed to
2021// by the k-th (0-based) argument of the mock function to *pointer.
2022template <size_t k, typename Ptr>
2023internal::SaveArgPointeeAction<k, Ptr> SaveArgPointee(Ptr pointer) {
2024 return {pointer};
2025}
2026
2027// Action SetArgReferee<k>(value) assigns 'value' to the variable
2028// referenced by the k-th (0-based) argument of the mock function.
2029template <size_t k, typename T>
2030internal::SetArgRefereeAction<k, typename std::decay<T>::type> SetArgReferee(
2031 T&& value) {
2032 return {std::forward<T>(value)};
2033}
2034
2035// Action SetArrayArgument<k>(first, last) copies the elements in
2036// source range [first, last) to the array pointed to by the k-th
2037// (0-based) argument, which can be either a pointer or an
2038// iterator. The action does not take ownership of the elements in the
2039// source range.
2040template <size_t k, typename I1, typename I2>
2041internal::SetArrayArgumentAction<k, I1, I2> SetArrayArgument(I1 first,
2042 I2 last) {
2043 return {first, last};
2044}
2045
2046// Action DeleteArg<k>() deletes the k-th (0-based) argument of the mock
2047// function.
2048template <size_t k>
2049internal::DeleteArgAction<k> DeleteArg() {
2050 return {};
2051}
2052
2053// This action returns the value pointed to by 'pointer'.
2054template <typename Ptr>
2055internal::ReturnPointeeAction<Ptr> ReturnPointee(Ptr pointer) {
2056 return {pointer};
2057}
2058
2059// Action Throw(exception) can be used in a mock function of any type
2060// to throw the given exception. Any copyable value can be thrown.
2061#if GTEST_HAS_EXCEPTIONS
2062template <typename T>
2063internal::ThrowAction<typename std::decay<T>::type> Throw(T&& exception) {
2064 return {std::forward<T>(exception)};
2065}
2066#endif // GTEST_HAS_EXCEPTIONS
2067
2068namespace internal {
2069
2070// A macro from the ACTION* family (defined later in gmock-generated-actions.h)
2071// defines an action that can be used in a mock function. Typically,
2072// these actions only care about a subset of the arguments of the mock
2073// function. For example, if such an action only uses the second
2074// argument, it can be used in any mock function that takes >= 2
2075// arguments where the type of the second argument is compatible.
2076//
2077// Therefore, the action implementation must be prepared to take more
2078// arguments than it needs. The ExcessiveArg type is used to
2079// represent those excessive arguments. In order to keep the compiler
2080// error messages tractable, we define it in the testing namespace
2081// instead of testing::internal. However, this is an INTERNAL TYPE
2082// and subject to change without notice, so a user MUST NOT USE THIS
2083// TYPE DIRECTLY.
2084struct ExcessiveArg {};
2085
2086// Builds an implementation of an Action<> for some particular signature, using
2087// a class defined by an ACTION* macro.
2088template <typename F, typename Impl>
2089struct ActionImpl;
2090
2091template <typename Impl>
2092struct ImplBase {
2093 struct Holder {
2094 // Allows each copy of the Action<> to get to the Impl.
2095 explicit operator const Impl&() const { return *ptr; }
2096 std::shared_ptr<Impl> ptr;
2097 };
2098 using type = typename std::conditional<std::is_constructible<Impl>::value,
2099 Impl, Holder>::type;
2100};
2101
2102template <typename R, typename... Args, typename Impl>
2103struct ActionImpl<R(Args...), Impl> : ImplBase<Impl>::type {
2104 using Base = typename ImplBase<Impl>::type;
2105 using function_type = R(Args...);
2106 using args_type = std::tuple<Args...>;
2107
2108 ActionImpl() = default; // Only defined if appropriate for Base.
2109 explicit ActionImpl(std::shared_ptr<Impl> impl) : Base{std::move(impl)} {}
2110
2111 R operator()(Args&&... arg) const {
2112 static constexpr size_t kMaxArgs =
2113 sizeof...(Args) <= 10 ? sizeof...(Args) : 10;
2114 return Apply(MakeIndexSequence<kMaxArgs>{},
2115 MakeIndexSequence<10 - kMaxArgs>{},
2116 args_type{std::forward<Args>(arg)...});
2117 }
2118
2119 template <std::size_t... arg_id, std::size_t... excess_id>
2120 R Apply(IndexSequence<arg_id...>, IndexSequence<excess_id...>,
2121 const args_type& args) const {
2122 // Impl need not be specific to the signature of action being implemented;
2123 // only the implementing function body needs to have all of the specific
2124 // types instantiated. Up to 10 of the args that are provided by the
2125 // args_type get passed, followed by a dummy of unspecified type for the
2126 // remainder up to 10 explicit args.
2127 static constexpr ExcessiveArg kExcessArg{};
2128 return static_cast<const Impl&>(*this)
2129 .template gmock_PerformImpl<
2130 /*function_type=*/function_type, /*return_type=*/R,
2131 /*args_type=*/args_type,
2132 /*argN_type=*/
2133 typename std::tuple_element<arg_id, args_type>::type...>(
2134 /*args=*/args, std::get<arg_id>(args)...,
2135 ((void)excess_id, kExcessArg)...);
2136 }
2137};
2138
2139// Stores a default-constructed Impl as part of the Action<>'s
2140// std::function<>. The Impl should be trivial to copy.
2141template <typename F, typename Impl>
2142::testing::Action<F> MakeAction() {
2143 return ::testing::Action<F>(ActionImpl<F, Impl>());
2144}
2145
2146// Stores just the one given instance of Impl.
2147template <typename F, typename Impl>
2148::testing::Action<F> MakeAction(std::shared_ptr<Impl> impl) {
2149 return ::testing::Action<F>(ActionImpl<F, Impl>(std::move(impl)));
2150}
2151
2152#define GMOCK_INTERNAL_ARG_UNUSED(i, data, el) \
2153 , const arg##i##_type& arg##i GTEST_ATTRIBUTE_UNUSED_
2154#define GMOCK_ACTION_ARG_TYPES_AND_NAMES_UNUSED_ \
2155 const args_type& args GTEST_ATTRIBUTE_UNUSED_ GMOCK_PP_REPEAT( \
2156 GMOCK_INTERNAL_ARG_UNUSED, , 10)
2157
2158#define GMOCK_INTERNAL_ARG(i, data, el) , const arg##i##_type& arg##i
2159#define GMOCK_ACTION_ARG_TYPES_AND_NAMES_ \
2160 const args_type& args GMOCK_PP_REPEAT(GMOCK_INTERNAL_ARG, , 10)
2161
2162#define GMOCK_INTERNAL_TEMPLATE_ARG(i, data, el) , typename arg##i##_type
2163#define GMOCK_ACTION_TEMPLATE_ARGS_NAMES_ \
2164 GMOCK_PP_TAIL(GMOCK_PP_REPEAT(GMOCK_INTERNAL_TEMPLATE_ARG, , 10))
2165
2166#define GMOCK_INTERNAL_TYPENAME_PARAM(i, data, param) , typename param##_type
2167#define GMOCK_ACTION_TYPENAME_PARAMS_(params) \
2168 GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_TYPENAME_PARAM, , params))
2169
2170#define GMOCK_INTERNAL_TYPE_PARAM(i, data, param) , param##_type
2171#define GMOCK_ACTION_TYPE_PARAMS_(params) \
2172 GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_TYPE_PARAM, , params))
2173
2174#define GMOCK_INTERNAL_TYPE_GVALUE_PARAM(i, data, param) \
2175 , param##_type gmock_p##i
2176#define GMOCK_ACTION_TYPE_GVALUE_PARAMS_(params) \
2177 GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_TYPE_GVALUE_PARAM, , params))
2178
2179#define GMOCK_INTERNAL_GVALUE_PARAM(i, data, param) \
2180 , std::forward<param##_type>(gmock_p##i)
2181#define GMOCK_ACTION_GVALUE_PARAMS_(params) \
2182 GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_GVALUE_PARAM, , params))
2183
2184#define GMOCK_INTERNAL_INIT_PARAM(i, data, param) \
2185 , param(::std::forward<param##_type>(gmock_p##i))
2186#define GMOCK_ACTION_INIT_PARAMS_(params) \
2187 GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_INIT_PARAM, , params))
2188
2189#define GMOCK_INTERNAL_FIELD_PARAM(i, data, param) param##_type param;
2190#define GMOCK_ACTION_FIELD_PARAMS_(params) \
2191 GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_FIELD_PARAM, , params)
2192
2193#define GMOCK_INTERNAL_ACTION(name, full_name, params) \
2194 template <GMOCK_ACTION_TYPENAME_PARAMS_(params)> \
2195 class full_name { \
2196 public: \
2197 explicit full_name(GMOCK_ACTION_TYPE_GVALUE_PARAMS_(params)) \
2198 : impl_(std::make_shared<gmock_Impl>( \
2199 GMOCK_ACTION_GVALUE_PARAMS_(params))) {} \
2200 full_name(const full_name&) = default; \
2201 full_name(full_name&&) noexcept = default; \
2202 template <typename F> \
2203 operator ::testing::Action<F>() const { \
2204 return ::testing::internal::MakeAction<F>(impl_); \
2205 } \
2206 \
2207 private: \
2208 class gmock_Impl { \
2209 public: \
2210 explicit gmock_Impl(GMOCK_ACTION_TYPE_GVALUE_PARAMS_(params)) \
2211 : GMOCK_ACTION_INIT_PARAMS_(params) {} \
2212 template <typename function_type, typename return_type, \
2213 typename args_type, GMOCK_ACTION_TEMPLATE_ARGS_NAMES_> \
2214 return_type gmock_PerformImpl(GMOCK_ACTION_ARG_TYPES_AND_NAMES_) const; \
2215 GMOCK_ACTION_FIELD_PARAMS_(params) \
2216 }; \
2217 std::shared_ptr<const gmock_Impl> impl_; \
2218 }; \
2219 template <GMOCK_ACTION_TYPENAME_PARAMS_(params)> \
2220 inline full_name<GMOCK_ACTION_TYPE_PARAMS_(params)> name( \
2221 GMOCK_ACTION_TYPE_GVALUE_PARAMS_(params)) GTEST_MUST_USE_RESULT_; \
2222 template <GMOCK_ACTION_TYPENAME_PARAMS_(params)> \
2223 inline full_name<GMOCK_ACTION_TYPE_PARAMS_(params)> name( \
2224 GMOCK_ACTION_TYPE_GVALUE_PARAMS_(params)) { \
2225 return full_name<GMOCK_ACTION_TYPE_PARAMS_(params)>( \
2226 GMOCK_ACTION_GVALUE_PARAMS_(params)); \
2227 } \
2228 template <GMOCK_ACTION_TYPENAME_PARAMS_(params)> \
2229 template <typename function_type, typename return_type, typename args_type, \
2230 GMOCK_ACTION_TEMPLATE_ARGS_NAMES_> \
2231 return_type \
2232 full_name<GMOCK_ACTION_TYPE_PARAMS_(params)>::gmock_Impl::gmock_PerformImpl( \
2233 GMOCK_ACTION_ARG_TYPES_AND_NAMES_UNUSED_) const
2234
2235} // namespace internal
2236
2237// Similar to GMOCK_INTERNAL_ACTION, but no bound parameters are stored.
2238#define ACTION(name) \
2239 class name##Action { \
2240 public: \
2241 explicit name##Action() noexcept {} \
2242 name##Action(const name##Action&) noexcept {} \
2243 template <typename F> \
2244 operator ::testing::Action<F>() const { \
2245 return ::testing::internal::MakeAction<F, gmock_Impl>(); \
2246 } \
2247 \
2248 private: \
2249 class gmock_Impl { \
2250 public: \
2251 template <typename function_type, typename return_type, \
2252 typename args_type, GMOCK_ACTION_TEMPLATE_ARGS_NAMES_> \
2253 return_type gmock_PerformImpl(GMOCK_ACTION_ARG_TYPES_AND_NAMES_) const; \
2254 }; \
2255 }; \
2256 inline name##Action name() GTEST_MUST_USE_RESULT_; \
2257 inline name##Action name() { return name##Action(); } \
2258 template <typename function_type, typename return_type, typename args_type, \
2259 GMOCK_ACTION_TEMPLATE_ARGS_NAMES_> \
2260 return_type name##Action::gmock_Impl::gmock_PerformImpl( \
2261 GMOCK_ACTION_ARG_TYPES_AND_NAMES_UNUSED_) const
2262
2263#define ACTION_P(name, ...) \
2264 GMOCK_INTERNAL_ACTION(name, name##ActionP, (__VA_ARGS__))
2265
2266#define ACTION_P2(name, ...) \
2267 GMOCK_INTERNAL_ACTION(name, name##ActionP2, (__VA_ARGS__))
2268
2269#define ACTION_P3(name, ...) \
2270 GMOCK_INTERNAL_ACTION(name, name##ActionP3, (__VA_ARGS__))
2271
2272#define ACTION_P4(name, ...) \
2273 GMOCK_INTERNAL_ACTION(name, name##ActionP4, (__VA_ARGS__))
2274
2275#define ACTION_P5(name, ...) \
2276 GMOCK_INTERNAL_ACTION(name, name##ActionP5, (__VA_ARGS__))
2277
2278#define ACTION_P6(name, ...) \
2279 GMOCK_INTERNAL_ACTION(name, name##ActionP6, (__VA_ARGS__))
2280
2281#define ACTION_P7(name, ...) \
2282 GMOCK_INTERNAL_ACTION(name, name##ActionP7, (__VA_ARGS__))
2283
2284#define ACTION_P8(name, ...) \
2285 GMOCK_INTERNAL_ACTION(name, name##ActionP8, (__VA_ARGS__))
2286
2287#define ACTION_P9(name, ...) \
2288 GMOCK_INTERNAL_ACTION(name, name##ActionP9, (__VA_ARGS__))
2289
2290#define ACTION_P10(name, ...) \
2291 GMOCK_INTERNAL_ACTION(name, name##ActionP10, (__VA_ARGS__))
2292
2293} // namespace testing
2294
2295GTEST_DISABLE_MSC_WARNINGS_POP_() // 4100
2296
2297#endif // GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
2298