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29
30
31// Google Mock - a framework for writing C++ mock classes.
32//
33// This file implements some commonly used actions.
34
35// GOOGLETEST_CM0002 DO NOT DELETE
36
37#ifndef GMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
38#define GMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
39
40#ifndef _WIN32_WCE
41# include <errno.h>
42#endif
43
44#include <algorithm>
45#include <functional>
46#include <memory>
47#include <string>
48#include <type_traits>
49#include <utility>
50
51#include "gmock/internal/gmock-internal-utils.h"
52#include "gmock/internal/gmock-port.h"
53
54#ifdef _MSC_VER
55# pragma warning(push)
56# pragma warning(disable:4100)
57#endif
58
59namespace testing {
60
61// To implement an action Foo, define:
62// 1. a class FooAction that implements the ActionInterface interface, and
63// 2. a factory function that creates an Action object from a
64// const FooAction*.
65//
66// The two-level delegation design follows that of Matcher, providing
67// consistency for extension developers. It also eases ownership
68// management as Action objects can now be copied like plain values.
69
70namespace internal {
71
72// BuiltInDefaultValueGetter<T, true>::Get() returns a
73// default-constructed T value. BuiltInDefaultValueGetter<T,
74// false>::Get() crashes with an error.
75//
76// This primary template is used when kDefaultConstructible is true.
77template <typename T, bool kDefaultConstructible>
78struct BuiltInDefaultValueGetter {
79 static T Get() { return T(); }
80};
81template <typename T>
82struct BuiltInDefaultValueGetter<T, false> {
83 static T Get() {
84 Assert(false, __FILE__, __LINE__,
85 "Default action undefined for the function return type.");
86 return internal::Invalid<T>();
87 // The above statement will never be reached, but is required in
88 // order for this function to compile.
89 }
90};
91
92// BuiltInDefaultValue<T>::Get() returns the "built-in" default value
93// for type T, which is NULL when T is a raw pointer type, 0 when T is
94// a numeric type, false when T is bool, or "" when T is string or
95// std::string. In addition, in C++11 and above, it turns a
96// default-constructed T value if T is default constructible. For any
97// other type T, the built-in default T value is undefined, and the
98// function will abort the process.
99template <typename T>
100class BuiltInDefaultValue {
101 public:
102 // This function returns true if and only if type T has a built-in default
103 // value.
104 static bool Exists() {
105 return ::std::is_default_constructible<T>::value;
106 }
107
108 static T Get() {
109 return BuiltInDefaultValueGetter<
110 T, ::std::is_default_constructible<T>::value>::Get();
111 }
112};
113
114// This partial specialization says that we use the same built-in
115// default value for T and const T.
116template <typename T>
117class BuiltInDefaultValue<const T> {
118 public:
119 static bool Exists() { return BuiltInDefaultValue<T>::Exists(); }
120 static T Get() { return BuiltInDefaultValue<T>::Get(); }
121};
122
123// This partial specialization defines the default values for pointer
124// types.
125template <typename T>
126class BuiltInDefaultValue<T*> {
127 public:
128 static bool Exists() { return true; }
129 static T* Get() { return nullptr; }
130};
131
132// The following specializations define the default values for
133// specific types we care about.
134#define GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(type, value) \
135 template <> \
136 class BuiltInDefaultValue<type> { \
137 public: \
138 static bool Exists() { return true; } \
139 static type Get() { return value; } \
140 }
141
142GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(void, ); // NOLINT
143GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(::std::string, "");
144GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(bool, false);
145GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned char, '\0');
146GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed char, '\0');
147GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(char, '\0');
148
149// There's no need for a default action for signed wchar_t, as that
150// type is the same as wchar_t for gcc, and invalid for MSVC.
151//
152// There's also no need for a default action for unsigned wchar_t, as
153// that type is the same as unsigned int for gcc, and invalid for
154// MSVC.
155#if GMOCK_WCHAR_T_IS_NATIVE_
156GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(wchar_t, 0U); // NOLINT
157#endif
158
159GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned short, 0U); // NOLINT
160GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed short, 0); // NOLINT
161GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned int, 0U);
162GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed int, 0);
163GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned long, 0UL); // NOLINT
164GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed long, 0L); // NOLINT
165GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(UInt64, 0);
166GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(Int64, 0);
167GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(float, 0);
168GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(double, 0);
169
170#undef GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_
171
172} // namespace internal
173
174// When an unexpected function call is encountered, Google Mock will
175// let it return a default value if the user has specified one for its
176// return type, or if the return type has a built-in default value;
177// otherwise Google Mock won't know what value to return and will have
178// to abort the process.
179//
180// The DefaultValue<T> class allows a user to specify the
181// default value for a type T that is both copyable and publicly
182// destructible (i.e. anything that can be used as a function return
183// type). The usage is:
184//
185// // Sets the default value for type T to be foo.
186// DefaultValue<T>::Set(foo);
187template <typename T>
188class DefaultValue {
189 public:
190 // Sets the default value for type T; requires T to be
191 // copy-constructable and have a public destructor.
192 static void Set(T x) {
193 delete producer_;
194 producer_ = new FixedValueProducer(x);
195 }
196
197 // Provides a factory function to be called to generate the default value.
198 // This method can be used even if T is only move-constructible, but it is not
199 // limited to that case.
200 typedef T (*FactoryFunction)();
201 static void SetFactory(FactoryFunction factory) {
202 delete producer_;
203 producer_ = new FactoryValueProducer(factory);
204 }
205
206 // Unsets the default value for type T.
207 static void Clear() {
208 delete producer_;
209 producer_ = nullptr;
210 }
211
212 // Returns true if and only if the user has set the default value for type T.
213 static bool IsSet() { return producer_ != nullptr; }
214
215 // Returns true if T has a default return value set by the user or there
216 // exists a built-in default value.
217 static bool Exists() {
218 return IsSet() || internal::BuiltInDefaultValue<T>::Exists();
219 }
220
221 // Returns the default value for type T if the user has set one;
222 // otherwise returns the built-in default value. Requires that Exists()
223 // is true, which ensures that the return value is well-defined.
224 static T Get() {
225 return producer_ == nullptr ? internal::BuiltInDefaultValue<T>::Get()
226 : producer_->Produce();
227 }
228
229 private:
230 class ValueProducer {
231 public:
232 virtual ~ValueProducer() {}
233 virtual T Produce() = 0;
234 };
235
236 class FixedValueProducer : public ValueProducer {
237 public:
238 explicit FixedValueProducer(T value) : value_(value) {}
239 T Produce() override { return value_; }
240
241 private:
242 const T value_;
243 GTEST_DISALLOW_COPY_AND_ASSIGN_(FixedValueProducer);
244 };
245
246 class FactoryValueProducer : public ValueProducer {
247 public:
248 explicit FactoryValueProducer(FactoryFunction factory)
249 : factory_(factory) {}
250 T Produce() override { return factory_(); }
251
252 private:
253 const FactoryFunction factory_;
254 GTEST_DISALLOW_COPY_AND_ASSIGN_(FactoryValueProducer);
255 };
256
257 static ValueProducer* producer_;
258};
259
260// This partial specialization allows a user to set default values for
261// reference types.
262template <typename T>
263class DefaultValue<T&> {
264 public:
265 // Sets the default value for type T&.
266 static void Set(T& x) { // NOLINT
267 address_ = &x;
268 }
269
270 // Unsets the default value for type T&.
271 static void Clear() { address_ = nullptr; }
272
273 // Returns true if and only if the user has set the default value for type T&.
274 static bool IsSet() { return address_ != nullptr; }
275
276 // Returns true if T has a default return value set by the user or there
277 // exists a built-in default value.
278 static bool Exists() {
279 return IsSet() || internal::BuiltInDefaultValue<T&>::Exists();
280 }
281
282 // Returns the default value for type T& if the user has set one;
283 // otherwise returns the built-in default value if there is one;
284 // otherwise aborts the process.
285 static T& Get() {
286 return address_ == nullptr ? internal::BuiltInDefaultValue<T&>::Get()
287 : *address_;
288 }
289
290 private:
291 static T* address_;
292};
293
294// This specialization allows DefaultValue<void>::Get() to
295// compile.
296template <>
297class DefaultValue<void> {
298 public:
299 static bool Exists() { return true; }
300 static void Get() {}
301};
302
303// Points to the user-set default value for type T.
304template <typename T>
305typename DefaultValue<T>::ValueProducer* DefaultValue<T>::producer_ = nullptr;
306
307// Points to the user-set default value for type T&.
308template <typename T>
309T* DefaultValue<T&>::address_ = nullptr;
310
311// Implement this interface to define an action for function type F.
312template <typename F>
313class ActionInterface {
314 public:
315 typedef typename internal::Function<F>::Result Result;
316 typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
317
318 ActionInterface() {}
319 virtual ~ActionInterface() {}
320
321 // Performs the action. This method is not const, as in general an
322 // action can have side effects and be stateful. For example, a
323 // get-the-next-element-from-the-collection action will need to
324 // remember the current element.
325 virtual Result Perform(const ArgumentTuple& args) = 0;
326
327 private:
328 GTEST_DISALLOW_COPY_AND_ASSIGN_(ActionInterface);
329};
330
331// An Action<F> is a copyable and IMMUTABLE (except by assignment)
332// object that represents an action to be taken when a mock function
333// of type F is called. The implementation of Action<T> is just a
334// std::shared_ptr to const ActionInterface<T>. Don't inherit from Action!
335// You can view an object implementing ActionInterface<F> as a
336// concrete action (including its current state), and an Action<F>
337// object as a handle to it.
338template <typename F>
339class Action {
340 // Adapter class to allow constructing Action from a legacy ActionInterface.
341 // New code should create Actions from functors instead.
342 struct ActionAdapter {
343 // Adapter must be copyable to satisfy std::function requirements.
344 ::std::shared_ptr<ActionInterface<F>> impl_;
345
346 template <typename... Args>
347 typename internal::Function<F>::Result operator()(Args&&... args) {
348 return impl_->Perform(
349 ::std::forward_as_tuple(::std::forward<Args>(args)...));
350 }
351 };
352
353 public:
354 typedef typename internal::Function<F>::Result Result;
355 typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
356
357 // Constructs a null Action. Needed for storing Action objects in
358 // STL containers.
359 Action() {}
360
361 // Construct an Action from a specified callable.
362 // This cannot take std::function directly, because then Action would not be
363 // directly constructible from lambda (it would require two conversions).
364 template <typename G,
365 typename = typename ::std::enable_if<
366 ::std::is_constructible<::std::function<F>, G>::value>::type>
367 Action(G&& fun) : fun_(::std::forward<G>(fun)) {} // NOLINT
368
369 // Constructs an Action from its implementation.
370 explicit Action(ActionInterface<F>* impl)
371 : fun_(ActionAdapter{::std::shared_ptr<ActionInterface<F>>(impl)}) {}
372
373 // This constructor allows us to turn an Action<Func> object into an
374 // Action<F>, as long as F's arguments can be implicitly converted
375 // to Func's and Func's return type can be implicitly converted to F's.
376 template <typename Func>
377 explicit Action(const Action<Func>& action) : fun_(action.fun_) {}
378
379 // Returns true if and only if this is the DoDefault() action.
380 bool IsDoDefault() const { return fun_ == nullptr; }
381
382 // Performs the action. Note that this method is const even though
383 // the corresponding method in ActionInterface is not. The reason
384 // is that a const Action<F> means that it cannot be re-bound to
385 // another concrete action, not that the concrete action it binds to
386 // cannot change state. (Think of the difference between a const
387 // pointer and a pointer to const.)
388 Result Perform(ArgumentTuple args) const {
389 if (IsDoDefault()) {
390 internal::IllegalDoDefault(__FILE__, __LINE__);
391 }
392 return internal::Apply(fun_, ::std::move(args));
393 }
394
395 private:
396 template <typename G>
397 friend class Action;
398
399 // fun_ is an empty function if and only if this is the DoDefault() action.
400 ::std::function<F> fun_;
401};
402
403// The PolymorphicAction class template makes it easy to implement a
404// polymorphic action (i.e. an action that can be used in mock
405// functions of than one type, e.g. Return()).
406//
407// To define a polymorphic action, a user first provides a COPYABLE
408// implementation class that has a Perform() method template:
409//
410// class FooAction {
411// public:
412// template <typename Result, typename ArgumentTuple>
413// Result Perform(const ArgumentTuple& args) const {
414// // Processes the arguments and returns a result, using
415// // std::get<N>(args) to get the N-th (0-based) argument in the tuple.
416// }
417// ...
418// };
419//
420// Then the user creates the polymorphic action using
421// MakePolymorphicAction(object) where object has type FooAction. See
422// the definition of Return(void) and SetArgumentPointee<N>(value) for
423// complete examples.
424template <typename Impl>
425class PolymorphicAction {
426 public:
427 explicit PolymorphicAction(const Impl& impl) : impl_(impl) {}
428
429 template <typename F>
430 operator Action<F>() const {
431 return Action<F>(new MonomorphicImpl<F>(impl_));
432 }
433
434 private:
435 template <typename F>
436 class MonomorphicImpl : public ActionInterface<F> {
437 public:
438 typedef typename internal::Function<F>::Result Result;
439 typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
440
441 explicit MonomorphicImpl(const Impl& impl) : impl_(impl) {}
442
443 Result Perform(const ArgumentTuple& args) override {
444 return impl_.template Perform<Result>(args);
445 }
446
447 private:
448 Impl impl_;
449
450 GTEST_DISALLOW_ASSIGN_(MonomorphicImpl);
451 };
452
453 Impl impl_;
454
455 GTEST_DISALLOW_ASSIGN_(PolymorphicAction);
456};
457
458// Creates an Action from its implementation and returns it. The
459// created Action object owns the implementation.
460template <typename F>
461Action<F> MakeAction(ActionInterface<F>* impl) {
462 return Action<F>(impl);
463}
464
465// Creates a polymorphic action from its implementation. This is
466// easier to use than the PolymorphicAction<Impl> constructor as it
467// doesn't require you to explicitly write the template argument, e.g.
468//
469// MakePolymorphicAction(foo);
470// vs
471// PolymorphicAction<TypeOfFoo>(foo);
472template <typename Impl>
473inline PolymorphicAction<Impl> MakePolymorphicAction(const Impl& impl) {
474 return PolymorphicAction<Impl>(impl);
475}
476
477namespace internal {
478
479// Helper struct to specialize ReturnAction to execute a move instead of a copy
480// on return. Useful for move-only types, but could be used on any type.
481template <typename T>
482struct ByMoveWrapper {
483 explicit ByMoveWrapper(T value) : payload(std::move(value)) {}
484 T payload;
485};
486
487// Implements the polymorphic Return(x) action, which can be used in
488// any function that returns the type of x, regardless of the argument
489// types.
490//
491// Note: The value passed into Return must be converted into
492// Function<F>::Result when this action is cast to Action<F> rather than
493// when that action is performed. This is important in scenarios like
494//
495// MOCK_METHOD1(Method, T(U));
496// ...
497// {
498// Foo foo;
499// X x(&foo);
500// EXPECT_CALL(mock, Method(_)).WillOnce(Return(x));
501// }
502//
503// In the example above the variable x holds reference to foo which leaves
504// scope and gets destroyed. If copying X just copies a reference to foo,
505// that copy will be left with a hanging reference. If conversion to T
506// makes a copy of foo, the above code is safe. To support that scenario, we
507// need to make sure that the type conversion happens inside the EXPECT_CALL
508// statement, and conversion of the result of Return to Action<T(U)> is a
509// good place for that.
510//
511// The real life example of the above scenario happens when an invocation
512// of gtl::Container() is passed into Return.
513//
514template <typename R>
515class ReturnAction {
516 public:
517 // Constructs a ReturnAction object from the value to be returned.
518 // 'value' is passed by value instead of by const reference in order
519 // to allow Return("string literal") to compile.
520 explicit ReturnAction(R value) : value_(new R(std::move(value))) {}
521
522 // This template type conversion operator allows Return(x) to be
523 // used in ANY function that returns x's type.
524 template <typename F>
525 operator Action<F>() const { // NOLINT
526 // Assert statement belongs here because this is the best place to verify
527 // conditions on F. It produces the clearest error messages
528 // in most compilers.
529 // Impl really belongs in this scope as a local class but can't
530 // because MSVC produces duplicate symbols in different translation units
531 // in this case. Until MS fixes that bug we put Impl into the class scope
532 // and put the typedef both here (for use in assert statement) and
533 // in the Impl class. But both definitions must be the same.
534 typedef typename Function<F>::Result Result;
535 GTEST_COMPILE_ASSERT_(
536 !std::is_reference<Result>::value,
537 use_ReturnRef_instead_of_Return_to_return_a_reference);
538 static_assert(!std::is_void<Result>::value,
539 "Can't use Return() on an action expected to return `void`.");
540 return Action<F>(new Impl<R, F>(value_));
541 }
542
543 private:
544 // Implements the Return(x) action for a particular function type F.
545 template <typename R_, typename F>
546 class Impl : public ActionInterface<F> {
547 public:
548 typedef typename Function<F>::Result Result;
549 typedef typename Function<F>::ArgumentTuple ArgumentTuple;
550
551 // The implicit cast is necessary when Result has more than one
552 // single-argument constructor (e.g. Result is std::vector<int>) and R
553 // has a type conversion operator template. In that case, value_(value)
554 // won't compile as the compiler doesn't known which constructor of
555 // Result to call. ImplicitCast_ forces the compiler to convert R to
556 // Result without considering explicit constructors, thus resolving the
557 // ambiguity. value_ is then initialized using its copy constructor.
558 explicit Impl(const std::shared_ptr<R>& value)
559 : value_before_cast_(*value),
560 value_(ImplicitCast_<Result>(value_before_cast_)) {}
561
562 Result Perform(const ArgumentTuple&) override { return value_; }
563
564 private:
565 GTEST_COMPILE_ASSERT_(!std::is_reference<Result>::value,
566 Result_cannot_be_a_reference_type);
567 // We save the value before casting just in case it is being cast to a
568 // wrapper type.
569 R value_before_cast_;
570 Result value_;
571
572 GTEST_DISALLOW_COPY_AND_ASSIGN_(Impl);
573 };
574
575 // Partially specialize for ByMoveWrapper. This version of ReturnAction will
576 // move its contents instead.
577 template <typename R_, typename F>
578 class Impl<ByMoveWrapper<R_>, F> : public ActionInterface<F> {
579 public:
580 typedef typename Function<F>::Result Result;
581 typedef typename Function<F>::ArgumentTuple ArgumentTuple;
582
583 explicit Impl(const std::shared_ptr<R>& wrapper)
584 : performed_(false), wrapper_(wrapper) {}
585
586 Result Perform(const ArgumentTuple&) override {
587 GTEST_CHECK_(!performed_)
588 << "A ByMove() action should only be performed once.";
589 performed_ = true;
590 return std::move(wrapper_->payload);
591 }
592
593 private:
594 bool performed_;
595 const std::shared_ptr<R> wrapper_;
596
597 GTEST_DISALLOW_ASSIGN_(Impl);
598 };
599
600 const std::shared_ptr<R> value_;
601
602 GTEST_DISALLOW_ASSIGN_(ReturnAction);
603};
604
605// Implements the ReturnNull() action.
606class ReturnNullAction {
607 public:
608 // Allows ReturnNull() to be used in any pointer-returning function. In C++11
609 // this is enforced by returning nullptr, and in non-C++11 by asserting a
610 // pointer type on compile time.
611 template <typename Result, typename ArgumentTuple>
612 static Result Perform(const ArgumentTuple&) {
613 return nullptr;
614 }
615};
616
617// Implements the Return() action.
618class ReturnVoidAction {
619 public:
620 // Allows Return() to be used in any void-returning function.
621 template <typename Result, typename ArgumentTuple>
622 static void Perform(const ArgumentTuple&) {
623 static_assert(std::is_void<Result>::value, "Result should be void.");
624 }
625};
626
627// Implements the polymorphic ReturnRef(x) action, which can be used
628// in any function that returns a reference to the type of x,
629// regardless of the argument types.
630template <typename T>
631class ReturnRefAction {
632 public:
633 // Constructs a ReturnRefAction object from the reference to be returned.
634 explicit ReturnRefAction(T& ref) : ref_(ref) {} // NOLINT
635
636 // This template type conversion operator allows ReturnRef(x) to be
637 // used in ANY function that returns a reference to x's type.
638 template <typename F>
639 operator Action<F>() const {
640 typedef typename Function<F>::Result Result;
641 // Asserts that the function return type is a reference. This
642 // catches the user error of using ReturnRef(x) when Return(x)
643 // should be used, and generates some helpful error message.
644 GTEST_COMPILE_ASSERT_(std::is_reference<Result>::value,
645 use_Return_instead_of_ReturnRef_to_return_a_value);
646 return Action<F>(new Impl<F>(ref_));
647 }
648
649 private:
650 // Implements the ReturnRef(x) action for a particular function type F.
651 template <typename F>
652 class Impl : public ActionInterface<F> {
653 public:
654 typedef typename Function<F>::Result Result;
655 typedef typename Function<F>::ArgumentTuple ArgumentTuple;
656
657 explicit Impl(T& ref) : ref_(ref) {} // NOLINT
658
659 Result Perform(const ArgumentTuple&) override { return ref_; }
660
661 private:
662 T& ref_;
663
664 GTEST_DISALLOW_ASSIGN_(Impl);
665 };
666
667 T& ref_;
668
669 GTEST_DISALLOW_ASSIGN_(ReturnRefAction);
670};
671
672// Implements the polymorphic ReturnRefOfCopy(x) action, which can be
673// used in any function that returns a reference to the type of x,
674// regardless of the argument types.
675template <typename T>
676class ReturnRefOfCopyAction {
677 public:
678 // Constructs a ReturnRefOfCopyAction object from the reference to
679 // be returned.
680 explicit ReturnRefOfCopyAction(const T& value) : value_(value) {} // NOLINT
681
682 // This template type conversion operator allows ReturnRefOfCopy(x) to be
683 // used in ANY function that returns a reference to x's type.
684 template <typename F>
685 operator Action<F>() const {
686 typedef typename Function<F>::Result Result;
687 // Asserts that the function return type is a reference. This
688 // catches the user error of using ReturnRefOfCopy(x) when Return(x)
689 // should be used, and generates some helpful error message.
690 GTEST_COMPILE_ASSERT_(
691 std::is_reference<Result>::value,
692 use_Return_instead_of_ReturnRefOfCopy_to_return_a_value);
693 return Action<F>(new Impl<F>(value_));
694 }
695
696 private:
697 // Implements the ReturnRefOfCopy(x) action for a particular function type F.
698 template <typename F>
699 class Impl : public ActionInterface<F> {
700 public:
701 typedef typename Function<F>::Result Result;
702 typedef typename Function<F>::ArgumentTuple ArgumentTuple;
703
704 explicit Impl(const T& value) : value_(value) {} // NOLINT
705
706 Result Perform(const ArgumentTuple&) override { return value_; }
707
708 private:
709 T value_;
710
711 GTEST_DISALLOW_ASSIGN_(Impl);
712 };
713
714 const T value_;
715
716 GTEST_DISALLOW_ASSIGN_(ReturnRefOfCopyAction);
717};
718
719// Implements the polymorphic DoDefault() action.
720class DoDefaultAction {
721 public:
722 // This template type conversion operator allows DoDefault() to be
723 // used in any function.
724 template <typename F>
725 operator Action<F>() const { return Action<F>(); } // NOLINT
726};
727
728// Implements the Assign action to set a given pointer referent to a
729// particular value.
730template <typename T1, typename T2>
731class AssignAction {
732 public:
733 AssignAction(T1* ptr, T2 value) : ptr_(ptr), value_(value) {}
734
735 template <typename Result, typename ArgumentTuple>
736 void Perform(const ArgumentTuple& /* args */) const {
737 *ptr_ = value_;
738 }
739
740 private:
741 T1* const ptr_;
742 const T2 value_;
743
744 GTEST_DISALLOW_ASSIGN_(AssignAction);
745};
746
747#if !GTEST_OS_WINDOWS_MOBILE
748
749// Implements the SetErrnoAndReturn action to simulate return from
750// various system calls and libc functions.
751template <typename T>
752class SetErrnoAndReturnAction {
753 public:
754 SetErrnoAndReturnAction(int errno_value, T result)
755 : errno_(errno_value),
756 result_(result) {}
757 template <typename Result, typename ArgumentTuple>
758 Result Perform(const ArgumentTuple& /* args */) const {
759 errno = errno_;
760 return result_;
761 }
762
763 private:
764 const int errno_;
765 const T result_;
766
767 GTEST_DISALLOW_ASSIGN_(SetErrnoAndReturnAction);
768};
769
770#endif // !GTEST_OS_WINDOWS_MOBILE
771
772// Implements the SetArgumentPointee<N>(x) action for any function
773// whose N-th argument (0-based) is a pointer to x's type.
774template <size_t N, typename A, typename = void>
775struct SetArgumentPointeeAction {
776 A value;
777
778 template <typename... Args>
779 void operator()(const Args&... args) const {
780 *::std::get<N>(std::tie(args...)) = value;
781 }
782};
783
784// Implements the Invoke(object_ptr, &Class::Method) action.
785template <class Class, typename MethodPtr>
786struct InvokeMethodAction {
787 Class* const obj_ptr;
788 const MethodPtr method_ptr;
789
790 template <typename... Args>
791 auto operator()(Args&&... args) const
792 -> decltype((obj_ptr->*method_ptr)(std::forward<Args>(args)...)) {
793 return (obj_ptr->*method_ptr)(std::forward<Args>(args)...);
794 }
795};
796
797// Implements the InvokeWithoutArgs(f) action. The template argument
798// FunctionImpl is the implementation type of f, which can be either a
799// function pointer or a functor. InvokeWithoutArgs(f) can be used as an
800// Action<F> as long as f's type is compatible with F.
801template <typename FunctionImpl>
802struct InvokeWithoutArgsAction {
803 FunctionImpl function_impl;
804
805 // Allows InvokeWithoutArgs(f) to be used as any action whose type is
806 // compatible with f.
807 template <typename... Args>
808 auto operator()(const Args&...) -> decltype(function_impl()) {
809 return function_impl();
810 }
811};
812
813// Implements the InvokeWithoutArgs(object_ptr, &Class::Method) action.
814template <class Class, typename MethodPtr>
815struct InvokeMethodWithoutArgsAction {
816 Class* const obj_ptr;
817 const MethodPtr method_ptr;
818
819 using ReturnType = typename std::result_of<MethodPtr(Class*)>::type;
820
821 template <typename... Args>
822 ReturnType operator()(const Args&...) const {
823 return (obj_ptr->*method_ptr)();
824 }
825};
826
827// Implements the IgnoreResult(action) action.
828template <typename A>
829class IgnoreResultAction {
830 public:
831 explicit IgnoreResultAction(const A& action) : action_(action) {}
832
833 template <typename F>
834 operator Action<F>() const {
835 // Assert statement belongs here because this is the best place to verify
836 // conditions on F. It produces the clearest error messages
837 // in most compilers.
838 // Impl really belongs in this scope as a local class but can't
839 // because MSVC produces duplicate symbols in different translation units
840 // in this case. Until MS fixes that bug we put Impl into the class scope
841 // and put the typedef both here (for use in assert statement) and
842 // in the Impl class. But both definitions must be the same.
843 typedef typename internal::Function<F>::Result Result;
844
845 // Asserts at compile time that F returns void.
846 static_assert(std::is_void<Result>::value, "Result type should be void.");
847
848 return Action<F>(new Impl<F>(action_));
849 }
850
851 private:
852 template <typename F>
853 class Impl : public ActionInterface<F> {
854 public:
855 typedef typename internal::Function<F>::Result Result;
856 typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
857
858 explicit Impl(const A& action) : action_(action) {}
859
860 void Perform(const ArgumentTuple& args) override {
861 // Performs the action and ignores its result.
862 action_.Perform(args);
863 }
864
865 private:
866 // Type OriginalFunction is the same as F except that its return
867 // type is IgnoredValue.
868 typedef typename internal::Function<F>::MakeResultIgnoredValue
869 OriginalFunction;
870
871 const Action<OriginalFunction> action_;
872
873 GTEST_DISALLOW_ASSIGN_(Impl);
874 };
875
876 const A action_;
877
878 GTEST_DISALLOW_ASSIGN_(IgnoreResultAction);
879};
880
881template <typename InnerAction, size_t... I>
882struct WithArgsAction {
883 InnerAction action;
884
885 // The inner action could be anything convertible to Action<X>.
886 // We use the conversion operator to detect the signature of the inner Action.
887 template <typename R, typename... Args>
888 operator Action<R(Args...)>() const { // NOLINT
889 Action<R(typename std::tuple_element<I, std::tuple<Args...>>::type...)>
890 converted(action);
891
892 return [converted](Args... args) -> R {
893 return converted.Perform(std::forward_as_tuple(
894 std::get<I>(std::forward_as_tuple(std::forward<Args>(args)...))...));
895 };
896 }
897};
898
899template <typename... Actions>
900struct DoAllAction {
901 private:
902 template <typename... Args, size_t... I>
903 std::vector<Action<void(Args...)>> Convert(IndexSequence<I...>) const {
904 return {std::get<I>(actions)...};
905 }
906
907 public:
908 std::tuple<Actions...> actions;
909
910 template <typename R, typename... Args>
911 operator Action<R(Args...)>() const { // NOLINT
912 struct Op {
913 std::vector<Action<void(Args...)>> converted;
914 Action<R(Args...)> last;
915 R operator()(Args... args) const {
916 auto tuple_args = std::forward_as_tuple(std::forward<Args>(args)...);
917 for (auto& a : converted) {
918 a.Perform(tuple_args);
919 }
920 return last.Perform(tuple_args);
921 }
922 };
923 return Op{Convert<Args...>(MakeIndexSequence<sizeof...(Actions) - 1>()),
924 std::get<sizeof...(Actions) - 1>(actions)};
925 }
926};
927
928} // namespace internal
929
930// An Unused object can be implicitly constructed from ANY value.
931// This is handy when defining actions that ignore some or all of the
932// mock function arguments. For example, given
933//
934// MOCK_METHOD3(Foo, double(const string& label, double x, double y));
935// MOCK_METHOD3(Bar, double(int index, double x, double y));
936//
937// instead of
938//
939// double DistanceToOriginWithLabel(const string& label, double x, double y) {
940// return sqrt(x*x + y*y);
941// }
942// double DistanceToOriginWithIndex(int index, double x, double y) {
943// return sqrt(x*x + y*y);
944// }
945// ...
946// EXPECT_CALL(mock, Foo("abc", _, _))
947// .WillOnce(Invoke(DistanceToOriginWithLabel));
948// EXPECT_CALL(mock, Bar(5, _, _))
949// .WillOnce(Invoke(DistanceToOriginWithIndex));
950//
951// you could write
952//
953// // We can declare any uninteresting argument as Unused.
954// double DistanceToOrigin(Unused, double x, double y) {
955// return sqrt(x*x + y*y);
956// }
957// ...
958// EXPECT_CALL(mock, Foo("abc", _, _)).WillOnce(Invoke(DistanceToOrigin));
959// EXPECT_CALL(mock, Bar(5, _, _)).WillOnce(Invoke(DistanceToOrigin));
960typedef internal::IgnoredValue Unused;
961
962// Creates an action that does actions a1, a2, ..., sequentially in
963// each invocation.
964template <typename... Action>
965internal::DoAllAction<typename std::decay<Action>::type...> DoAll(
966 Action&&... action) {
967 return {std::forward_as_tuple(std::forward<Action>(action)...)};
968}
969
970// WithArg<k>(an_action) creates an action that passes the k-th
971// (0-based) argument of the mock function to an_action and performs
972// it. It adapts an action accepting one argument to one that accepts
973// multiple arguments. For convenience, we also provide
974// WithArgs<k>(an_action) (defined below) as a synonym.
975template <size_t k, typename InnerAction>
976internal::WithArgsAction<typename std::decay<InnerAction>::type, k>
977WithArg(InnerAction&& action) {
978 return {std::forward<InnerAction>(action)};
979}
980
981// WithArgs<N1, N2, ..., Nk>(an_action) creates an action that passes
982// the selected arguments of the mock function to an_action and
983// performs it. It serves as an adaptor between actions with
984// different argument lists.
985template <size_t k, size_t... ks, typename InnerAction>
986internal::WithArgsAction<typename std::decay<InnerAction>::type, k, ks...>
987WithArgs(InnerAction&& action) {
988 return {std::forward<InnerAction>(action)};
989}
990
991// WithoutArgs(inner_action) can be used in a mock function with a
992// non-empty argument list to perform inner_action, which takes no
993// argument. In other words, it adapts an action accepting no
994// argument to one that accepts (and ignores) arguments.
995template <typename InnerAction>
996internal::WithArgsAction<typename std::decay<InnerAction>::type>
997WithoutArgs(InnerAction&& action) {
998 return {std::forward<InnerAction>(action)};
999}
1000
1001// Creates an action that returns 'value'. 'value' is passed by value
1002// instead of const reference - otherwise Return("string literal")
1003// will trigger a compiler error about using array as initializer.
1004template <typename R>
1005internal::ReturnAction<R> Return(R value) {
1006 return internal::ReturnAction<R>(std::move(value));
1007}
1008
1009// Creates an action that returns NULL.
1010inline PolymorphicAction<internal::ReturnNullAction> ReturnNull() {
1011 return MakePolymorphicAction(internal::ReturnNullAction());
1012}
1013
1014// Creates an action that returns from a void function.
1015inline PolymorphicAction<internal::ReturnVoidAction> Return() {
1016 return MakePolymorphicAction(internal::ReturnVoidAction());
1017}
1018
1019// Creates an action that returns the reference to a variable.
1020template <typename R>
1021inline internal::ReturnRefAction<R> ReturnRef(R& x) { // NOLINT
1022 return internal::ReturnRefAction<R>(x);
1023}
1024
1025// Creates an action that returns the reference to a copy of the
1026// argument. The copy is created when the action is constructed and
1027// lives as long as the action.
1028template <typename R>
1029inline internal::ReturnRefOfCopyAction<R> ReturnRefOfCopy(const R& x) {
1030 return internal::ReturnRefOfCopyAction<R>(x);
1031}
1032
1033// Modifies the parent action (a Return() action) to perform a move of the
1034// argument instead of a copy.
1035// Return(ByMove()) actions can only be executed once and will assert this
1036// invariant.
1037template <typename R>
1038internal::ByMoveWrapper<R> ByMove(R x) {
1039 return internal::ByMoveWrapper<R>(std::move(x));
1040}
1041
1042// Creates an action that does the default action for the give mock function.
1043inline internal::DoDefaultAction DoDefault() {
1044 return internal::DoDefaultAction();
1045}
1046
1047// Creates an action that sets the variable pointed by the N-th
1048// (0-based) function argument to 'value'.
1049template <size_t N, typename T>
1050internal::SetArgumentPointeeAction<N, T> SetArgPointee(T x) {
1051 return {std::move(x)};
1052}
1053
1054// The following version is DEPRECATED.
1055template <size_t N, typename T>
1056internal::SetArgumentPointeeAction<N, T> SetArgumentPointee(T x) {
1057 return {std::move(x)};
1058}
1059
1060// Creates an action that sets a pointer referent to a given value.
1061template <typename T1, typename T2>
1062PolymorphicAction<internal::AssignAction<T1, T2> > Assign(T1* ptr, T2 val) {
1063 return MakePolymorphicAction(internal::AssignAction<T1, T2>(ptr, val));
1064}
1065
1066#if !GTEST_OS_WINDOWS_MOBILE
1067
1068// Creates an action that sets errno and returns the appropriate error.
1069template <typename T>
1070PolymorphicAction<internal::SetErrnoAndReturnAction<T> >
1071SetErrnoAndReturn(int errval, T result) {
1072 return MakePolymorphicAction(
1073 internal::SetErrnoAndReturnAction<T>(errval, result));
1074}
1075
1076#endif // !GTEST_OS_WINDOWS_MOBILE
1077
1078// Various overloads for Invoke().
1079
1080// Legacy function.
1081// Actions can now be implicitly constructed from callables. No need to create
1082// wrapper objects.
1083// This function exists for backwards compatibility.
1084template <typename FunctionImpl>
1085typename std::decay<FunctionImpl>::type Invoke(FunctionImpl&& function_impl) {
1086 return std::forward<FunctionImpl>(function_impl);
1087}
1088
1089// Creates an action that invokes the given method on the given object
1090// with the mock function's arguments.
1091template <class Class, typename MethodPtr>
1092internal::InvokeMethodAction<Class, MethodPtr> Invoke(Class* obj_ptr,
1093 MethodPtr method_ptr) {
1094 return {obj_ptr, method_ptr};
1095}
1096
1097// Creates an action that invokes 'function_impl' with no argument.
1098template <typename FunctionImpl>
1099internal::InvokeWithoutArgsAction<typename std::decay<FunctionImpl>::type>
1100InvokeWithoutArgs(FunctionImpl function_impl) {
1101 return {std::move(function_impl)};
1102}
1103
1104// Creates an action that invokes the given method on the given object
1105// with no argument.
1106template <class Class, typename MethodPtr>
1107internal::InvokeMethodWithoutArgsAction<Class, MethodPtr> InvokeWithoutArgs(
1108 Class* obj_ptr, MethodPtr method_ptr) {
1109 return {obj_ptr, method_ptr};
1110}
1111
1112// Creates an action that performs an_action and throws away its
1113// result. In other words, it changes the return type of an_action to
1114// void. an_action MUST NOT return void, or the code won't compile.
1115template <typename A>
1116inline internal::IgnoreResultAction<A> IgnoreResult(const A& an_action) {
1117 return internal::IgnoreResultAction<A>(an_action);
1118}
1119
1120// Creates a reference wrapper for the given L-value. If necessary,
1121// you can explicitly specify the type of the reference. For example,
1122// suppose 'derived' is an object of type Derived, ByRef(derived)
1123// would wrap a Derived&. If you want to wrap a const Base& instead,
1124// where Base is a base class of Derived, just write:
1125//
1126// ByRef<const Base>(derived)
1127//
1128// N.B. ByRef is redundant with std::ref, std::cref and std::reference_wrapper.
1129// However, it may still be used for consistency with ByMove().
1130template <typename T>
1131inline ::std::reference_wrapper<T> ByRef(T& l_value) { // NOLINT
1132 return ::std::reference_wrapper<T>(l_value);
1133}
1134
1135} // namespace testing
1136
1137#ifdef _MSC_VER
1138# pragma warning(pop)
1139#endif
1140
1141
1142#endif // GMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
1143