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30 // Author: wan@google.com (Zhanyong Wan)
31 
32 // Google Mock - a framework for writing C++ mock classes.
33 //
34 // This file implements some commonly used actions.
35 
36 #ifndef GMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
37 #define GMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
38 
39 #ifndef _WIN32_WCE
40 # include <errno.h>
41 #endif
42 
43 #include <algorithm>
44 #include <string>
45 
46 #include "gmock/internal/gmock-internal-utils.h"
47 #include "gmock/internal/gmock-port.h"
48 
49 namespace testing {
50 
51 // To implement an action Foo, define:
52 //   1. a class FooAction that implements the ActionInterface interface, and
53 //   2. a factory function that creates an Action object from a
54 //      const FooAction*.
55 //
56 // The two-level delegation design follows that of Matcher, providing
57 // consistency for extension developers.  It also eases ownership
58 // management as Action objects can now be copied like plain values.
59 
60 namespace internal {
61 
62 template <typename F1, typename F2>
63 class ActionAdaptor;
64 
65 // BuiltInDefaultValue<T>::Get() returns the "built-in" default
66 // value for type T, which is NULL when T is a pointer type, 0 when T
67 // is a numeric type, false when T is bool, or "" when T is string or
68 // std::string.  For any other type T, this value is undefined and the
69 // function will abort the process.
70 template <typename T>
71 class BuiltInDefaultValue {
72  public:
73   // This function returns true iff type T has a built-in default value.
Exists()74   static bool Exists() { return false; }
Get()75   static T Get() {
76     Assert(false, __FILE__, __LINE__,
77            "Default action undefined for the function return type.");
78     return internal::Invalid<T>();
79     // The above statement will never be reached, but is required in
80     // order for this function to compile.
81   }
82 };
83 
84 // This partial specialization says that we use the same built-in
85 // default value for T and const T.
86 template <typename T>
87 class BuiltInDefaultValue<const T> {
88  public:
Exists()89   static bool Exists() { return BuiltInDefaultValue<T>::Exists(); }
Get()90   static T Get() { return BuiltInDefaultValue<T>::Get(); }
91 };
92 
93 // This partial specialization defines the default values for pointer
94 // types.
95 template <typename T>
96 class BuiltInDefaultValue<T*> {
97  public:
Exists()98   static bool Exists() { return true; }
Get()99   static T* Get() { return NULL; }
100 };
101 
102 // The following specializations define the default values for
103 // specific types we care about.
104 #define GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(type, value) \
105   template <> \
106   class BuiltInDefaultValue<type> { \
107    public: \
108     static bool Exists() { return true; } \
109     static type Get() { return value; } \
110   }
111 
112 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(void, );  // NOLINT
113 #if GTEST_HAS_GLOBAL_STRING
114 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(::string, "");
115 #endif  // GTEST_HAS_GLOBAL_STRING
116 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(::std::string, "");
117 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(bool, false);
118 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned char, '\0');
119 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed char, '\0');
120 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(char, '\0');
121 
122 // There's no need for a default action for signed wchar_t, as that
123 // type is the same as wchar_t for gcc, and invalid for MSVC.
124 //
125 // There's also no need for a default action for unsigned wchar_t, as
126 // that type is the same as unsigned int for gcc, and invalid for
127 // MSVC.
128 #if GMOCK_WCHAR_T_IS_NATIVE_
129 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(wchar_t, 0U);  // NOLINT
130 #endif
131 
132 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned short, 0U);  // NOLINT
133 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed short, 0);     // NOLINT
134 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned int, 0U);
135 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed int, 0);
136 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned long, 0UL);  // NOLINT
137 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed long, 0L);     // NOLINT
138 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(UInt64, 0);
139 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(Int64, 0);
140 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(float, 0);
141 GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(double, 0);
142 
143 #undef GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_
144 
145 }  // namespace internal
146 
147 // When an unexpected function call is encountered, Google Mock will
148 // let it return a default value if the user has specified one for its
149 // return type, or if the return type has a built-in default value;
150 // otherwise Google Mock won't know what value to return and will have
151 // to abort the process.
152 //
153 // The DefaultValue<T> class allows a user to specify the
154 // default value for a type T that is both copyable and publicly
155 // destructible (i.e. anything that can be used as a function return
156 // type).  The usage is:
157 //
158 //   // Sets the default value for type T to be foo.
159 //   DefaultValue<T>::Set(foo);
160 template <typename T>
161 class DefaultValue {
162  public:
163   // Sets the default value for type T; requires T to be
164   // copy-constructable and have a public destructor.
Set(T x)165   static void Set(T x) {
166     delete value_;
167     value_ = new T(x);
168   }
169 
170   // Unsets the default value for type T.
Clear()171   static void Clear() {
172     delete value_;
173     value_ = NULL;
174   }
175 
176   // Returns true iff the user has set the default value for type T.
IsSet()177   static bool IsSet() { return value_ != NULL; }
178 
179   // Returns true if T has a default return value set by the user or there
180   // exists a built-in default value.
Exists()181   static bool Exists() {
182     return IsSet() || internal::BuiltInDefaultValue<T>::Exists();
183   }
184 
185   // Returns the default value for type T if the user has set one;
186   // otherwise returns the built-in default value if there is one;
187   // otherwise aborts the process.
Get()188   static T Get() {
189     return value_ == NULL ?
190         internal::BuiltInDefaultValue<T>::Get() : *value_;
191   }
192 
193  private:
194   static const T* value_;
195 };
196 
197 // This partial specialization allows a user to set default values for
198 // reference types.
199 template <typename T>
200 class DefaultValue<T&> {
201  public:
202   // Sets the default value for type T&.
Set(T & x)203   static void Set(T& x) {  // NOLINT
204     address_ = &x;
205   }
206 
207   // Unsets the default value for type T&.
Clear()208   static void Clear() {
209     address_ = NULL;
210   }
211 
212   // Returns true iff the user has set the default value for type T&.
IsSet()213   static bool IsSet() { return address_ != NULL; }
214 
215   // Returns true if T has a default return value set by the user or there
216   // exists a built-in default value.
Exists()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 if there is one;
223   // otherwise aborts the process.
Get()224   static T& Get() {
225     return address_ == NULL ?
226         internal::BuiltInDefaultValue<T&>::Get() : *address_;
227   }
228 
229  private:
230   static T* address_;
231 };
232 
233 // This specialization allows DefaultValue<void>::Get() to
234 // compile.
235 template <>
236 class DefaultValue<void> {
237  public:
Exists()238   static bool Exists() { return true; }
Get()239   static void Get() {}
240 };
241 
242 // Points to the user-set default value for type T.
243 template <typename T>
244 const T* DefaultValue<T>::value_ = NULL;
245 
246 // Points to the user-set default value for type T&.
247 template <typename T>
248 T* DefaultValue<T&>::address_ = NULL;
249 
250 // Implement this interface to define an action for function type F.
251 template <typename F>
252 class ActionInterface {
253  public:
254   typedef typename internal::Function<F>::Result Result;
255   typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
256 
ActionInterface()257   ActionInterface() {}
~ActionInterface()258   virtual ~ActionInterface() {}
259 
260   // Performs the action.  This method is not const, as in general an
261   // action can have side effects and be stateful.  For example, a
262   // get-the-next-element-from-the-collection action will need to
263   // remember the current element.
264   virtual Result Perform(const ArgumentTuple& args) = 0;
265 
266  private:
267   GTEST_DISALLOW_COPY_AND_ASSIGN_(ActionInterface);
268 };
269 
270 // An Action<F> is a copyable and IMMUTABLE (except by assignment)
271 // object that represents an action to be taken when a mock function
272 // of type F is called.  The implementation of Action<T> is just a
273 // linked_ptr to const ActionInterface<T>, so copying is fairly cheap.
274 // Don't inherit from Action!
275 //
276 // You can view an object implementing ActionInterface<F> as a
277 // concrete action (including its current state), and an Action<F>
278 // object as a handle to it.
279 template <typename F>
280 class Action {
281  public:
282   typedef typename internal::Function<F>::Result Result;
283   typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
284 
285   // Constructs a null Action.  Needed for storing Action objects in
286   // STL containers.
Action()287   Action() : impl_(NULL) {}
288 
289   // Constructs an Action from its implementation.  A NULL impl is
290   // used to represent the "do-default" action.
Action(ActionInterface<F> * impl)291   explicit Action(ActionInterface<F>* impl) : impl_(impl) {}
292 
293   // Copy constructor.
Action(const Action & action)294   Action(const Action& action) : impl_(action.impl_) {}
295 
296   // This constructor allows us to turn an Action<Func> object into an
297   // Action<F>, as long as F's arguments can be implicitly converted
298   // to Func's and Func's return type can be implicitly converted to
299   // F's.
300   template <typename Func>
301   explicit Action(const Action<Func>& action);
302 
303   // Returns true iff this is the DoDefault() action.
IsDoDefault()304   bool IsDoDefault() const { return impl_.get() == NULL; }
305 
306   // Performs the action.  Note that this method is const even though
307   // the corresponding method in ActionInterface is not.  The reason
308   // is that a const Action<F> means that it cannot be re-bound to
309   // another concrete action, not that the concrete action it binds to
310   // cannot change state.  (Think of the difference between a const
311   // pointer and a pointer to const.)
Perform(const ArgumentTuple & args)312   Result Perform(const ArgumentTuple& args) const {
313     internal::Assert(
314         !IsDoDefault(), __FILE__, __LINE__,
315         "You are using DoDefault() inside a composite action like "
316         "DoAll() or WithArgs().  This is not supported for technical "
317         "reasons.  Please instead spell out the default action, or "
318         "assign the default action to an Action variable and use "
319         "the variable in various places.");
320     return impl_->Perform(args);
321   }
322 
323  private:
324   template <typename F1, typename F2>
325   friend class internal::ActionAdaptor;
326 
327   internal::linked_ptr<ActionInterface<F> > impl_;
328 };
329 
330 // The PolymorphicAction class template makes it easy to implement a
331 // polymorphic action (i.e. an action that can be used in mock
332 // functions of than one type, e.g. Return()).
333 //
334 // To define a polymorphic action, a user first provides a COPYABLE
335 // implementation class that has a Perform() method template:
336 //
337 //   class FooAction {
338 //    public:
339 //     template <typename Result, typename ArgumentTuple>
340 //     Result Perform(const ArgumentTuple& args) const {
341 //       // Processes the arguments and returns a result, using
342 //       // tr1::get<N>(args) to get the N-th (0-based) argument in the tuple.
343 //     }
344 //     ...
345 //   };
346 //
347 // Then the user creates the polymorphic action using
348 // MakePolymorphicAction(object) where object has type FooAction.  See
349 // the definition of Return(void) and SetArgumentPointee<N>(value) for
350 // complete examples.
351 template <typename Impl>
352 class PolymorphicAction {
353  public:
PolymorphicAction(const Impl & impl)354   explicit PolymorphicAction(const Impl& impl) : impl_(impl) {}
355 
356   template <typename F>
357   operator Action<F>() const {
358     return Action<F>(new MonomorphicImpl<F>(impl_));
359   }
360 
361  private:
362   template <typename F>
363   class MonomorphicImpl : public ActionInterface<F> {
364    public:
365     typedef typename internal::Function<F>::Result Result;
366     typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
367 
MonomorphicImpl(const Impl & impl)368     explicit MonomorphicImpl(const Impl& impl) : impl_(impl) {}
369 
Perform(const ArgumentTuple & args)370     virtual Result Perform(const ArgumentTuple& args) {
371       return impl_.template Perform<Result>(args);
372     }
373 
374    private:
375     Impl impl_;
376 
377     GTEST_DISALLOW_ASSIGN_(MonomorphicImpl);
378   };
379 
380   Impl impl_;
381 
382   GTEST_DISALLOW_ASSIGN_(PolymorphicAction);
383 };
384 
385 // Creates an Action from its implementation and returns it.  The
386 // created Action object owns the implementation.
387 template <typename F>
MakeAction(ActionInterface<F> * impl)388 Action<F> MakeAction(ActionInterface<F>* impl) {
389   return Action<F>(impl);
390 }
391 
392 // Creates a polymorphic action from its implementation.  This is
393 // easier to use than the PolymorphicAction<Impl> constructor as it
394 // doesn't require you to explicitly write the template argument, e.g.
395 //
396 //   MakePolymorphicAction(foo);
397 // vs
398 //   PolymorphicAction<TypeOfFoo>(foo);
399 template <typename Impl>
MakePolymorphicAction(const Impl & impl)400 inline PolymorphicAction<Impl> MakePolymorphicAction(const Impl& impl) {
401   return PolymorphicAction<Impl>(impl);
402 }
403 
404 namespace internal {
405 
406 // Allows an Action<F2> object to pose as an Action<F1>, as long as F2
407 // and F1 are compatible.
408 template <typename F1, typename F2>
409 class ActionAdaptor : public ActionInterface<F1> {
410  public:
411   typedef typename internal::Function<F1>::Result Result;
412   typedef typename internal::Function<F1>::ArgumentTuple ArgumentTuple;
413 
ActionAdaptor(const Action<F2> & from)414   explicit ActionAdaptor(const Action<F2>& from) : impl_(from.impl_) {}
415 
Perform(const ArgumentTuple & args)416   virtual Result Perform(const ArgumentTuple& args) {
417     return impl_->Perform(args);
418   }
419 
420  private:
421   const internal::linked_ptr<ActionInterface<F2> > impl_;
422 
423   GTEST_DISALLOW_ASSIGN_(ActionAdaptor);
424 };
425 
426 // Implements the polymorphic Return(x) action, which can be used in
427 // any function that returns the type of x, regardless of the argument
428 // types.
429 //
430 // Note: The value passed into Return must be converted into
431 // Function<F>::Result when this action is cast to Action<F> rather than
432 // when that action is performed. This is important in scenarios like
433 //
434 // MOCK_METHOD1(Method, T(U));
435 // ...
436 // {
437 //   Foo foo;
438 //   X x(&foo);
439 //   EXPECT_CALL(mock, Method(_)).WillOnce(Return(x));
440 // }
441 //
442 // In the example above the variable x holds reference to foo which leaves
443 // scope and gets destroyed.  If copying X just copies a reference to foo,
444 // that copy will be left with a hanging reference.  If conversion to T
445 // makes a copy of foo, the above code is safe. To support that scenario, we
446 // need to make sure that the type conversion happens inside the EXPECT_CALL
447 // statement, and conversion of the result of Return to Action<T(U)> is a
448 // good place for that.
449 //
450 template <typename R>
451 class ReturnAction {
452  public:
453   // Constructs a ReturnAction object from the value to be returned.
454   // 'value' is passed by value instead of by const reference in order
455   // to allow Return("string literal") to compile.
ReturnAction(R value)456   explicit ReturnAction(R value) : value_(value) {}
457 
458   // This template type conversion operator allows Return(x) to be
459   // used in ANY function that returns x's type.
460   template <typename F>
461   operator Action<F>() const {
462     // Assert statement belongs here because this is the best place to verify
463     // conditions on F. It produces the clearest error messages
464     // in most compilers.
465     // Impl really belongs in this scope as a local class but can't
466     // because MSVC produces duplicate symbols in different translation units
467     // in this case. Until MS fixes that bug we put Impl into the class scope
468     // and put the typedef both here (for use in assert statement) and
469     // in the Impl class. But both definitions must be the same.
470     typedef typename Function<F>::Result Result;
471     GTEST_COMPILE_ASSERT_(
472         !internal::is_reference<Result>::value,
473         use_ReturnRef_instead_of_Return_to_return_a_reference);
474     return Action<F>(new Impl<F>(value_));
475   }
476 
477  private:
478   // Implements the Return(x) action for a particular function type F.
479   template <typename F>
480   class Impl : public ActionInterface<F> {
481    public:
482     typedef typename Function<F>::Result Result;
483     typedef typename Function<F>::ArgumentTuple ArgumentTuple;
484 
485     // The implicit cast is necessary when Result has more than one
486     // single-argument constructor (e.g. Result is std::vector<int>) and R
487     // has a type conversion operator template.  In that case, value_(value)
488     // won't compile as the compiler doesn't known which constructor of
489     // Result to call.  ImplicitCast_ forces the compiler to convert R to
490     // Result without considering explicit constructors, thus resolving the
491     // ambiguity. value_ is then initialized using its copy constructor.
Impl(R value)492     explicit Impl(R value)
493         : value_(::testing::internal::ImplicitCast_<Result>(value)) {}
494 
Perform(const ArgumentTuple &)495     virtual Result Perform(const ArgumentTuple&) { return value_; }
496 
497    private:
498     GTEST_COMPILE_ASSERT_(!internal::is_reference<Result>::value,
499                           Result_cannot_be_a_reference_type);
500     Result value_;
501 
502     GTEST_DISALLOW_ASSIGN_(Impl);
503   };
504 
505   R value_;
506 
507   GTEST_DISALLOW_ASSIGN_(ReturnAction);
508 };
509 
510 // Implements the ReturnNull() action.
511 class ReturnNullAction {
512  public:
513   // Allows ReturnNull() to be used in any pointer-returning function.
514   template <typename Result, typename ArgumentTuple>
Perform(const ArgumentTuple &)515   static Result Perform(const ArgumentTuple&) {
516     GTEST_COMPILE_ASSERT_(internal::is_pointer<Result>::value,
517                           ReturnNull_can_be_used_to_return_a_pointer_only);
518     return NULL;
519   }
520 };
521 
522 // Implements the Return() action.
523 class ReturnVoidAction {
524  public:
525   // Allows Return() to be used in any void-returning function.
526   template <typename Result, typename ArgumentTuple>
Perform(const ArgumentTuple &)527   static void Perform(const ArgumentTuple&) {
528     CompileAssertTypesEqual<void, Result>();
529   }
530 };
531 
532 // Implements the polymorphic ReturnRef(x) action, which can be used
533 // in any function that returns a reference to the type of x,
534 // regardless of the argument types.
535 template <typename T>
536 class ReturnRefAction {
537  public:
538   // Constructs a ReturnRefAction object from the reference to be returned.
ReturnRefAction(T & ref)539   explicit ReturnRefAction(T& ref) : ref_(ref) {}  // NOLINT
540 
541   // This template type conversion operator allows ReturnRef(x) to be
542   // used in ANY function that returns a reference to x's type.
543   template <typename F>
544   operator Action<F>() const {
545     typedef typename Function<F>::Result Result;
546     // Asserts that the function return type is a reference.  This
547     // catches the user error of using ReturnRef(x) when Return(x)
548     // should be used, and generates some helpful error message.
549     GTEST_COMPILE_ASSERT_(internal::is_reference<Result>::value,
550                           use_Return_instead_of_ReturnRef_to_return_a_value);
551     return Action<F>(new Impl<F>(ref_));
552   }
553 
554  private:
555   // Implements the ReturnRef(x) action for a particular function type F.
556   template <typename F>
557   class Impl : public ActionInterface<F> {
558    public:
559     typedef typename Function<F>::Result Result;
560     typedef typename Function<F>::ArgumentTuple ArgumentTuple;
561 
Impl(T & ref)562     explicit Impl(T& ref) : ref_(ref) {}  // NOLINT
563 
Perform(const ArgumentTuple &)564     virtual Result Perform(const ArgumentTuple&) {
565       return ref_;
566     }
567 
568    private:
569     T& ref_;
570 
571     GTEST_DISALLOW_ASSIGN_(Impl);
572   };
573 
574   T& ref_;
575 
576   GTEST_DISALLOW_ASSIGN_(ReturnRefAction);
577 };
578 
579 // Implements the polymorphic ReturnRefOfCopy(x) action, which can be
580 // used in any function that returns a reference to the type of x,
581 // regardless of the argument types.
582 template <typename T>
583 class ReturnRefOfCopyAction {
584  public:
585   // Constructs a ReturnRefOfCopyAction object from the reference to
586   // be returned.
ReturnRefOfCopyAction(const T & value)587   explicit ReturnRefOfCopyAction(const T& value) : value_(value) {}  // NOLINT
588 
589   // This template type conversion operator allows ReturnRefOfCopy(x) to be
590   // used in ANY function that returns a reference to x's type.
591   template <typename F>
592   operator Action<F>() const {
593     typedef typename Function<F>::Result Result;
594     // Asserts that the function return type is a reference.  This
595     // catches the user error of using ReturnRefOfCopy(x) when Return(x)
596     // should be used, and generates some helpful error message.
597     GTEST_COMPILE_ASSERT_(
598         internal::is_reference<Result>::value,
599         use_Return_instead_of_ReturnRefOfCopy_to_return_a_value);
600     return Action<F>(new Impl<F>(value_));
601   }
602 
603  private:
604   // Implements the ReturnRefOfCopy(x) action for a particular function type F.
605   template <typename F>
606   class Impl : public ActionInterface<F> {
607    public:
608     typedef typename Function<F>::Result Result;
609     typedef typename Function<F>::ArgumentTuple ArgumentTuple;
610 
Impl(const T & value)611     explicit Impl(const T& value) : value_(value) {}  // NOLINT
612 
Perform(const ArgumentTuple &)613     virtual Result Perform(const ArgumentTuple&) {
614       return value_;
615     }
616 
617    private:
618     T value_;
619 
620     GTEST_DISALLOW_ASSIGN_(Impl);
621   };
622 
623   const T value_;
624 
625   GTEST_DISALLOW_ASSIGN_(ReturnRefOfCopyAction);
626 };
627 
628 // Implements the polymorphic DoDefault() action.
629 class DoDefaultAction {
630  public:
631   // This template type conversion operator allows DoDefault() to be
632   // used in any function.
633   template <typename F>
634   operator Action<F>() const { return Action<F>(NULL); }
635 };
636 
637 // Implements the Assign action to set a given pointer referent to a
638 // particular value.
639 template <typename T1, typename T2>
640 class AssignAction {
641  public:
AssignAction(T1 * ptr,T2 value)642   AssignAction(T1* ptr, T2 value) : ptr_(ptr), value_(value) {}
643 
644   template <typename Result, typename ArgumentTuple>
Perform(const ArgumentTuple &)645   void Perform(const ArgumentTuple& /* args */) const {
646     *ptr_ = value_;
647   }
648 
649  private:
650   T1* const ptr_;
651   const T2 value_;
652 
653   GTEST_DISALLOW_ASSIGN_(AssignAction);
654 };
655 
656 #if !GTEST_OS_WINDOWS_MOBILE
657 
658 // Implements the SetErrnoAndReturn action to simulate return from
659 // various system calls and libc functions.
660 template <typename T>
661 class SetErrnoAndReturnAction {
662  public:
SetErrnoAndReturnAction(int errno_value,T result)663   SetErrnoAndReturnAction(int errno_value, T result)
664       : errno_(errno_value),
665         result_(result) {}
666   template <typename Result, typename ArgumentTuple>
Perform(const ArgumentTuple &)667   Result Perform(const ArgumentTuple& /* args */) const {
668     errno = errno_;
669     return result_;
670   }
671 
672  private:
673   const int errno_;
674   const T result_;
675 
676   GTEST_DISALLOW_ASSIGN_(SetErrnoAndReturnAction);
677 };
678 
679 #endif  // !GTEST_OS_WINDOWS_MOBILE
680 
681 // Implements the SetArgumentPointee<N>(x) action for any function
682 // whose N-th argument (0-based) is a pointer to x's type.  The
683 // template parameter kIsProto is true iff type A is ProtocolMessage,
684 // proto2::Message, or a sub-class of those.
685 template <size_t N, typename A, bool kIsProto>
686 class SetArgumentPointeeAction {
687  public:
688   // Constructs an action that sets the variable pointed to by the
689   // N-th function argument to 'value'.
SetArgumentPointeeAction(const A & value)690   explicit SetArgumentPointeeAction(const A& value) : value_(value) {}
691 
692   template <typename Result, typename ArgumentTuple>
Perform(const ArgumentTuple & args)693   void Perform(const ArgumentTuple& args) const {
694     CompileAssertTypesEqual<void, Result>();
695     *::std::tr1::get<N>(args) = value_;
696   }
697 
698  private:
699   const A value_;
700 
701   GTEST_DISALLOW_ASSIGN_(SetArgumentPointeeAction);
702 };
703 
704 template <size_t N, typename Proto>
705 class SetArgumentPointeeAction<N, Proto, true> {
706  public:
707   // Constructs an action that sets the variable pointed to by the
708   // N-th function argument to 'proto'.  Both ProtocolMessage and
709   // proto2::Message have the CopyFrom() method, so the same
710   // implementation works for both.
SetArgumentPointeeAction(const Proto & proto)711   explicit SetArgumentPointeeAction(const Proto& proto) : proto_(new Proto) {
712     proto_->CopyFrom(proto);
713   }
714 
715   template <typename Result, typename ArgumentTuple>
Perform(const ArgumentTuple & args)716   void Perform(const ArgumentTuple& args) const {
717     CompileAssertTypesEqual<void, Result>();
718     ::std::tr1::get<N>(args)->CopyFrom(*proto_);
719   }
720 
721  private:
722   const internal::linked_ptr<Proto> proto_;
723 
724   GTEST_DISALLOW_ASSIGN_(SetArgumentPointeeAction);
725 };
726 
727 // Implements the InvokeWithoutArgs(f) action.  The template argument
728 // FunctionImpl is the implementation type of f, which can be either a
729 // function pointer or a functor.  InvokeWithoutArgs(f) can be used as an
730 // Action<F> as long as f's type is compatible with F (i.e. f can be
731 // assigned to a tr1::function<F>).
732 template <typename FunctionImpl>
733 class InvokeWithoutArgsAction {
734  public:
735   // The c'tor makes a copy of function_impl (either a function
736   // pointer or a functor).
InvokeWithoutArgsAction(FunctionImpl function_impl)737   explicit InvokeWithoutArgsAction(FunctionImpl function_impl)
738       : function_impl_(function_impl) {}
739 
740   // Allows InvokeWithoutArgs(f) to be used as any action whose type is
741   // compatible with f.
742   template <typename Result, typename ArgumentTuple>
Perform(const ArgumentTuple &)743   Result Perform(const ArgumentTuple&) { return function_impl_(); }
744 
745  private:
746   FunctionImpl function_impl_;
747 
748   GTEST_DISALLOW_ASSIGN_(InvokeWithoutArgsAction);
749 };
750 
751 // Implements the InvokeWithoutArgs(object_ptr, &Class::Method) action.
752 template <class Class, typename MethodPtr>
753 class InvokeMethodWithoutArgsAction {
754  public:
InvokeMethodWithoutArgsAction(Class * obj_ptr,MethodPtr method_ptr)755   InvokeMethodWithoutArgsAction(Class* obj_ptr, MethodPtr method_ptr)
756       : obj_ptr_(obj_ptr), method_ptr_(method_ptr) {}
757 
758   template <typename Result, typename ArgumentTuple>
Perform(const ArgumentTuple &)759   Result Perform(const ArgumentTuple&) const {
760     return (obj_ptr_->*method_ptr_)();
761   }
762 
763  private:
764   Class* const obj_ptr_;
765   const MethodPtr method_ptr_;
766 
767   GTEST_DISALLOW_ASSIGN_(InvokeMethodWithoutArgsAction);
768 };
769 
770 // Implements the IgnoreResult(action) action.
771 template <typename A>
772 class IgnoreResultAction {
773  public:
IgnoreResultAction(const A & action)774   explicit IgnoreResultAction(const A& action) : action_(action) {}
775 
776   template <typename F>
777   operator Action<F>() const {
778     // Assert statement belongs here because this is the best place to verify
779     // conditions on F. It produces the clearest error messages
780     // in most compilers.
781     // Impl really belongs in this scope as a local class but can't
782     // because MSVC produces duplicate symbols in different translation units
783     // in this case. Until MS fixes that bug we put Impl into the class scope
784     // and put the typedef both here (for use in assert statement) and
785     // in the Impl class. But both definitions must be the same.
786     typedef typename internal::Function<F>::Result Result;
787 
788     // Asserts at compile time that F returns void.
789     CompileAssertTypesEqual<void, Result>();
790 
791     return Action<F>(new Impl<F>(action_));
792   }
793 
794  private:
795   template <typename F>
796   class Impl : public ActionInterface<F> {
797    public:
798     typedef typename internal::Function<F>::Result Result;
799     typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
800 
Impl(const A & action)801     explicit Impl(const A& action) : action_(action) {}
802 
Perform(const ArgumentTuple & args)803     virtual void Perform(const ArgumentTuple& args) {
804       // Performs the action and ignores its result.
805       action_.Perform(args);
806     }
807 
808    private:
809     // Type OriginalFunction is the same as F except that its return
810     // type is IgnoredValue.
811     typedef typename internal::Function<F>::MakeResultIgnoredValue
812         OriginalFunction;
813 
814     const Action<OriginalFunction> action_;
815 
816     GTEST_DISALLOW_ASSIGN_(Impl);
817   };
818 
819   const A action_;
820 
821   GTEST_DISALLOW_ASSIGN_(IgnoreResultAction);
822 };
823 
824 // A ReferenceWrapper<T> object represents a reference to type T,
825 // which can be either const or not.  It can be explicitly converted
826 // from, and implicitly converted to, a T&.  Unlike a reference,
827 // ReferenceWrapper<T> can be copied and can survive template type
828 // inference.  This is used to support by-reference arguments in the
829 // InvokeArgument<N>(...) action.  The idea was from "reference
830 // wrappers" in tr1, which we don't have in our source tree yet.
831 template <typename T>
832 class ReferenceWrapper {
833  public:
834   // Constructs a ReferenceWrapper<T> object from a T&.
ReferenceWrapper(T & l_value)835   explicit ReferenceWrapper(T& l_value) : pointer_(&l_value) {}  // NOLINT
836 
837   // Allows a ReferenceWrapper<T> object to be implicitly converted to
838   // a T&.
839   operator T&() const { return *pointer_; }
840  private:
841   T* pointer_;
842 };
843 
844 // Allows the expression ByRef(x) to be printed as a reference to x.
845 template <typename T>
PrintTo(const ReferenceWrapper<T> & ref,::std::ostream * os)846 void PrintTo(const ReferenceWrapper<T>& ref, ::std::ostream* os) {
847   T& value = ref;
848   UniversalPrinter<T&>::Print(value, os);
849 }
850 
851 // Does two actions sequentially.  Used for implementing the DoAll(a1,
852 // a2, ...) action.
853 template <typename Action1, typename Action2>
854 class DoBothAction {
855  public:
DoBothAction(Action1 action1,Action2 action2)856   DoBothAction(Action1 action1, Action2 action2)
857       : action1_(action1), action2_(action2) {}
858 
859   // This template type conversion operator allows DoAll(a1, ..., a_n)
860   // to be used in ANY function of compatible type.
861   template <typename F>
862   operator Action<F>() const {
863     return Action<F>(new Impl<F>(action1_, action2_));
864   }
865 
866  private:
867   // Implements the DoAll(...) action for a particular function type F.
868   template <typename F>
869   class Impl : public ActionInterface<F> {
870    public:
871     typedef typename Function<F>::Result Result;
872     typedef typename Function<F>::ArgumentTuple ArgumentTuple;
873     typedef typename Function<F>::MakeResultVoid VoidResult;
874 
Impl(const Action<VoidResult> & action1,const Action<F> & action2)875     Impl(const Action<VoidResult>& action1, const Action<F>& action2)
876         : action1_(action1), action2_(action2) {}
877 
Perform(const ArgumentTuple & args)878     virtual Result Perform(const ArgumentTuple& args) {
879       action1_.Perform(args);
880       return action2_.Perform(args);
881     }
882 
883    private:
884     const Action<VoidResult> action1_;
885     const Action<F> action2_;
886 
887     GTEST_DISALLOW_ASSIGN_(Impl);
888   };
889 
890   Action1 action1_;
891   Action2 action2_;
892 
893   GTEST_DISALLOW_ASSIGN_(DoBothAction);
894 };
895 
896 }  // namespace internal
897 
898 // An Unused object can be implicitly constructed from ANY value.
899 // This is handy when defining actions that ignore some or all of the
900 // mock function arguments.  For example, given
901 //
902 //   MOCK_METHOD3(Foo, double(const string& label, double x, double y));
903 //   MOCK_METHOD3(Bar, double(int index, double x, double y));
904 //
905 // instead of
906 //
907 //   double DistanceToOriginWithLabel(const string& label, double x, double y) {
908 //     return sqrt(x*x + y*y);
909 //   }
910 //   double DistanceToOriginWithIndex(int index, double x, double y) {
911 //     return sqrt(x*x + y*y);
912 //   }
913 //   ...
914 //   EXEPCT_CALL(mock, Foo("abc", _, _))
915 //       .WillOnce(Invoke(DistanceToOriginWithLabel));
916 //   EXEPCT_CALL(mock, Bar(5, _, _))
917 //       .WillOnce(Invoke(DistanceToOriginWithIndex));
918 //
919 // you could write
920 //
921 //   // We can declare any uninteresting argument as Unused.
922 //   double DistanceToOrigin(Unused, double x, double y) {
923 //     return sqrt(x*x + y*y);
924 //   }
925 //   ...
926 //   EXEPCT_CALL(mock, Foo("abc", _, _)).WillOnce(Invoke(DistanceToOrigin));
927 //   EXEPCT_CALL(mock, Bar(5, _, _)).WillOnce(Invoke(DistanceToOrigin));
928 typedef internal::IgnoredValue Unused;
929 
930 // This constructor allows us to turn an Action<From> object into an
931 // Action<To>, as long as To's arguments can be implicitly converted
932 // to From's and From's return type cann be implicitly converted to
933 // To's.
934 template <typename To>
935 template <typename From>
Action(const Action<From> & from)936 Action<To>::Action(const Action<From>& from)
937     : impl_(new internal::ActionAdaptor<To, From>(from)) {}
938 
939 // Creates an action that returns 'value'.  'value' is passed by value
940 // instead of const reference - otherwise Return("string literal")
941 // will trigger a compiler error about using array as initializer.
942 template <typename R>
Return(R value)943 internal::ReturnAction<R> Return(R value) {
944   return internal::ReturnAction<R>(value);
945 }
946 
947 // Creates an action that returns NULL.
ReturnNull()948 inline PolymorphicAction<internal::ReturnNullAction> ReturnNull() {
949   return MakePolymorphicAction(internal::ReturnNullAction());
950 }
951 
952 // Creates an action that returns from a void function.
Return()953 inline PolymorphicAction<internal::ReturnVoidAction> Return() {
954   return MakePolymorphicAction(internal::ReturnVoidAction());
955 }
956 
957 // Creates an action that returns the reference to a variable.
958 template <typename R>
ReturnRef(R & x)959 inline internal::ReturnRefAction<R> ReturnRef(R& x) {  // NOLINT
960   return internal::ReturnRefAction<R>(x);
961 }
962 
963 // Creates an action that returns the reference to a copy of the
964 // argument.  The copy is created when the action is constructed and
965 // lives as long as the action.
966 template <typename R>
ReturnRefOfCopy(const R & x)967 inline internal::ReturnRefOfCopyAction<R> ReturnRefOfCopy(const R& x) {
968   return internal::ReturnRefOfCopyAction<R>(x);
969 }
970 
971 // Creates an action that does the default action for the give mock function.
DoDefault()972 inline internal::DoDefaultAction DoDefault() {
973   return internal::DoDefaultAction();
974 }
975 
976 // Creates an action that sets the variable pointed by the N-th
977 // (0-based) function argument to 'value'.
978 template <size_t N, typename T>
979 PolymorphicAction<
980   internal::SetArgumentPointeeAction<
981     N, T, internal::IsAProtocolMessage<T>::value> >
SetArgPointee(const T & x)982 SetArgPointee(const T& x) {
983   return MakePolymorphicAction(internal::SetArgumentPointeeAction<
984       N, T, internal::IsAProtocolMessage<T>::value>(x));
985 }
986 
987 #if !((GTEST_GCC_VER_ && GTEST_GCC_VER_ < 40000) || GTEST_OS_SYMBIAN)
988 // This overload allows SetArgPointee() to accept a string literal.
989 // GCC prior to the version 4.0 and Symbian C++ compiler cannot distinguish
990 // this overload from the templated version and emit a compile error.
991 template <size_t N>
992 PolymorphicAction<
993   internal::SetArgumentPointeeAction<N, const char*, false> >
SetArgPointee(const char * p)994 SetArgPointee(const char* p) {
995   return MakePolymorphicAction(internal::SetArgumentPointeeAction<
996       N, const char*, false>(p));
997 }
998 
999 template <size_t N>
1000 PolymorphicAction<
1001   internal::SetArgumentPointeeAction<N, const wchar_t*, false> >
SetArgPointee(const wchar_t * p)1002 SetArgPointee(const wchar_t* p) {
1003   return MakePolymorphicAction(internal::SetArgumentPointeeAction<
1004       N, const wchar_t*, false>(p));
1005 }
1006 #endif
1007 
1008 // The following version is DEPRECATED.
1009 template <size_t N, typename T>
1010 PolymorphicAction<
1011   internal::SetArgumentPointeeAction<
1012     N, T, internal::IsAProtocolMessage<T>::value> >
SetArgumentPointee(const T & x)1013 SetArgumentPointee(const T& x) {
1014   return MakePolymorphicAction(internal::SetArgumentPointeeAction<
1015       N, T, internal::IsAProtocolMessage<T>::value>(x));
1016 }
1017 
1018 // Creates an action that sets a pointer referent to a given value.
1019 template <typename T1, typename T2>
Assign(T1 * ptr,T2 val)1020 PolymorphicAction<internal::AssignAction<T1, T2> > Assign(T1* ptr, T2 val) {
1021   return MakePolymorphicAction(internal::AssignAction<T1, T2>(ptr, val));
1022 }
1023 
1024 #if !GTEST_OS_WINDOWS_MOBILE
1025 
1026 // Creates an action that sets errno and returns the appropriate error.
1027 template <typename T>
1028 PolymorphicAction<internal::SetErrnoAndReturnAction<T> >
SetErrnoAndReturn(int errval,T result)1029 SetErrnoAndReturn(int errval, T result) {
1030   return MakePolymorphicAction(
1031       internal::SetErrnoAndReturnAction<T>(errval, result));
1032 }
1033 
1034 #endif  // !GTEST_OS_WINDOWS_MOBILE
1035 
1036 // Various overloads for InvokeWithoutArgs().
1037 
1038 // Creates an action that invokes 'function_impl' with no argument.
1039 template <typename FunctionImpl>
1040 PolymorphicAction<internal::InvokeWithoutArgsAction<FunctionImpl> >
InvokeWithoutArgs(FunctionImpl function_impl)1041 InvokeWithoutArgs(FunctionImpl function_impl) {
1042   return MakePolymorphicAction(
1043       internal::InvokeWithoutArgsAction<FunctionImpl>(function_impl));
1044 }
1045 
1046 // Creates an action that invokes the given method on the given object
1047 // with no argument.
1048 template <class Class, typename MethodPtr>
1049 PolymorphicAction<internal::InvokeMethodWithoutArgsAction<Class, MethodPtr> >
InvokeWithoutArgs(Class * obj_ptr,MethodPtr method_ptr)1050 InvokeWithoutArgs(Class* obj_ptr, MethodPtr method_ptr) {
1051   return MakePolymorphicAction(
1052       internal::InvokeMethodWithoutArgsAction<Class, MethodPtr>(
1053           obj_ptr, method_ptr));
1054 }
1055 
1056 // Creates an action that performs an_action and throws away its
1057 // result.  In other words, it changes the return type of an_action to
1058 // void.  an_action MUST NOT return void, or the code won't compile.
1059 template <typename A>
IgnoreResult(const A & an_action)1060 inline internal::IgnoreResultAction<A> IgnoreResult(const A& an_action) {
1061   return internal::IgnoreResultAction<A>(an_action);
1062 }
1063 
1064 // Creates a reference wrapper for the given L-value.  If necessary,
1065 // you can explicitly specify the type of the reference.  For example,
1066 // suppose 'derived' is an object of type Derived, ByRef(derived)
1067 // would wrap a Derived&.  If you want to wrap a const Base& instead,
1068 // where Base is a base class of Derived, just write:
1069 //
1070 //   ByRef<const Base>(derived)
1071 template <typename T>
ByRef(T & l_value)1072 inline internal::ReferenceWrapper<T> ByRef(T& l_value) {  // NOLINT
1073   return internal::ReferenceWrapper<T>(l_value);
1074 }
1075 
1076 }  // namespace testing
1077 
1078 #endif  // GMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
1079