text: // Copyright 2007, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  
  // Google Mock - a framework for writing C++ mock classes.
  //
  // The ACTION* family of macros can be used in a namespace scope to
  // define custom actions easily.  The syntax:
  //
  //   ACTION(name) { statements; }
  //
  // will define an action with the given name that executes the
  // statements.  The value returned by the statements will be used as
  // the return value of the action.  Inside the statements, you can
  // refer to the K-th (0-based) argument of the mock function by
  // 'argK', and refer to its type by 'argK_type'.  For example:
  //
  //   ACTION(IncrementArg1) {
  //     arg1_type temp = arg1;
  //     return ++(*temp);
  //   }
  //
  // allows you to write
  //
  //   ...WillOnce(IncrementArg1());
  //
  // You can also refer to the entire argument tuple and its type by
  // 'args' and 'args_type', and refer to the mock function type and its
  // return type by 'function_type' and 'return_type'.
  //
  // Note that you don't need to specify the types of the mock function
  // arguments.  However rest assured that your code is still type-safe:
  // you'll get a compiler error if *arg1 doesn't support the ++
  // operator, or if the type of ++(*arg1) isn't compatible with the
  // mock function's return type, for example.
  //
  // Sometimes you'll want to parameterize the action.   For that you can use
  // another macro:
  //
  //   ACTION_P(name, param_name) { statements; }
  //
  // For example:
  //
  //   ACTION_P(Add, n) { return arg0 + n; }
  //
  // will allow you to write:
  //
  //   ...WillOnce(Add(5));
  //
  // Note that you don't need to provide the type of the parameter
  // either.  If you need to reference the type of a parameter named
  // 'foo', you can write 'foo_type'.  For example, in the body of
  // ACTION_P(Add, n) above, you can write 'n_type' to refer to the type
  // of 'n'.
  //
  // We also provide ACTION_P2, ACTION_P3, ..., up to ACTION_P10 to support
  // multi-parameter actions.
  //
  // For the purpose of typing, you can view
  //
  //   ACTION_Pk(Foo, p1, ..., pk) { ... }
  //
  // as shorthand for
  //
  //   template <typename p1_type, ..., typename pk_type>
  //   FooActionPk<p1_type, ..., pk_type> Foo(p1_type p1, ..., pk_type pk) { ... }
  //
  // In particular, you can provide the template type arguments
  // explicitly when invoking Foo(), as in Foo<long, bool>(5, false);
  // although usually you can rely on the compiler to infer the types
  // for you automatically.  You can assign the result of expression
  // Foo(p1, ..., pk) to a variable of type FooActionPk<p1_type, ...,
  // pk_type>.  This can be useful when composing actions.
  //
  // You can also overload actions with different numbers of parameters:
  //
  //   ACTION_P(Plus, a) { ... }
  //   ACTION_P2(Plus, a, b) { ... }
  //
  // While it's tempting to always use the ACTION* macros when defining
  // a new action, you should also consider implementing ActionInterface
  // or using MakePolymorphicAction() instead, especially if you need to
  // use the action a lot.  While these approaches require more work,
  // they give you more control on the types of the mock function
  // arguments and the action parameters, which in general leads to
  // better compiler error messages that pay off in the long run.  They
  // also allow overloading actions based on parameter types (as opposed
  // to just based on the number of parameters).
  //
  // CAVEAT:
  //
  // ACTION*() can only be used in a namespace scope as templates cannot be
  // declared inside of a local class.
  // Users can, however, define any local functors (e.g. a lambda) that
  // can be used as actions.
  //
  // MORE INFORMATION:
  //
  // To learn more about using these macros, please search for 'ACTION' on
  // https://github.com/google/googletest/blob/master/docs/gmock_cook_book.md
  
  #ifndef GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
  #define GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
  
  #ifndef _WIN32_WCE
  # include <errno.h>
  #endif
  
  #include <algorithm>
  #include <functional>
  #include <memory>
  #include <string>
  #include <tuple>
  #include <type_traits>
  #include <utility>
  
  #include "gmock/internal/gmock-internal-utils.h"
  #include "gmock/internal/gmock-port.h"
  #include "gmock/internal/gmock-pp.h"
  
  #ifdef _MSC_VER
  # pragma warning(push)
  # pragma warning(disable:4100)
  #endif
  
  namespace testing {
  
  // To implement an action Foo, define:
  //   1. a class FooAction that implements the ActionInterface interface, and
  //   2. a factory function that creates an Action object from a
  //      const FooAction*.
  //
  // The two-level delegation design follows that of Matcher, providing
  // consistency for extension developers.  It also eases ownership
  // management as Action objects can now be copied like plain values.
  
  namespace internal {
  
  // BuiltInDefaultValueGetter<T, true>::Get() returns a
  // default-constructed T value.  BuiltInDefaultValueGetter<T,
  // false>::Get() crashes with an error.
  //
  // This primary template is used when kDefaultConstructible is true.
  template <typename T, bool kDefaultConstructible>
  struct BuiltInDefaultValueGetter {
    static T Get() { return T(); }
  };
  template <typename T>
  struct BuiltInDefaultValueGetter<T, false> {
    static T Get() {
      Assert(false, __FILE__, __LINE__,
             "Default action undefined for the function return type.");
      return internal::Invalid<T>();
      // The above statement will never be reached, but is required in
      // order for this function to compile.
    }
  };
  
  // BuiltInDefaultValue<T>::Get() returns the "built-in" default value
  // for type T, which is NULL when T is a raw pointer type, 0 when T is
  // a numeric type, false when T is bool, or "" when T is string or
  // std::string.  In addition, in C++11 and above, it turns a
  // default-constructed T value if T is default constructible.  For any
  // other type T, the built-in default T value is undefined, and the
  // function will abort the process.
  template <typename T>
  class BuiltInDefaultValue {
   public:
    // This function returns true if and only if type T has a built-in default
    // value.
    static bool Exists() {
      return ::std::is_default_constructible<T>::value;
    }
  
    static T Get() {
      return BuiltInDefaultValueGetter<
          T, ::std::is_default_constructible<T>::value>::Get();
    }
  };
  
  // This partial specialization says that we use the same built-in
  // default value for T and const T.
  template <typename T>
  class BuiltInDefaultValue<const T> {
   public:
    static bool Exists() { return BuiltInDefaultValue<T>::Exists(); }
    static T Get() { return BuiltInDefaultValue<T>::Get(); }
  };
  
  // This partial specialization defines the default values for pointer
  // types.
  template <typename T>
  class BuiltInDefaultValue<T*> {
   public:
    static bool Exists() { return true; }
    static T* Get() { return nullptr; }
  };
  
  // The following specializations define the default values for
  // specific types we care about.
  #define GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(type, value) \
    template <> \
    class BuiltInDefaultValue<type> { \
     public: \
      static bool Exists() { return true; } \
      static type Get() { return value; } \
    }
  
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(void, );  // NOLINT
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(::std::string, "");
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(bool, false);
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned char, '\0');
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed char, '\0');
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(char, '\0');
  
  // There's no need for a default action for signed wchar_t, as that
  // type is the same as wchar_t for gcc, and invalid for MSVC.
  //
  // There's also no need for a default action for unsigned wchar_t, as
  // that type is the same as unsigned int for gcc, and invalid for
  // MSVC.
  #if GMOCK_WCHAR_T_IS_NATIVE_
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(wchar_t, 0U);  // NOLINT
  #endif
  
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned short, 0U);  // NOLINT
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed short, 0);     // NOLINT
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned int, 0U);
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed int, 0);
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned long, 0UL);  // NOLINT
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed long, 0L);     // NOLINT
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(unsigned long long, 0);  // NOLINT
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(signed long long, 0);  // NOLINT
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(float, 0);
  GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_(double, 0);
  
  #undef GMOCK_DEFINE_DEFAULT_ACTION_FOR_RETURN_TYPE_
  
  // Simple two-arg form of std::disjunction.
  template <typename P, typename Q>
  using disjunction = typename ::std::conditional<P::value, P, Q>::type;
  
  }  // namespace internal
  
  // When an unexpected function call is encountered, Google Mock will
  // let it return a default value if the user has specified one for its
  // return type, or if the return type has a built-in default value;
  // otherwise Google Mock won't know what value to return and will have
  // to abort the process.
  //
  // The DefaultValue<T> class allows a user to specify the
  // default value for a type T that is both copyable and publicly
  // destructible (i.e. anything that can be used as a function return
  // type).  The usage is:
  //
  //   // Sets the default value for type T to be foo.
  //   DefaultValue<T>::Set(foo);
  template <typename T>
  class DefaultValue {
   public:
    // Sets the default value for type T; requires T to be
    // copy-constructable and have a public destructor.
    static void Set(T x) {
      delete producer_;
      producer_ = new FixedValueProducer(x);
    }
  
    // Provides a factory function to be called to generate the default value.
    // This method can be used even if T is only move-constructible, but it is not
    // limited to that case.
    typedef T (*FactoryFunction)();
    static void SetFactory(FactoryFunction factory) {
      delete producer_;
      producer_ = new FactoryValueProducer(factory);
    }
  
    // Unsets the default value for type T.
    static void Clear() {
      delete producer_;
      producer_ = nullptr;
    }
  
    // Returns true if and only if the user has set the default value for type T.
    static bool IsSet() { return producer_ != nullptr; }
  
    // Returns true if T has a default return value set by the user or there
    // exists a built-in default value.
    static bool Exists() {
      return IsSet() || internal::BuiltInDefaultValue<T>::Exists();
    }
  
    // Returns the default value for type T if the user has set one;
    // otherwise returns the built-in default value. Requires that Exists()
    // is true, which ensures that the return value is well-defined.
    static T Get() {
      return producer_ == nullptr ? internal::BuiltInDefaultValue<T>::Get()
                                  : producer_->Produce();
    }
  
   private:
    class ValueProducer {
     public:
      virtual ~ValueProducer() {}
      virtual T Produce() = 0;
    };
  
    class FixedValueProducer : public ValueProducer {
     public:
      explicit FixedValueProducer(T value) : value_(value) {}
      T Produce() override { return value_; }
  
     private:
      const T value_;
      GTEST_DISALLOW_COPY_AND_ASSIGN_(FixedValueProducer);
    };
  
    class FactoryValueProducer : public ValueProducer {
     public:
      explicit FactoryValueProducer(FactoryFunction factory)
          : factory_(factory) {}
      T Produce() override { return factory_(); }
  
     private:
      const FactoryFunction factory_;
      GTEST_DISALLOW_COPY_AND_ASSIGN_(FactoryValueProducer);
    };
  
    static ValueProducer* producer_;
  };
  
  // This partial specialization allows a user to set default values for
  // reference types.
  template <typename T>
  class DefaultValue<T&> {
   public:
    // Sets the default value for type T&.
    static void Set(T& x) {  // NOLINT
      address_ = &x;
    }
  
    // Unsets the default value for type T&.
    static void Clear() { address_ = nullptr; }
  
    // Returns true if and only if the user has set the default value for type T&.
    static bool IsSet() { return address_ != nullptr; }
  
    // Returns true if T has a default return value set by the user or there
    // exists a built-in default value.
    static bool Exists() {
      return IsSet() || internal::BuiltInDefaultValue<T&>::Exists();
    }
  
    // Returns the default value for type T& if the user has set one;
    // otherwise returns the built-in default value if there is one;
    // otherwise aborts the process.
    static T& Get() {
      return address_ == nullptr ? internal::BuiltInDefaultValue<T&>::Get()
                                 : *address_;
    }
  
   private:
    static T* address_;
  };
  
  // This specialization allows DefaultValue<void>::Get() to
  // compile.
  template <>
  class DefaultValue<void> {
   public:
    static bool Exists() { return true; }
    static void Get() {}
  };
  
  // Points to the user-set default value for type T.
  template <typename T>
  typename DefaultValue<T>::ValueProducer* DefaultValue<T>::producer_ = nullptr;
  
  // Points to the user-set default value for type T&.
  template <typename T>
  T* DefaultValue<T&>::address_ = nullptr;
  
  // Implement this interface to define an action for function type F.
  template <typename F>
  class ActionInterface {
   public:
    typedef typename internal::Function<F>::Result Result;
    typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
  
    ActionInterface() {}
    virtual ~ActionInterface() {}
  
    // Performs the action.  This method is not const, as in general an
    // action can have side effects and be stateful.  For example, a
    // get-the-next-element-from-the-collection action will need to
    // remember the current element.
    virtual Result Perform(const ArgumentTuple& args) = 0;
  
   private:
    GTEST_DISALLOW_COPY_AND_ASSIGN_(ActionInterface);
  };
  
  // An Action<F> is a copyable and IMMUTABLE (except by assignment)
  // object that represents an action to be taken when a mock function
  // of type F is called.  The implementation of Action<T> is just a
  // std::shared_ptr to const ActionInterface<T>. Don't inherit from Action!
  // You can view an object implementing ActionInterface<F> as a
  // concrete action (including its current state), and an Action<F>
  // object as a handle to it.
  template <typename F>
  class Action {
    // Adapter class to allow constructing Action from a legacy ActionInterface.
    // New code should create Actions from functors instead.
    struct ActionAdapter {
      // Adapter must be copyable to satisfy std::function requirements.
      ::std::shared_ptr<ActionInterface<F>> impl_;
  
      template <typename... Args>
      typename internal::Function<F>::Result operator()(Args&&... args) {
        return impl_->Perform(
            ::std::forward_as_tuple(::std::forward<Args>(args)...));
      }
    };
  
    template <typename G>
    using IsCompatibleFunctor = std::is_constructible<std::function<F>, G>;
  
   public:
    typedef typename internal::Function<F>::Result Result;
    typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
  
    // Constructs a null Action.  Needed for storing Action objects in
    // STL containers.
    Action() {}
  
    // Construct an Action from a specified callable.
    // This cannot take std::function directly, because then Action would not be
    // directly constructible from lambda (it would require two conversions).
    template <
        typename G,
        typename = typename std::enable_if<internal::disjunction<
            IsCompatibleFunctor<G>, std::is_constructible<std::function<Result()>,
                                                          G>>::value>::type>
    Action(G&& fun) {  // NOLINT
      Init(::std::forward<G>(fun), IsCompatibleFunctor<G>());
    }
  
    // Constructs an Action from its implementation.
    explicit Action(ActionInterface<F>* impl)
        : fun_(ActionAdapter{::std::shared_ptr<ActionInterface<F>>(impl)}) {}
  
    // This constructor allows us to turn an Action<Func> object into an
    // Action<F>, as long as F's arguments can be implicitly converted
    // to Func's and Func's return type can be implicitly converted to F's.
    template <typename Func>
    explicit Action(const Action<Func>& action) : fun_(action.fun_) {}
  
    // Returns true if and only if this is the DoDefault() action.
    bool IsDoDefault() const { return fun_ == nullptr; }
  
    // Performs the action.  Note that this method is const even though
    // the corresponding method in ActionInterface is not.  The reason
    // is that a const Action<F> means that it cannot be re-bound to
    // another concrete action, not that the concrete action it binds to
    // cannot change state.  (Think of the difference between a const
    // pointer and a pointer to const.)
    Result Perform(ArgumentTuple args) const {
      if (IsDoDefault()) {
        internal::IllegalDoDefault(__FILE__, __LINE__);
      }
      return internal::Apply(fun_, ::std::move(args));
    }
  
   private:
    template <typename G>
    friend class Action;
  
    template <typename G>
    void Init(G&& g, ::std::true_type) {
      fun_ = ::std::forward<G>(g);
    }
  
    template <typename G>
    void Init(G&& g, ::std::false_type) {
      fun_ = IgnoreArgs<typename ::std::decay<G>::type>{::std::forward<G>(g)};
    }
  
    template <typename FunctionImpl>
    struct IgnoreArgs {
      template <typename... Args>
      Result operator()(const Args&...) const {
        return function_impl();
      }
  
      FunctionImpl function_impl;
    };
  
    // fun_ is an empty function if and only if this is the DoDefault() action.
    ::std::function<F> fun_;
  };
  
  // The PolymorphicAction class template makes it easy to implement a
  // polymorphic action (i.e. an action that can be used in mock
  // functions of than one type, e.g. Return()).
  //
  // To define a polymorphic action, a user first provides a COPYABLE
  // implementation class that has a Perform() method template:
  //
  //   class FooAction {
  //    public:
  //     template <typename Result, typename ArgumentTuple>
  //     Result Perform(const ArgumentTuple& args) const {
  //       // Processes the arguments and returns a result, using
  //       // std::get<N>(args) to get the N-th (0-based) argument in the tuple.
  //     }
  //     ...
  //   };
  //
  // Then the user creates the polymorphic action using
  // MakePolymorphicAction(object) where object has type FooAction.  See
  // the definition of Return(void) and SetArgumentPointee<N>(value) for
  // complete examples.
  template <typename Impl>
  class PolymorphicAction {
   public:
    explicit PolymorphicAction(const Impl& impl) : impl_(impl) {}
  
    template <typename F>
    operator Action<F>() const {
      return Action<F>(new MonomorphicImpl<F>(impl_));
    }
  
   private:
    template <typename F>
    class MonomorphicImpl : public ActionInterface<F> {
     public:
      typedef typename internal::Function<F>::Result Result;
      typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
  
      explicit MonomorphicImpl(const Impl& impl) : impl_(impl) {}
  
      Result Perform(const ArgumentTuple& args) override {
        return impl_.template Perform<Result>(args);
      }
  
     private:
      Impl impl_;
    };
  
    Impl impl_;
  };
  
  // Creates an Action from its implementation and returns it.  The
  // created Action object owns the implementation.
  template <typename F>
  Action<F> MakeAction(ActionInterface<F>* impl) {
    return Action<F>(impl);
  }
  
  // Creates a polymorphic action from its implementation.  This is
  // easier to use than the PolymorphicAction<Impl> constructor as it
  // doesn't require you to explicitly write the template argument, e.g.
  //
  //   MakePolymorphicAction(foo);
  // vs
  //   PolymorphicAction<TypeOfFoo>(foo);
  template <typename Impl>
  inline PolymorphicAction<Impl> MakePolymorphicAction(const Impl& impl) {
    return PolymorphicAction<Impl>(impl);
  }
  
  namespace internal {
  
  // Helper struct to specialize ReturnAction to execute a move instead of a copy
  // on return. Useful for move-only types, but could be used on any type.
  template <typename T>
  struct ByMoveWrapper {
    explicit ByMoveWrapper(T value) : payload(std::move(value)) {}
    T payload;
  };
  
  // Implements the polymorphic Return(x) action, which can be used in
  // any function that returns the type of x, regardless of the argument
  // types.
  //
  // Note: The value passed into Return must be converted into
  // Function<F>::Result when this action is cast to Action<F> rather than
  // when that action is performed. This is important in scenarios like
  //
  // MOCK_METHOD1(Method, T(U));
  // ...
  // {
  //   Foo foo;
  //   X x(&foo);
  //   EXPECT_CALL(mock, Method(_)).WillOnce(Return(x));
  // }
  //
  // In the example above the variable x holds reference to foo which leaves
  // scope and gets destroyed.  If copying X just copies a reference to foo,
  // that copy will be left with a hanging reference.  If conversion to T
  // makes a copy of foo, the above code is safe. To support that scenario, we
  // need to make sure that the type conversion happens inside the EXPECT_CALL
  // statement, and conversion of the result of Return to Action<T(U)> is a
  // good place for that.
  //
  // The real life example of the above scenario happens when an invocation
  // of gtl::Container() is passed into Return.
  //
  template <typename R>
  class ReturnAction {
   public:
    // Constructs a ReturnAction object from the value to be returned.
    // 'value' is passed by value instead of by const reference in order
    // to allow Return("string literal") to compile.
    explicit ReturnAction(R value) : value_(new R(std::move(value))) {}
  
    // This template type conversion operator allows Return(x) to be
    // used in ANY function that returns x's type.
    template <typename F>
    operator Action<F>() const {  // NOLINT
      // Assert statement belongs here because this is the best place to verify
      // conditions on F. It produces the clearest error messages
      // in most compilers.
      // Impl really belongs in this scope as a local class but can't
      // because MSVC produces duplicate symbols in different translation units
      // in this case. Until MS fixes that bug we put Impl into the class scope
      // and put the typedef both here (for use in assert statement) and
      // in the Impl class. But both definitions must be the same.
      typedef typename Function<F>::Result Result;
      GTEST_COMPILE_ASSERT_(
          !std::is_reference<Result>::value,
          use_ReturnRef_instead_of_Return_to_return_a_reference);
      static_assert(!std::is_void<Result>::value,
                    "Can't use Return() on an action expected to return `void`.");
      return Action<F>(new Impl<R, F>(value_));
    }
  
   private:
    // Implements the Return(x) action for a particular function type F.
    template <typename R_, typename F>
    class Impl : public ActionInterface<F> {
     public:
      typedef typename Function<F>::Result Result;
      typedef typename Function<F>::ArgumentTuple ArgumentTuple;
  
      // The implicit cast is necessary when Result has more than one
      // single-argument constructor (e.g. Result is std::vector<int>) and R
      // has a type conversion operator template.  In that case, value_(value)
      // won't compile as the compiler doesn't known which constructor of
      // Result to call.  ImplicitCast_ forces the compiler to convert R to
      // Result without considering explicit constructors, thus resolving the
      // ambiguity. value_ is then initialized using its copy constructor.
      explicit Impl(const std::shared_ptr<R>& value)
          : value_before_cast_(*value),
            value_(ImplicitCast_<Result>(value_before_cast_)) {}
  
      Result Perform(const ArgumentTuple&) override { return value_; }
  
     private:
      GTEST_COMPILE_ASSERT_(!std::is_reference<Result>::value,
                            Result_cannot_be_a_reference_type);
      // We save the value before casting just in case it is being cast to a
      // wrapper type.
      R value_before_cast_;
      Result value_;
  
      GTEST_DISALLOW_COPY_AND_ASSIGN_(Impl);
    };
  
    // Partially specialize for ByMoveWrapper. This version of ReturnAction will
    // move its contents instead.
    template <typename R_, typename F>
    class Impl<ByMoveWrapper<R_>, F> : public ActionInterface<F> {
     public:
      typedef typename Function<F>::Result Result;
      typedef typename Function<F>::ArgumentTuple ArgumentTuple;
  
      explicit Impl(const std::shared_ptr<R>& wrapper)
          : performed_(false), wrapper_(wrapper) {}
  
      Result Perform(const ArgumentTuple&) override {
        GTEST_CHECK_(!performed_)
            << "A ByMove() action should only be performed once.";
        performed_ = true;
        return std::move(wrapper_->payload);
      }
  
     private:
      bool performed_;
      const std::shared_ptr<R> wrapper_;
    };
  
    const std::shared_ptr<R> value_;
  };
  
  // Implements the ReturnNull() action.
  class ReturnNullAction {
   public:
    // Allows ReturnNull() to be used in any pointer-returning function. In C++11
    // this is enforced by returning nullptr, and in non-C++11 by asserting a
    // pointer type on compile time.
    template <typename Result, typename ArgumentTuple>
    static Result Perform(const ArgumentTuple&) {
      return nullptr;
    }
  };
  
  // Implements the Return() action.
  class ReturnVoidAction {
   public:
    // Allows Return() to be used in any void-returning function.
    template <typename Result, typename ArgumentTuple>
    static void Perform(const ArgumentTuple&) {
      static_assert(std::is_void<Result>::value, "Result should be void.");
    }
  };
  
  // Implements the polymorphic ReturnRef(x) action, which can be used
  // in any function that returns a reference to the type of x,
  // regardless of the argument types.
  template <typename T>
  class ReturnRefAction {
   public:
    // Constructs a ReturnRefAction object from the reference to be returned.
    explicit ReturnRefAction(T& ref) : ref_(ref) {}  // NOLINT
  
    // This template type conversion operator allows ReturnRef(x) to be
    // used in ANY function that returns a reference to x's type.
    template <typename F>
    operator Action<F>() const {
      typedef typename Function<F>::Result Result;
      // Asserts that the function return type is a reference.  This
      // catches the user error of using ReturnRef(x) when Return(x)
      // should be used, and generates some helpful error message.
      GTEST_COMPILE_ASSERT_(std::is_reference<Result>::value,
                            use_Return_instead_of_ReturnRef_to_return_a_value);
      return Action<F>(new Impl<F>(ref_));
    }
  
   private:
    // Implements the ReturnRef(x) action for a particular function type F.
    template <typename F>
    class Impl : public ActionInterface<F> {
     public:
      typedef typename Function<F>::Result Result;
      typedef typename Function<F>::ArgumentTuple ArgumentTuple;
  
      explicit Impl(T& ref) : ref_(ref) {}  // NOLINT
  
      Result Perform(const ArgumentTuple&) override { return ref_; }
  
     private:
      T& ref_;
    };
  
    T& ref_;
  };
  
  // Implements the polymorphic ReturnRefOfCopy(x) action, which can be
  // used in any function that returns a reference to the type of x,
  // regardless of the argument types.
  template <typename T>
  class ReturnRefOfCopyAction {
   public:
    // Constructs a ReturnRefOfCopyAction object from the reference to
    // be returned.
    explicit ReturnRefOfCopyAction(const T& value) : value_(value) {}  // NOLINT
  
    // This template type conversion operator allows ReturnRefOfCopy(x) to be
    // used in ANY function that returns a reference to x's type.
    template <typename F>
    operator Action<F>() const {
      typedef typename Function<F>::Result Result;
      // Asserts that the function return type is a reference.  This
      // catches the user error of using ReturnRefOfCopy(x) when Return(x)
      // should be used, and generates some helpful error message.
      GTEST_COMPILE_ASSERT_(
          std::is_reference<Result>::value,
          use_Return_instead_of_ReturnRefOfCopy_to_return_a_value);
      return Action<F>(new Impl<F>(value_));
    }
  
   private:
    // Implements the ReturnRefOfCopy(x) action for a particular function type F.
    template <typename F>
    class Impl : public ActionInterface<F> {
     public:
      typedef typename Function<F>::Result Result;
      typedef typename Function<F>::ArgumentTuple ArgumentTuple;
  
      explicit Impl(const T& value) : value_(value) {}  // NOLINT
  
      Result Perform(const ArgumentTuple&) override { return value_; }
  
     private:
      T value_;
    };
  
    const T value_;
  };
  
  // Implements the polymorphic ReturnRoundRobin(v) action, which can be
  // used in any function that returns the element_type of v.
  template <typename T>
  class ReturnRoundRobinAction {
   public:
    explicit ReturnRoundRobinAction(std::vector<T> values) {
      GTEST_CHECK_(!values.empty())
          << "ReturnRoundRobin requires at least one element.";
      state_->values = std::move(values);
    }
  
    template <typename... Args>
    T operator()(Args&&...) const {
       return state_->Next();
    }
  
   private:
    struct State {
      T Next() {
        T ret_val = values[i++];
        if (i == values.size()) i = 0;
        return ret_val;
      }
  
      std::vector<T> values;
      size_t i = 0;
    };
    std::shared_ptr<State> state_ = std::make_shared<State>();
  };
  
  // Implements the polymorphic DoDefault() action.
  class DoDefaultAction {
   public:
    // This template type conversion operator allows DoDefault() to be
    // used in any function.
    template <typename F>
    operator Action<F>() const { return Action<F>(); }  // NOLINT
  };
  
  // Implements the Assign action to set a given pointer referent to a
  // particular value.
  template <typename T1, typename T2>
  class AssignAction {
   public:
    AssignAction(T1* ptr, T2 value) : ptr_(ptr), value_(value) {}
  
    template <typename Result, typename ArgumentTuple>
    void Perform(const ArgumentTuple& /* args */) const {
      *ptr_ = value_;
    }
  
   private:
    T1* const ptr_;
    const T2 value_;
  };
  
  #if !GTEST_OS_WINDOWS_MOBILE
  
  // Implements the SetErrnoAndReturn action to simulate return from
  // various system calls and libc functions.
  template <typename T>
  class SetErrnoAndReturnAction {
   public:
    SetErrnoAndReturnAction(int errno_value, T result)
        : errno_(errno_value),
          result_(result) {}
    template <typename Result, typename ArgumentTuple>
    Result Perform(const ArgumentTuple& /* args */) const {
      errno = errno_;
      return result_;
    }
  
   private:
    const int errno_;
    const T result_;
  };
  
  #endif  // !GTEST_OS_WINDOWS_MOBILE
  
  // Implements the SetArgumentPointee<N>(x) action for any function
  // whose N-th argument (0-based) is a pointer to x's type.
  template <size_t N, typename A, typename = void>
  struct SetArgumentPointeeAction {
    A value;
  
    template <typename... Args>
    void operator()(const Args&... args) const {
      *::std::get<N>(std::tie(args...)) = value;
    }
  };
  
  // Implements the Invoke(object_ptr, &Class::Method) action.
  template <class Class, typename MethodPtr>
  struct InvokeMethodAction {
    Class* const obj_ptr;
    const MethodPtr method_ptr;
  
    template <typename... Args>
    auto operator()(Args&&... args) const
        -> decltype((obj_ptr->*method_ptr)(std::forward<Args>(args)...)) {
      return (obj_ptr->*method_ptr)(std::forward<Args>(args)...);
    }
  };
  
  // Implements the InvokeWithoutArgs(f) action.  The template argument
  // FunctionImpl is the implementation type of f, which can be either a
  // function pointer or a functor.  InvokeWithoutArgs(f) can be used as an
  // Action<F> as long as f's type is compatible with F.
  template <typename FunctionImpl>
  struct InvokeWithoutArgsAction {
    FunctionImpl function_impl;
  
    // Allows InvokeWithoutArgs(f) to be used as any action whose type is
    // compatible with f.
    template <typename... Args>
    auto operator()(const Args&...) -> decltype(function_impl()) {
      return function_impl();
    }
  };
  
  // Implements the InvokeWithoutArgs(object_ptr, &Class::Method) action.
  template <class Class, typename MethodPtr>
  struct InvokeMethodWithoutArgsAction {
    Class* const obj_ptr;
    const MethodPtr method_ptr;
  
    using ReturnType =
        decltype((std::declval<Class*>()->*std::declval<MethodPtr>())());
  
    template <typename... Args>
    ReturnType operator()(const Args&...) const {
      return (obj_ptr->*method_ptr)();
    }
  };
  
  // Implements the IgnoreResult(action) action.
  template <typename A>
  class IgnoreResultAction {
   public:
    explicit IgnoreResultAction(const A& action) : action_(action) {}
  
    template <typename F>
    operator Action<F>() const {
      // Assert statement belongs here because this is the best place to verify
      // conditions on F. It produces the clearest error messages
      // in most compilers.
      // Impl really belongs in this scope as a local class but can't
      // because MSVC produces duplicate symbols in different translation units
      // in this case. Until MS fixes that bug we put Impl into the class scope
      // and put the typedef both here (for use in assert statement) and
      // in the Impl class. But both definitions must be the same.
      typedef typename internal::Function<F>::Result Result;
  
      // Asserts at compile time that F returns void.
      static_assert(std::is_void<Result>::value, "Result type should be void.");
  
      return Action<F>(new Impl<F>(action_));
    }
  
   private:
    template <typename F>
    class Impl : public ActionInterface<F> {
     public:
      typedef typename internal::Function<F>::Result Result;
      typedef typename internal::Function<F>::ArgumentTuple ArgumentTuple;
  
      explicit Impl(const A& action) : action_(action) {}
  
      void Perform(const ArgumentTuple& args) override {
        // Performs the action and ignores its result.
        action_.Perform(args);
      }
  
     private:
      // Type OriginalFunction is the same as F except that its return
      // type is IgnoredValue.
      typedef typename internal::Function<F>::MakeResultIgnoredValue
          OriginalFunction;
  
      const Action<OriginalFunction> action_;
    };
  
    const A action_;
  };
  
  template <typename InnerAction, size_t... I>
  struct WithArgsAction {
    InnerAction action;
  
    // The inner action could be anything convertible to Action<X>.
    // We use the conversion operator to detect the signature of the inner Action.
    template <typename R, typename... Args>
    operator Action<R(Args...)>() const {  // NOLINT
      using TupleType = std::tuple<Args...>;
      Action<R(typename std::tuple_element<I, TupleType>::type...)>
          converted(action);
  
      return [converted](Args... args) -> R {
        return converted.Perform(std::forward_as_tuple(
          std::get<I>(std::forward_as_tuple(std::forward<Args>(args)...))...));
      };
    }
  };
  
  template <typename... Actions>
  struct DoAllAction {
   private:
    template <typename T>
    using NonFinalType =
        typename std::conditional<std::is_scalar<T>::value, T, const T&>::type;
  
    template <typename ActionT, size_t... I>
    std::vector<ActionT> Convert(IndexSequence<I...>) const {
      return {ActionT(std::get<I>(actions))...};
    }
  
   public:
    std::tuple<Actions...> actions;
  
    template <typename R, typename... Args>
    operator Action<R(Args...)>() const {  // NOLINT
      struct Op {
        std::vector<Action<void(NonFinalType<Args>...)>> converted;
        Action<R(Args...)> last;
        R operator()(Args... args) const {
          auto tuple_args = std::forward_as_tuple(std::forward<Args>(args)...);
          for (auto& a : converted) {
            a.Perform(tuple_args);
          }
          return last.Perform(std::move(tuple_args));
        }
      };
      return Op{Convert<Action<void(NonFinalType<Args>...)>>(
                    MakeIndexSequence<sizeof...(Actions) - 1>()),
                std::get<sizeof...(Actions) - 1>(actions)};
    }
  };
  
  template <typename T, typename... Params>
  struct ReturnNewAction {
    T* operator()() const {
      return internal::Apply(
          [](const Params&... unpacked_params) {
            return new T(unpacked_params...);
          },
          params);
    }
    std::tuple<Params...> params;
  };
  
  template <size_t k>
  struct ReturnArgAction {
    template <typename... Args>
    auto operator()(const Args&... args) const ->
        typename std::tuple_element<k, std::tuple<Args...>>::type {
      return std::get<k>(std::tie(args...));
    }
  };
  
  template <size_t k, typename Ptr>
  struct SaveArgAction {
    Ptr pointer;
  
    template <typename... Args>
    void operator()(const Args&... args) const {
      *pointer = std::get<k>(std::tie(args...));
    }
  };
  
  template <size_t k, typename Ptr>
  struct SaveArgPointeeAction {
    Ptr pointer;
  
    template <typename... Args>
    void operator()(const Args&... args) const {
      *pointer = *std::get<k>(std::tie(args...));
    }
  };
  
  template <size_t k, typename T>
  struct SetArgRefereeAction {
    T value;
  
    template <typename... Args>
    void operator()(Args&&... args) const {
      using argk_type =
          typename ::std::tuple_element<k, std::tuple<Args...>>::type;
      static_assert(std::is_lvalue_reference<argk_type>::value,
                    "Argument must be a reference type.");
      std::get<k>(std::tie(args...)) = value;
    }
  };
  
  template <size_t k, typename I1, typename I2>
  struct SetArrayArgumentAction {
    I1 first;
    I2 last;
  
    template <typename... Args>
    void operator()(const Args&... args) const {
      auto value = std::get<k>(std::tie(args...));
      for (auto it = first; it != last; ++it, (void)++value) {
        *value = *it;
      }
    }
  };
  
  template <size_t k>
  struct DeleteArgAction {
    template <typename... Args>
    void operator()(const Args&... args) const {
      delete std::get<k>(std::tie(args...));
    }
  };
  
  template <typename Ptr>
  struct ReturnPointeeAction {
    Ptr pointer;
    template <typename... Args>
    auto operator()(const Args&...) const -> decltype(*pointer) {
      return *pointer;
    }
  };
  
  #if GTEST_HAS_EXCEPTIONS
  template <typename T>
  struct ThrowAction {
    T exception;
    // We use a conversion operator to adapt to any return type.
    template <typename R, typename... Args>
    operator Action<R(Args...)>() const {  // NOLINT
      T copy = exception;
      return [copy](Args...) -> R { throw copy; };
    }
  };
  #endif  // GTEST_HAS_EXCEPTIONS
  
  }  // namespace internal
  
  // An Unused object can be implicitly constructed from ANY value.
  // This is handy when defining actions that ignore some or all of the
  // mock function arguments.  For example, given
  //
  //   MOCK_METHOD3(Foo, double(const string& label, double x, double y));
  //   MOCK_METHOD3(Bar, double(int index, double x, double y));
  //
  // instead of
  //
  //   double DistanceToOriginWithLabel(const string& label, double x, double y) {
  //     return sqrt(x*x + y*y);
  //   }
  //   double DistanceToOriginWithIndex(int index, double x, double y) {
  //     return sqrt(x*x + y*y);
  //   }
  //   ...
  //   EXPECT_CALL(mock, Foo("abc", _, _))
  //       .WillOnce(Invoke(DistanceToOriginWithLabel));
  //   EXPECT_CALL(mock, Bar(5, _, _))
  //       .WillOnce(Invoke(DistanceToOriginWithIndex));
  //
  // you could write
  //
  //   // We can declare any uninteresting argument as Unused.
  //   double DistanceToOrigin(Unused, double x, double y) {
  //     return sqrt(x*x + y*y);
  //   }
  //   ...
  //   EXPECT_CALL(mock, Foo("abc", _, _)).WillOnce(Invoke(DistanceToOrigin));
  //   EXPECT_CALL(mock, Bar(5, _, _)).WillOnce(Invoke(DistanceToOrigin));
  typedef internal::IgnoredValue Unused;
  
  // Creates an action that does actions a1, a2, ..., sequentially in
  // each invocation. All but the last action will have a readonly view of the
  // arguments.
  template <typename... Action>
  internal::DoAllAction<typename std::decay<Action>::type...> DoAll(
      Action&&... action) {
    return {std::forward_as_tuple(std::forward<Action>(action)...)};
  }
  
  // WithArg<k>(an_action) creates an action that passes the k-th
  // (0-based) argument of the mock function to an_action and performs
  // it.  It adapts an action accepting one argument to one that accepts
  // multiple arguments.  For convenience, we also provide
  // WithArgs<k>(an_action) (defined below) as a synonym.
  template <size_t k, typename InnerAction>
  internal::WithArgsAction<typename std::decay<InnerAction>::type, k>
  WithArg(InnerAction&& action) {
    return {std::forward<InnerAction>(action)};
  }
  
  // WithArgs<N1, N2, ..., Nk>(an_action) creates an action that passes
  // the selected arguments of the mock function to an_action and
  // performs it.  It serves as an adaptor between actions with
  // different argument lists.
  template <size_t k, size_t... ks, typename InnerAction>
  internal::WithArgsAction<typename std::decay<InnerAction>::type, k, ks...>
  WithArgs(InnerAction&& action) {
    return {std::forward<InnerAction>(action)};
  }
  
  // WithoutArgs(inner_action) can be used in a mock function with a
  // non-empty argument list to perform inner_action, which takes no
  // argument.  In other words, it adapts an action accepting no
  // argument to one that accepts (and ignores) arguments.
  template <typename InnerAction>
  internal::WithArgsAction<typename std::decay<InnerAction>::type>
  WithoutArgs(InnerAction&& action) {
    return {std::forward<InnerAction>(action)};
  }
  
  // Creates an action that returns 'value'.  'value' is passed by value
  // instead of const reference - otherwise Return("string literal")
  // will trigger a compiler error about using array as initializer.
  template <typename R>
  internal::ReturnAction<R> Return(R value) {
    return internal::ReturnAction<R>(std::move(value));
  }
  
  // Creates an action that returns NULL.
  inline PolymorphicAction<internal::ReturnNullAction> ReturnNull() {
    return MakePolymorphicAction(internal::ReturnNullAction());
  }
  
  // Creates an action that returns from a void function.
  inline PolymorphicAction<internal::ReturnVoidAction> Return() {
    return MakePolymorphicAction(internal::ReturnVoidAction());
  }
  
  // Creates an action that returns the reference to a variable.
  template <typename R>
  inline internal::ReturnRefAction<R> ReturnRef(R& x) {  // NOLINT
    return internal::ReturnRefAction<R>(x);
  }
  
  // Prevent using ReturnRef on reference to temporary.
  template <typename R, R* = nullptr>
  internal::ReturnRefAction<R> ReturnRef(R&&) = delete;
  
  // Creates an action that returns the reference to a copy of the
  // argument.  The copy is created when the action is constructed and
  // lives as long as the action.
  template <typename R>
  inline internal::ReturnRefOfCopyAction<R> ReturnRefOfCopy(const R& x) {
    return internal::ReturnRefOfCopyAction<R>(x);
  }
  
  // Modifies the parent action (a Return() action) to perform a move of the
  // argument instead of a copy.
  // Return(ByMove()) actions can only be executed once and will assert this
  // invariant.
  template <typename R>
  internal::ByMoveWrapper<R> ByMove(R x) {
    return internal::ByMoveWrapper<R>(std::move(x));
  }
  
  // Creates an action that returns an element of `vals`. Calling this action will
  // repeatedly return the next value from `vals` until it reaches the end and
  // will restart from the beginning.
  template <typename T>
  internal::ReturnRoundRobinAction<T> ReturnRoundRobin(std::vector<T> vals) {
    return internal::ReturnRoundRobinAction<T>(std::move(vals));
  }
  
  // Creates an action that returns an element of `vals`. Calling this action will
  // repeatedly return the next value from `vals` until it reaches the end and
  // will restart from the beginning.
  template <typename T>
  internal::ReturnRoundRobinAction<T> ReturnRoundRobin(
      std::initializer_list<T> vals) {
    return internal::ReturnRoundRobinAction<T>(std::vector<T>(vals));
  }
  
  // Creates an action that does the default action for the give mock function.
  inline internal::DoDefaultAction DoDefault() {
    return internal::DoDefaultAction();
  }
  
  // Creates an action that sets the variable pointed by the N-th
  // (0-based) function argument to 'value'.
  template <size_t N, typename T>
  internal::SetArgumentPointeeAction<N, T> SetArgPointee(T value) {
    return {std::move(value)};
  }
  
  // The following version is DEPRECATED.
  template <size_t N, typename T>
  internal::SetArgumentPointeeAction<N, T> SetArgumentPointee(T value) {
    return {std::move(value)};
  }
  
  // Creates an action that sets a pointer referent to a given value.
  template <typename T1, typename T2>
  PolymorphicAction<internal::AssignAction<T1, T2> > Assign(T1* ptr, T2 val) {
    return MakePolymorphicAction(internal::AssignAction<T1, T2>(ptr, val));
  }
  
  #if !GTEST_OS_WINDOWS_MOBILE
  
  // Creates an action that sets errno and returns the appropriate error.
  template <typename T>
  PolymorphicAction<internal::SetErrnoAndReturnAction<T> >
  SetErrnoAndReturn(int errval, T result) {
    return MakePolymorphicAction(
        internal::SetErrnoAndReturnAction<T>(errval, result));
  }
  
  #endif  // !GTEST_OS_WINDOWS_MOBILE
  
  // Various overloads for Invoke().
  
  // Legacy function.
  // Actions can now be implicitly constructed from callables. No need to create
  // wrapper objects.
  // This function exists for backwards compatibility.
  template <typename FunctionImpl>
  typename std::decay<FunctionImpl>::type Invoke(FunctionImpl&& function_impl) {
    return std::forward<FunctionImpl>(function_impl);
  }
  
  // Creates an action that invokes the given method on the given object
  // with the mock function's arguments.
  template <class Class, typename MethodPtr>
  internal::InvokeMethodAction<Class, MethodPtr> Invoke(Class* obj_ptr,
                                                        MethodPtr method_ptr) {
    return {obj_ptr, method_ptr};
  }
  
  // Creates an action that invokes 'function_impl' with no argument.
  template <typename FunctionImpl>
  internal::InvokeWithoutArgsAction<typename std::decay<FunctionImpl>::type>
  InvokeWithoutArgs(FunctionImpl function_impl) {
    return {std::move(function_impl)};
  }
  
  // Creates an action that invokes the given method on the given object
  // with no argument.
  template <class Class, typename MethodPtr>
  internal::InvokeMethodWithoutArgsAction<Class, MethodPtr> InvokeWithoutArgs(
      Class* obj_ptr, MethodPtr method_ptr) {
    return {obj_ptr, method_ptr};
  }
  
  // Creates an action that performs an_action and throws away its
  // result.  In other words, it changes the return type of an_action to
  // void.  an_action MUST NOT return void, or the code won't compile.
  template <typename A>
  inline internal::IgnoreResultAction<A> IgnoreResult(const A& an_action) {
    return internal::IgnoreResultAction<A>(an_action);
  }
  
  // Creates a reference wrapper for the given L-value.  If necessary,
  // you can explicitly specify the type of the reference.  For example,
  // suppose 'derived' is an object of type Derived, ByRef(derived)
  // would wrap a Derived&.  If you want to wrap a const Base& instead,
  // where Base is a base class of Derived, just write:
  //
  //   ByRef<const Base>(derived)
  //
  // N.B. ByRef is redundant with std::ref, std::cref and std::reference_wrapper.
  // However, it may still be used for consistency with ByMove().
  template <typename T>
  inline ::std::reference_wrapper<T> ByRef(T& l_value) {  // NOLINT
    return ::std::reference_wrapper<T>(l_value);
  }
  
  // The ReturnNew<T>(a1, a2, ..., a_k) action returns a pointer to a new
  // instance of type T, constructed on the heap with constructor arguments
  // a1, a2, ..., and a_k. The caller assumes ownership of the returned value.
  template <typename T, typename... Params>
  internal::ReturnNewAction<T, typename std::decay<Params>::type...> ReturnNew(
      Params&&... params) {
    return {std::forward_as_tuple(std::forward<Params>(params)...)};
  }
  
  // Action ReturnArg<k>() returns the k-th argument of the mock function.
  template <size_t k>
  internal::ReturnArgAction<k> ReturnArg() {
    return {};
  }
  
  // Action SaveArg<k>(pointer) saves the k-th (0-based) argument of the
  // mock function to *pointer.
  template <size_t k, typename Ptr>
  internal::SaveArgAction<k, Ptr> SaveArg(Ptr pointer) {
    return {pointer};
  }
  
  // Action SaveArgPointee<k>(pointer) saves the value pointed to
  // by the k-th (0-based) argument of the mock function to *pointer.
  template <size_t k, typename Ptr>
  internal::SaveArgPointeeAction<k, Ptr> SaveArgPointee(Ptr pointer) {
    return {pointer};
  }
  
  // Action SetArgReferee<k>(value) assigns 'value' to the variable
  // referenced by the k-th (0-based) argument of the mock function.
  template <size_t k, typename T>
  internal::SetArgRefereeAction<k, typename std::decay<T>::type> SetArgReferee(
      T&& value) {
    return {std::forward<T>(value)};
  }
  
  // Action SetArrayArgument<k>(first, last) copies the elements in
  // source range [first, last) to the array pointed to by the k-th
  // (0-based) argument, which can be either a pointer or an
  // iterator. The action does not take ownership of the elements in the
  // source range.
  template <size_t k, typename I1, typename I2>
  internal::SetArrayArgumentAction<k, I1, I2> SetArrayArgument(I1 first,
                                                               I2 last) {
    return {first, last};
  }
  
  // Action DeleteArg<k>() deletes the k-th (0-based) argument of the mock
  // function.
  template <size_t k>
  internal::DeleteArgAction<k> DeleteArg() {
    return {};
  }
  
  // This action returns the value pointed to by 'pointer'.
  template <typename Ptr>
  internal::ReturnPointeeAction<Ptr> ReturnPointee(Ptr pointer) {
    return {pointer};
  }
  
  // Action Throw(exception) can be used in a mock function of any type
  // to throw the given exception.  Any copyable value can be thrown.
  #if GTEST_HAS_EXCEPTIONS
  template <typename T>
  internal::ThrowAction<typename std::decay<T>::type> Throw(T&& exception) {
    return {std::forward<T>(exception)};
  }
  #endif  // GTEST_HAS_EXCEPTIONS
  
  namespace internal {
  
  // A macro from the ACTION* family (defined later in gmock-generated-actions.h)
  // defines an action that can be used in a mock function.  Typically,
  // these actions only care about a subset of the arguments of the mock
  // function.  For example, if such an action only uses the second
  // argument, it can be used in any mock function that takes >= 2
  // arguments where the type of the second argument is compatible.
  //
  // Therefore, the action implementation must be prepared to take more
  // arguments than it needs.  The ExcessiveArg type is used to
  // represent those excessive arguments.  In order to keep the compiler
  // error messages tractable, we define it in the ::testing namespace
  // instead of ::testing::internal.  However, this is an INTERNAL TYPE
  // and subject to change without notice, so a user MUST NOT USE THIS
  // TYPE DIRECTLY.
  struct ExcessiveArg {};
  
  // Builds an implementation of an Action<> for some particular signature, using
  // a class defined by an ACTION* macro.
  template <typename F, typename Impl> struct ActionImpl;
  
  template <typename Impl>
  struct ImplBase {
    struct Holder {
      // Allows each copy of the Action<> to get to the Impl.
      explicit operator const Impl&() const { return *ptr; }
      std::shared_ptr<Impl> ptr;
    };
    using type = typename std::conditional<std::is_constructible<Impl>::value,
                                           Impl, Holder>::type;
  };
  
  template <typename R, typename... Args, typename Impl>
  struct ActionImpl<R(Args...), Impl> : ImplBase<Impl>::type {
    using Base = typename ImplBase<Impl>::type;
    using function_type = R(Args...);
    using args_type = std::tuple<Args...>;
  
    ActionImpl() = default;  // Only defined if appropriate for Base.
    explicit ActionImpl(std::shared_ptr<Impl> impl) : Base{std::move(impl)} { }
  
    R operator()(Args&&... arg) const {
      static constexpr size_t kMaxArgs =
          sizeof...(Args) <= 10 ? sizeof...(Args) : 10;
      return Apply(MakeIndexSequence<kMaxArgs>{},
                   MakeIndexSequence<10 - kMaxArgs>{},
                   args_type{std::forward<Args>(arg)...});
    }
  
    template <std::size_t... arg_id, std::size_t... excess_id>
    R Apply(IndexSequence<arg_id...>, IndexSequence<excess_id...>,
            const args_type& args) const {
      // Impl need not be specific to the signature of action being implemented;
      // only the implementing function body needs to have all of the specific
      // types instantiated.  Up to 10 of the args that are provided by the
      // args_type get passed, followed by a dummy of unspecified type for the
      // remainder up to 10 explicit args.
      static constexpr ExcessiveArg kExcessArg{};
      return static_cast<const Impl&>(*this).template gmock_PerformImpl<
          /*function_type=*/function_type, /*return_type=*/R,
          /*args_type=*/args_type,
          /*argN_type=*/typename std::tuple_element<arg_id, args_type>::type...>(
          /*args=*/args, std::get<arg_id>(args)...,
          ((void)excess_id, kExcessArg)...);
    }
  };
  
  // Stores a default-constructed Impl as part of the Action<>'s
  // std::function<>. The Impl should be trivial to copy.
  template <typename F, typename Impl>
  ::testing::Action<F> MakeAction() {
    return ::testing::Action<F>(ActionImpl<F, Impl>());
  }
  
  // Stores just the one given instance of Impl.
  template <typename F, typename Impl>
  ::testing::Action<F> MakeAction(std::shared_ptr<Impl> impl) {
    return ::testing::Action<F>(ActionImpl<F, Impl>(std::move(impl)));
  }
  
  #define GMOCK_INTERNAL_ARG_UNUSED(i, data, el) \
    , const arg##i##_type& arg##i GTEST_ATTRIBUTE_UNUSED_
  #define GMOCK_ACTION_ARG_TYPES_AND_NAMES_UNUSED_           \
    const args_type& args GTEST_ATTRIBUTE_UNUSED_ GMOCK_PP_REPEAT( \
        GMOCK_INTERNAL_ARG_UNUSED, , 10)
  
  #define GMOCK_INTERNAL_ARG(i, data, el) , const arg##i##_type& arg##i
  #define GMOCK_ACTION_ARG_TYPES_AND_NAMES_ \
    const args_type& args GMOCK_PP_REPEAT(GMOCK_INTERNAL_ARG, , 10)
  
  #define GMOCK_INTERNAL_TEMPLATE_ARG(i, data, el) , typename arg##i##_type
  #define GMOCK_ACTION_TEMPLATE_ARGS_NAMES_ \
    GMOCK_PP_TAIL(GMOCK_PP_REPEAT(GMOCK_INTERNAL_TEMPLATE_ARG, , 10))
  
  #define GMOCK_INTERNAL_TYPENAME_PARAM(i, data, param) , typename param##_type
  #define GMOCK_ACTION_TYPENAME_PARAMS_(params) \
    GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_TYPENAME_PARAM, , params))
  
  #define GMOCK_INTERNAL_TYPE_PARAM(i, data, param) , param##_type
  #define GMOCK_ACTION_TYPE_PARAMS_(params) \
    GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_TYPE_PARAM, , params))
  
  #define GMOCK_INTERNAL_TYPE_GVALUE_PARAM(i, data, param) \
    , param##_type gmock_p##i
  #define GMOCK_ACTION_TYPE_GVALUE_PARAMS_(params) \
    GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_TYPE_GVALUE_PARAM, , params))
  
  #define GMOCK_INTERNAL_GVALUE_PARAM(i, data, param) \
    , std::forward<param##_type>(gmock_p##i)
  #define GMOCK_ACTION_GVALUE_PARAMS_(params) \
    GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_GVALUE_PARAM, , params))
  
  #define GMOCK_INTERNAL_INIT_PARAM(i, data, param) \
    , param(::std::forward<param##_type>(gmock_p##i))
  #define GMOCK_ACTION_INIT_PARAMS_(params) \
    GMOCK_PP_TAIL(GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_INIT_PARAM, , params))
  
  #define GMOCK_INTERNAL_FIELD_PARAM(i, data, param) param##_type param;
  #define GMOCK_ACTION_FIELD_PARAMS_(params) \
    GMOCK_PP_FOR_EACH(GMOCK_INTERNAL_FIELD_PARAM, , params)
  
  #define GMOCK_INTERNAL_ACTION(name, full_name, params)                        \
    template <GMOCK_ACTION_TYPENAME_PARAMS_(params)>                            \
    class full_name {                                                           \
     public:                                                                    \
      explicit full_name(GMOCK_ACTION_TYPE_GVALUE_PARAMS_(params))              \
          : impl_(std::make_shared<gmock_Impl>(                                 \
                  GMOCK_ACTION_GVALUE_PARAMS_(params))) { }                     \
      full_name(const full_name&) = default;                                    \
      full_name(full_name&&) noexcept = default;                                \
      template <typename F>                                                     \
      operator ::testing::Action<F>() const {                                   \
        return ::testing::internal::MakeAction<F>(impl_);                       \
      }                                                                         \
     private:                                                                   \
      class gmock_Impl {                                                        \
       public:                                                                  \
        explicit gmock_Impl(GMOCK_ACTION_TYPE_GVALUE_PARAMS_(params))           \
            : GMOCK_ACTION_INIT_PARAMS_(params) {}                              \
        template <typename function_type, typename return_type,                 \
                  typename args_type, GMOCK_ACTION_TEMPLATE_ARGS_NAMES_>        \
        return_type gmock_PerformImpl(GMOCK_ACTION_ARG_TYPES_AND_NAMES_) const; \
        GMOCK_ACTION_FIELD_PARAMS_(params)                                      \
      };                                                                        \
      std::shared_ptr<const gmock_Impl> impl_;                                  \
    };                                                                          \
    template <GMOCK_ACTION_TYPENAME_PARAMS_(params)>                            \
    inline full_name<GMOCK_ACTION_TYPE_PARAMS_(params)> name(                   \
        GMOCK_ACTION_TYPE_GVALUE_PARAMS_(params)) {                             \
      return full_name<GMOCK_ACTION_TYPE_PARAMS_(params)>(                      \
          GMOCK_ACTION_GVALUE_PARAMS_(params));                                 \
    }                                                                           \
    template <GMOCK_ACTION_TYPENAME_PARAMS_(params)>                            \
    template <typename function_type, typename return_type, typename args_type, \
              GMOCK_ACTION_TEMPLATE_ARGS_NAMES_>                                \
    return_type full_name<GMOCK_ACTION_TYPE_PARAMS_(params)>::gmock_Impl::      \
    gmock_PerformImpl(GMOCK_ACTION_ARG_TYPES_AND_NAMES_UNUSED_) const
  
  }  // namespace internal
  
  // Similar to GMOCK_INTERNAL_ACTION, but no bound parameters are stored.
  #define ACTION(name)                                                          \
    class name##Action {                                                        \
     public:                                                                    \
     explicit name##Action() noexcept {}                                        \
     name##Action(const name##Action&) noexcept {}                              \
      template <typename F>                                                     \
      operator ::testing::Action<F>() const {                                   \
        return ::testing::internal::MakeAction<F, gmock_Impl>();                \
      }                                                                         \
     private:                                                                   \
      class gmock_Impl {                                                        \
       public:                                                                  \
        template <typename function_type, typename return_type,                 \
                  typename args_type, GMOCK_ACTION_TEMPLATE_ARGS_NAMES_>        \
        return_type gmock_PerformImpl(GMOCK_ACTION_ARG_TYPES_AND_NAMES_) const; \
      };                                                                        \
    };                                                                          \
    inline name##Action name() GTEST_MUST_USE_RESULT_;                          \
    inline name##Action name() { return name##Action(); }                       \
    template <typename function_type, typename return_type, typename args_type, \
              GMOCK_ACTION_TEMPLATE_ARGS_NAMES_>                                \
    return_type name##Action::gmock_Impl::gmock_PerformImpl(                    \
        GMOCK_ACTION_ARG_TYPES_AND_NAMES_UNUSED_) const
  
  #define ACTION_P(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP, (__VA_ARGS__))
  
  #define ACTION_P2(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP2, (__VA_ARGS__))
  
  #define ACTION_P3(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP3, (__VA_ARGS__))
  
  #define ACTION_P4(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP4, (__VA_ARGS__))
  
  #define ACTION_P5(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP5, (__VA_ARGS__))
  
  #define ACTION_P6(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP6, (__VA_ARGS__))
  
  #define ACTION_P7(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP7, (__VA_ARGS__))
  
  #define ACTION_P8(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP8, (__VA_ARGS__))
  
  #define ACTION_P9(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP9, (__VA_ARGS__))
  
  #define ACTION_P10(name, ...) \
    GMOCK_INTERNAL_ACTION(name, name##ActionP10, (__VA_ARGS__))
  
  }  // namespace testing
  
  #ifdef _MSC_VER
  # pragma warning(pop)
  #endif
  
  #endif  // GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_ACTIONS_H_
  