Add ByMove() modifier for the Return() action. Pull in gtest 695.

include/gmock/gmock-actions.h

@@ -459,6 +459,14 @@ class ActionAdaptor : public ActionInterface<F1> {
   GTEST_DISALLOW_ASSIGN_(ActionAdaptor);
 };
 
+// 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(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.
@@ -489,7 +497,7 @@ class ReturnAction {
   // 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_(value) {}
+  explicit ReturnAction(R value) : value_(new R(move(value))) {}
 
   // This template type conversion operator allows Return(x) to be
   // used in ANY function that returns x's type.
@@ -505,14 +513,14 @@ class ReturnAction {
     // in the Impl class. But both definitions must be the same.
     typedef typename Function<F>::Result Result;
     GTEST_COMPILE_ASSERT_(
-        !internal::is_reference<Result>::value,
+        !is_reference<Result>::value,
         use_ReturnRef_instead_of_Return_to_return_a_reference);
-    return Action<F>(new Impl<F>(value_));
+    return Action<F>(new Impl<R, F>(value_));
   }
 
  private:
   // Implements the Return(x) action for a particular function type F.
-  template <typename F>
+  template <typename R_, typename F>
   class Impl : public ActionInterface<F> {
    public:
     typedef typename Function<F>::Result Result;
@@ -525,20 +533,45 @@ class ReturnAction {
     // 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(R value)
-        : value_(::testing::internal::ImplicitCast_<Result>(value)) {}
+    explicit Impl(const linked_ptr<R>& value)
+        : value_(ImplicitCast_<Result>(*value)) {}
 
     virtual Result Perform(const ArgumentTuple&) { return value_; }
 
    private:
-    GTEST_COMPILE_ASSERT_(!internal::is_reference<Result>::value,
+    GTEST_COMPILE_ASSERT_(!is_reference<Result>::value,
                           Result_cannot_be_a_reference_type);
     Result value_;
 
     GTEST_DISALLOW_ASSIGN_(Impl);
   };
 
-  R value_;
+  // 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 linked_ptr<R>& wrapper)
+        : performed_(false), wrapper_(wrapper) {}
+
+    virtual Result Perform(const ArgumentTuple&) {
+      GTEST_CHECK_(!performed_)
+          << "A ByMove() action should only be performed once.";
+      performed_ = true;
+      return move(wrapper_->payload);
+    }
+
+   private:
+    bool performed_;
+    const linked_ptr<R> wrapper_;
+
+    GTEST_DISALLOW_ASSIGN_(Impl);
+  };
+
+  const linked_ptr<R> value_;
 
   GTEST_DISALLOW_ASSIGN_(ReturnAction);
 };
@@ -977,7 +1010,7 @@ Action<To>::Action(const Action<From>& from)
 // will trigger a compiler error about using array as initializer.
 template <typename R>
 internal::ReturnAction<R> Return(R value) {
-  return internal::ReturnAction<R>(value);
+  return internal::ReturnAction<R>(internal::move(value));
 }
 
 // Creates an action that returns NULL.
@@ -1004,6 +1037,15 @@ 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>(internal::move(x));
+}
+
 // Creates an action that does the default action for the give mock function.
 inline internal::DoDefaultAction DoDefault() {
   return internal::DoDefaultAction();

include/gmock/gmock-spec-builders.h

@@ -1302,15 +1302,12 @@ template <typename T>
 class ReferenceOrValueWrapper {
  public:
   // Constructs a wrapper from the given value/reference.
-  explicit ReferenceOrValueWrapper(T value)
-      : value_(GTEST_MOVE_(value)) {}
+  explicit ReferenceOrValueWrapper(T value) : value_(move(value)) {}
 
   // Unwraps and returns the underlying value/reference, exactly as
   // originally passed. The behavior of calling this more than once on
   // the same object is unspecified.
-  T Unwrap() {
-    return GTEST_MOVE_(value_);
-  }
+  T Unwrap() { return move(value_); }
 
   // Provides nondestructive access to the underlying value/reference.
   // Always returns a const reference (more precisely,
@@ -1407,8 +1404,7 @@ class ActionResultHolder : public UntypedActionResultHolderBase {
  private:
   typedef ReferenceOrValueWrapper<T> Wrapper;
 
-  explicit ActionResultHolder(Wrapper result)
-      : result_(GTEST_MOVE_(result)) {}
+  explicit ActionResultHolder(Wrapper result) : result_(move(result)) {}
 
   Wrapper result_;
 

test/gmock-actions_test.cc

@@ -57,6 +57,7 @@ using testing::_;
 using testing::Action;
 using testing::ActionInterface;
 using testing::Assign;
+using testing::ByMove;
 using testing::ByRef;
 using testing::DefaultValue;
 using testing::DoDefault;
@@ -638,6 +639,7 @@ class MockClass {
   MOCK_METHOD0(Foo, MyClass());
 #if GTEST_HAS_STD_UNIQUE_PTR_
   MOCK_METHOD0(MakeUnique, std::unique_ptr<int>());
+  MOCK_METHOD0(MakeUniqueBase, std::unique_ptr<Base>());
   MOCK_METHOD0(MakeVectorUnique, std::vector<std::unique_ptr<int>>());
 #endif
 
@@ -1285,7 +1287,42 @@ std::vector<std::unique_ptr<int>> VectorUniquePtrSource() {
   return out;
 }
 
-TEST(MockMethodTest, CanReturnMoveOnlyValue) {
+TEST(MockMethodTest, CanReturnMoveOnlyValue_Return) {
+  MockClass mock;
+  std::unique_ptr<int> i(new int(19));
+  EXPECT_CALL(mock, MakeUnique()).WillOnce(Return(ByMove(std::move(i))));
+  EXPECT_CALL(mock, MakeVectorUnique())
+      .WillOnce(Return(ByMove(VectorUniquePtrSource())));
+  Derived* d = new Derived;
+  EXPECT_CALL(mock, MakeUniqueBase())
+      .WillOnce(Return(ByMove(std::unique_ptr<Derived>(d))));
+
+  std::unique_ptr<int> result1 = mock.MakeUnique();
+  EXPECT_EQ(19, *result1);
+
+  std::vector<std::unique_ptr<int>> vresult = mock.MakeVectorUnique();
+  EXPECT_EQ(1, vresult.size());
+  EXPECT_NE(nullptr, vresult[0]);
+  EXPECT_EQ(7, *vresult[0]);
+
+  std::unique_ptr<Base> result2 = mock.MakeUniqueBase();
+  EXPECT_EQ(d, result2.get());
+}
+
+TEST(MockMethodTest, CanReturnMoveOnlyValue_DoAllReturn) {
+  testing::MockFunction<void()> mock_function;
+  MockClass mock;
+  std::unique_ptr<int> i(new int(19));
+  EXPECT_CALL(mock_function, Call());
+  EXPECT_CALL(mock, MakeUnique()).WillOnce(DoAll(
+      InvokeWithoutArgs(&mock_function, &testing::MockFunction<void()>::Call),
+      Return(ByMove(std::move(i)))));
+
+  std::unique_ptr<int> result1 = mock.MakeUnique();
+  EXPECT_EQ(19, *result1);
+}
+
+TEST(MockMethodTest, CanReturnMoveOnlyValue_Invoke) {
   MockClass mock;
 
   // Check default value
@@ -1294,8 +1331,7 @@ TEST(MockMethodTest, CanReturnMoveOnlyValue) {
   });
   EXPECT_EQ(42, *mock.MakeUnique());
 
-  EXPECT_CALL(mock, MakeUnique())
-      .WillRepeatedly(Invoke(UniquePtrSource));
+  EXPECT_CALL(mock, MakeUnique()).WillRepeatedly(Invoke(UniquePtrSource));
   EXPECT_CALL(mock, MakeVectorUnique())
       .WillRepeatedly(Invoke(VectorUniquePtrSource));
   std::unique_ptr<int> result1 = mock.MakeUnique();