3 [**Actions**](../gmock_for_dummies.md#actions-what-should-it-do) specify what a
4 mock function should do when invoked. This page lists the built-in actions
5 provided by GoogleTest. All actions are defined in the `::testing` namespace.
9 | Action | Description |
10 | :-------------------------------- | :-------------------------------------------- |
11 | `Return()` | Return from a `void` mock function. |
12 | `Return(value)` | Return `value`. If the type of `value` is different to the mock function's return type, `value` is converted to the latter type <i>at the time the expectation is set</i>, not when the action is executed. |
13 | `ReturnArg<N>()` | Return the `N`-th (0-based) argument. |
14 | `ReturnNew<T>(a1, ..., ak)` | Return `new T(a1, ..., ak)`; a different object is created each time. |
15 | `ReturnNull()` | Return a null pointer. |
16 | `ReturnPointee(ptr)` | Return the value pointed to by `ptr`. |
17 | `ReturnRef(variable)` | Return a reference to `variable`. |
18 | `ReturnRefOfCopy(value)` | Return a reference to a copy of `value`; the copy lives as long as the action. |
19 | `ReturnRoundRobin({a1, ..., ak})` | Each call will return the next `ai` in the list, starting at the beginning when the end of the list is reached. |
23 | Action | Description |
24 | :--------------------------------- | :-------------------------------------- |
25 | `Assign(&variable, value)` | Assign `value` to variable. |
26 | `DeleteArg<N>()` | Delete the `N`-th (0-based) argument, which must be a pointer. |
27 | `SaveArg<N>(pointer)` | Save the `N`-th (0-based) argument to `*pointer`. |
28 | `SaveArgPointee<N>(pointer)` | Save the value pointed to by the `N`-th (0-based) argument to `*pointer`. |
29 | `SetArgReferee<N>(value)` | Assign `value` to the variable referenced by the `N`-th (0-based) argument. |
30 | `SetArgPointee<N>(value)` | Assign `value` to the variable pointed by the `N`-th (0-based) argument. |
31 | `SetArgumentPointee<N>(value)` | Same as `SetArgPointee<N>(value)`. Deprecated. Will be removed in v1.7.0. |
32 | `SetArrayArgument<N>(first, last)` | Copies the elements in source range [`first`, `last`) to the array pointed to by the `N`-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. |
33 | `SetErrnoAndReturn(error, value)` | Set `errno` to `error` and return `value`. |
34 | `Throw(exception)` | Throws the given exception, which can be any copyable value. Available since v1.1.0. |
36 ## Using a Function, Functor, or Lambda as an Action
38 In the following, by "callable" we mean a free function, `std::function`,
41 | Action | Description |
42 | :---------------------------------- | :------------------------------------- |
43 | `f` | Invoke `f` with the arguments passed to the mock function, where `f` is a callable. |
44 | `Invoke(f)` | Invoke `f` with the arguments passed to the mock function, where `f` can be a global/static function or a functor. |
45 | `Invoke(object_pointer, &class::method)` | Invoke the method on the object with the arguments passed to the mock function. |
46 | `InvokeWithoutArgs(f)` | Invoke `f`, which can be a global/static function or a functor. `f` must take no arguments. |
47 | `InvokeWithoutArgs(object_pointer, &class::method)` | Invoke the method on the object, which takes no arguments. |
48 | `InvokeArgument<N>(arg1, arg2, ..., argk)` | Invoke the mock function's `N`-th (0-based) argument, which must be a function or a functor, with the `k` arguments. |
50 The return value of the invoked function is used as the return value of the
53 When defining a callable to be used with `Invoke*()`, you can declare any unused
54 parameters as `Unused`:
57 using ::testing::Invoke;
58 double Distance(Unused, double x, double y) { return sqrt(x*x + y*y); }
60 EXPECT_CALL(mock, Foo("Hi", _, _)).WillOnce(Invoke(Distance));
63 `Invoke(callback)` and `InvokeWithoutArgs(callback)` take ownership of
64 `callback`, which must be permanent. The type of `callback` must be a base
65 callback type instead of a derived one, e.g.
68 BlockingClosure* done = new BlockingClosure;
69 ... Invoke(done) ...; // This won't compile!
71 Closure* done2 = new BlockingClosure;
72 ... Invoke(done2) ...; // This works.
75 In `InvokeArgument<N>(...)`, if an argument needs to be passed by reference,
76 wrap it inside `std::ref()`. For example,
79 using ::testing::InvokeArgument;
81 InvokeArgument<2>(5, string("Hi"), std::ref(foo))
84 calls the mock function's #2 argument, passing to it `5` and `string("Hi")` by
85 value, and `foo` by reference.
89 | Action | Description |
90 | :------------ | :----------------------------------------------------- |
91 | `DoDefault()` | Do the default action (specified by `ON_CALL()` or the built-in one). |
94 **Note:** due to technical reasons, `DoDefault()` cannot be used inside a
95 composite action - trying to do so will result in a run-time error.
99 | Action | Description |
100 | :----------------------------- | :------------------------------------------ |
101 | `DoAll(a1, a2, ..., an)` | Do all actions `a1` to `an` and return the result of `an` in each invocation. The first `n - 1` sub-actions must return void and will receive a readonly view of the arguments. |
102 | `IgnoreResult(a)` | Perform action `a` and ignore its result. `a` must not return void. |
103 | `WithArg<N>(a)` | Pass the `N`-th (0-based) argument of the mock function to action `a` and perform it. |
104 | `WithArgs<N1, N2, ..., Nk>(a)` | Pass the selected (0-based) arguments of the mock function to action `a` and perform it. |
105 | `WithoutArgs(a)` | Perform action `a` without any arguments. |
109 | Macro | Description |
110 | :--------------------------------- | :-------------------------------------- |
111 | `ACTION(Sum) { return arg0 + arg1; }` | Defines an action `Sum()` to return the sum of the mock function's argument #0 and #1. |
112 | `ACTION_P(Plus, n) { return arg0 + n; }` | Defines an action `Plus(n)` to return the sum of the mock function's argument #0 and `n`. |
113 | `ACTION_Pk(Foo, p1, ..., pk) { statements; }` | Defines a parameterized action `Foo(p1, ..., pk)` to execute the given `statements`. |
115 The `ACTION*` macros cannot be used inside a function or class.