I am studying in the gmock. Now Im trying to mock the class named "task", like this:
class MockTask : public Task
{
public:
MOCK_METHOD3(Execute, bool(std::set<std::string> &setDeviceIDs, int timeout, PACKET_DATA *Data));
};
And I want to save the struct pdata when the task.excute is called, so that I can validate the pdata->member. This is my code:
PAKET_DATA data;
EXPECT_CALL(task, Execute(testing::_, testing::_, testing::_))
.WillOnce(testing::saveArg<2>(&data));
ASSERT_EQ(data->resultcode, 0);
Is that correct? And what is the difference of saveArg and saveArgPointee?
As you can read in gmock doc:
SaveArg(pointer) Save the N-th (0-based) argument to *pointer.
SaveArgPointee(pointer) Save the value pointed to by the N-th (0-based) argument to *pointer.
for your case, you should use SaveArgPointee
- as you want to save pointed data (PACKET_DATA *Data
) - not the pointer itself...
Look at this example:
struct SomeData { int a; };
class ISomeClass
{
public:
virtual ~ISomeClass() = default;
virtual void foo(SomeData*) = 0;
};
void someFunction(ISomeClass& a)
{
SomeData b{1};
a.foo(&b);
}
class SomeMock : public ISomeClass
{
public:
MOCK_METHOD1(foo, void(SomeData*));
};
To test someFunction
you need to check pointee that is being passed to foo
:
TEST(TestSomeFoo, shallPassOne)
{
SomeData actualData{};
SomeMock aMock;
EXPECT_CALL(aMock, foo(_)).WillOnce(::testing::SaveArgPointee<0>(&actualData));
someFunction(aMock);
ASSERT_EQ(1, actualData.a);
}
If you used SaveArg
- you would just store pointer to local variable that no longer exists:
TEST(TestSomeFoo, shallPassOne_DanglingPointer)
{
SomeData* actualData;
SomeMock aMock;
EXPECT_CALL(aMock, foo(_)).WillOnce(::testing::SaveArg<0>(&actualData));
someFunction(aMock);
ASSERT_EQ(1, actualData->a);
}