Google Mock一个返回空值但接受std::unique_ptr的方法

#include <gmock/gmock.h>
#include <memory>

class MyClass {
public:
    virtual ~MyClass() {}
    virtual void DoSomething(std::unique_ptr<int> ptr) = 0;
};

class MockMyClass : public MyClass {
public:
    MOCK_METHOD(void, DoSomething, (std::unique_ptr<int> ptr), (override));
};

TEST(MyClassTest, TestDoSomething) {
    MockMyClass mock;
    std::unique_ptr<int> ptr(new int(42));

    // 设置EXPECT_CALL，模拟DoSomething方法，并断言传入的std::unique_ptr为nullptr
    EXPECT_CALL(mock, DoSomething(testing::IsNull()));

    mock.DoSomething(std::move(ptr));
}

int main(int argc, char* argv[]) {
    testing::InitGoogleMock(&argc, argv);
    return RUN_ALL_TESTS();
}