嵌套预期调用时，gtest EXPECT_CALL 不起作用

Question

Look at such code snippet:

class Foo {
 public:
  Foo() {
  }

  void invoke_init(const int i) {
    init(i);
  }

 private:
  void init(const int i) {
    std::cout << "init " << i << std::endl;
  }
};
    
class MockedFoo : public Foo {
 public:
  MOCK_METHOD(void, init, (const int));
};

TEST(Foo, TestInitCalled) {
  MockedFoo mock;
  mock.invoke_init(1);
  EXPECT_CALL(mock, init(1));
}

As expected, init() is called and i see corresponding output. But the test is failed. Why? What is wrong there?

Answer 1

Foo::init needs to be protected instead of private . It also needs to be virtual .

Without protected as its visibility attribute, it can't really be overridden in the inherited class. Without virtual, gmock can't do much with it either.

Instead of this:

 private:
  void init(const int i) {
    std::cout << "init " << i << std::endl;
  }

This:

 protected:
  virtual void init(const int i) {
    std::cout << "init " << i << std::endl;
  }