主要使用 mockito ArgumentCaptor
@Test
public void test_User_Follow_User() {
//预设 User
User user = new User();
user.setId(userId);
...
//模拟调用 findById 方法时返回值
when(userDao.findById(userId)).thenReturn(Optional.of(user));
ArgumentCaptor<FollowUser> followUserCaptor = ArgumentCaptor.forClass(FollowUser.class);
verify(followUserDao, times(1)).save(followUserCaptor.capture());
Assert.assertSame(user, followUserCaptor.getValue().getUser());
}
