@Test
public void getUserByIdThrowsExceptionWhenUserNotPresent() {

    // given
    var expectedMessage = String.format("User with ID '%s' not found!", USER_ID);
    // when / then
    assertThatThrownBy(() -> repoUserService.getUserById(USER_ID))
            .isInstanceOf(UserNotFoundException.class)
            .hasMessage(expectedMessage);
}