TestingExceptionsWithMessage

Test_UserScore_GetValue.java

@Test
    public void GetScore_GetForNotExistingUser_ThrowException() {
        final UserScoreRepository userScoreRepositoryStub = Make_FakeUserScoreRepository();
        final UserScoreService userScore = new UserScoreService(userScoreRepositoryStub);
        final User fakeUser = null;

        try {
            final int userPoints = userScore.get(fakeUser);
        } catch (IllegalArgumentException e) {
            final String errorMessage = "User Is null";
            assertEquals(errorMessage, e.getMessage());
        }
    }