public static void checkTrue(boolean expression, String errorMessage) {
        if (!expression) {
            throw new IllegalArgumentException(errorMessage);
        }
    }
@Test
    public void test_checkTrue_whenFalse() {
        String errorMessage = "foobar";
        try {
            checkTrue(false, errorMessage);
            fail();
        } catch (IllegalArgumentException e) {
            assertSame(errorMessage, e.getMessage());
        }
    }