public void endsWith(@Nullable String string) {
    checkNotNull(string);
    if (actual == null) {
      failWithActual("expected a string that ends with", string);
    } else if (!actual.endsWith(string)) {
      failWithActual("expected to end with", string);
    }
  }
@Test
  public void stringEndsWithFail() {
    expectFailureWhenTestingThat("abc").endsWith("ab");
    assertFailureValue("expected to end with", "ab");
  }