code: protected static void failIfEqual(@Nullable String customErrorMessage, @Nullable Description descriptionOfActual,
                                      @Nullable Object actual, @Nullable Object other) {
      if (!areEqual(actual, other)) {
        return;
      }
      failWithMessage(customErrorMessage);
      fail(format(descriptionOfActual, unexpectedEqual(actual, other)));
    }
docs: Throws an {@code AssertionError} if the given objects are equal.
  
  @param customErrorMessage  any custom error message. This message will replace the default one only if it (the
  custom message) is not {@code null}.
  @param descriptionOfActual the description of the actual value.
  @param actual              the actual object.
  @param other               the object to compare to.
  @throws AssertionError if the given objects are equal.
  @since 1.2