code: protected static void failIfSame(@Nullable String customErrorMessage, @Nullable Description descriptionOfActual,
                                     @Nullable Object actual, @Nullable Object other) {
      if (actual != other) {
        return;
      }
      failWithMessage(customErrorMessage);
      fail(descriptionOfActual, array("given objects are same:", inBrackets(actual)));
    }
docs: Throws an {@code AssertionError} if the given objects are the same.
  
  @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 the same.
  @since 1.2