src/main/java/org/fest/assertions/Fail.java
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)));
  }
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)));
  }
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