}

    @ParameterizedTest
    @ValueSource(ints = { -1, Integer.MIN_VALUE, Integer.MAX_VALUE })
    @DisplayName("Unknown codes: lookup returns empty Optional")
    void lookup_returns_empty_for_unknown_codes(int unknownCode) {
        // Invalid inputs: codes not present should yield no message
        // Guard to ensure test remains valid if constants change in future
        for (int c : WinError.WINERR_CODES) {