"WINERR_MESSAGES content differs");
    }

    @ParameterizedTest(name = "Known code {0} maps to message")
    @MethodSource("knownCodeMessagePairs")
    void lookup_returns_expected_message_for_known_codes(int code, String expectedMessage) {
        // Valid inputs: each known code must map to its documented message
        assertEquals(expectedMessage, lookupMessage(code).orElse(null));
    }