assertEquals("Incorrect function.", msgs[2]);
    }

    @Test
    @DisplayName("Messages: accessing invalid index throws ArrayIndexOutOfBoundsException")
    void messagesOutOfBoundsThrows() {
        // Arrange
        String[] msgs = DosError.DOS_ERROR_MESSAGES;

        // Act & Assert: negative index
        assertThrows(ArrayIndexOutOfBoundsException.class, () -> {