assertEquals("FFFF", Hexdump.toHexString(-1, 4));
        assertEquals("FF", Hexdump.toHexString(-1, 2));
    }

    @Test
    @DisplayName("Should convert long to hex string with specified size")
    void testToHexStringLong() {
        // Test zero
        assertEquals("0000000000000000", Hexdump.toHexString(0L, 16));
        assertEquals("00000000", Hexdump.toHexString(0L, 8));
        assertEquals("0000", Hexdump.toHexString(0L, 4));