actual:
Currently an empty or non-existent end pattern will match against the unicode character � \uFFFF

this bug was caused by a partial fix of

• Unexpected highlighting behavior when end is not defined #66

7640bd6 didn't fix it, but instead just moved the bug along from matching undefined to matching �

expected:
after doing testing in TextMate 2.0
I can confirm that an empty or non-existent end pattern will match immediately

the fix is as simple as replacing '\uFFFF' with ''
pr #252