"/[]/" breaks syntax highlighting

[roblourens]

Can repro in VS Code and Atom.

string.regexp.character-class.php never ends.

[hultberg]

Can reproduce in atom 1.19.

[50Wliu]

I mean, this is technically correct. You can't have an empty character class. []] is interpreted as "match any of the following: ]". Tempted to close as wontfix.

http://php.net/manual/en/regexp.reference.character-classes.php (emphasis mine)

An opening square bracket introduces a character class, terminated by a closing square bracket. A closing square bracket on its own is not special.

[roblourens]

If the string is necessarily a regex, I guess that's the right call. But it could just be a string that happens to have those 4 characters, right? This would be valid PHP, and also break the coloring of the whole file:

<?php

$x = "/[]/";
echo $x;

// ...

Could the pattern terminate at line end?

[50Wliu]

Hmm...I was under the impression that "/.../" would always be a regex. I'll take a look to see if there's a simple fix, but generally the regexes for the regex are quite unforgiving :(.

[Ingramz]

@50Wliu to add to that, regex delimiters are not just limited to /.