I want to run a regex search from inside PhpStorm (could be any file manager though, Double/Total Commander handles regex searches just as well) to match php variables that are inside single quotes and therefore string interpolation won't work on them e.g. '$var'.
The content of the files would be something like this:
$var = 'Hello world!';
echo 'Lorem ipsum $var dolor sit amet'; // Match this.
echo "Lorem ipsum 'dolor sit amet $var consectetur' adipiscing elit"; // But not this.
echo "Lorem ipsum 'dolor sit amet \$var consectetur' adipiscing elit"; // Or this.
I want the regex search to match the first statement, but not the second or third.
I've tried '[\w ]+\$[\w]+[\w ]+' but that doesn't work because it matches all statements regardless of the double quotes or escaped dollar sign. (regex101).
This is just a regular regex search that I want to run on my repo to find buggy code.
What regex could I use for this?
(I don't need to get any text in between quotes, just php variables in between single quotes that aren't escaped.)
What you need is negative lookaround. In particular, negative lookahead, because in PHP you are not allowed to use no-fixed-length lookbehind:
'[\w ]+\$[\w]+[\w ]+'(?![\w$ ']*")
(?![\w$ ']*") means that the string that you want to match must not be followed by a ", with any number of character (the ones that you want to allow in a string) in the middle.
See also: http://www.regular-expressions.info/lookaround.html