"JIT stack limit exhausted" error encountered for certain styles

[trepmal]

Here's my CSS, reduced/simplified from a real-world example: https://gist.github.com/trepmal/edf83dbd0d10b949b353c4b88fe20eea . The key elements being the selector with escaped characters, and a certain minimum amount of styles to follow.

When run through the minifier, nothing is returned:

use tubalmartin\CssMin\Minifier as CSSmin;

$css = file_get_contents( 'test.css' );

$minifier = new CSSmin;
$min = $minifier->run( $css );

// $min is empty

There "JIT stack limit exhausted" error comes from

YUI-CSS-compressor-PHP-port/src/Minifier.php

Lines 322 to 327 in 3cbf557

	// Process strings so their content doesn't get accidentally minified
	$css = preg_replace_callback(
	'/(?:"(?:[^\\\\"]|\\\\.|\\\\)*")|'."(?:'(?:[^\\\\']|\\\\.|\\\\)*')/S",
	array($this, 'processStringsCallback'),
	$css
	);

Which can be tested directly:

$min_test = preg_replace_callback(
	'/(?:"(?:[^\\\\"]|\\\\.|\\\\)*")|'."(?:'(?:[^\\\\']|\\\\.|\\\\)*')/S",
	function($i) { return $i; },
	$css
);

if ( preg_last_error() ) {
	echo preg_last_error_msg() . PHP_EOL;
}