From 6a046e33e9f140a31f7b8543a5485405ab70cf15 Mon Sep 17 00:00:00 2001
From: Michele Locati <michele@locati.it>
Date: Fri, 2 Sep 2016 10:55:07 +0200
Subject: [PATCH] Use strpos (much faster than preg_match) to determine if a
 char is a white space

White space characters are defined by the PCRELib as:
- LF (dec 10 = hex \x0a = char "\n")
- HT (dec 9 = hex \x09 = char "\t")
- VT (dec 11 = hex \x0b = char "\v")
- FF (dec 12 = hex \x0c = char "\f")
- CR (dec 13 = hex \x0d = char "\r")
- space (dec 32 = hex \x20 = char " ")

Reference:
https://github.com/php/php-src/blob/master/ext/pcre/pcrelib/doc/pcre.txt#L5203-L5204
---
 lib/Less/Parser.php | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/Less/Parser.php b/lib/Less/Parser.php
index 1c65f982..44ff885c 100644
--- a/lib/Less/Parser.php
+++ b/lib/Less/Parser.php
@@ -664,9 +664,15 @@ private function forget(){
 		array_pop($this->saveStack);
 	}
 
-
+	/**
+	 * Determine if the character at the specified offset from the current position is a white space.
+	 *
+	 * @param int $offset
+	 *
+	 * @return bool
+	 */
 	private function isWhitespace($offset = 0) {
-		return preg_match('/\s/',$this->input[ $this->pos + $offset]);
+		return strpos(" \t\n\r\v\f", $this->input[$this->pos + $offset]) !== false;
 	}
 
 	/**