Avoid calling realpath on urls

lessc.inc.php

@@ -150,7 +150,7 @@ public function compileFile( $fname, $outFname = null ) {
 		$oldImport = $this->importDir;
 
 		$this->importDir = (array)$this->importDir;
-		$this->importDir[] = realpath( $pi['dirname'] ).'/';
+		$this->importDir[] = Less_Parser::AbsPath( $pi['dirname'] ).'/';
 
 		$this->allParsedFiles = array();
 		$this->addParsedFile( $fname );
@@ -271,6 +271,6 @@ public function allParsedFiles() {
 	}
 
 	protected function addParsedFile( $file ) {
-		$this->allParsedFiles[realpath( $file )] = filemtime( $file );
+		$this->allParsedFiles[Less_Parser::AbsPath( $file )] = filemtime( $file );
 	}
 }

lib/Less/Parser.php

@@ -352,7 +352,7 @@ public function parseFile( $filename, $uri_root = '', $returnRoot = false){
 
 
 		if( $filename ){
-			$filename = self::WinPath(realpath($filename));
+			$filename = self::AbsPath($filename, true);
 		}
 		$uri_root = self::WinPath($uri_root);
 
@@ -2660,6 +2660,18 @@ public static function WinPath($path){
 		return str_replace('\\', '/', $path);
 	}
 
+	public static function AbsPath($path, $winPath = false){
+		if (strpos($path, '//') !== false && preg_match('_^(https?:)?//\\w+(\\.\\w+)+/\\w+_', $path)) {
+			return $winPath ? '' : false;
+		} else {
+			$path = realpath($path);
+			if ($winPath) {
+				$path = self::WinPath($path);
+			}
+			return $path;
+		}
+	}
+
 	public function CacheEnabled(){
 		return (Less_Parser::$options['cache_method'] && (Less_Cache::$cache_dir || (Less_Parser::$options['cache_method'] == 'callback')));
 	}

lib/Less/Tree/Import.php

@@ -289,7 +289,7 @@ public function ParseImport( $full_path, $uri, $env ){
 	 */
 	private function Skip($path, $env){
 
-		$path = Less_Parser::winPath(realpath($path));
+		$path = Less_Parser::AbsPath($path, true);
 
 		if( $path && Less_Parser::FileParsed($path) ){