* For readability, use /x in regexes. Removed the start and end slashes from the...

* Broke up several regexes and added comments, so that humans might be able to understand them.
* Tested md5(minify(jquery.js)) as before. Checked speed, it's the same.

diff --git a/includes/libs/JavaScriptDistiller.php b/includes/libs/JavaScriptDistiller.php
index b377ac5..1c44e6b 100644 (file)
--- a/includes/libs/JavaScriptDistiller.php
+++ b/includes/libs/JavaScriptDistiller.php
@@ -31,13 +31,13 @@ class JavaScriptDistiller {
        public static function stripHorizontalSpace( $script ) {
                $parser = self::createParser();
                // Collapse horizontal whitespaces between variable names into a single space
-               $parser->add( '/(\b|\$)[ \t]+(\b|\$)/', '$2 $3' );
+               $parser->add( '(\b|\$) [ \t]+ (\b|\$)', '$2 $3' );
                // Collapse horizontal whitespaces between unary operators into a single space
-               $parser->add( '/([+\-])[ \t]+([+\-])/', '$2 $3' );
+               $parser->add( '([+\-]) [ \t]+ ([+\-])', '$2 $3' );
                // Remove all remaining un-protected horizontal whitespace
-               $parser->add( '/[ \t]+/');
+               $parser->add( '[ \t]+');
                // Collapse multiple vertical whitespaces with some horizontal spaces between them
-               $parser->add( '/[\r\n]+[ \t]*[\r\n]+/', "\n" );
+               $parser->add( '[\r\n]+ [ \t]* [\r\n]+', "\n" );
                // Execute and return
                return $parser->exec($script);
        }
@@ -45,16 +45,16 @@ class JavaScriptDistiller {
        public static function stripVerticalSpace( $script ) {
                $parser = self::createParser();
                // Collapse whitespaces between and after a ){ pair (function definitions)
-               $parser->add( '/\)\s+\{\s+/', '){' );
+               $parser->add( '\) \s+ \{ \s+', '){' );
                // Collapse whitespaces between and after a ({ pair (JSON argument)
-               $parser->add( '/\(\s+\{\s+/', '({' );
+               $parser->add( '\( \s+ \{ \s+', '({' );
                // Collapse whitespaces between a parenthesis and a period (call chaining)
-               $parser->add( '/\)\s+\./', ').');
+               $parser->add( '\) \s+ \.', ').');
                // Collapse vertical whitespaces which come directly after a semicolon or a comma
-               $parser->add( '/([;,])\s+/', '$2' );
+               $parser->add( '( [;,] ) \s+', '$2' );
                // Collapse whitespaces between multiple parenthesis/brackets of similar direction
-               $parser->add( '/([\)\}])\s+([\)\}])/', '$2$3' );
-               $parser->add( '/([\(\{])\\s+([\(\{])/', '$2$3' );
+               $parser->add( '( [\)\}] ) \s+ ( [\)\}] )', '$2$3' );
+               $parser->add( '( [\(\{] ) \s+ ( [\(\{] )', '$2$3' );
                return $parser->exec( $script );
        }
 
@@ -77,15 +77,52 @@ class JavaScriptDistiller {
                // Protect strings. The original code had [^\'\\v] here, but that didn't armor multiline
                // strings correctly. This also armors multiline strings that don't have backslashes at the
                // end of the line (these are invalid), but that's fine because we're just armoring here.
-               $parser->add( '/\'([^\'\\\\]*(\\\\(.|[\r\n])[^\'\\\\]*)*)\'/', '$1' );
-               $parser->add( '/"([^"\\\\]*(\\\\(.|[\r\n])[^"\\\\]*)*)"/', '$1' );
+
+               // Single quotes
+               $parser->add( 
+                       '\' (' . // start quote
+                       '[^\'\\\\]*' . // a run of non-special characters
+                       '(' .
+                               '\\\\ ( . | [\r\n] )' . // a backslash followed by a character or line ending
+                               '[^\'\\\\]*' . // a run of non-special characters
+                       ')*' . // any number of the above
+                       ') \'', // end quote
+                       '$1' );
+
+               // Double quotes: same as above
+               $parser->add( '" ( [^"\\\\]* ( \\\\ ( . | [\r\n] ) [^"\\\\]* )* ) "', '$1' );
+
                // Protect regular expressions
-               $parser->add( '/[ \t]+((\/[^\r\n\*][^\/\r\n\\\\]*(\\\\.[^\/\r\n\\\\]*)*\/(i|g)*))/', '$1' );
-               $parser->add( '/([^\w\$\/\'"*)\?:](\/[^\r\n\*][^\/\r\n\\\\]*(\\\\.[^\/\r\n\\\\]*)*\/(i|g)*))/', '$1' );
-               // Remove comments
-               $parser->add( '/\/\*(.|[\r\n])*?\*\//' );
+               // Regular expression with whitespace before it
+               $parser->add(
+                       '[ \t]+ ( ( \/' . // whitespace then start slash
+                       '[^\r\n\*]' . // not a comment-start or line ending
+                       '[^\/\r\n\\\\]*' . // a sequence of non-special characters
+                       '(' . 
+                               '\\\\.' . // an escaped dot
+                               '[^\/\r\n\\\\]*' . // a sequence of non-special characters
+                       ')*' . // any number of the above
+                       '\/(i|g)*' . // pattern end, optional modifier
+                       ') )', 
+                       '$1' );
+               // Regular expression with an operator before it
+               $parser->add( 
+                       '( [^\w\$\/\'"*)\?:] (\/' . // certain kinds of punctuation and then start slash
+                       '[^\r\n\*]' . // not a comment-start or line ending
+                       '[^\/\r\n\\\\]*' . // a sequence of non-special characters
+                       '(' . 
+                               '\\\\.' . // an escaped dot
+                               '[^\/\r\n\\\\]*' . // a sequence of non-special characters
+                       ')*' . // any number of the above
+                       '\/(i|g)*)' . // pattern end, optional modifier
+                       ')',
+                       '$1' );
+
+               // C-style comment: use non-greedy repetition to find the end
+               $parser->add( '\/ \* ( . | [\r\n] )*? \* \/' );
+
                // Preserve the newline after a C++-style comment -- bug 27046
-               $parser->add( '/\/\/[^\r\n]*([\r\n])/', '$2' );
+               $parser->add( '\/ \/ [^\r\n]* ( [\r\n] )', '$2' );
                return $parser;
        }
 }
@@ -160,9 +197,9 @@ class ParseMaster {
                // simulate the _patterns.toSTring of Dean
                $regexp = '/';
                foreach ($this->_patterns as $reg) {
-                       $regexp .= '(' . substr($reg[self::EXPRESSION], 1, -1) . ')|';
+                       $regexp .= '(' . $reg[self::EXPRESSION] . ')|';
                }
-               $regexp = substr($regexp, 0, -1) . '/S';
+               $regexp = substr($regexp, 0, -1) . '/Sx';
                $regexp .= ($this->ignoreCase) ? 'i' : '';
 
                $string = $this->_escape($string, $this->escapeChar);