Smarty Forum Index Smarty
WARNING: All discussion is moving to https://reddit.com/r/smarty, please go there! This forum will be closing soon.

Improving trimwhitespaces output filter

 
This forum is locked: you cannot post, reply to, or edit topics.   This topic is locked: you cannot edit posts or make replies.    Smarty Forum Index -> Feature Requests
View previous topic :: View next topic  
Author Message
projekter
Smarty n00b


Joined: 15 Sep 2011
Posts: 1

PostPosted: Thu Sep 15, 2011 12:37 pm    Post subject: Improving trimwhitespaces output filter Reply with quote

The trimwhitespaces filter doesn't trim really all whitespaces that can be trimmed. I enhanced the function and also added two functions for css and javascript which can be used if smarty is also used to output stylesheet or code or if inline css/js is used.
So far, I didn't recognize any errors in the code that changes its meaning, but I appreciate comments. (I used camel case notation to differ from the current version.)
Notice that in the javascript trim function only one-line-cdata is possible, as described in the function comment. Other notations could also be implemented if someone wants to.
Code:
function smarty_outputfilter_TrimWhiteSpace($source, Smarty_Internal_Template $smarty)
{
   $store   = array();
   $_store  = $_offset = 0;
   // Unify Line-Breaks to \n
   $source  = preg_replace('#\xD#', '', $source);
   // capture Internet Explorer Conditional Comments
   if(preg_match_all('#<!--\[[^\]]+\]>.*?<!\[[^\]]+\]-->#is', $source,
                     $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER))
   {
      foreach($matches as $match)
      {
         $store[$_store] = $match[0][0];
         $_length        = strlen($match[0][0]);
         $replace        = '@!@SMARTY:' . $_store . ':SMARTY@!@';
         $source         = substr_replace($source, $replace,
                                          $match[0][1] - $_offset, $_length);
         $_offset       += $_length - strlen($replace);
         ++$_store;
      }
   }
   // Strip all HTML-Comments
   $source  = preg_replace('#<!--.*?-->#ms', '', $source);
   // capture html elements not to be messed with
   $_offset = 0;
   if(preg_match_all('#<(script|pre|textarea|style)[^>]*>(.*?)</\\1>#is', $source,
                     $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER))
   {
      foreach($matches as $match)
      {
         if((strtolower($match[1][0]) == 'script') &&
            (trim($match[2][0]) != ''))
         {
            $store[] = '<script type="text/javascript">' .
                       smarty_outputfilter_TrimWhiteSpaceJS($match[2][0],
                                                            $smarty) .

                       '</script>';
         }elseif((strtolower($match[1][0]) == 'style') &&
                 (trim($match[2][0]) != ''))
         {
            $store[] = '<style type="text/css">' .
                       smarty_outputfilter_TrimWhiteSpaceCSS($match[2][0],
                                                            $smarty) .

                       '</style>';
         }else{
            $store[] = $match[0][0];
         }
         $_length  = strlen($match[0][0]);
         $replace  = '@!@SMARTY:' . $_store . ':SMARTY@!@';
         $source   = substr_replace($source, $replace, $match[0][1] - $_offset,
                                    $_length);
         $_offset += $_length - strlen($replace);
         ++$_store;
      }
   }
   $expressions = array(
      // replace multiple spaces between tags by a single space
      // can't remove them entirely, becaue that might break poorly implemented CSS display:inline-block elements
      '#(:SMARTY@!@|>|\S)\s+(?=@!@SMARTY:|<|\S)#s' => '\1 \2',
      // remove spaces between attributes (but not in attribute values!)
      '#(([a-z0-9]\s*=\s*(["\'])[^\3]*?\3)|<[a-z0-9_]+)\s+([a-z/>])#is' => '\1 \4',
      // note: for some very weird reason trim() seems to remove spaces inside attributes.
      // maybe a \0 byte or something is interfering?
      '#^\s+<#s' => '<',
      '#>\s+$#s' => '>',
      '#\s*(/)?\s*>#s' => '\1>'
   );
   $source = preg_replace(array_keys($expressions), array_values($expressions),
                          $source);
   // capture html elements not to be messed with
   $_offset = 0;
   if(preg_match_all('#@!@SMARTY:([0-9]+):SMARTY@!@#is', $source, $matches,
                     PREG_OFFSET_CAPTURE | PREG_SET_ORDER))
   {
      foreach($matches as $match)
      {
         $_length = strlen($match[0][0]);
         $replace = $store[$match[1][0]];
         $source  = substr_replace($source, $replace, $match[0][1] + $_offset,
                                   $_length);
         $_offset += strlen($replace) - $_length;
         ++$_store;
      }
   }
   return $source;
}

function smarty_outputfilter_TrimWhiteSpaceCSS($source, Smarty_Internal_Template $smarty)
{
   $expressions = array(
      // No line breaks
      '#\xD|\xA#'              => '',
      // No CSS comment
      '#/\*.*?\*/#s'           => '',
      // No white spaces except from attribute values
      '#\s*(:|;|\{|\}|,)\s*#s' => '\1',
      // No multiple white spaces within attribute values
      '#\s+#'                  => ' '
   );
   $source = preg_replace(array_keys($expressions), array_values($expressions),
                         $source);
   return $source;
}

function smarty_outputfilter_TrimWhiteSpaceJS($source, Smarty_Internal_Template $smarty)
{
   $expressions = array(
      # capture CDATA. Only one-line-CDATA is possible, and only one START per line:
      # Allowed: // <![CDATA[ _____ ]]>
      # Allowed: // <![CDATA[
      #          // ]]>
      '#//.*?<!\[CDATA\[(.*?)]]>#i' => '@!@CDATA:\1:CDATA@!@',
      '#//.*?<!\[CDATA\[.*?#i'      => '@!@CDATA:',
      '#//.*?]]>.*?#i'              => ':CDATA@!@',
      // No JS comments
      '#/\*.*?\*/#s'                => '',
      '#//.*#'                      => '',
      // Restore CDATA
      '#@!@CDATA:#'                 => '/*<![CDATA[*/',
      '#:CDATA@!@#'                 => '/*]]>*/',
      // No line breaks
      '#\xD|\xA#'                   => '',
   );
   $source = preg_replace(array_keys($expressions), array_values($expressions),
                          $source);
   $store  = array();
   $_store = $_offset = 0;
   // strings
   $_offset = 0;
   if(preg_match_all('#(\'|")((.*?)(\\\\)*(\\\1)*)*\1#s', $source, $matches,
                     PREG_OFFSET_CAPTURE | PREG_SET_ORDER))
   {
      foreach($matches as $match)
      {
         $store[$_store] = $match[0][0];
         $_length        = strlen($match[0][0]);
         $replace        = '@!@SMARTY:' . $_store . ':SMARTY@!@';
         $source         = substr_replace($source, $replace,
                                          $match[0][1] - $_offset, $_length);
         $_offset       += $_length - strlen($replace);
         ++$_store;
      }
   }
   // trim whitespaces
   $source = preg_replace('#\s*([^a-zA-Z])\s*#', '\1', $source);
   // redo replacements
   $_offset = 0;
   if(preg_match_all('#@!@SMARTY:([0-9]+):SMARTY@!@#is', $source, $matches,
                     PREG_OFFSET_CAPTURE | PREG_SET_ORDER))
   {
      foreach($matches as $match)
      {
         $_length  = strlen($match[0][0]);
         $replace  = $store[$match[1][0]];
         $source   = substr_replace($source, $replace, $match[0][1] + $_offset,
                                    $_length);
         $_offset += strlen($replace) - $_length;
         ++$_store;
      }
   }
   return $source;
}
Back to top
View user's profile Send private message
Display posts from previous:   
This forum is locked: you cannot post, reply to, or edit topics.   This topic is locked: you cannot edit posts or make replies.    Smarty Forum Index -> Feature Requests All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group
Protected by Anti-Spam ACP