angelovcom.net

string.php (8354B)

---

 <?php
 /**
  * Parses unified or context diffs output from eg. the diff utility.
  *
  * Example:
  * <code>
  * $patch = file_get_contents('example.patch');
  * $diff = new Text_Diff('string', array($patch));
  * $renderer = new Text_Diff_Renderer_inline();
  * echo $renderer->render($diff);
  * </code>
  *
  * Copyright 2005 Örjan Persson <o@42mm.org>
  * Copyright 2005-2010 The Horde Project (http://www.horde.org/)
  *
  * See the enclosed file COPYING for license information (LGPL). If you did
  * not receive this file, see http://opensource.org/licenses/lgpl-license.php.
  *
  * @author  Örjan Persson <o@42mm.org>
  * @package Text_Diff
  * @since   0.2.0
  */
 class Text_Diff_Engine_string {
 
     /**
      * Parses a unified or context diff.
      *
      * First param contains the whole diff and the second can be used to force
      * a specific diff type. If the second parameter is 'autodetect', the
      * diff will be examined to find out which type of diff this is.
      *
      * @param string $diff  The diff content.
      * @param string $mode  The diff mode of the content in $diff. One of
      *                      'context', 'unified', or 'autodetect'.
      *
      * @return array  List of all diff operations.
      */
     function diff($diff, $mode = 'autodetect')
     {
         // Detect line breaks.
         $lnbr = "\n";
         if (strpos($diff, "\r\n") !== false) {
             $lnbr = "\r\n";
         } elseif (strpos($diff, "\r") !== false) {
             $lnbr = "\r";
         }
 
         // Make sure we have a line break at the EOF.
         if (substr($diff, -strlen($lnbr)) != $lnbr) {
             $diff .= $lnbr;
         }
 
         if ($mode != 'autodetect' && $mode != 'context' && $mode != 'unified') {
             return PEAR::raiseError('Type of diff is unsupported');
         }
 
         if ($mode == 'autodetect') {
             $context = strpos($diff, '***');
             $unified = strpos($diff, '---');
             if ($context === $unified) {
                 return PEAR::raiseError('Type of diff could not be detected');
             } elseif ($context === false || $unified === false) {
                 $mode = $context !== false ? 'context' : 'unified';
             } else {
                 $mode = $context < $unified ? 'context' : 'unified';
             }
         }
 
         // Split by new line and remove the diff header, if there is one.
         $diff = explode($lnbr, $diff);
         if (($mode == 'context' && strpos($diff[0], '***') === 0) ||
             ($mode == 'unified' && strpos($diff[0], '---') === 0)) {
             array_shift($diff);
             array_shift($diff);
         }
 
         if ($mode == 'context') {
             return $this->parseContextDiff($diff);
         } else {
             return $this->parseUnifiedDiff($diff);
         }
     }
 
     /**
      * Parses an array containing the unified diff.
      *
      * @param array $diff  Array of lines.
      *
      * @return array  List of all diff operations.
      */
     function parseUnifiedDiff($diff)
     {
         $edits = array();
         $end = count($diff) - 1;
         for ($i = 0; $i < $end;) {
             $diff1 = array();
             switch (substr($diff[$i], 0, 1)) {
             case ' ':
                 do {
                     $diff1[] = substr($diff[$i], 1);
                 } while (++$i < $end && substr($diff[$i], 0, 1) == ' ');
                 $edits[] = new Text_Diff_Op_copy($diff1);
                 break;
 
             case '+':
                 // get all new lines
                 do {
                     $diff1[] = substr($diff[$i], 1);
                 } while (++$i < $end && substr($diff[$i], 0, 1) == '+');
                 $edits[] = new Text_Diff_Op_add($diff1);
                 break;
 
             case '-':
                 // get changed or removed lines
                 $diff2 = array();
                 do {
                     $diff1[] = substr($diff[$i], 1);
                 } while (++$i < $end && substr($diff[$i], 0, 1) == '-');
 
                 while ($i < $end && substr($diff[$i], 0, 1) == '+') {
                     $diff2[] = substr($diff[$i++], 1);
                 }
                 if (count($diff2) == 0) {
                     $edits[] = new Text_Diff_Op_delete($diff1);
                 } else {
                     $edits[] = new Text_Diff_Op_change($diff1, $diff2);
                 }
                 break;
 
             default:
                 $i++;
                 break;
             }
         }
 
         return $edits;
     }
 
     /**
      * Parses an array containing the context diff.
      *
      * @param array $diff  Array of lines.
      *
      * @return array  List of all diff operations.
      */
     function parseContextDiff(&$diff)
     {
         $edits = array();
         $i = $max_i = $j = $max_j = 0;
         $end = count($diff) - 1;
         while ($i < $end && $j < $end) {
             while ($i >= $max_i && $j >= $max_j) {
                 // Find the boundaries of the diff output of the two files
                 for ($i = $j;
                      $i < $end && substr($diff[$i], 0, 3) == '***';
                      $i++);
                 for ($max_i = $i;
                      $max_i < $end && substr($diff[$max_i], 0, 3) != '---';
                      $max_i++);
                 for ($j = $max_i;
                      $j < $end && substr($diff[$j], 0, 3) == '---';
                      $j++);
                 for ($max_j = $j;
                      $max_j < $end && substr($diff[$max_j], 0, 3) != '***';
                      $max_j++);
             }
 
             // find what hasn't been changed
             $array = array();
             while ($i < $max_i &&
                    $j < $max_j &&
                    strcmp($diff[$i], $diff[$j]) == 0) {
                 $array[] = substr($diff[$i], 2);
                 $i++;
                 $j++;
             }
 
             while ($i < $max_i && ($max_j-$j) <= 1) {
                 if ($diff[$i] != '' && substr($diff[$i], 0, 1) != ' ') {
                     break;
                 }
                 $array[] = substr($diff[$i++], 2);
             }
 
             while ($j < $max_j && ($max_i-$i) <= 1) {
                 if ($diff[$j] != '' && substr($diff[$j], 0, 1) != ' ') {
                     break;
                 }
                 $array[] = substr($diff[$j++], 2);
             }
             if (count($array) > 0) {
                 $edits[] = new Text_Diff_Op_copy($array);
             }
 
             if ($i < $max_i) {
                 $diff1 = array();
                 switch (substr($diff[$i], 0, 1)) {
                 case '!':
                     $diff2 = array();
                     do {
                         $diff1[] = substr($diff[$i], 2);
                         if ($j < $max_j && substr($diff[$j], 0, 1) == '!') {
                             $diff2[] = substr($diff[$j++], 2);
                         }
                     } while (++$i < $max_i && substr($diff[$i], 0, 1) == '!');
                     $edits[] = new Text_Diff_Op_change($diff1, $diff2);
                     break;
 
                 case '+':
                     do {
                         $diff1[] = substr($diff[$i], 2);
                     } while (++$i < $max_i && substr($diff[$i], 0, 1) == '+');
                     $edits[] = new Text_Diff_Op_add($diff1);
                     break;
 
                 case '-':
                     do {
                         $diff1[] = substr($diff[$i], 2);
                     } while (++$i < $max_i && substr($diff[$i], 0, 1) == '-');
                     $edits[] = new Text_Diff_Op_delete($diff1);
                     break;
                 }
             }
 
             if ($j < $max_j) {
                 $diff2 = array();
                 switch (substr($diff[$j], 0, 1)) {
                 case '+':
                     do {
                         $diff2[] = substr($diff[$j++], 2);
                     } while ($j < $max_j && substr($diff[$j], 0, 1) == '+');
                     $edits[] = new Text_Diff_Op_add($diff2);
                     break;
 
                 case '-':
                     do {
                         $diff2[] = substr($diff[$j++], 2);
                     } while ($j < $max_j && substr($diff[$j], 0, 1) == '-');
                     $edits[] = new Text_Diff_Op_delete($diff2);
                     break;
                 }
             }
         }
 
         return $edits;
     }
 
 }