* $patch = file_get_contents('example.patch'); * $diff = new Text_Diff('string', array($patch)); * $renderer = new Text_Diff_Renderer_inline(); * echo $renderer->render($diff); * * * Copyright 2005 Örjan Persson * 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 * @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 $edits; } } * @package Text_Diff */ class Text_Diff_Engine_xdiff { /** */ function diff($from_lines, $to_lines) { array_walk($from_lines, array('Text_Diff', 'trimNewlines')); array_walk($to_lines, array('Text_Diff', 'trimNewlines')); /* Convert the two input arrays into strings for xdiff processing. */ $from_string = implode("\n", $from_lines); $to_string = implode("\n", $to_lines); /* Diff the two strings and convert the result to an array. */ $diff = xdiff_string_diff($from_string, $to_string, count($to_lines)); $diff = explode("\n", $diff); /* Walk through the diff one line at a time. We build the $edits * array of diff operations by reading the first character of the * xdiff output (which is in the "unified diff" format). * * Note that we don't have enough information to detect "changed" * lines using this approach, so we can't add Text_Diff_Op_changed * instances to the $edits array. The result is still perfectly * valid, albeit a little less descriptive and efficient. */ $edits = array(); foreach ($diff as $line) { if (!strlen($line)) { continue; } switch ($line[0]) { case ' ': $edits[] = &new Text_Diff_Op_copy(array(substr($line, 1))); break; case '+': $edits[] = &new Text_Diff_Op_add(array(substr($line, 1))); break; case '-': $edits[] = &new Text_Diff_Op_delete(array(substr($line, 1))); break; } } return $edits; } }