+ − <?php
+ − /**
+ − * Class used internally by Diff to actually compute the diffs. This class
+ − * uses the xdiff PECL package (http://pecl.php.net/package/xdiff) to compute
+ − * the differences between the two input arrays.
+ − *
+ − * @author Jon Parise <jon@horde.org>
+ − * @package Text_Diff
+ − *
+ − * @access private
+ − */
+ − 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 $line) {
+ − switch ($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;
+ − }
+ −
+ − }