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844 lines
26 KiB
844 lines
26 KiB
<?php
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/**
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* Text_Diff
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*
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* General API for generating and formatting diffs - the differences between
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* two sequences of strings.
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*
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* The PHP diff code used in this package was originally written by Geoffrey
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* T. Dairiki and is used with his permission.
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*
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* $Horde: framework/Text_Diff/Diff.php,v 1.8 2004/10/13 09:30:20 jan Exp $
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*
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* @package Text_Diff
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* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
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*/
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class Text_Diff
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{
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/**
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* Array of changes.
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*
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* @var array $_edits
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*/
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public $_edits;
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/**
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* Computes diffs between sequences of strings.
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*
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* @param array $from_lines An array of strings. Typically these are
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* lines from a file.
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* @param array $to_lines An array of strings.
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* @param boolean $forceNative
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*/
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public function __construct($from_lines, $to_lines, $forceNative = false)
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{
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array_walk($from_lines, [$this, '_trimNewlines']);
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array_walk($to_lines, [$this, '_trimNewlines']);
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if (extension_loaded('xdiff') && ! $forceNative) {
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$engine = new Text_Diff_Engine_xdiff();
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} else {
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$engine = new Text_Diff_Engine_native();
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}
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$this->_edits = $engine->diff($from_lines, $to_lines);
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}
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/**
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* Returns the array of differences.
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*/
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public function getDiff()
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{
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return $this->_edits;
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}
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/**
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* Computes a reversed diff.
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*
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* Example:
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* <code>
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* $diff = new Text_Diff($lines1, $lines2);
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* $rev = $diff->reverse();
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* </code>
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*
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* @return Text_Diff A Diff object representing the inverse of the
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* original diff. Note that we purposely don't return a
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* reference here, since this essentially is a clone()
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* method.
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*/
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public function reverse()
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{
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if (version_compare(zend_version(), '2', '>')) {
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$rev = clone($obj);
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} else {
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$rev = $this;
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}
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$rev->_edits = [];
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foreach ($this->_edits as $edit) {
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$rev->_edits[] = $edit->reverse();
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}
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return $rev;
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}
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/**
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* Checks for an empty diff.
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*
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* @return boolean True if two sequences were identical.
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*/
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public function isEmpty()
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{
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foreach ($this->_edits as $edit) {
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if (! is_a($edit, 'Text_Diff_Op_copy')) {
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return false;
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}
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}
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return true;
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}
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/**
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* Computes the length of the Longest Common Subsequence (LCS).
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*
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* This is mostly for diagnostic purposed.
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*
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* @return int The length of the LCS.
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*/
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public function lcs()
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{
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$lcs = 0;
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foreach ($this->_edits as $edit) {
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if (is_a($edit, 'Text_Diff_Op_copy')) {
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$lcs += count($edit->orig);
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}
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}
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return $lcs;
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}
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/**
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* Gets the original set of lines.
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*
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* This reconstructs the $from_lines parameter passed to the constructor.
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*
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* @return array The original sequence of strings.
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*/
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public function getOriginal()
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{
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$lines = [];
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foreach ($this->_edits as $edit) {
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if ($edit->orig) {
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array_splice($lines, count($lines), 0, $edit->orig);
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}
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}
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return $lines;
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}
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/**
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* Gets the final set of lines.
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*
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* This reconstructs the $to_lines parameter passed to the constructor.
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*
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* @return array The sequence of strings.
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*/
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public function getFinal()
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{
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$lines = [];
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foreach ($this->_edits as $edit) {
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if ($edit->final) {
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array_splice($lines, count($lines), 0, $edit->final);
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}
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}
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return $lines;
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}
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/**
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* Removes trailing newlines from a line of text. This is meant to be used
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* with array_walk().
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*
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* @param string $line The line to trim.
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* @param integer $key The index of the line in the array. Not used.
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*/
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public function _trimNewlines(&$line, $key)
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{
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$line = str_replace(["\n", "\r", "\r\n"], '', $line);
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}
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/**
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* Checks a diff for validity.
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*
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* This is here only for debugging purposes.
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*/
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public function _check($from_lines, $to_lines)
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{
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if (serialize($from_lines) != serialize($this->getOriginal())) {
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trigger_error("Reconstructed original doesn't match", E_USER_ERROR);
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}
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if (serialize($to_lines) != serialize($this->getFinal())) {
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trigger_error("Reconstructed final doesn't match", E_USER_ERROR);
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}
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$rev = $this->reverse();
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if (serialize($to_lines) != serialize($rev->getOriginal())) {
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trigger_error("Reversed original doesn't match", E_USER_ERROR);
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}
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if (serialize($from_lines) != serialize($rev->getFinal())) {
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trigger_error("Reversed final doesn't match", E_USER_ERROR);
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}
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$prevtype = null;
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foreach ($this->_edits as $edit) {
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if ($prevtype == get_class($edit)) {
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trigger_error("Edit sequence is non-optimal", E_USER_ERROR);
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}
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$prevtype = get_class($edit);
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}
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return true;
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}
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}
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/**
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* $Horde: framework/Text_Diff/Diff.php,v 1.8 2004/10/13 09:30:20 jan Exp $
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*
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* @package Text_Diff
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* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
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*/
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class Text_MappedDiff extends Text_Diff
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{
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/**
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* Computes a diff between sequences of strings.
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*
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* This can be used to compute things like case-insensitve diffs, or diffs
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* which ignore changes in white-space.
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*
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* @param array $from_lines An array of strings.
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* @param array $to_lines An array of strings.
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* @param array $mapped_from_lines This array should have the same size
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* number of elements as $from_lines. The
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* elements in $mapped_from_lines and
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* $mapped_to_lines are what is actually
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* compared when computing the diff.
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* @param array $mapped_to_lines This array should have the same number
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* of elements as $to_lines.
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*/
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public function __construct(
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$from_lines,
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$to_lines,
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$mapped_from_lines,
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$mapped_to_lines
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) {
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// assert(count($from_lines) == count($mapped_from_lines));
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// assert(count($to_lines) == count($mapped_to_lines));
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parent::__construct($mapped_from_lines, $mapped_to_lines);
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$xi = $yi = 0;
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for ($i = 0, $count_edits = count($this->edits); $i < $count_edits; $i++) {
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$orig = &$this->edits[$i]->orig;
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if (is_array($orig)) {
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$orig = array_slice($from_lines, $xi, count($orig));
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$xi += count($orig);
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}
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$final = &$this->edits[$i]->final;
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if (is_array($final)) {
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$final = array_slice($to_lines, $yi, count($final));
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$yi += count($final);
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}
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}
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}
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}
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/**
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* Class used internally by Diff to actually compute the diffs. This class
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* uses the xdiff PECL package (http://pecl.php.net/package/xdiff) to compute
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* the differences between the two input arrays.
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*
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* @author Jon Parise <jon@horde.org>
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* @package Text_Diff
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* @access private
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*/
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class Text_Diff_Engine_xdiff
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{
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public function diff($from_lines, $to_lines)
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{
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/* Convert the two input arrays into strings for xdiff processing. */
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$from_string = implode("\n", $from_lines);
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$to_string = implode("\n", $to_lines);
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/* Diff the two strings and convert the result to an array. */
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$diff = xdiff_string_diff($from_string, $to_string, count($to_lines));
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$diff = explode("\n", $diff);
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/* Walk through the diff one line at a time. We build the $edits
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* array of diff operations by reading the first character of the
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* xdiff output (which is in the "unified diff" format).
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*
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* Note that we don't have enough information to detect "changed"
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* lines using this approach, so we can't add Text_Diff_Op_changed
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* instances to the $edits array. The result is still perfectly
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* valid, albeit a little less descriptive and efficient. */
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$edits = [];
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foreach ($diff as $line) {
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switch ($line[0]) {
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case ' ':
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$edits[] = new Text_Diff_Op_copy([substr($line, 1)]);
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break;
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case '+':
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$edits[] = new Text_Diff_Op_add([substr($line, 1)]);
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break;
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case '-':
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$edits[] = new Text_Diff_Op_delete([substr($line, 1)]);
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break;
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}
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}
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return $edits;
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}
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}
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/**
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* Class used internally by Diff to actually compute the diffs. This class is
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* implemented using native PHP code.
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*
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* The algorithm used here is mostly lifted from the perl module
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* Algorithm::Diff (version 1.06) by Ned Konz, which is available at:
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* http://www.perl.com/CPAN/authors/id/N/NE/NEDKONZ/Algorithm-Diff-1.06.zip
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*
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* More ideas are taken from:
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* http://www.ics.uci.edu/~eppstein/161/960229.html
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*
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* Some ideas (and a bit of code) are from from analyze.c, from GNU
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* diffutils-2.7, which can be found at:
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* ftp://gnudist.gnu.org/pub/gnu/diffutils/diffutils-2.7.tar.gz
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*
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* Some ideas (subdivision by NCHUNKS > 2, and some optimizations) are from
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* Geoffrey T. Dairiki <dairiki@dairiki.org>. The original PHP version of this
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* code was writting by him, and is used/adapted with his permission.
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*
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* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
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* @package Text_Diff
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* @access private
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*/
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class Text_Diff_Engine_native
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{
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public function diff($from_lines, $to_lines)
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{
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$n_from = count($from_lines);
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$n_to = count($to_lines);
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$this->xchanged = $this->ychanged = [];
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$this->xv = $this->yv = [];
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$this->xind = $this->yind = [];
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unset($this->seq);
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unset($this->in_seq);
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unset($this->lcs);
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// Skip leading common lines.
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for ($skip = 0; $skip < $n_from && $skip < $n_to; $skip++) {
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if ($from_lines[$skip] != $to_lines[$skip]) {
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break;
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}
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$this->xchanged[$skip] = $this->ychanged[$skip] = false;
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}
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// Skip trailing common lines.
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$xi = $n_from;
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$yi = $n_to;
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for ($endskip = 0; --$xi > $skip && --$yi > $skip; $endskip++) {
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if ($from_lines[$xi] != $to_lines[$yi]) {
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break;
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}
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$this->xchanged[$xi] = $this->ychanged[$yi] = false;
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}
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// Ignore lines which do not exist in both files.
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for ($xi = $skip; $xi < $n_from - $endskip; $xi++) {
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$xhash[$from_lines[$xi]] = 1;
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}
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for ($yi = $skip; $yi < $n_to - $endskip; $yi++) {
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$line = $to_lines[$yi];
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if (($this->ychanged[$yi] = empty($xhash[$line]))) {
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continue;
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}
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$yhash[$line] = 1;
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$this->yv[] = $line;
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$this->yind[] = $yi;
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}
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for ($xi = $skip; $xi < $n_from - $endskip; $xi++) {
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$line = $from_lines[$xi];
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if (($this->xchanged[$xi] = empty($yhash[$line]))) {
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continue;
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}
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$this->xv[] = $line;
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$this->xind[] = $xi;
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}
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// Find the LCS.
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$this->_compareseq(0, count($this->xv), 0, count($this->yv));
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// Merge edits when possible.
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$this->_shiftBoundaries($from_lines, $this->xchanged, $this->ychanged);
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$this->_shiftBoundaries($to_lines, $this->ychanged, $this->xchanged);
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// Compute the edit operations.
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$edits = [];
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$xi = $yi = 0;
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while ($xi < $n_from || $yi < $n_to) {
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// assert($yi < $n_to || $this->xchanged[$xi]);
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// assert($xi < $n_from || $this->ychanged[$yi]);
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// Skip matching "snake".
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$copy = [];
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while (
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$xi < $n_from && $yi < $n_to
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&& ! $this->xchanged[$xi] && ! $this->ychanged[$yi]
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) {
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$copy[] = $from_lines[$xi++];
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++$yi;
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}
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if ($copy) {
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$edits[] = new Text_Diff_Op_copy($copy);
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}
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// Find deletes & adds.
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$delete = [];
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while ($xi < $n_from && $this->xchanged[$xi]) {
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$delete[] = $from_lines[$xi++];
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}
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$add = [];
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while ($yi < $n_to && $this->ychanged[$yi]) {
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$add[] = $to_lines[$yi++];
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}
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if ($delete && $add) {
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$edits[] = new Text_Diff_Op_change($delete, $add);
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} elseif ($delete) {
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$edits[] = new Text_Diff_Op_delete($delete);
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} elseif ($add) {
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$edits[] = new Text_Diff_Op_add($add);
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}
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}
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return $edits;
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}
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/**
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* Divides the Largest Common Subsequence (LCS) of the sequences (XOFF,
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* XLIM) and (YOFF, YLIM) into NCHUNKS approximately equally sized
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* segments.
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*
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* Returns (LCS, PTS). LCS is the length of the LCS. PTS is an array of
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* NCHUNKS+1 (X, Y) indexes giving the diving points between sub
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* sequences. The first sub-sequence is contained in (X0, X1), (Y0, Y1),
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* the second in (X1, X2), (Y1, Y2) and so on. Note that (X0, Y0) ==
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* (XOFF, YOFF) and (X[NCHUNKS], Y[NCHUNKS]) == (XLIM, YLIM).
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*
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* This function assumes that the first lines of the specified portions of
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* the two files do not match, and likewise that the last lines do not
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* match. The caller must trim matching lines from the beginning and end
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* of the portions it is going to specify.
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*/
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public function _diag($xoff, $xlim, $yoff, $ylim, $nchunks)
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{
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$flip = false;
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if ($xlim - $xoff > $ylim - $yoff) {
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/* Things seems faster (I'm not sure I understand why) when the
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* shortest sequence is in X. */
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$flip = true;
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list ($xoff, $xlim, $yoff, $ylim)
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= [$yoff, $ylim, $xoff, $xlim];
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}
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if ($flip) {
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for ($i = $ylim - 1; $i >= $yoff; $i--) {
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$ymatches[$this->xv[$i]][] = $i;
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}
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} else {
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for ($i = $ylim - 1; $i >= $yoff; $i--) {
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$ymatches[$this->yv[$i]][] = $i;
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}
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}
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$this->lcs = 0;
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$this->seq[0] = $yoff - 1;
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$this->in_seq = [];
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$ymids[0] = [];
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$numer = $xlim - $xoff + $nchunks - 1;
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$x = $xoff;
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for ($chunk = 0; $chunk < $nchunks; $chunk++) {
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if ($chunk > 0) {
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for ($i = 0; $i <= $this->lcs; $i++) {
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$ymids[$i][$chunk - 1] = $this->seq[$i];
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}
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}
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$x1 = $xoff + (int)(($numer + ($xlim - $xoff) * $chunk) / $nchunks);
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for (; $x < $x1; $x++) {
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$line = $flip ? $this->yv[$x] : $this->xv[$x];
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if (empty($ymatches[$line])) {
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continue;
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}
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$matches = $ymatches[$line];
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foreach ($matches as $y) {
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if (empty($this->in_seq[$y])) {
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$k = $this->_lcsPos($y);
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// assert($k > 0);
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$ymids[$k] = $ymids[$k - 1];
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break;
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}
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}
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foreach ($matches as $y) {
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if ($y > $this->seq[$k - 1]) {
|
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// assert($y < $this->seq[$k]);
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|
/* Optimization: this is a common case: next match is
|
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* just replacing previous match. */
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$this->in_seq[$this->seq[$k]] = false;
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$this->seq[$k] = $y;
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$this->in_seq[$y] = 1;
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} elseif (empty($this->in_seq[$y])) {
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$k = $this->_lcsPos($y);
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// assert($k > 0);
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$ymids[$k] = $ymids[$k - 1];
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}
|
|
}
|
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}
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}
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|
$seps[] = $flip ? [$yoff, $xoff] : [$xoff, $yoff];
|
|
$ymid = $ymids[$this->lcs];
|
|
for ($n = 0; $n < $nchunks - 1; $n++) {
|
|
$x1 = $xoff + (int)(($numer + ($xlim - $xoff) * $n) / $nchunks);
|
|
$y1 = $ymid[$n] + 1;
|
|
$seps[] = $flip ? [$y1, $x1] : [$x1, $y1];
|
|
}
|
|
$seps[] = $flip ? [$ylim, $xlim] : [$xlim, $ylim];
|
|
|
|
return [$this->lcs, $seps];
|
|
}
|
|
|
|
public function _lcsPos($ypos)
|
|
{
|
|
$end = $this->lcs;
|
|
if ($end == 0 || $ypos > $this->seq[$end]) {
|
|
$this->seq[++$this->lcs] = $ypos;
|
|
$this->in_seq[$ypos] = 1;
|
|
return $this->lcs;
|
|
}
|
|
|
|
$beg = 1;
|
|
while ($beg < $end) {
|
|
$mid = (int)(($beg + $end) / 2);
|
|
if ($ypos > $this->seq[$mid]) {
|
|
$beg = $mid + 1;
|
|
} else {
|
|
$end = $mid;
|
|
}
|
|
}
|
|
|
|
// assert($ypos != $this->seq[$end]);
|
|
|
|
$this->in_seq[$this->seq[$end]] = false;
|
|
$this->seq[$end] = $ypos;
|
|
$this->in_seq[$ypos] = 1;
|
|
return $end;
|
|
}
|
|
|
|
/**
|
|
* Finds LCS of two sequences.
|
|
*
|
|
* The results are recorded in the vectors $this->{x,y}changed[], by
|
|
* storing a 1 in the element for each line that is an insertion or
|
|
* deletion (ie. is not in the LCS).
|
|
*
|
|
* The subsequence of file 0 is (XOFF, XLIM) and likewise for file 1.
|
|
*
|
|
* Note that XLIM, YLIM are exclusive bounds. All line numbers are
|
|
* origin-0 and discarded lines are not counted.
|
|
*/
|
|
public function _compareseq($xoff, $xlim, $yoff, $ylim)
|
|
{
|
|
/* Slide down the bottom initial diagonal. */
|
|
while (
|
|
$xoff < $xlim && $yoff < $ylim
|
|
&& $this->xv[$xoff] == $this->yv[$yoff]
|
|
) {
|
|
++$xoff;
|
|
++$yoff;
|
|
}
|
|
|
|
/* Slide up the top initial diagonal. */
|
|
while (
|
|
$xlim > $xoff && $ylim > $yoff
|
|
&& $this->xv[$xlim - 1] == $this->yv[$ylim - 1]
|
|
) {
|
|
--$xlim;
|
|
--$ylim;
|
|
}
|
|
|
|
if ($xoff == $xlim || $yoff == $ylim) {
|
|
$lcs = 0;
|
|
} else {
|
|
/* This is ad hoc but seems to work well. $nchunks =
|
|
* sqrt(min($xlim - $xoff, $ylim - $yoff) / 2.5); $nchunks =
|
|
* max(2,min(8,(int)$nchunks)); */
|
|
$nchunks = min(7, $xlim - $xoff, $ylim - $yoff) + 1;
|
|
list($lcs, $seps)
|
|
= $this->_diag($xoff, $xlim, $yoff, $ylim, $nchunks);
|
|
}
|
|
|
|
if ($lcs == 0) {
|
|
/* X and Y sequences have no common subsequence: mark all
|
|
* changed. */
|
|
while ($yoff < $ylim) {
|
|
$this->ychanged[$this->yind[$yoff++]] = 1;
|
|
}
|
|
while ($xoff < $xlim) {
|
|
$this->xchanged[$this->xind[$xoff++]] = 1;
|
|
}
|
|
} else {
|
|
/* Use the partitions to split this problem into subproblems. */
|
|
reset($seps);
|
|
$pt1 = $seps[0];
|
|
while ($pt2 = next($seps)) {
|
|
$this->_compareseq($pt1[0], $pt2[0], $pt1[1], $pt2[1]);
|
|
$pt1 = $pt2;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Adjusts inserts/deletes of identical lines to join changes as much as
|
|
* possible.
|
|
*
|
|
* We do something when a run of changed lines include a line at one end
|
|
* and has an excluded, identical line at the other. We are free to
|
|
* choose which identical line is included. `compareseq' usually chooses
|
|
* the one at the beginning, but usually it is cleaner to consider the
|
|
* following identical line to be the "change".
|
|
*
|
|
* This is extracted verbatim from analyze.c (GNU diffutils-2.7).
|
|
*/
|
|
public function _shiftBoundaries($lines, &$changed, $other_changed)
|
|
{
|
|
$i = 0;
|
|
$j = 0;
|
|
|
|
// assert('count($lines) == count($changed)');
|
|
$len = count($lines);
|
|
$other_len = count($other_changed);
|
|
|
|
while (1) {
|
|
/* Scan forward to find the beginning of another run of
|
|
* changes. Also keep track of the corresponding point in the
|
|
* other file.
|
|
*
|
|
* Throughout this code, $i and $j are adjusted together so that
|
|
* the first $i elements of $changed and the first $j elements of
|
|
* $other_changed both contain the same number of zeros (unchanged
|
|
* lines).
|
|
*
|
|
* Furthermore, $j is always kept so that $j == $other_len or
|
|
* $other_changed[$j] == false. */
|
|
while ($j < $other_len && $other_changed[$j]) {
|
|
$j++;
|
|
}
|
|
|
|
while ($i < $len && ! $changed[$i]) {
|
|
// assert('$j < $other_len && ! $other_changed[$j]');
|
|
$i++;
|
|
$j++;
|
|
while ($j < $other_len && $other_changed[$j]) {
|
|
$j++;
|
|
}
|
|
}
|
|
|
|
if ($i == $len) {
|
|
break;
|
|
}
|
|
|
|
$start = $i;
|
|
|
|
/* Find the end of this run of changes. */
|
|
while (++$i < $len && $changed[$i]) {
|
|
continue;
|
|
}
|
|
|
|
do {
|
|
/* Record the length of this run of changes, so that we can
|
|
* later determine whether the run has grown. */
|
|
$runlength = $i - $start;
|
|
|
|
/* Move the changed region back, so long as the previous
|
|
* unchanged line matches the last changed one. This merges
|
|
* with previous changed regions. */
|
|
while ($start > 0 && $lines[$start - 1] == $lines[$i - 1]) {
|
|
$changed[--$start] = 1;
|
|
$changed[--$i] = false;
|
|
while ($start > 0 && $changed[$start - 1]) {
|
|
$start--;
|
|
}
|
|
// assert('$j > 0');
|
|
while ($other_changed[--$j]) {
|
|
continue;
|
|
}
|
|
// assert('$j >= 0 && !$other_changed[$j]');
|
|
}
|
|
|
|
/* Set CORRESPONDING to the end of the changed run, at the
|
|
* last point where it corresponds to a changed run in the
|
|
* other file. CORRESPONDING == LEN means no such point has
|
|
* been found. */
|
|
$corresponding = $j < $other_len ? $i : $len;
|
|
|
|
/* Move the changed region forward, so long as the first
|
|
* changed line matches the following unchanged one. This
|
|
* merges with following changed regions. Do this second, so
|
|
* that if there are no merges, the changed region is moved
|
|
* forward as far as possible. */
|
|
while ($i < $len && $lines[$start] == $lines[$i]) {
|
|
$changed[$start++] = false;
|
|
$changed[$i++] = 1;
|
|
while ($i < $len && $changed[$i]) {
|
|
$i++;
|
|
}
|
|
|
|
// assert('$j < $other_len && ! $other_changed[$j]');
|
|
$j++;
|
|
if ($j < $other_len && $other_changed[$j]) {
|
|
$corresponding = $i;
|
|
while ($j < $other_len && $other_changed[$j]) {
|
|
$j++;
|
|
}
|
|
}
|
|
}
|
|
} while ($runlength != $i - $start);
|
|
|
|
/* If possible, move the fully-merged run of changes back to a
|
|
* corresponding run in the other file. */
|
|
while ($corresponding < $i) {
|
|
$changed[--$start] = 1;
|
|
$changed[--$i] = 0;
|
|
// assert('$j > 0');
|
|
while ($other_changed[--$j]) {
|
|
continue;
|
|
}
|
|
// assert('$j >= 0 && !$other_changed[$j]');
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @package Text_Diff
|
|
* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
|
|
* @access private
|
|
*/
|
|
class Text_Diff_Op
|
|
{
|
|
public $orig;
|
|
public $final;
|
|
|
|
public function reverse()
|
|
{
|
|
trigger_error('Abstract method', E_USER_ERROR);
|
|
}
|
|
|
|
public function norig()
|
|
{
|
|
return $this->orig ? count($this->orig) : 0;
|
|
}
|
|
|
|
public function nfinal()
|
|
{
|
|
return $this->final ? count($this->final) : 0;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @package Text_Diff
|
|
* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
|
|
* @access private
|
|
*/
|
|
class Text_Diff_Op_copy extends Text_Diff_Op
|
|
{
|
|
public function __construct($orig, $final = false)
|
|
{
|
|
if (! is_array($final)) {
|
|
$final = $orig;
|
|
}
|
|
$this->orig = $orig;
|
|
$this->final = $final;
|
|
}
|
|
|
|
public function &reverse()
|
|
{
|
|
return $reverse = new Text_Diff_Op_copy($this->final, $this->orig);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @package Text_Diff
|
|
* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
|
|
* @access private
|
|
*/
|
|
class Text_Diff_Op_delete extends Text_Diff_Op
|
|
{
|
|
public function __construct($lines)
|
|
{
|
|
$this->orig = $lines;
|
|
$this->final = false;
|
|
}
|
|
|
|
public function &reverse()
|
|
{
|
|
return $reverse = new Text_Diff_Op_add($this->orig);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @package Text_Diff
|
|
* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
|
|
* @access private
|
|
*/
|
|
class Text_Diff_Op_add extends Text_Diff_Op
|
|
{
|
|
public function __construct($lines)
|
|
{
|
|
$this->final = $lines;
|
|
$this->orig = false;
|
|
}
|
|
|
|
public function &reverse()
|
|
{
|
|
return $reverse = new Text_Diff_Op_delete($this->final);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @package Text_Diff
|
|
* @author Geoffrey T. Dairiki <dairiki@dairiki.org>
|
|
* @access private
|
|
*/
|
|
class Text_Diff_Op_change extends Text_Diff_Op
|
|
{
|
|
public function __construct($orig, $final)
|
|
{
|
|
$this->orig = $orig;
|
|
$this->final = $final;
|
|
}
|
|
|
|
public function &reverse()
|
|
{
|
|
return $reverse = new Text_Diff_Op_change($this->final, $this->orig);
|
|
}
|
|
}
|