mirror of
https://github.com/silverstripe/silverstripe-cms
synced 2024-10-22 08:05:56 +02:00
8a831c79c5
git-svn-id: svn://svn.silverstripe.com/silverstripe/open/modules/cms/branches/2.3@81942 467b73ca-7a2a-4603-9d3b-597d59a354a9
836 lines
23 KiB
PHP
Executable File
836 lines
23 KiB
PHP
Executable File
<?php
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/**
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* @package cms
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* @subpackage core
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* A PHP diff engine
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*/
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// difflib.php
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//
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// A PHP diff engine for phpwiki.
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//
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// Copyright (C) 2000, 2001 Geoffrey T. Dairiki <dairiki@dairiki.org>
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// You may copy this code freely under the conditions of the GPL.
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//
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// FIXME: possibly remove assert()'s for production version?
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// PHP3 does not have assert()
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/**
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*/
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define('USE_ASSERTS', function_exists('assert'));
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/**
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* @package cms
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* @subpackage core
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* @access private
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*/
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class _DiffOp {
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var $type;
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var $orig;
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var $final;
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function reverse() {
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trigger_error("pure virtual", E_USER_ERROR);
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}
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function norig() {
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return $this->orig ? sizeof($this->orig) : 0;
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}
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function nfinal() {
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return $this->final ? sizeof($this->final) : 0;
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}
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}
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/**
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* @package cms
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* @subpackage core
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* @access private
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*/
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class _DiffOp_Copy extends _DiffOp {
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var $type = 'copy';
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function _DiffOp_Copy ($orig, $final = false) {
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if (!is_array($final))
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$final = $orig;
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$this->orig = $orig;
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$this->final = $final;
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}
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function reverse() {
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return new _DiffOp_Copy($this->final, $this->orig);
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}
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}
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/**
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* @package cms
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* @subpackage core
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* @access private
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*/
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class _DiffOp_Delete extends _DiffOp {
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var $type = 'delete';
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function _DiffOp_Delete ($lines) {
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$this->orig = $lines;
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$this->final = false;
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}
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function reverse() {
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return new _DiffOp_Add($this->orig);
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}
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}
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/**
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* @package cms
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* @subpackage core
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* @access private
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*/
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class _DiffOp_Add extends _DiffOp {
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var $type = 'add';
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function _DiffOp_Add ($lines) {
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$this->final = $lines;
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$this->orig = false;
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}
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function reverse() {
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return new _DiffOp_Delete($this->final);
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}
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}
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/**
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* @package cms
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* @subpackage core
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* @access private
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*/
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class _DiffOp_Change extends _DiffOp {
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var $type = 'change';
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function _DiffOp_Change ($orig, $final) {
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$this->orig = $orig;
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$this->final = $final;
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}
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function reverse() {
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return new _DiffOp_Change($this->final, $this->orig);
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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.
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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 are (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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* Finally, some ideas (subdivision by NCHUNKS > 2, and some optimizations)
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* are my own.
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*
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* @author Geoffrey T. Dairiki
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* @access private
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* @package cms
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* @subpackage core
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*/
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class _DiffEngine
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{
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function diff ($from_lines, $to_lines) {
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$n_from = sizeof($from_lines);
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$n_to = sizeof($to_lines);
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$this->xchanged = $this->ychanged = array();
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$this->xv = $this->yv = array();
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$this->xind = $this->yind = array();
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unset($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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$this->xchanged[$skip] = $this->ychanged[$skip] = false;
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}
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// Skip trailing common lines.
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$xi = $n_from; $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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$this->xchanged[$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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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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$yhash[$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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$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, sizeof($this->xv), 0, sizeof($this->yv));
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// Merge edits when possible
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$this->_shift_boundaries($from_lines, $this->xchanged, $this->ychanged);
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$this->_shift_boundaries($to_lines, $this->ychanged, $this->xchanged);
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// Compute the edit operations.
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$edits = array();
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$xi = $yi = 0;
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while ($xi < $n_from || $yi < $n_to) {
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USE_ASSERTS && assert($yi < $n_to || $this->xchanged[$xi]);
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USE_ASSERTS && assert($xi < $n_from || $this->ychanged[$yi]);
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// Skip matching "snake".
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$copy = array();
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while ( $xi < $n_from && $yi < $n_to
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&& !$this->xchanged[$xi] && !$this->ychanged[$yi]) {
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$copy[] = $from_lines[$xi++];
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++$yi;
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}
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if ($copy)
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$edits[] = new _DiffOp_Copy($copy);
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// Find deletes & adds.
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$delete = array();
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while ($xi < $n_from && $this->xchanged[$xi])
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$delete[] = $from_lines[$xi++];
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$add = array();
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while ($yi < $n_to && $this->ychanged[$yi])
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$add[] = $to_lines[$yi++];
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if ($delete && $add)
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$edits[] = new _DiffOp_Change($delete, $add);
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elseif ($delete)
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$edits[] = new _DiffOp_Delete($delete);
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elseif ($add)
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$edits[] = new _DiffOp_Add($add);
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}
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return $edits;
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}
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/* Divide the Largest Common Subsequence (LCS) of the sequences
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* [XOFF, XLIM) and [YOFF, YLIM) into NCHUNKS approximately equally
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* sized segments.
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*
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* Returns (LCS, PTS). LCS is the length of the LCS. PTS is an
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* array of NCHUNKS+1 (X, Y) indexes giving the diving points between
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* sub sequences. The first sub-sequence is contained in [X0, X1),
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* [Y0, Y1), the second in [X1, X2), [Y1, Y2) and so on. Note
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* that (X0, Y0) == (XOFF, YOFF) and
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* (X[NCHUNKS], Y[NCHUNKS]) == (XLIM, YLIM).
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*
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* This function assumes that the first lines of the specified portions
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* of the two files do not match, and likewise that the last lines do not
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* match. The caller must trim matching lines from the beginning and end
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* of the portions it is going to specify.
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*/
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function _diag ($xoff, $xlim, $yoff, $ylim, $nchunks) {
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$flip = false;
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if ($xlim - $xoff > $ylim - $yoff) {
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// Things seems faster (I'm not sure I understand why)
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// when the shortest sequence in X.
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$flip = true;
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list ($xoff, $xlim, $yoff, $ylim)
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= array( $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]][] = $i;
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else
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for ($i = $ylim - 1; $i >= $yoff; $i--)
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$ymatches[$this->yv[$i]][] = $i;
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$this->lcs = 0;
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$this->seq[0]= $yoff - 1;
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$this->in_seq = array();
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$ymids[0] = array();
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$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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$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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$matches = $ymatches[$line];
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reset($matches);
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while (list ($junk, $y) = each($matches))
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if (empty($this->in_seq[$y])) {
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$k = $this->_lcs_pos($y);
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USE_ASSERTS && 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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while (list ($junk, $y) = each($matches)) {
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if ($y > $this->seq[$k-1]) {
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USE_ASSERTS && assert($y < $this->seq[$k]);
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// Optimization: this is a common case:
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// next match is 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[$y] = 1;
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}
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else if (empty($this->in_seq[$y])) {
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$k = $this->_lcs_pos($y);
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USE_ASSERTS && 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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}
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$seps[] = $flip ? array($yoff, $xoff) : array($xoff, $yoff);
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$ymid = $ymids[$this->lcs];
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for ($n = 0; $n < $nchunks - 1; $n++) {
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$x1 = $xoff + (int)(($numer + ($xlim - $xoff) * $n) / $nchunks);
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$y1 = $ymid[$n] + 1;
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$seps[] = $flip ? array($y1, $x1) : array($x1, $y1);
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}
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$seps[] = $flip ? array($ylim, $xlim) : array($xlim, $ylim);
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return array($this->lcs, $seps);
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}
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function _lcs_pos ($ypos) {
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$end = $this->lcs;
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if ($end == 0 || $ypos > $this->seq[$end]) {
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$this->seq[++$this->lcs] = $ypos;
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$this->in_seq[$ypos] = 1;
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return $this->lcs;
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}
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$beg = 1;
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while ($beg < $end) {
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$mid = (int)(($beg + $end) / 2);
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if ( $ypos > $this->seq[$mid] )
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$beg = $mid + 1;
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else
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$end = $mid;
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}
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USE_ASSERTS && assert($ypos != $this->seq[$end]);
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$this->in_seq[$this->seq[$end]] = false;
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$this->seq[$end] = $ypos;
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$this->in_seq[$ypos] = 1;
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return $end;
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}
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/* Find LCS of two sequences.
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*
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* The results are recorded in the vectors $this->{x,y}changed[], by
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* storing a 1 in the element for each line that is an insertion
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* or deletion (ie. is not in the LCS).
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*
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* The subsequence of file 0 is [XOFF, XLIM) and likewise for file 1.
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*
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* Note that XLIM, YLIM are exclusive bounds.
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* All line numbers are origin-0 and discarded lines are not counted.
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*/
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function _compareseq ($xoff, $xlim, $yoff, $ylim) {
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// Slide down the bottom initial diagonal.
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while ($xoff < $xlim && $yoff < $ylim
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&& $this->xv[$xoff] == $this->yv[$yoff]) {
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++$xoff;
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++$yoff;
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}
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// Slide up the top initial diagonal.
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while ($xlim > $xoff && $ylim > $yoff
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&& $this->xv[$xlim - 1] == $this->yv[$ylim - 1]) {
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--$xlim;
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--$ylim;
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}
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if ($xoff == $xlim || $yoff == $ylim)
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$lcs = 0;
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else {
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// This is ad hoc but seems to work well.
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//$nchunks = sqrt(min($xlim - $xoff, $ylim - $yoff) / 2.5);
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//$nchunks = max(2,min(8,(int)$nchunks));
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$nchunks = min(7, $xlim - $xoff, $ylim - $yoff) + 1;
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list ($lcs, $seps)
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= $this->_diag($xoff,$xlim,$yoff, $ylim,$nchunks);
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}
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if ($lcs == 0) {
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// X and Y sequences have no common subsequence:
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// mark all changed.
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while ($yoff < $ylim)
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$this->ychanged[$this->yind[$yoff++]] = 1;
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while ($xoff < $xlim)
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$this->xchanged[$this->xind[$xoff++]] = 1;
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}
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else {
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// Use the partitions to split this problem into subproblems.
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reset($seps);
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$pt1 = $seps[0];
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while ($pt2 = next($seps)) {
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$this->_compareseq ($pt1[0], $pt2[0], $pt1[1], $pt2[1]);
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$pt1 = $pt2;
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}
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}
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}
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/* Adjust inserts/deletes of identical lines to join changes
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* as much as possible.
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*
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* We do something when a run of changed lines include a
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* line at one end and has an excluded, identical line at the other.
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* We are free to choose which identical line is included.
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* `compareseq' usually chooses the one at the beginning,
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* but usually it is cleaner to consider the following identical line
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* to be the "change".
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*
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* This is extracted verbatim from analyze.c (GNU diffutils-2.7).
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*/
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function _shift_boundaries ($lines, &$changed, $other_changed) {
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$i = 0;
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$j = 0;
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USE_ASSERTS && assert('sizeof($lines) == sizeof($changed)');
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$len = sizeof($lines);
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$other_len = sizeof($other_changed);
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while (1) {
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/*
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* Scan forwards to find beginning of another run of changes.
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* Also keep track of the corresponding point in the other file.
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*
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* Throughout this code, $i and $j are adjusted together so that
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* the first $i elements of $changed and the first $j elements
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* of $other_changed both contain the same number of zeros
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* (unchanged lines).
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* Furthermore, $j is always kept so that $j == $other_len or
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* $other_changed[$j] == false.
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*/
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while ($j < $other_len && $other_changed[$j])
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$j++;
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while ($i < $len && ! $changed[$i]) {
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USE_ASSERTS && assert('$j < $other_len && ! $other_changed[$j]');
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$i++; $j++;
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while ($j < $other_len && $other_changed[$j])
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$j++;
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}
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if ($i == $len)
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break;
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$start = $i;
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// Find the end of this run of changes.
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while (++$i < $len && $changed[$i])
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continue;
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do {
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/*
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* Record the length of this run of changes, so that
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* we can later determine whether the run has grown.
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*/
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$runlength = $i - $start;
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/*
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* Move the changed region back, so long as the
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* previous unchanged line matches the last changed one.
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* This merges with previous changed regions.
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*/
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while ($start > 0 && $lines[$start - 1] == $lines[$i - 1]) {
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$changed[--$start] = 1;
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$changed[--$i] = false;
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while ($start > 0 && $changed[$start - 1])
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$start--;
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USE_ASSERTS && assert('$j > 0');
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while ($other_changed[--$j])
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continue;
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USE_ASSERTS && assert('$j >= 0 && !$other_changed[$j]');
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}
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/*
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* Set CORRESPONDING to the end of the changed run, at the last
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* point where it corresponds to a changed run in the other file.
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* CORRESPONDING == LEN means no such point has been found.
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*/
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$corresponding = $j < $other_len ? $i : $len;
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/*
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* Move the changed region forward, so long as the
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* first changed line matches the following unchanged one.
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* This merges with following changed regions.
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* Do this second, so that if there are no merges,
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* the changed region is moved forward as far as possible.
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*/
|
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while ($i < $len && $lines[$start] == $lines[$i]) {
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$changed[$start++] = false;
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$changed[$i++] = 1;
|
|
while ($i < $len && $changed[$i])
|
|
$i++;
|
|
|
|
USE_ASSERTS && assert('$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;
|
|
USE_ASSERTS && assert('$j > 0');
|
|
while ($other_changed[--$j])
|
|
continue;
|
|
USE_ASSERTS && assert('$j >= 0 && !$other_changed[$j]');
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Class representing a 'diff' between two sequences of strings.
|
|
* @package cms
|
|
* @subpackage core
|
|
*/
|
|
class Diff
|
|
{
|
|
var $edits;
|
|
|
|
/**
|
|
* Constructor.
|
|
* Computes diff between sequences of strings.
|
|
*
|
|
* @param $from_lines array An array of strings.
|
|
* (Typically these are lines from a file.)
|
|
* @param $to_lines array An array of strings.
|
|
*/
|
|
function Diff($from_lines, $to_lines) {
|
|
$eng = new _DiffEngine;
|
|
$this->edits = $eng->diff($from_lines, $to_lines);
|
|
//$this->_check($from_lines, $to_lines);
|
|
}
|
|
|
|
/**
|
|
* Compute reversed Diff.
|
|
*
|
|
* SYNOPSIS:
|
|
*
|
|
* $diff = new Diff($lines1, $lines2);
|
|
* $rev = $diff->reverse();
|
|
* @return object A Diff object representing the inverse of the
|
|
* original diff.
|
|
*/
|
|
function reverse () {
|
|
$rev = $this;
|
|
$rev->edits = array();
|
|
foreach ($this->edits as $edit) {
|
|
$rev->edits[] = $edit->reverse();
|
|
}
|
|
return $rev;
|
|
}
|
|
|
|
/**
|
|
* Check for empty diff.
|
|
*
|
|
* @return bool True iff two sequences were identical.
|
|
*/
|
|
function isEmpty () {
|
|
foreach ($this->edits as $edit) {
|
|
if ($edit->type != 'copy')
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Compute the length of the Longest Common Subsequence (LCS).
|
|
*
|
|
* This is mostly for diagnostic purposed.
|
|
*
|
|
* @return int The length of the LCS.
|
|
*/
|
|
function lcs () {
|
|
$lcs = 0;
|
|
foreach ($this->edits as $edit) {
|
|
if ($edit->type == 'copy')
|
|
$lcs += sizeof($edit->orig);
|
|
}
|
|
return $lcs;
|
|
}
|
|
|
|
/**
|
|
* Get the original set of lines.
|
|
*
|
|
* This reconstructs the $from_lines parameter passed to the
|
|
* constructor.
|
|
*
|
|
* @return array The original sequence of strings.
|
|
*/
|
|
function orig() {
|
|
$lines = array();
|
|
|
|
foreach ($this->edits as $edit) {
|
|
if ($edit->orig)
|
|
array_splice($lines, sizeof($lines), 0, $edit->orig);
|
|
}
|
|
return $lines;
|
|
}
|
|
|
|
/**
|
|
* Get the final set of lines.
|
|
*
|
|
* This reconstructs the $to_lines parameter passed to the
|
|
* constructor.
|
|
*
|
|
* @return array The sequence of strings.
|
|
*/
|
|
function finaltext() {
|
|
$lines = array();
|
|
|
|
foreach ($this->edits as $edit) {
|
|
if ($edit->final)
|
|
array_splice($lines, sizeof($lines), 0, $edit->final);
|
|
}
|
|
return $lines;
|
|
}
|
|
|
|
/**
|
|
* Check a Diff for validity.
|
|
*
|
|
* This is here only for debugging purposes.
|
|
*/
|
|
function _check ($from_lines, $to_lines) {
|
|
if (serialize($from_lines) != serialize($this->orig()))
|
|
trigger_error("Reconstructed original doesn't match", E_USER_ERROR);
|
|
if (serialize($to_lines) != serialize($this->finaltext()))
|
|
trigger_error("Reconstructed final doesn't match", E_USER_ERROR);
|
|
|
|
$rev = $this->reverse();
|
|
if (serialize($to_lines) != serialize($rev->orig()))
|
|
trigger_error("Reversed original doesn't match", E_USER_ERROR);
|
|
if (serialize($from_lines) != serialize($rev->finaltext()))
|
|
trigger_error("Reversed final doesn't match", E_USER_ERROR);
|
|
|
|
|
|
$prevtype = 'none';
|
|
foreach ($this->edits as $edit) {
|
|
if ( $prevtype == $edit->type )
|
|
trigger_error("Edit sequence is non-optimal", E_USER_ERROR);
|
|
$prevtype = $edit->type;
|
|
}
|
|
|
|
$lcs = $this->lcs();
|
|
trigger_error("Diff okay: LCS = $lcs", E_USER_NOTICE);
|
|
}
|
|
|
|
|
|
|
|
static function compareHTML($from, $to) {
|
|
// First split up the content into words and tags
|
|
$set1 = self::getHTMLChunks($from);
|
|
$set2 = self::getHTMLChunks($to);
|
|
|
|
// Diff that
|
|
$diff = new Diff($set1, $set2);
|
|
|
|
$tagStack[1] = $tagStack[2] = 0;
|
|
$rechunked[1] = $rechunked[2] = array();
|
|
|
|
// Go through everything, converting edited tags (and their content) into single chunks. Otherwise
|
|
// the generated HTML gets crusty
|
|
foreach($diff->edits as $edit) {
|
|
//echo "<li>$edit->type: " . htmlentities(implode(" " ,$edit->orig));
|
|
//if($edit->final) echo ' / ' . htmlentities(implode(" " ,$edit->final));
|
|
|
|
switch($edit->type) {
|
|
case 'copy':
|
|
$lookForTag = false;
|
|
$stuffFor[1] = $edit->orig;
|
|
$stuffFor[2] = $edit->orig;
|
|
break;
|
|
|
|
case 'change':
|
|
$lookForTag = true;
|
|
$stuffFor[1] = $edit->orig;
|
|
$stuffFor[2] = $edit->final;
|
|
break;
|
|
|
|
case 'add':
|
|
$lookForTag = true;
|
|
$stuffFor[1] = null;
|
|
$stuffFor[2] = $edit->final;
|
|
break;
|
|
|
|
case 'delete':
|
|
$lookForTag = true;
|
|
$stuffFor[1] = $edit->orig;
|
|
$stuffFor[2] = null;
|
|
break;
|
|
}
|
|
|
|
foreach($stuffFor as $listName => $chunks) {
|
|
if($chunks) {
|
|
foreach($chunks as $item) {
|
|
// $tagStack > 0 indicates that we should be tag-building
|
|
if($tagStack[$listName]) $rechunked[$listName][sizeof($rechunked[$listName])-1] .= ' ' . $item;
|
|
else $rechunked[$listName][] = $item;
|
|
|
|
if($lookForTag && isset($item[0]) && $item[0] == "<" && substr($item,0,2) != "</") {
|
|
$tagStack[$listName] = 1;
|
|
} else if($tagStack[$listName]) {
|
|
if(substr($item,0,2) == "</") $tagStack[$listName]--;
|
|
else if(isset($item[0]) && $item[0] == "<") $tagStack[$listName]++;
|
|
}
|
|
|
|
// echo "<li>" . htmlentities($item) . " -> " .$tagStack[$listName];
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Diff the re-chunked data, turning it into maked up HTML
|
|
$diff = new Diff($rechunked[1], $rechunked[2]);
|
|
$content = '';
|
|
foreach($diff->edits as $edit) {
|
|
// echo "<li>$edit->type: " . htmlentities(implode(" " ,$edit->orig));
|
|
// if($edit->final) echo ' / ' . htmlentities(implode(" " ,$edit->final));
|
|
|
|
switch($edit->type) {
|
|
case 'copy':
|
|
$content .= " " . implode(" ", $edit->orig) . " ";
|
|
break;
|
|
|
|
case 'change':
|
|
$content .= " <ins>" . implode(" ", $edit->final) . "</ins> ";
|
|
$content .= " <del>" . implode(" ", $edit->orig) . "</del> ";
|
|
break;
|
|
|
|
case 'add':
|
|
$content .= " <ins>" . implode(" ", $edit->final) . "</ins> ";
|
|
break;
|
|
|
|
case 'delete':
|
|
$content .= " <del>" . implode(" ", $edit->orig) . "</del> ";
|
|
break;
|
|
}
|
|
}
|
|
// echo "<p>" . htmlentities($content) . "</p>";
|
|
return $content;
|
|
}
|
|
static function getHTMLChunks($content) {
|
|
$content = str_replace(array(" ","<", ">"),array(" "," <", "> "),$content);
|
|
$candidateChunks = split("[\t\r\n ]+", $content);
|
|
while(list($i,$item) = each($candidateChunks)) {
|
|
if(isset($item[0]) && $item[0] == "<") {
|
|
$newChunk = $item;
|
|
while($item[strlen($item)-1] != ">") {
|
|
list($i,$item) = each($candidateChunks);
|
|
$newChunk .= ' ' . $item;
|
|
}
|
|
$chunks[] = $newChunk;
|
|
} else {
|
|
$chunks[] = $item;
|
|
}
|
|
}
|
|
return $chunks;
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/**
|
|
* Computes diff between sequences of strings.
|
|
* @package cms
|
|
* @subpackage core
|
|
*/
|
|
class MappedDiff
|
|
extends Diff
|
|
{
|
|
/**
|
|
* Constructor.
|
|
*
|
|
* Computes diff between sequences of strings.
|
|
*
|
|
* This can be used to compute things like
|
|
* case-insensitve diffs, or diffs which ignore
|
|
* changes in white-space.
|
|
*
|
|
* @param $from_lines array An array of strings.
|
|
* (Typically these are lines from a file.)
|
|
*
|
|
* @param $to_lines array An array of strings.
|
|
*
|
|
* @param $mapped_from_lines array This array should
|
|
* have the same size number of elements as $from_lines.
|
|
* The elements in $mapped_from_lines and
|
|
* $mapped_to_lines are what is actually compared
|
|
* when computing the diff.
|
|
*
|
|
* @param $mapped_to_lines array This array should
|
|
* have the same number of elements as $to_lines.
|
|
*/
|
|
function MappedDiff($from_lines, $to_lines,
|
|
$mapped_from_lines, $mapped_to_lines) {
|
|
|
|
assert(sizeof($from_lines) == sizeof($mapped_from_lines));
|
|
assert(sizeof($to_lines) == sizeof($mapped_to_lines));
|
|
|
|
$this->Diff($mapped_from_lines, $mapped_to_lines);
|
|
|
|
$xi = $yi = 0;
|
|
// Optimizing loop invariants:
|
|
// http://phplens.com/lens/php-book/optimizing-debugging-php.php
|
|
for ($i = 0, $max = sizeof($this->edits); $i < $max; $i++) {
|
|
$orig = &$this->edits[$i]->orig;
|
|
if (is_array($orig)) {
|
|
$orig = array_slice($from_lines, $xi, sizeof($orig));
|
|
$xi += sizeof($orig);
|
|
}
|
|
|
|
$final = &$this->edits[$i]->final;
|
|
if (is_array($final)) {
|
|
$final = array_slice($to_lines, $yi, sizeof($final));
|
|
$yi += sizeof($final);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
?>
|