Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with
or
.
Download ZIP
Browse files

MINOR Moved Diff class from cms to sapphire module (cms/code/Diff.php)


  • Loading branch information...
commit eb221ca8217085f29654b2f180035dae3e5f0233 1 parent dc36725
Paul Meyrick authored chillu committed
Showing with 869 additions and 0 deletions.
  1. +869 −0 core/Diff.php
View
869 core/Diff.php
@@ -0,0 +1,869 @@
+<?php
+
+/**
+ * @package sapphire
+ * @subpackage core
+ * A PHP diff engine
+ */
+
+// difflib.php
+//
+// A PHP diff engine for phpwiki.
+//
+// Copyright (C) 2000, 2001 Geoffrey T. Dairiki <dairiki@dairiki.org>
+// You may copy this code freely under the conditions of the GPL.
+//
+
+// FIXME: possibly remove assert()'s for production version?
+
+// PHP3 does not have assert()
+/**
+ */
+define('USE_ASSERTS', function_exists('assert'));
+
+/**
+ * @package sapphire
+ * @subpackage core
+ * @access private
+ */
+class _DiffOp {
+ var $type;
+ var $orig;
+ var $final;
+
+ function reverse() {
+ trigger_error("pure virtual", E_USER_ERROR);
+ }
+
+ function norig() {
+ return $this->orig ? sizeof($this->orig) : 0;
+ }
+
+ function nfinal() {
+ return $this->final ? sizeof($this->final) : 0;
+ }
+}
+
+/**
+ * @package sapphire
+ * @subpackage core
+ * @access private
+ */
+class _DiffOp_Copy extends _DiffOp {
+ var $type = 'copy';
+
+ function _DiffOp_Copy ($orig, $final = false) {
+ if (!is_array($final))
+ $final = $orig;
+ $this->orig = $orig;
+ $this->final = $final;
+ }
+
+ function reverse() {
+ return new _DiffOp_Copy($this->final, $this->orig);
+ }
+}
+
+/**
+ * @package sapphire
+ * @subpackage core
+ * @access private
+ */
+class _DiffOp_Delete extends _DiffOp {
+ var $type = 'delete';
+
+ function _DiffOp_Delete ($lines) {
+ $this->orig = $lines;
+ $this->final = false;
+ }
+
+ function reverse() {
+ return new _DiffOp_Add($this->orig);
+ }
+}
+
+/**
+ * @package sapphire
+ * @subpackage core
+ * @access private
+ */
+class _DiffOp_Add extends _DiffOp {
+ var $type = 'add';
+
+ function _DiffOp_Add ($lines) {
+ $this->final = $lines;
+ $this->orig = false;
+ }
+
+ function reverse() {
+ return new _DiffOp_Delete($this->final);
+ }
+}
+
+/**
+ * @package sapphire
+ * @subpackage core
+ * @access private
+ */
+class _DiffOp_Change extends _DiffOp {
+ var $type = 'change';
+
+ function _DiffOp_Change ($orig, $final) {
+ $this->orig = $orig;
+ $this->final = $final;
+ }
+
+ function reverse() {
+ return new _DiffOp_Change($this->final, $this->orig);
+ }
+}
+
+
+/**
+ * Class used internally by Diff to actually compute the diffs.
+ *
+ * The algorithm used here is mostly lifted from the perl module
+ * Algorithm::Diff (version 1.06) by Ned Konz, which is available at:
+ * http://www.perl.com/CPAN/authors/id/N/NE/NEDKONZ/Algorithm-Diff-1.06.zip
+ *
+ * More ideas are taken from:
+ * http://www.ics.uci.edu/~eppstein/161/960229.html
+ *
+ * Some ideas are (and a bit of code) are from from analyze.c, from GNU
+ * diffutils-2.7, which can be found at:
+ * ftp://gnudist.gnu.org/pub/gnu/diffutils/diffutils-2.7.tar.gz
+ *
+ * Finally, some ideas (subdivision by NCHUNKS > 2, and some optimizations)
+ * are my own.
+ *
+ * @author Geoffrey T. Dairiki
+ * @access private
+ * @package sapphire
+ * @subpackage core
+ */
+class _DiffEngine
+{
+ function diff ($from_lines, $to_lines) {
+ $n_from = sizeof($from_lines);
+ $n_to = sizeof($to_lines);
+
+ $this->xchanged = $this->ychanged = array();
+ $this->xv = $this->yv = array();
+ $this->xind = $this->yind = array();
+ unset($this->seq);
+ unset($this->in_seq);
+ unset($this->lcs);
+
+ // Skip leading common lines.
+ for ($skip = 0; $skip < $n_from && $skip < $n_to; $skip++) {
+ if ($from_lines[$skip] != $to_lines[$skip])
+ break;
+ $this->xchanged[$skip] = $this->ychanged[$skip] = false;
+ }
+ // Skip trailing common lines.
+ $xi = $n_from; $yi = $n_to;
+ for ($endskip = 0; --$xi > $skip && --$yi > $skip; $endskip++) {
+ if ($from_lines[$xi] != $to_lines[$yi])
+ break;
+ $this->xchanged[$xi] = $this->ychanged[$yi] = false;
+ }
+
+ // Ignore lines which do not exist in both files.
+ for ($xi = $skip; $xi < $n_from - $endskip; $xi++)
+ $xhash[$from_lines[$xi]] = 1;
+ for ($yi = $skip; $yi < $n_to - $endskip; $yi++) {
+ $line = $to_lines[$yi];
+ if ( ($this->ychanged[$yi] = empty($xhash[$line])) )
+ continue;
+ $yhash[$line] = 1;
+ $this->yv[] = $line;
+ $this->yind[] = $yi;
+ }
+ for ($xi = $skip; $xi < $n_from - $endskip; $xi++) {
+ $line = $from_lines[$xi];
+ if ( ($this->xchanged[$xi] = empty($yhash[$line])) )
+ continue;
+ $this->xv[] = $line;
+ $this->xind[] = $xi;
+ }
+
+ // Find the LCS.
+ $this->_compareseq(0, sizeof($this->xv), 0, sizeof($this->yv));
+
+ // Merge edits when possible
+ $this->_shift_boundaries($from_lines, $this->xchanged, $this->ychanged);
+ $this->_shift_boundaries($to_lines, $this->ychanged, $this->xchanged);
+
+ // Compute the edit operations.
+ $edits = array();
+ $xi = $yi = 0;
+ while ($xi < $n_from || $yi < $n_to) {
+ USE_ASSERTS && assert($yi < $n_to || $this->xchanged[$xi]);
+ USE_ASSERTS && assert($xi < $n_from || $this->ychanged[$yi]);
+
+ // Skip matching "snake".
+ $copy = array();
+ while ( $xi < $n_from && $yi < $n_to
+ && !$this->xchanged[$xi] && !$this->ychanged[$yi]) {
+ $copy[] = $from_lines[$xi++];
+ ++$yi;
+ }
+ if ($copy)
+ $edits[] = new _DiffOp_Copy($copy);
+
+ // Find deletes & adds.
+ $delete = array();
+ while ($xi < $n_from && $this->xchanged[$xi])
+ $delete[] = $from_lines[$xi++];
+
+ $add = array();
+ while ($yi < $n_to && $this->ychanged[$yi])
+ $add[] = $to_lines[$yi++];
+
+ if ($delete && $add)
+ $edits[] = new _DiffOp_Change($delete, $add);
+ elseif ($delete)
+ $edits[] = new _DiffOp_Delete($delete);
+ elseif ($add)
+ $edits[] = new _DiffOp_Add($add);
+ }
+ return $edits;
+ }
+
+
+ /* Divide the Largest Common Subsequence (LCS) of the sequences
+ * [XOFF, XLIM) and [YOFF, YLIM) into NCHUNKS approximately equally
+ * sized segments.
+ *
+ * Returns (LCS, PTS). LCS is the length of the LCS. PTS is an
+ * array of NCHUNKS+1 (X, Y) indexes giving the diving points between
+ * sub sequences. The first sub-sequence is contained in [X0, X1),
+ * [Y0, Y1), the second in [X1, X2), [Y1, Y2) and so on. Note
+ * that (X0, Y0) == (XOFF, YOFF) and
+ * (X[NCHUNKS], Y[NCHUNKS]) == (XLIM, YLIM).
+ *
+ * This function assumes that the first lines of the specified portions
+ * of the two files do not match, and likewise that the last lines do not
+ * match. The caller must trim matching lines from the beginning and end
+ * of the portions it is going to specify.
+ */
+ function _diag ($xoff, $xlim, $yoff, $ylim, $nchunks) {
+ $flip = false;
+
+ if ($xlim - $xoff > $ylim - $yoff) {
+ // Things seems faster (I'm not sure I understand why)
+ // when the shortest sequence in X.
+ $flip = true;
+ list ($xoff, $xlim, $yoff, $ylim)
+ = array( $yoff, $ylim, $xoff, $xlim);
+ }
+
+ if ($flip)
+ for ($i = $ylim - 1; $i >= $yoff; $i--)
+ $ymatches[$this->xv[$i]][] = $i;
+ else
+ for ($i = $ylim - 1; $i >= $yoff; $i--)
+ $ymatches[$this->yv[$i]][] = $i;
+
+ $this->lcs = 0;
+ $this->seq[0]= $yoff - 1;
+ $this->in_seq = array();
+ $ymids[0] = array();
+
+ $numer = $xlim - $xoff + $nchunks - 1;
+ $x = $xoff;
+ for ($chunk = 0; $chunk < $nchunks; $chunk++) {
+ if ($chunk > 0)
+ for ($i = 0; $i <= $this->lcs; $i++)
+ $ymids[$i][$chunk-1] = $this->seq[$i];
+
+ $x1 = $xoff + (int)(($numer + ($xlim-$xoff)*$chunk) / $nchunks);
+ for ( ; $x < $x1; $x++) {
+ $line = $flip ? $this->yv[$x] : $this->xv[$x];
+ if (empty($ymatches[$line]))
+ continue;
+ $matches = $ymatches[$line];
+ reset($matches);
+ while (list ($junk, $y) = each($matches))
+ if (empty($this->in_seq[$y])) {
+ $k = $this->_lcs_pos($y);
+ USE_ASSERTS && assert($k > 0);
+ $ymids[$k] = $ymids[$k-1];
+ break;
+ }
+ while (list ($junk, $y) = each($matches)) {
+ if ($y > $this->seq[$k-1]) {
+ USE_ASSERTS && assert($y < $this->seq[$k]);
+ // Optimization: this is a common case:
+ // next match is just replacing previous match.
+ $this->in_seq[$this->seq[$k]] = false;
+ $this->seq[$k] = $y;
+ $this->in_seq[$y] = 1;
+ }
+ else if (empty($this->in_seq[$y])) {
+ $k = $this->_lcs_pos($y);
+ USE_ASSERTS && assert($k > 0);
+ $ymids[$k] = $ymids[$k-1];
+ }
+ }
+ }
+ }
+
+ $seps[] = $flip ? array($yoff, $xoff) : array($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[] = $flip ? array($y1, $x1) : array($x1, $y1);
+ }
+ $seps[] = $flip ? array($ylim, $xlim) : array($xlim, $ylim);
+
+ return array($this->lcs, $seps);
+ }
+
+ function _lcs_pos ($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 = $mid;
+ }
+
+ USE_ASSERTS && assert($ypos != $this->seq[$end]);
+
+ $this->in_seq[$this->seq[$end]] = false;
+ $this->seq[$end] = $ypos;
+ $this->in_seq[$ypos] = 1;
+ return $end;
+ }
+
+ /* Find LCS of two sequences.
+ *
+ * The results are recorded in the vectors $this->{x,y}changed[], by
+ * storing a 1 in the element for each line that is an insertion
+ * or deletion (ie. is not in the LCS).
+ *
+ * The subsequence of file 0 is [XOFF, XLIM) and likewise for file 1.
+ *
+ * Note that XLIM, YLIM are exclusive bounds.
+ * All line numbers are origin-0 and discarded lines are not counted.
+ */
+ function _compareseq ($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 = $pt2;
+ }
+ }
+ }
+
+ /* Adjust inserts/deletes of identical lines to join changes
+ * as much as possible.
+ *
+ * We do something when a run of changed lines include a
+ * line at one end and has an excluded, identical line at the other.
+ * We are free to choose which identical line is included.
+ * 'compareseq' usually chooses the one at the beginning,
+ * but usually it is cleaner to consider the following identical line
+ * to be the "change".
+ *
+ * This is extracted verbatim from analyze.c (GNU diffutils-2.7).
+ */
+ function _shift_boundaries ($lines, &$changed, $other_changed) {
+ $i = 0;
+ $j = 0;
+
+ USE_ASSERTS && assert('sizeof($lines) == sizeof($changed)');
+ $len = sizeof($lines);
+ $other_len = sizeof($other_changed);
+
+ while (1) {
+ /*
+ * Scan forwards to find 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]) {
+ USE_ASSERTS && 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])
+ $start--;
+ USE_ASSERTS && assert('$j > 0');
+ while ($other_changed[--$j])
+ continue;
+ USE_ASSERTS && 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])
+ $i++;
+
+ USE_ASSERTS && assert('$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 sapphire
+ * @subpackage core
+ */
+class Diff
+{
+ public static $html_cleaner_class = null;
+
+ 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);
+ }
+
+
+
+ /**
+ * Attempt to clean invalid HTML, which messes up diffs.
+ * This cleans code if possible, using an instance of HTMLCleaner
+ *
+ * NB: By default, only extremely simple tidying is performed,
+ * by passing through DomDocument::loadHTML and saveXML
+ *
+ * @param string $content HTML content
+ * @param object $cleaner Optional instance of a HTMLCleaner class to
+ * use, overriding self::$html_cleaner_class
+ */
+ static function cleanHTML($content, $cleaner=null) {
+ if (!$cleaner) {
+ if (class_exists(self::$html_cleaner_class)) {
+ $cleaner = new self::$html_cleaner_class;
+ }
+ }
+ if ($cleaner) {
+ $content = $cleaner->cleanHTML($content);
+ } else {
+ // At most basic level of cleaning, use DOMDocument to save valid XML.
+ $doc = new SS_HTMLValue($content);
+ $content = $doc->getContent();
+ }
+
+ // Remove empty <ins /> and <del /> tags because browsers hate them
+ $content = preg_replace('/<(ins|del)[^>]*\/>/','', $content);
+
+ return $content;
+ }
+
+ static function compareHTML($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 self::cleanHTML($content);
+ }
+ static function getHTMLChunks($content) {
+ $content = str_replace(array("&nbsp;","<", ">"),array(" "," <", "> "),$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 sapphire
+ * @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);
+ }
+ }
+ }
+}
+
+?>
Please sign in to comment.
Something went wrong with that request. Please try again.