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Diffstat (limited to 'includes/DifferenceEngine.php')
| -rw-r--r-- | includes/DifferenceEngine.php | 1751 |
1 files changed, 1751 insertions, 0 deletions
diff --git a/includes/DifferenceEngine.php b/includes/DifferenceEngine.php new file mode 100644 index 00000000..741b7199 --- /dev/null +++ b/includes/DifferenceEngine.php @@ -0,0 +1,1751 @@ +<?php +/** + * See diff.doc + * @package MediaWiki + * @subpackage DifferenceEngine + */ + +/** */ +define( 'MAX_DIFF_LINE', 10000 ); +define( 'MAX_DIFF_XREF_LENGTH', 10000 ); + +/** + * @todo document + * @public + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class DifferenceEngine { + /**#@+ + * @private + */ + var $mOldid, $mNewid, $mTitle; + var $mOldtitle, $mNewtitle, $mPagetitle; + var $mOldtext, $mNewtext; + var $mOldPage, $mNewPage; + var $mRcidMarkPatrolled; + var $mOldRev, $mNewRev; + var $mRevisionsLoaded = false; // Have the revisions been loaded + var $mTextLoaded = 0; // How many text blobs have been loaded, 0, 1 or 2? + /**#@-*/ + + /** + * Constructor + * @param $titleObj Title object that the diff is associated with + * @param $old Integer: old ID we want to show and diff with. + * @param $new String: either 'prev' or 'next'. + * @param $rcid Integer: ??? FIXME (default 0) + */ + function DifferenceEngine( $titleObj = null, $old = 0, $new = 0, $rcid = 0 ) { + $this->mTitle = $titleObj; + wfDebug("DifferenceEngine old '$old' new '$new' rcid '$rcid'\n"); + + if ( 'prev' === $new ) { + # Show diff between revision $old and the previous one. + # Get previous one from DB. + # + $this->mNewid = intval($old); + + $this->mOldid = $this->mTitle->getPreviousRevisionID( $this->mNewid ); + + } elseif ( 'next' === $new ) { + # Show diff between revision $old and the previous one. + # Get previous one from DB. + # + $this->mOldid = intval($old); + $this->mNewid = $this->mTitle->getNextRevisionID( $this->mOldid ); + if ( false === $this->mNewid ) { + # if no result, NewId points to the newest old revision. The only newer + # revision is cur, which is "0". + $this->mNewid = 0; + } + + } else { + $this->mOldid = intval($old); + $this->mNewid = intval($new); + } + $this->mRcidMarkPatrolled = intval($rcid); # force it to be an integer + } + + function showDiffPage() { + global $wgUser, $wgOut, $wgContLang, $wgUseExternalEditor, $wgUseRCPatrol; + $fname = 'DifferenceEngine::showDiffPage'; + wfProfileIn( $fname ); + + # If external diffs are enabled both globally and for the user, + # we'll use the application/x-external-editor interface to call + # an external diff tool like kompare, kdiff3, etc. + if($wgUseExternalEditor && $wgUser->getOption('externaldiff')) { + global $wgInputEncoding,$wgServer,$wgScript,$wgLang; + $wgOut->disable(); + header ( "Content-type: application/x-external-editor; charset=".$wgInputEncoding ); + $url1=$this->mTitle->getFullURL("action=raw&oldid=".$this->mOldid); + $url2=$this->mTitle->getFullURL("action=raw&oldid=".$this->mNewid); + $special=$wgLang->getNsText(NS_SPECIAL); + $control=<<<CONTROL +[Process] +Type=Diff text +Engine=MediaWiki +Script={$wgServer}{$wgScript} +Special namespace={$special} + +[File] +Extension=wiki +URL=$url1 + +[File 2] +Extension=wiki +URL=$url2 +CONTROL; + echo($control); + return; + } + + $t = $this->mTitle->getPrefixedText() . " (Diff: {$this->mOldid}, " . + "{$this->mNewid})"; + $mtext = wfMsg( 'missingarticle', "<nowiki>$t</nowiki>" ); + + $wgOut->setArticleFlag( false ); + if ( ! $this->loadRevisionData() ) { + $wgOut->setPagetitle( wfMsg( 'errorpagetitle' ) ); + $wgOut->addWikitext( $mtext ); + wfProfileOut( $fname ); + return; + } + + wfRunHooks( 'DiffViewHeader', array( $this, $this->mOldRev, $this->mNewRev ) ); + + if ( $this->mNewRev->isCurrent() ) { + $wgOut->setArticleFlag( true ); + } + + # mOldid is false if the difference engine is called with a "vague" query for + # a diff between a version V and its previous version V' AND the version V + # is the first version of that article. In that case, V' does not exist. + if ( $this->mOldid === false ) { + $this->showFirstRevision(); + wfProfileOut( $fname ); + return; + } + + $wgOut->suppressQuickbar(); + + $oldTitle = $this->mOldPage->getPrefixedText(); + $newTitle = $this->mNewPage->getPrefixedText(); + if( $oldTitle == $newTitle ) { + $wgOut->setPageTitle( $newTitle ); + } else { + $wgOut->setPageTitle( $oldTitle . ', ' . $newTitle ); + } + $wgOut->setSubtitle( wfMsg( 'difference' ) ); + $wgOut->setRobotpolicy( 'noindex,nofollow' ); + + if ( !( $this->mOldPage->userCanRead() && $this->mNewPage->userCanRead() ) ) { + $wgOut->loginToUse(); + $wgOut->output(); + wfProfileOut( $fname ); + exit; + } + + $sk = $wgUser->getSkin(); + $talk = $wgContLang->getNsText( NS_TALK ); + $contribs = wfMsg( 'contribslink' ); + + if ( $this->mNewRev->isCurrent() && $wgUser->isAllowed('rollback') ) { + $username = $this->mNewRev->getUserText(); + $rollback = ' <strong>[' . $sk->makeKnownLinkObj( $this->mTitle, wfMsg( 'rollbacklink' ), + 'action=rollback&from=' . urlencode( $username ) . + '&token=' . urlencode( $wgUser->editToken( array( $this->mTitle->getPrefixedText(), $username ) ) ) ) . + ']</strong>'; + } else { + $rollback = ''; + } + if( $wgUseRCPatrol && $this->mRcidMarkPatrolled != 0 && $wgUser->isAllowed( 'patrol' ) ) { + $patrol = ' [' . $sk->makeKnownLinkObj( $this->mTitle, wfMsg( 'markaspatrolleddiff' ), "action=markpatrolled&rcid={$this->mRcidMarkPatrolled}" ) . ']'; + } else { + $patrol = ''; + } + + $prevlink = $sk->makeKnownLinkObj( $this->mTitle, wfMsgHtml( 'previousdiff' ), + 'diff=prev&oldid='.$this->mOldid, '', '', 'id="differences-prevlink"' ); + if ( $this->mNewRev->isCurrent() ) { + $nextlink = ' '; + } else { + $nextlink = $sk->makeKnownLinkObj( $this->mTitle, wfMsgHtml( 'nextdiff' ), + 'diff=next&oldid='.$this->mNewid, '', '', 'id="differences-nextlink"' ); + } + + $oldHeader = "<strong>{$this->mOldtitle}</strong><br />" . + $sk->revUserTools( $this->mOldRev ) . "<br />" . + $sk->revComment( $this->mOldRev ) . "<br />" . + $prevlink; + $newHeader = "<strong>{$this->mNewtitle}</strong><br />" . + $sk->revUserTools( $this->mNewRev ) . " $rollback<br />" . + $sk->revComment( $this->mNewRev ) . "<br />" . + $nextlink . $patrol; + + $this->showDiff( $oldHeader, $newHeader ); + $wgOut->addHTML( "<hr /><h2>{$this->mPagetitle}</h2>\n" ); + + if( !$this->mNewRev->isCurrent() ) { + $oldEditSectionSetting = $wgOut->mParserOptions->setEditSection( false ); + } + + $this->loadNewText(); + if( is_object( $this->mNewRev ) ) { + $wgOut->setRevisionId( $this->mNewRev->getId() ); + } + $wgOut->addSecondaryWikiText( $this->mNewtext ); + + if( !$this->mNewRev->isCurrent() ) { + $wgOut->mParserOptions->setEditSection( $oldEditSectionSetting ); + } + + wfProfileOut( $fname ); + } + + /** + * Show the first revision of an article. Uses normal diff headers in + * contrast to normal "old revision" display style. + */ + function showFirstRevision() { + global $wgOut, $wgUser; + + $fname = 'DifferenceEngine::showFirstRevision'; + wfProfileIn( $fname ); + + # Get article text from the DB + # + if ( ! $this->loadNewText() ) { + $t = $this->mTitle->getPrefixedText() . " (Diff: {$this->mOldid}, " . + "{$this->mNewid})"; + $mtext = wfMsg( 'missingarticle', "<nowiki>$t</nowiki>" ); + $wgOut->setPagetitle( wfMsg( 'errorpagetitle' ) ); + $wgOut->addWikitext( $mtext ); + wfProfileOut( $fname ); + return; + } + if ( $this->mNewRev->isCurrent() ) { + $wgOut->setArticleFlag( true ); + } + + # Check if user is allowed to look at this page. If not, bail out. + # + if ( !( $this->mTitle->userCanRead() ) ) { + $wgOut->loginToUse(); + $wgOut->output(); + wfProfileOut( $fname ); + exit; + } + + # Prepare the header box + # + $sk = $wgUser->getSkin(); + + $nextlink = $sk->makeKnownLinkObj( $this->mTitle, wfMsgHtml( 'nextdiff' ), 'diff=next&oldid='.$this->mNewid, '', '', 'id="differences-nextlink"' ); + $header = "<div class=\"firstrevisionheader\" style=\"text-align: center\"><strong>{$this->mOldtitle}</strong><br />" . + $sk->revUserTools( $this->mNewRev ) . "<br />" . + $sk->revComment( $this->mNewRev ) . "<br />" . + $nextlink . "</div>\n"; + + $wgOut->addHTML( $header ); + + $wgOut->setSubtitle( wfMsg( 'difference' ) ); + $wgOut->setRobotpolicy( 'noindex,nofollow' ); + + + # Show current revision + # + $wgOut->addHTML( "<hr /><h2>{$this->mPagetitle}</h2>\n" ); + if( is_object( $this->mNewRev ) ) { + $wgOut->setRevisionId( $this->mNewRev->getId() ); + } + $wgOut->addSecondaryWikiText( $this->mNewtext ); + + wfProfileOut( $fname ); + } + + /** + * Get the diff text, send it to $wgOut + * Returns false if the diff could not be generated, otherwise returns true + */ + function showDiff( $otitle, $ntitle ) { + global $wgOut; + $diff = $this->getDiff( $otitle, $ntitle ); + if ( $diff === false ) { + $wgOut->addWikitext( wfMsg( 'missingarticle', "<nowiki>(fixme, bug)</nowiki>" ) ); + return false; + } else { + $wgOut->addHTML( $diff ); + return true; + } + } + + /** + * Get diff table, including header + * Note that the interface has changed, it's no longer static. + * Returns false on error + */ + function getDiff( $otitle, $ntitle ) { + $body = $this->getDiffBody(); + if ( $body === false ) { + return false; + } else { + return $this->addHeader( $body, $otitle, $ntitle ); + } + } + + /** + * Get the diff table body, without header + * Results are cached + * Returns false on error + */ + function getDiffBody() { + global $wgMemc, $wgDBname; + $fname = 'DifferenceEngine::getDiffBody'; + wfProfileIn( $fname ); + + // Cacheable? + $key = false; + if ( $this->mOldid && $this->mNewid ) { + // Try cache + $key = "$wgDBname:diff:oldid:{$this->mOldid}:newid:{$this->mNewid}"; + $difftext = $wgMemc->get( $key ); + if ( $difftext ) { + wfIncrStats( 'diff_cache_hit' ); + $difftext = $this->localiseLineNumbers( $difftext ); + $difftext .= "\n<!-- diff cache key $key -->\n"; + wfProfileOut( $fname ); + return $difftext; + } + } + + if ( !$this->loadText() ) { + wfProfileOut( $fname ); + return false; + } + + $difftext = $this->generateDiffBody( $this->mOldtext, $this->mNewtext ); + + // Save to cache for 7 days + if ( $key !== false && $difftext !== false ) { + wfIncrStats( 'diff_cache_miss' ); + $wgMemc->set( $key, $difftext, 7*86400 ); + } else { + wfIncrStats( 'diff_uncacheable' ); + } + // Replace line numbers with the text in the user's language + if ( $difftext !== false ) { + $difftext = $this->localiseLineNumbers( $difftext ); + } + wfProfileOut( $fname ); + return $difftext; + } + + /** + * Generate a diff, no caching + * $otext and $ntext must be already segmented + */ + function generateDiffBody( $otext, $ntext ) { + global $wgExternalDiffEngine, $wgContLang; + $fname = 'DifferenceEngine::generateDiffBody'; + + $otext = str_replace( "\r\n", "\n", $otext ); + $ntext = str_replace( "\r\n", "\n", $ntext ); + + if ( $wgExternalDiffEngine == 'wikidiff' ) { + # For historical reasons, external diff engine expects + # input text to be HTML-escaped already + $otext = htmlspecialchars ( $wgContLang->segmentForDiff( $otext ) ); + $ntext = htmlspecialchars ( $wgContLang->segmentForDiff( $ntext ) ); + if( !function_exists( 'wikidiff_do_diff' ) ) { + dl('php_wikidiff.so'); + } + return $wgContLang->unsegementForDiff( wikidiff_do_diff( $otext, $ntext, 2 ) ); + } + + if ( $wgExternalDiffEngine == 'wikidiff2' ) { + # Better external diff engine, the 2 may some day be dropped + # This one does the escaping and segmenting itself + if ( !function_exists( 'wikidiff2_do_diff' ) ) { + wfProfileIn( "$fname-dl" ); + @dl('php_wikidiff2.so'); + wfProfileOut( "$fname-dl" ); + } + if ( function_exists( 'wikidiff2_do_diff' ) ) { + wfProfileIn( 'wikidiff2_do_diff' ); + $text = wikidiff2_do_diff( $otext, $ntext, 2 ); + wfProfileOut( 'wikidiff2_do_diff' ); + return $text; + } + } + if ( $wgExternalDiffEngine !== false ) { + # Diff via the shell + global $wgTmpDirectory; + $tempName1 = tempnam( $wgTmpDirectory, 'diff_' ); + $tempName2 = tempnam( $wgTmpDirectory, 'diff_' ); + + $tempFile1 = fopen( $tempName1, "w" ); + if ( !$tempFile1 ) { + wfProfileOut( $fname ); + return false; + } + $tempFile2 = fopen( $tempName2, "w" ); + if ( !$tempFile2 ) { + wfProfileOut( $fname ); + return false; + } + fwrite( $tempFile1, $otext ); + fwrite( $tempFile2, $ntext ); + fclose( $tempFile1 ); + fclose( $tempFile2 ); + $cmd = wfEscapeShellArg( $wgExternalDiffEngine, $tempName1, $tempName2 ); + wfProfileIn( "$fname-shellexec" ); + $difftext = wfShellExec( $cmd ); + wfProfileOut( "$fname-shellexec" ); + unlink( $tempName1 ); + unlink( $tempName2 ); + return $difftext; + } + + # Native PHP diff + $ota = explode( "\n", $wgContLang->segmentForDiff( $otext ) ); + $nta = explode( "\n", $wgContLang->segmentForDiff( $ntext ) ); + $diffs =& new Diff( $ota, $nta ); + $formatter =& new TableDiffFormatter(); + return $wgContLang->unsegmentForDiff( $formatter->format( $diffs ) ); + } + + + /** + * Replace line numbers with the text in the user's language + */ + function localiseLineNumbers( $text ) { + return preg_replace_callback( '/<!--LINE (\d+)-->/', + array( &$this, 'localiseLineNumbersCb' ), $text ); + } + + function localiseLineNumbersCb( $matches ) { + global $wgLang; + return wfMsgExt( 'lineno', array('parseinline'), $wgLang->formatNum( $matches[1] ) ); + } + + /** + * Add the header to a diff body + */ + function addHeader( $diff, $otitle, $ntitle ) { + $out = " + <table border='0' width='98%' cellpadding='0' cellspacing='4' class='diff'> + <tr> + <td colspan='2' width='50%' align='center' class='diff-otitle'>{$otitle}</td> + <td colspan='2' width='50%' align='center' class='diff-ntitle'>{$ntitle}</td> + </tr> + $diff + </table> + "; + return $out; + } + + /** + * Use specified text instead of loading from the database + */ + function setText( $oldText, $newText ) { + $this->mOldtext = $oldText; + $this->mNewtext = $newText; + $this->mTextLoaded = 2; + } + + /** + * Load revision metadata for the specified articles. If newid is 0, then compare + * the old article in oldid to the current article; if oldid is 0, then + * compare the current article to the immediately previous one (ignoring the + * value of newid). + * + * If oldid is false, leave the corresponding revision object set + * to false. This is impossible via ordinary user input, and is provided for + * API convenience. + */ + function loadRevisionData() { + global $wgLang; + if ( $this->mRevisionsLoaded ) { + return true; + } else { + // Whether it succeeds or fails, we don't want to try again + $this->mRevisionsLoaded = true; + } + + // Load the new revision object + if( $this->mNewid ) { + $this->mNewRev = Revision::newFromId( $this->mNewid ); + } else { + $this->mNewRev = Revision::newFromTitle( $this->mTitle ); + } + + if( is_null( $this->mNewRev ) ) { + return false; + } + + // Set assorted variables + $timestamp = $wgLang->timeanddate( $this->mNewRev->getTimestamp(), true ); + $this->mNewPage = $this->mNewRev->getTitle(); + if( $this->mNewRev->isCurrent() ) { + $newLink = $this->mNewPage->escapeLocalUrl(); + $this->mPagetitle = htmlspecialchars( wfMsg( 'currentrev' ) ); + $newEdit = $this->mNewPage->escapeLocalUrl( 'action=edit' ); + + $this->mNewtitle = "<strong><a href='$newLink'>{$this->mPagetitle}</a> ($timestamp)</strong>" + . " (<a href='$newEdit'>" . htmlspecialchars( wfMsg( 'editold' ) ) . "</a>)"; + + } else { + $newLink = $this->mNewPage->escapeLocalUrl( 'oldid=' . $this->mNewid ); + $newEdit = $this->mNewPage->escapeLocalUrl( 'action=edit&oldid=' . $this->mNewid ); + $this->mPagetitle = htmlspecialchars( wfMsg( 'revisionasof', $timestamp ) ); + + $this->mNewtitle = "<strong><a href='$newLink'>{$this->mPagetitle}</a></strong>" + . " (<a href='$newEdit'>" . htmlspecialchars( wfMsg( 'editold' ) ) . "</a>)"; + } + + // Load the old revision object + $this->mOldRev = false; + if( $this->mOldid ) { + $this->mOldRev = Revision::newFromId( $this->mOldid ); + } elseif ( $this->mOldid === 0 ) { + $rev = $this->mNewRev->getPrevious(); + if( $rev ) { + $this->mOldid = $rev->getId(); + $this->mOldRev = $rev; + } else { + // No previous revision; mark to show as first-version only. + $this->mOldid = false; + $this->mOldRev = false; + } + }/* elseif ( $this->mOldid === false ) leave mOldRev false; */ + + if( is_null( $this->mOldRev ) ) { + return false; + } + + if ( $this->mOldRev ) { + $this->mOldPage = $this->mOldRev->getTitle(); + + $t = $wgLang->timeanddate( $this->mOldRev->getTimestamp(), true ); + $oldLink = $this->mOldPage->escapeLocalUrl( 'oldid=' . $this->mOldid ); + $oldEdit = $this->mOldPage->escapeLocalUrl( 'action=edit&oldid=' . $this->mOldid ); + $this->mOldtitle = "<strong><a href='$oldLink'>" . htmlspecialchars( wfMsg( 'revisionasof', $t ) ) + . "</a></strong> (<a href='$oldEdit'>" . htmlspecialchars( wfMsg( 'editold' ) ) . "</a>)"; + } + + return true; + } + + /** + * Load the text of the revisions, as well as revision data. + */ + function loadText() { + if ( $this->mTextLoaded == 2 ) { + return true; + } else { + // Whether it succeeds or fails, we don't want to try again + $this->mTextLoaded = 2; + } + + if ( !$this->loadRevisionData() ) { + return false; + } + if ( $this->mOldRev ) { + // FIXME: permission tests + $this->mOldtext = $this->mOldRev->getText(); + if ( $this->mOldtext === false ) { + return false; + } + } + if ( $this->mNewRev ) { + $this->mNewtext = $this->mNewRev->getText(); + if ( $this->mNewtext === false ) { + return false; + } + } + return true; + } + + /** + * Load the text of the new revision, not the old one + */ + function loadNewText() { + if ( $this->mTextLoaded >= 1 ) { + return true; + } else { + $this->mTextLoaded = 1; + } + if ( !$this->loadRevisionData() ) { + return false; + } + $this->mNewtext = $this->mNewRev->getText(); + return true; + } + + +} + +// A PHP diff engine for phpwiki. (Taken from phpwiki-1.3.3) +// +// Copyright (C) 2000, 2001 Geoffrey T. Dairiki <dairiki@dairiki.org> +// You may copy this code freely under the conditions of the GPL. +// + +define('USE_ASSERTS', function_exists('assert')); + +/** + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class _DiffOp { + var $type; + var $orig; + var $closing; + + function reverse() { + trigger_error('pure virtual', E_USER_ERROR); + } + + function norig() { + return $this->orig ? sizeof($this->orig) : 0; + } + + function nclosing() { + return $this->closing ? sizeof($this->closing) : 0; + } +} + +/** + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class _DiffOp_Copy extends _DiffOp { + var $type = 'copy'; + + function _DiffOp_Copy ($orig, $closing = false) { + if (!is_array($closing)) + $closing = $orig; + $this->orig = $orig; + $this->closing = $closing; + } + + function reverse() { + return new _DiffOp_Copy($this->closing, $this->orig); + } +} + +/** + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class _DiffOp_Delete extends _DiffOp { + var $type = 'delete'; + + function _DiffOp_Delete ($lines) { + $this->orig = $lines; + $this->closing = false; + } + + function reverse() { + return new _DiffOp_Add($this->orig); + } +} + +/** + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class _DiffOp_Add extends _DiffOp { + var $type = 'add'; + + function _DiffOp_Add ($lines) { + $this->closing = $lines; + $this->orig = false; + } + + function reverse() { + return new _DiffOp_Delete($this->closing); + } +} + +/** + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class _DiffOp_Change extends _DiffOp { + var $type = 'change'; + + function _DiffOp_Change ($orig, $closing) { + $this->orig = $orig; + $this->closing = $closing; + } + + function reverse() { + return new _DiffOp_Change($this->closing, $this->orig); + } +} + + +/** + * Class used internally by Diff to actually compute the diffs. + * + * The algorithm used here is mostly lifted from the perl module + * Algorithm::Diff (version 1.06) by Ned Konz, which is available at: + * http://www.perl.com/CPAN/authors/id/N/NE/NEDKONZ/Algorithm-Diff-1.06.zip + * + * More ideas are taken from: + * http://www.ics.uci.edu/~eppstein/161/960229.html + * + * Some ideas are (and a bit of code) are from from analyze.c, from GNU + * diffutils-2.7, which can be found at: + * ftp://gnudist.gnu.org/pub/gnu/diffutils/diffutils-2.7.tar.gz + * + * closingly, some ideas (subdivision by NCHUNKS > 2, and some optimizations) + * are my own. + * + * Line length limits for robustness added by Tim Starling, 2005-08-31 + * + * @author Geoffrey T. Dairiki, Tim Starling + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class _DiffEngine +{ + function diff ($from_lines, $to_lines) { + $fname = '_DiffEngine::diff'; + wfProfileIn( $fname ); + + $n_from = sizeof($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++) { + $xhash[$this->_line_hash($from_lines[$xi])] = 1; + } + + for ($yi = $skip; $yi < $n_to - $endskip; $yi++) { + $line = $to_lines[$yi]; + if ( ($this->ychanged[$yi] = empty($xhash[$this->_line_hash($line)])) ) + continue; + $yhash[$this->_line_hash($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($yhash[$this->_line_hash($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); + } + wfProfileOut( $fname ); + return $edits; + } + + /** + * Returns the whole line if it's small enough, or the MD5 hash otherwise + */ + function _line_hash( $line ) { + if ( strlen( $line ) > MAX_DIFF_XREF_LENGTH ) { + return md5( $line ); + } else { + return $line; + } + } + + + /* Divide the Largest Common Subsequence (LCS) of the sequences + * [XOFF, XLIM) and [YOFF, YLIM) into NCHUNKS approximately equally + * sized segments. + * + * Returns (LCS, PTS). LCS is the length of the LCS. PTS is an + * array of NCHUNKS+1 (X, Y) indexes giving the diving points between + * sub sequences. The first sub-sequence is contained in [X0, X1), + * [Y0, Y1), the second in [X1, X2), [Y1, Y2) and so on. Note + * that (X0, Y0) == (XOFF, YOFF) and + * (X[NCHUNKS], Y[NCHUNKS]) == (XLIM, YLIM). + * + * This function assumes that the first lines of the specified portions + * of the two files do not match, and likewise that the last lines do not + * match. The caller must trim matching lines from the beginning and end + * of the portions it is going to specify. + */ + function _diag ($xoff, $xlim, $yoff, $ylim, $nchunks) { + $fname = '_DiffEngine::_diag'; + wfProfileIn( $fname ); + $flip = false; + + if ($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; $chunk++) { + wfProfileIn( "$fname-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]; + } + } + } + wfProfileOut( "$fname-chunk" ); + } + + $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); + + wfProfileOut( $fname ); + return array($this->lcs, $seps); + } + + function _lcs_pos ($ypos) { + $fname = '_DiffEngine::_lcs_pos'; + wfProfileIn( $fname ); + + $end = $this->lcs; + if ($end == 0 || $ypos > $this->seq[$end]) { + $this->seq[++$this->lcs] = $ypos; + $this->in_seq[$ypos] = 1; + wfProfileOut( $fname ); + 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; + wfProfileOut( $fname ); + 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) { + $fname = '_DiffEngine::_compareseq'; + wfProfileIn( $fname ); + + // Slide down the bottom initial diagonal. + while ($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; + } + } + wfProfileOut( $fname ); + } + + /* Adjust inserts/deletes of identical lines to join changes + * as much as possible. + * + * We do something when a run of changed lines include a + * line at one end and has an excluded, identical line at the other. + * We are free to choose which identical line is included. + * `compareseq' usually chooses the one at the beginning, + * but usually it is cleaner to consider the following identical line + * to be the "change". + * + * This is extracted verbatim from analyze.c (GNU diffutils-2.7). + */ + function _shift_boundaries ($lines, &$changed, $other_changed) { + $fname = '_DiffEngine::_shift_boundaries'; + wfProfileIn( $fname ); + $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]'); + } + } + wfProfileOut( $fname ); + } +} + +/** + * Class representing a 'diff' between two sequences of strings. + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +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 closing set of lines. + * + * This reconstructs the $to_lines parameter passed to the + * constructor. + * + * @return array The sequence of strings. + */ + function closing() { + $lines = array(); + + foreach ($this->edits as $edit) { + if ($edit->closing) + array_splice($lines, sizeof($lines), 0, $edit->closing); + } + return $lines; + } + + /** + * Check a Diff for validity. + * + * This is here only for debugging purposes. + */ + function _check ($from_lines, $to_lines) { + $fname = 'Diff::_check'; + wfProfileIn( $fname ); + if (serialize($from_lines) != serialize($this->orig())) + trigger_error("Reconstructed original doesn't match", E_USER_ERROR); + if (serialize($to_lines) != serialize($this->closing())) + trigger_error("Reconstructed closing 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->closing())) + trigger_error("Reversed closing 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); + wfProfileOut( $fname ); + } +} + +/** + * FIXME: bad name. + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +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) { + $fname = 'MappedDiff::MappedDiff'; + wfProfileIn( $fname ); + + assert(sizeof($from_lines) == sizeof($mapped_from_lines)); + assert(sizeof($to_lines) == sizeof($mapped_to_lines)); + + $this->Diff($mapped_from_lines, $mapped_to_lines); + + $xi = $yi = 0; + for ($i = 0; $i < sizeof($this->edits); $i++) { + $orig = &$this->edits[$i]->orig; + if (is_array($orig)) { + $orig = array_slice($from_lines, $xi, sizeof($orig)); + $xi += sizeof($orig); + } + + $closing = &$this->edits[$i]->closing; + if (is_array($closing)) { + $closing = array_slice($to_lines, $yi, sizeof($closing)); + $yi += sizeof($closing); + } + } + wfProfileOut( $fname ); + } +} + +/** + * A class to format Diffs + * + * This class formats the diff in classic diff format. + * It is intended that this class be customized via inheritance, + * to obtain fancier outputs. + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class DiffFormatter +{ + /** + * Number of leading context "lines" to preserve. + * + * This should be left at zero for this class, but subclasses + * may want to set this to other values. + */ + var $leading_context_lines = 0; + + /** + * Number of trailing context "lines" to preserve. + * + * This should be left at zero for this class, but subclasses + * may want to set this to other values. + */ + var $trailing_context_lines = 0; + + /** + * Format a diff. + * + * @param $diff object A Diff object. + * @return string The formatted output. + */ + function format($diff) { + $fname = 'DiffFormatter::format'; + wfProfileIn( $fname ); + + $xi = $yi = 1; + $block = false; + $context = array(); + + $nlead = $this->leading_context_lines; + $ntrail = $this->trailing_context_lines; + + $this->_start_diff(); + + foreach ($diff->edits as $edit) { + if ($edit->type == 'copy') { + if (is_array($block)) { + if (sizeof($edit->orig) <= $nlead + $ntrail) { + $block[] = $edit; + } + else{ + if ($ntrail) { + $context = array_slice($edit->orig, 0, $ntrail); + $block[] = new _DiffOp_Copy($context); + } + $this->_block($x0, $ntrail + $xi - $x0, + $y0, $ntrail + $yi - $y0, + $block); + $block = false; + } + } + $context = $edit->orig; + } + else { + if (! is_array($block)) { + $context = array_slice($context, sizeof($context) - $nlead); + $x0 = $xi - sizeof($context); + $y0 = $yi - sizeof($context); + $block = array(); + if ($context) + $block[] = new _DiffOp_Copy($context); + } + $block[] = $edit; + } + + if ($edit->orig) + $xi += sizeof($edit->orig); + if ($edit->closing) + $yi += sizeof($edit->closing); + } + + if (is_array($block)) + $this->_block($x0, $xi - $x0, + $y0, $yi - $y0, + $block); + + $end = $this->_end_diff(); + wfProfileOut( $fname ); + return $end; + } + + function _block($xbeg, $xlen, $ybeg, $ylen, &$edits) { + $fname = 'DiffFormatter::_block'; + wfProfileIn( $fname ); + $this->_start_block($this->_block_header($xbeg, $xlen, $ybeg, $ylen)); + foreach ($edits as $edit) { + if ($edit->type == 'copy') + $this->_context($edit->orig); + elseif ($edit->type == 'add') + $this->_added($edit->closing); + elseif ($edit->type == 'delete') + $this->_deleted($edit->orig); + elseif ($edit->type == 'change') + $this->_changed($edit->orig, $edit->closing); + else + trigger_error('Unknown edit type', E_USER_ERROR); + } + $this->_end_block(); + wfProfileOut( $fname ); + } + + function _start_diff() { + ob_start(); + } + + function _end_diff() { + $val = ob_get_contents(); + ob_end_clean(); + return $val; + } + + function _block_header($xbeg, $xlen, $ybeg, $ylen) { + if ($xlen > 1) + $xbeg .= "," . ($xbeg + $xlen - 1); + if ($ylen > 1) + $ybeg .= "," . ($ybeg + $ylen - 1); + + return $xbeg . ($xlen ? ($ylen ? 'c' : 'd') : 'a') . $ybeg; + } + + function _start_block($header) { + echo $header; + } + + function _end_block() { + } + + function _lines($lines, $prefix = ' ') { + foreach ($lines as $line) + echo "$prefix $line\n"; + } + + function _context($lines) { + $this->_lines($lines); + } + + function _added($lines) { + $this->_lines($lines, '>'); + } + function _deleted($lines) { + $this->_lines($lines, '<'); + } + + function _changed($orig, $closing) { + $this->_deleted($orig); + echo "---\n"; + $this->_added($closing); + } +} + + +/** + * Additions by Axel Boldt follow, partly taken from diff.php, phpwiki-1.3.3 + * + */ + +define('NBSP', ' '); // iso-8859-x non-breaking space. + +/** + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class _HWLDF_WordAccumulator { + function _HWLDF_WordAccumulator () { + $this->_lines = array(); + $this->_line = ''; + $this->_group = ''; + $this->_tag = ''; + } + + function _flushGroup ($new_tag) { + if ($this->_group !== '') { + if ($this->_tag == 'mark') + $this->_line .= '<span class="diffchange">' . + htmlspecialchars ( $this->_group ) . '</span>'; + else + $this->_line .= htmlspecialchars ( $this->_group ); + } + $this->_group = ''; + $this->_tag = $new_tag; + } + + function _flushLine ($new_tag) { + $this->_flushGroup($new_tag); + if ($this->_line != '') + array_push ( $this->_lines, $this->_line ); + else + # make empty lines visible by inserting an NBSP + array_push ( $this->_lines, NBSP ); + $this->_line = ''; + } + + function addWords ($words, $tag = '') { + if ($tag != $this->_tag) + $this->_flushGroup($tag); + + foreach ($words as $word) { + // new-line should only come as first char of word. + if ($word == '') + continue; + if ($word[0] == "\n") { + $this->_flushLine($tag); + $word = substr($word, 1); + } + assert(!strstr($word, "\n")); + $this->_group .= $word; + } + } + + function getLines() { + $this->_flushLine('~done'); + return $this->_lines; + } +} + +/** + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class WordLevelDiff extends MappedDiff +{ + function WordLevelDiff ($orig_lines, $closing_lines) { + $fname = 'WordLevelDiff::WordLevelDiff'; + wfProfileIn( $fname ); + + list ($orig_words, $orig_stripped) = $this->_split($orig_lines); + list ($closing_words, $closing_stripped) = $this->_split($closing_lines); + + $this->MappedDiff($orig_words, $closing_words, + $orig_stripped, $closing_stripped); + wfProfileOut( $fname ); + } + + function _split($lines) { + $fname = 'WordLevelDiff::_split'; + wfProfileIn( $fname ); + + $words = array(); + $stripped = array(); + $first = true; + foreach ( $lines as $line ) { + # If the line is too long, just pretend the entire line is one big word + # This prevents resource exhaustion problems + if ( $first ) { + $first = false; + } else { + $words[] = "\n"; + $stripped[] = "\n"; + } + if ( strlen( $line ) > MAX_DIFF_LINE ) { + $words[] = $line; + $stripped[] = $line; + } else { + if (preg_match_all('/ ( [^\S\n]+ | [0-9_A-Za-z\x80-\xff]+ | . ) (?: (?!< \n) [^\S\n])? /xs', + $line, $m)) + { + $words = array_merge( $words, $m[0] ); + $stripped = array_merge( $stripped, $m[1] ); + } + } + } + wfProfileOut( $fname ); + return array($words, $stripped); + } + + function orig () { + $fname = 'WordLevelDiff::orig'; + wfProfileIn( $fname ); + $orig = new _HWLDF_WordAccumulator; + + foreach ($this->edits as $edit) { + if ($edit->type == 'copy') + $orig->addWords($edit->orig); + elseif ($edit->orig) + $orig->addWords($edit->orig, 'mark'); + } + $lines = $orig->getLines(); + wfProfileOut( $fname ); + return $lines; + } + + function closing () { + $fname = 'WordLevelDiff::closing'; + wfProfileIn( $fname ); + $closing = new _HWLDF_WordAccumulator; + + foreach ($this->edits as $edit) { + if ($edit->type == 'copy') + $closing->addWords($edit->closing); + elseif ($edit->closing) + $closing->addWords($edit->closing, 'mark'); + } + $lines = $closing->getLines(); + wfProfileOut( $fname ); + return $lines; + } +} + +/** + * Wikipedia Table style diff formatter. + * @todo document + * @private + * @package MediaWiki + * @subpackage DifferenceEngine + */ +class TableDiffFormatter extends DiffFormatter +{ + function TableDiffFormatter() { + $this->leading_context_lines = 2; + $this->trailing_context_lines = 2; + } + + function _block_header( $xbeg, $xlen, $ybeg, $ylen ) { + $r = '<tr><td colspan="2" align="left"><strong><!--LINE '.$xbeg."--></strong></td>\n" . + '<td colspan="2" align="left"><strong><!--LINE '.$ybeg."--></strong></td></tr>\n"; + return $r; + } + + function _start_block( $header ) { + echo $header; + } + + function _end_block() { + } + + function _lines( $lines, $prefix=' ', $color='white' ) { + } + + # HTML-escape parameter before calling this + function addedLine( $line ) { + return "<td>+</td><td class='diff-addedline'>{$line}</td>"; + } + + # HTML-escape parameter before calling this + function deletedLine( $line ) { + return "<td>-</td><td class='diff-deletedline'>{$line}</td>"; + } + + # HTML-escape parameter before calling this + function contextLine( $line ) { + return "<td> </td><td class='diff-context'>{$line}</td>"; + } + + function emptyLine() { + return '<td colspan="2"> </td>'; + } + + function _added( $lines ) { + foreach ($lines as $line) { + echo '<tr>' . $this->emptyLine() . + $this->addedLine( htmlspecialchars ( $line ) ) . "</tr>\n"; + } + } + + function _deleted($lines) { + foreach ($lines as $line) { + echo '<tr>' . $this->deletedLine( htmlspecialchars ( $line ) ) . + $this->emptyLine() . "</tr>\n"; + } + } + + function _context( $lines ) { + foreach ($lines as $line) { + echo '<tr>' . + $this->contextLine( htmlspecialchars ( $line ) ) . + $this->contextLine( htmlspecialchars ( $line ) ) . "</tr>\n"; + } + } + + function _changed( $orig, $closing ) { + $fname = 'TableDiffFormatter::_changed'; + wfProfileIn( $fname ); + + $diff = new WordLevelDiff( $orig, $closing ); + $del = $diff->orig(); + $add = $diff->closing(); + + # Notice that WordLevelDiff returns HTML-escaped output. + # Hence, we will be calling addedLine/deletedLine without HTML-escaping. + + while ( $line = array_shift( $del ) ) { + $aline = array_shift( $add ); + echo '<tr>' . $this->deletedLine( $line ) . + $this->addedLine( $aline ) . "</tr>\n"; + } + foreach ($add as $line) { # If any leftovers + echo '<tr>' . $this->emptyLine() . + $this->addedLine( $line ) . "</tr>\n"; + } + wfProfileOut( $fname ); + } +} + +?> |