Update to MediaWiki 1.21.1

3 files changed, 197 insertions, 78 deletions

diff --git a/includes/diff/DairikiDiff.php b/includes/diff/DairikiDiff.php
index 72eb5d3c..94ffc066 100644
--- a/includes/diff/DairikiDiff.php
+++ b/includes/diff/DairikiDiff.php
@@ -5,6 +5,21 @@
  * Copyright © 2000, 2001 Geoffrey T. Dairiki <dairiki@dairiki.org>
  * You may copy this code freely under the conditions of the GPL.
  *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
  * @file
  * @ingroup DifferenceEngine
  * @defgroup DifferenceEngine DifferenceEngine
@@ -28,14 +43,14 @@ class _DiffOp {
 	 * @return int
 	 */
 	function norig() {
-		return $this->orig ? sizeof( $this->orig ) : 0;
+		return $this->orig ? count( $this->orig ) : 0;
 	}
 
 	/**
 	 * @return int
 	 */
 	function nclosing() {
-		return $this->closing ? sizeof( $this->closing ) : 0;
+		return $this->closing ? count( $this->closing ) : 0;
 	}
 }
 
@@ -152,7 +167,7 @@ class _DiffOp_Change extends _DiffOp {
  */
 class _DiffEngine {
 
-	const MAX_XREF_LENGTH =  10000;
+	const MAX_XREF_LENGTH = 10000;
 
 	protected $xchanged, $ychanged;
 
@@ -179,8 +194,8 @@ class _DiffEngine {
 		$this->_shift_boundaries( $to_lines, $this->ychanged, $this->xchanged );
 
 		// Compute the edit operations.
-		$n_from = sizeof( $from_lines );
-		$n_to = sizeof( $to_lines );
+		$n_from = count( $from_lines );
+		$n_to = count( $to_lines );
 
 		$edits = array();
 		$xi = $yi = 0;
@@ -206,7 +221,7 @@ class _DiffEngine {
 			}
 
 			$add = array();
-			while ( $yi < $n_to && $this->ychanged[$yi] )  {
+			while ( $yi < $n_to && $this->ychanged[$yi] ) {
 				$add[] = $to_lines[$yi++];
 			}
 
@@ -239,8 +254,8 @@ class _DiffEngine {
 			unset( $wikidiff3 );
 		} else {
 			// old diff
-			$n_from = sizeof( $from_lines );
-			$n_to = sizeof( $to_lines );
+			$n_from = count( $from_lines );
+			$n_to = count( $to_lines );
 			$this->xchanged = $this->ychanged = array();
 			$this->xv = $this->yv = array();
 			$this->xind = $this->yind = array();
@@ -288,7 +303,7 @@ class _DiffEngine {
 			}
 
 			// Find the LCS.
-			$this->_compareseq( 0, sizeof( $this->xv ), 0, sizeof( $this->yv ) );
+			$this->_compareseq( 0, count( $this->xv ), 0, count( $this->yv ) );
 		}
 		wfProfileOut( __METHOD__ );
 	}
@@ -311,7 +326,7 @@ class _DiffEngine {
 	 * [XOFF, XLIM) and [YOFF, YLIM) into NCHUNKS approximately equally
 	 * sized segments.
 	 *
-	 * Returns (LCS, PTS).	LCS is the length of the LCS. PTS is an
+	 * 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
@@ -476,8 +491,7 @@ class _DiffEngine {
 			// $nchunks = sqrt(min($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 );
+			list ( $lcs, $seps ) = $this->_diag( $xoff, $xlim, $yoff, $ylim, $nchunks );
 		}
 
 		if ( $lcs == 0 ) {
@@ -518,9 +532,9 @@ class _DiffEngine {
 		$i = 0;
 		$j = 0;
 
-		assert( 'sizeof($lines) == sizeof($changed)' );
-		$len = sizeof( $lines );
-		$other_len = sizeof( $other_changed );
+		assert( 'count($lines) == count($changed)' );
+		$len = count( $lines );
+		$other_len = count( $other_changed );
 
 		while ( 1 ) {
 			/*
@@ -698,7 +712,7 @@ class Diff {
 		$lcs = 0;
 		foreach ( $this->edits as $edit ) {
 			if ( $edit->type == 'copy' ) {
-				$lcs += sizeof( $edit->orig );
+				$lcs += count( $edit->orig );
 			}
 		}
 		return $lcs;
@@ -717,7 +731,7 @@ class Diff {
 
 		foreach ( $this->edits as $edit ) {
 			if ( $edit->orig ) {
-				array_splice( $lines, sizeof( $lines ), 0, $edit->orig );
+				array_splice( $lines, count( $lines ), 0, $edit->orig );
 			}
 		}
 		return $lines;
@@ -736,7 +750,7 @@ class Diff {
 
 		foreach ( $this->edits as $edit ) {
 			if ( $edit->closing ) {
-				array_splice( $lines, sizeof( $lines ), 0, $edit->closing );
+				array_splice( $lines, count( $lines ), 0, $edit->closing );
 			}
 		}
 		return $lines;
@@ -766,7 +780,6 @@ class Diff {
 			trigger_error( "Reversed closing doesn't match", E_USER_ERROR );
 		}
 
-
 		$prevtype = 'none';
 		foreach ( $this->edits as $edit ) {
 			if ( $prevtype == $edit->type ) {
@@ -814,23 +827,23 @@ class MappedDiff extends Diff {
 		$mapped_from_lines, $mapped_to_lines ) {
 		wfProfileIn( __METHOD__ );
 
-		assert( 'sizeof( $from_lines ) == sizeof( $mapped_from_lines )' );
-		assert( 'sizeof( $to_lines ) == sizeof( $mapped_to_lines )' );
+		assert( 'count( $from_lines ) == count( $mapped_from_lines )' );
+		assert( 'count( $to_lines ) == count( $mapped_to_lines )' );
 
 		parent::__construct( $mapped_from_lines, $mapped_to_lines );
 
 		$xi = $yi = 0;
-		for ( $i = 0; $i < sizeof( $this->edits ); $i++ ) {
+		for ( $i = 0; $i < count( $this->edits ); $i++ ) {
 			$orig = &$this->edits[$i]->orig;
 			if ( is_array( $orig ) ) {
-				$orig = array_slice( $from_lines, $xi, sizeof( $orig ) );
-				$xi += sizeof( $orig );
+				$orig = array_slice( $from_lines, $xi, count( $orig ) );
+				$xi += count( $orig );
 			}
 
 			$closing = &$this->edits[$i]->closing;
 			if ( is_array( $closing ) ) {
-				$closing = array_slice( $to_lines, $yi, sizeof( $closing ) );
-				$yi += sizeof( $closing );
+				$closing = array_slice( $to_lines, $yi, count( $closing ) );
+				$yi += count( $closing );
 			}
 		}
 		wfProfileOut( __METHOD__ );
@@ -885,7 +898,7 @@ class DiffFormatter {
 		foreach ( $diff->edits as $edit ) {
 			if ( $edit->type == 'copy' ) {
 				if ( is_array( $block ) ) {
-					if ( sizeof( $edit->orig ) <= $nlead + $ntrail ) {
+					if ( count( $edit->orig ) <= $nlead + $ntrail ) {
 						$block[] = $edit;
 					} else {
 						if ( $ntrail ) {
@@ -901,9 +914,9 @@ class DiffFormatter {
 				$context = $edit->orig;
 			} else {
 				if ( !is_array( $block ) ) {
-					$context = array_slice( $context, sizeof( $context ) - $nlead );
-					$x0 = $xi - sizeof( $context );
-					$y0 = $yi - sizeof( $context );
+					$context = array_slice( $context, count( $context ) - $nlead );
+					$x0 = $xi - count( $context );
+					$y0 = $yi - count( $context );
 					$block = array();
 					if ( $context ) {
 						$block[] = new _DiffOp_Copy( $context );
@@ -913,10 +926,10 @@ class DiffFormatter {
 			}
 
 			if ( $edit->orig ) {
-				$xi += sizeof( $edit->orig );
+				$xi += count( $edit->orig );
 			}
 			if ( $edit->closing ) {
-				$yi += sizeof( $edit->closing );
+				$yi += count( $edit->closing );
 			}
 		}
 
@@ -1350,7 +1363,7 @@ class TableDiffFormatter extends DiffFormatter {
 	 */
 	function _block_header( $xbeg, $xlen, $ybeg, $ylen ) {
 		$r = '<tr><td colspan="2" class="diff-lineno"><!--LINE ' . $xbeg . "--></td>\n" .
-		  '<td colspan="2" class="diff-lineno"><!--LINE ' . $ybeg . "--></td></tr>\n";
+			'<td colspan="2" class="diff-lineno"><!--LINE ' . $ybeg . "--></td></tr>\n";
 		return $r;
 	}
 
diff --git a/includes/diff/DifferenceEngine.php b/includes/diff/DifferenceEngine.php
index c7156fb2..0f3c77ff 100644
--- a/includes/diff/DifferenceEngine.php
+++ b/includes/diff/DifferenceEngine.php
@@ -38,7 +38,10 @@ class DifferenceEngine extends ContextSource {
 	 * @private
 	 */
 	var $mOldid, $mNewid;
-	var $mOldtext, $mNewtext;
+	/**
+	 * @var Content
+	 */
+	var $mOldContent, $mNewContent;
 	protected $mDiffLang;
 
 	/**
@@ -77,7 +80,7 @@ class DifferenceEngine extends ContextSource {
 	 * Constructor
 	 * @param $context IContextSource context to use, anything else will be ignored
 	 * @param $old Integer old ID we want to show and diff with.
-	 * @param $new String either 'prev' or 'next'.
+	 * @param string $new either 'prev' or 'next'.
 	 * @param $rcid Integer ??? FIXME (default 0)
 	 * @param $refreshCache boolean If set, refreshes the diff cache
 	 * @param $unhide boolean If set, allow viewing deleted revs
@@ -149,7 +152,7 @@ class DifferenceEngine extends ContextSource {
 	function deletedLink( $id ) {
 		if ( $this->getUser()->isAllowed( 'deletedhistory' ) ) {
 			$dbr = wfGetDB( DB_SLAVE );
-			$row = $dbr->selectRow('archive', '*',
+			$row = $dbr->selectRow( 'archive', '*',
 				array( 'ar_rev_id' => $id ),
 				__METHOD__ );
 			if ( $row ) {
@@ -224,6 +227,10 @@ class DifferenceEngine extends ContextSource {
 		# we'll use the application/x-external-editor interface to call
 		# an external diff tool like kompare, kdiff3, etc.
 		if ( ExternalEdit::useExternalEngine( $this->getContext(), 'diff' ) ) {
+			//TODO: come up with a good solution for non-text content here.
+			//      at least, the content format needs to be passed to the client somehow.
+			//      Currently, action=raw will just fail for non-text content.
+
 			$urls = array(
 				'File' => array( 'Extension' => 'wiki', 'URL' =>
 					# This should be mOldPage, but it may not be set, see below.
@@ -260,6 +267,8 @@ class DifferenceEngine extends ContextSource {
 		$deleted = $suppressed = false;
 		$allowed = $this->mNewRev->userCan( Revision::DELETED_TEXT, $user );
 
+		$revisionTools = array();
+
 		# mOldRev 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.
@@ -287,12 +296,14 @@ class DifferenceEngine extends ContextSource {
 
 			if ( $samePage && $this->mNewPage->quickUserCan( 'edit', $user ) ) {
 				if ( $this->mNewRev->isCurrent() && $this->mNewPage->userCan( 'rollback', $user ) ) {
-					$out->preventClickjacking();
-					$rollback = '&#160;&#160;&#160;' . Linker::generateRollback( $this->mNewRev, $this->getContext() );
+					$rollbackLink = Linker::generateRollback( $this->mNewRev, $this->getContext() );
+					if ( $rollbackLink ) {
+						$out->preventClickjacking();
+						$rollback = '&#160;&#160;&#160;' . $rollbackLink;
+					}
 				}
 				if ( !$this->mOldRev->isDeleted( Revision::DELETED_TEXT ) && !$this->mNewRev->isDeleted( Revision::DELETED_TEXT ) ) {
-					$undoLink = ' ' . $this->msg( 'parentheses' )->rawParams(
-						Html::element( 'a', array(
+					$undoLink = Html::element( 'a', array(
 							'href' => $this->mNewPage->getLocalUrl( array(
 								'action' => 'edit',
 								'undoafter' => $this->mOldid,
@@ -300,7 +311,8 @@ class DifferenceEngine extends ContextSource {
 							'title' => Linker::titleAttrib( 'undo' )
 						),
 						$this->msg( 'editundo' )->text()
-					) )->escaped();
+					);
+					$revisionTools[] = $undoLink;
 				}
 			}
 
@@ -366,7 +378,15 @@ class DifferenceEngine extends ContextSource {
 
 		# Handle RevisionDelete links...
 		$rdel = $this->revisionDeleteLink( $this->mNewRev );
-		$newRevisionHeader = $this->getRevisionHeader( $this->mNewRev, 'complete' ) . $undoLink;
+
+		# Allow extensions to define their own revision tools
+		wfRunHooks( 'DiffRevisionTools', array( $this->mNewRev, &$revisionTools ) );
+		$formattedRevisionTools = array();
+		// Put each one in parentheses (poor man's button)
+		foreach ( $revisionTools as $tool ) {
+			$formattedRevisionTools[] = $this->msg( 'parentheses' )->rawParams( $tool )->escaped();
+		}
+		$newRevisionHeader = $this->getRevisionHeader( $this->mNewRev, 'complete' ) . ' ' . implode( ' ', $formattedRevisionTools );
 
 		$newHeader = '<div id="mw-diff-ntitle1"><strong>' . $newRevisionHeader . '</strong></div>' .
 			'<div id="mw-diff-ntitle2">' . Linker::revUserTools( $this->mNewRev, !$this->unhide ) .
@@ -417,8 +437,8 @@ class DifferenceEngine extends ContextSource {
 	/**
 	 * Get a link to mark the change as patrolled, or '' if there's either no
 	 * revision to patrol or the user is not allowed to to it.
-	 * Side effect: this method will call OutputPage::preventClickjacking()
-	 * when a link is builded.
+	 * Side effect: When the patrol link is build, this method will call
+	 * OutputPage::preventClickjacking() and load mediawiki.page.patrol.ajax.
 	 *
 	 * @return String
 	 */
@@ -459,6 +479,8 @@ class DifferenceEngine extends ContextSource {
 				// Build the link
 				if ( $rcid ) {
 					$this->getOutput()->preventClickjacking();
+					$this->getOutput()->addModules( 'mediawiki.page.patrol.ajax' );
+
 					$token = $this->getUser()->getEditToken( $rcid );
 					$this->mMarkPatrolledLink = ' <span class="patrollink">[' . Linker::linkKnown(
 						$this->mNewPage,
@@ -510,19 +532,23 @@ class DifferenceEngine extends ContextSource {
 			$out->setRevisionTimestamp( $this->mNewRev->getTimestamp() );
 			$out->setArticleFlag( true );
 
+			// NOTE: only needed for B/C: custom rendering of JS/CSS via hook
 			if ( $this->mNewPage->isCssJsSubpage() || $this->mNewPage->isCssOrJsPage() ) {
 				// Stolen from Article::view --AG 2007-10-11
 				// Give hooks a chance to customise the output
 				// @TODO: standardize this crap into one function
-				if ( wfRunHooks( 'ShowRawCssJs', array( $this->mNewtext, $this->mNewPage, $out ) ) ) {
-					// Wrap the whole lot in a <pre> and don't parse
-					$m = array();
-					preg_match( '!\.(css|js)$!u', $this->mNewPage->getText(), $m );
-					$out->addHTML( "<pre class=\"mw-code mw-{$m[1]}\" dir=\"ltr\">\n" );
-					$out->addHTML( htmlspecialchars( $this->mNewtext ) );
-					$out->addHTML( "\n</pre>\n" );
+				if ( ContentHandler::runLegacyHooks( 'ShowRawCssJs', array( $this->mNewContent, $this->mNewPage, $out ) ) ) {
+					// NOTE: deprecated hook, B/C only
+					// use the content object's own rendering
+					$cnt = $this->mNewRev->getContent();
+					$po = $cnt ? $cnt->getParserOutput( $this->mNewRev->getTitle(), $this->mNewRev->getId() ) : null;
+					$txt = $po ? $po->getText() : '';
+					$out->addHTML( $txt );
 				}
-			} elseif ( !wfRunHooks( 'ArticleViewCustom', array( $this->mNewtext, $this->mNewPage, $out ) ) ) {
+			} elseif( !wfRunHooks( 'ArticleContentViewCustom', array( $this->mNewContent, $this->mNewPage, $out ) ) ) {
+				// Handled by extension
+			} elseif( !ContentHandler::runLegacyHooks( 'ArticleViewCustom', array( $this->mNewContent, $this->mNewPage, $out ) ) ) {
+				// NOTE: deprecated hook, B/C only
 				// Handled by extension
 			} else {
 				// Normal page
@@ -536,16 +562,21 @@ class DifferenceEngine extends ContextSource {
 					$wikiPage = WikiPage::factory( $this->mNewPage );
 				}
 
-				$parserOptions = $wikiPage->makeParserOptions( $this->getContext() );
+				$parserOutput = $this->getParserOutput( $wikiPage, $this->mNewRev );
 
-				if ( !$this->mNewRev->isCurrent() ) {
-					$parserOptions->setEditSection( false );
-				}
+				# Also try to load it as a redirect
+				$rt = $this->mNewContent ? $this->mNewContent->getRedirectTarget() : null;
 
-				$parserOutput = $wikiPage->getParserOutput( $parserOptions, $this->mNewid );
+				if ( $rt ) {
+					$article = Article::newFromTitle( $this->mNewPage, $this->getContext() );
+					$out->addHTML( $article->viewRedirect( $rt ) );
 
-				# WikiPage::getParserOutput() should not return false, but just in case
-				if( $parserOutput ) {
+					# WikiPage::getParserOutput() should not return false, but just in case
+					if ( $parserOutput ) {
+						# Show categories etc.
+						$out->addParserOutputNoText( $parserOutput );
+					}
+				} else if ( $parserOutput ) {
 					$out->addParserOutput( $parserOutput );
 				}
 			}
@@ -556,6 +587,17 @@ class DifferenceEngine extends ContextSource {
 		wfProfileOut( __METHOD__ );
 	}
 
+	protected function getParserOutput( WikiPage $page, Revision $rev ) {
+		$parserOptions = $page->makeParserOptions( $this->getContext() );
+
+		if ( !$rev->isCurrent() || !$rev->getTitle()->quickUserCan( "edit" ) ) {
+			$parserOptions->setEditSection( false );
+		}
+
+		$parserOutput = $page->getParserOutput( $parserOptions, $rev->getId() );
+		return $parserOutput;
+	}
+
 	/**
 	 * Get the diff text, send it to the OutputPage object
 	 * Returns false if the diff could not be generated, otherwise returns true
@@ -584,9 +626,9 @@ class DifferenceEngine extends ContextSource {
 	/**
 	 * Get complete diff table, including header
 	 *
-	 * @param $otitle Title: old title
-	 * @param $ntitle Title: new title
-	 * @param $notice String: HTML between diff header and body
+	 * @param string|bool $otitle Header for old text or false
+	 * @param string|bool $ntitle Header for new text or false
+	 * @param string $notice HTML between diff header and body
 	 * @return mixed
 	 */
 	function getDiff( $otitle, $ntitle, $notice = '' ) {
@@ -652,7 +694,7 @@ class DifferenceEngine extends ContextSource {
 			return false;
 		}
 
-		$difftext = $this->generateDiffBody( $this->mOldtext, $this->mNewtext );
+		$difftext = $this->generateContentDiffBody( $this->mOldContent, $this->mNewContent );
 
 		// Save to cache for 7 days
 		if ( !wfRunHooks( 'AbortDiffCache', array( &$this ) ) ) {
@@ -690,13 +732,64 @@ class DifferenceEngine extends ContextSource {
 	}
 
 	/**
+	 * Generate a diff, no caching.
+	 *
+	 * This implementation uses generateTextDiffBody() to generate a diff based on the default
+	 * serialization of the given Content objects. This will fail if $old or $new are not
+	 * instances of TextContent.
+	 *
+	 * Subclasses may override this to provide a different rendering for the diff,
+	 * perhaps taking advantage of the content's native form. This is required for all content
+	 * models that are not text based.
+	 *
+	 * @param $old Content: old content
+	 * @param $new Content: new content
+	 *
+	 * @return bool|string
+	 * @since 1.21
+	 * @throws MWException if $old or $new are not instances of TextContent.
+	 */
+	function generateContentDiffBody( Content $old, Content $new ) {
+		if ( !( $old instanceof TextContent ) ) {
+			throw new MWException( "Diff not implemented for " . get_class( $old ) . "; "
+					. "override generateContentDiffBody to fix this." );
+		}
+
+		if ( !( $new instanceof TextContent ) ) {
+			throw new MWException( "Diff not implemented for " . get_class( $new ) . "; "
+				. "override generateContentDiffBody to fix this." );
+		}
+
+		$otext = $old->serialize();
+		$ntext = $new->serialize();
+
+		return $this->generateTextDiffBody( $otext, $ntext );
+	}
+
+	/**
 	 * Generate a diff, no caching
 	 *
-	 * @param $otext String: old text, must be already segmented
-	 * @param $ntext String: new text, must be already segmented
+	 * @param string $otext old text, must be already segmented
+	 * @param string $ntext new text, must be already segmented
 	 * @return bool|string
+	 * @deprecated since 1.21, use generateContentDiffBody() instead!
 	 */
 	function generateDiffBody( $otext, $ntext ) {
+		ContentHandler::deprecated( __METHOD__, "1.21" );
+
+		return $this->generateTextDiffBody( $otext, $ntext );
+	}
+
+	/**
+	 * Generate a diff, no caching
+	 *
+	 * @todo move this to TextDifferenceEngine, make DifferenceEngine abstract. At some point.
+	 *
+	 * @param string $otext old text, must be already segmented
+	 * @param string $ntext new text, must be already segmented
+	 * @return bool|string
+	 */
+	function generateTextDiffBody( $otext, $ntext ) {
 		global $wgExternalDiffEngine, $wgContLang;
 
 		wfProfileIn( __METHOD__ );
@@ -804,7 +897,6 @@ class DifferenceEngine extends ContextSource {
 		return $this->msg( 'lineno' )->numParams( $matches[1] )->escaped();
 	}
 
-
 	/**
 	 * If there are revisions between the ones being compared, return a note saying so.
 	 * @return string
@@ -855,11 +947,11 @@ class DifferenceEngine extends ContextSource {
 	 * Get a header for a specified revision.
 	 *
 	 * @param $rev Revision
-	 * @param $complete String: 'complete' to get the header wrapped depending
+	 * @param string $complete 'complete' to get the header wrapped depending
 	 *        the visibility of the revision and a link to edit the page.
 	 * @return String HTML fragment
 	 */
-	private function getRevisionHeader( Revision $rev, $complete = '' ) {
+	protected function getRevisionHeader( Revision $rev, $complete = '' ) {
 		$lang = $this->getLanguage();
 		$user = $this->getUser();
 		$revtimestamp = $rev->getTimestamp();
@@ -951,10 +1043,25 @@ class DifferenceEngine extends ContextSource {
 
 	/**
 	 * Use specified text instead of loading from the database
+	 * @deprecated since 1.21, use setContent() instead.
 	 */
 	function setText( $oldText, $newText ) {
-		$this->mOldtext = $oldText;
-		$this->mNewtext = $newText;
+		ContentHandler::deprecated( __METHOD__, "1.21" );
+
+		$oldContent = ContentHandler::makeContent( $oldText, $this->getTitle() );
+		$newContent = ContentHandler::makeContent( $newText, $this->getTitle() );
+
+		$this->setContent( $oldContent, $newContent );
+	}
+
+	/**
+	 * Use specified text instead of loading from the database
+	 * @since 1.21
+	 */
+	function setContent( Content $oldContent, Content $newContent ) {
+		$this->mOldContent = $oldContent;
+		$this->mNewContent = $newContent;
+
 		$this->mTextLoaded = 2;
 		$this->mRevisionsLoaded = true;
 	}
@@ -1082,14 +1189,14 @@ class DifferenceEngine extends ContextSource {
 			return false;
 		}
 		if ( $this->mOldRev ) {
-			$this->mOldtext = $this->mOldRev->getText( Revision::FOR_THIS_USER );
-			if ( $this->mOldtext === false ) {
+			$this->mOldContent = $this->mOldRev->getContent( Revision::FOR_THIS_USER, $this->getUser() );
+			if ( $this->mOldContent === null ) {
 				return false;
 			}
 		}
 		if ( $this->mNewRev ) {
-			$this->mNewtext = $this->mNewRev->getText( Revision::FOR_THIS_USER );
-			if ( $this->mNewtext === false ) {
+			$this->mNewContent = $this->mNewRev->getContent( Revision::FOR_THIS_USER, $this->getUser() );
+			if ( $this->mNewContent === null ) {
 				return false;
 			}
 		}
@@ -1110,7 +1217,7 @@ class DifferenceEngine extends ContextSource {
 		if ( !$this->loadRevisionData() ) {
 			return false;
 		}
-		$this->mNewtext = $this->mNewRev->getText( Revision::FOR_THIS_USER );
+		$this->mNewContent = $this->mNewRev->getContent( Revision::FOR_THIS_USER, $this->getUser() );
 		return true;
 	}
 }
diff --git a/includes/diff/WikiDiff3.php b/includes/diff/WikiDiff3.php
index 66727445..ea6f6e5d 100644
--- a/includes/diff/WikiDiff3.php
+++ b/includes/diff/WikiDiff3.php
@@ -29,7 +29,7 @@
  * (http://citeseer.ist.psu.edu/myers86ond.html) with range compression (see Wu et al.'s
  * "An O(NP) Sequence Comparison Algorithm").
  *
- * This implementation supports an upper bound on the excution time.
+ * This implementation supports an upper bound on the execution time.
  *
  * Complexity: O((M + N)D) worst case time, O(M + N + D^2) expected time, O(M + N) space
  *
@@ -64,7 +64,7 @@ class WikiDiff3 {
 
 	public function diff( /*array*/ $from, /*array*/ $to ) {
 		// remember initial lengths
-		$m = sizeof( $from );
+		$m = count( $from );
 		$n = count( $to );
 
 		$this->heuristicUsed = false;
@@ -490,7 +490,6 @@ class WikiDiff3 {
 
 		$temp = array( 0, 0, 0 );
 
-
 		$max_progress = array_fill( 0, ceil( max( $forward_end_diag - $forward_start_diag,
 				$backward_end_diag - $backward_start_diag ) / 2 ), $temp );
 		$num_progress = 0; // the 1st entry is current, it is initialized