EnhancedChangesList.php

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<?php
class EnhancedChangesList extends ChangesList {
 
    protected $cacheEntryFactory;
 
    protected $rc_cache;
 
    protected $templateParser;
 
    public function __construct( $obj, array $filterGroups = [] ) {
        if ( $obj instanceof Skin ) {
            // @todo: deprecate constructing with Skin
            $context = $obj->getContext();
        } else {
            if ( !$obj instanceof IContextSource ) {
                throw new MWException( 'EnhancedChangesList must be constructed with a '
                    . 'context source or skin.' );
            }
 
            $context = $obj;
        }
 
        parent::__construct( $context, $filterGroups );
 
        // message is set by the parent ChangesList class
        $this->cacheEntryFactory = new RCCacheEntryFactory(
            $context,
            $this->message,
            $this->linkRenderer
        );
        $this->templateParser = new TemplateParser();
    }
 
    public function beginRecentChangesList() {
        $this->rc_cache = [];
        $this->rcMoveIndex = 0;
        $this->rcCacheIndex = 0;
        $this->lastdate = '';
        $this->rclistOpen = false;
        $this->getOutput()->addModuleStyles( [
            'mediawiki.special.changeslist',
            'mediawiki.special.changeslist.enhanced',
        ] );
        $this->getOutput()->addModules( [
            'jquery.makeCollapsible',
            'mediawiki.icon',
        ] );
 
        return '<div class="mw-changeslist">';
    }
 
    public function recentChangesLine( &$rc, $watched = false, $linenumber = null ) {
        $date = $this->getLanguage()->userDate(
            $rc->mAttribs['rc_timestamp'],
            $this->getUser()
        );
        if ( $this->lastdate === '' ) {
            $this->lastdate = $date;
        }
 
        $ret = '';
 
        # If it's a new day, flush the cache and update $this->lastdate
        if ( $date !== $this->lastdate ) {
            # Process current cache (uses $this->lastdate to generate a heading)
            $ret = $this->recentChangesBlock();
            $this->rc_cache = [];
            $this->lastdate = $date;
        }
 
        $cacheEntry = $this->cacheEntryFactory->newFromRecentChange( $rc, $watched );
        $this->addCacheEntry( $cacheEntry );
 
        return $ret;
    }
 
    protected function addCacheEntry( RCCacheEntry $cacheEntry ) {
        $cacheGroupingKey = $this->makeCacheGroupingKey( $cacheEntry );
 
        if ( !isset( $this->rc_cache[$cacheGroupingKey] ) ) {
            $this->rc_cache[$cacheGroupingKey] = [];
        }
 
        array_push( $this->rc_cache[$cacheGroupingKey], $cacheEntry );
    }
 
    protected function makeCacheGroupingKey( RCCacheEntry $cacheEntry ) {
        $title = $cacheEntry->getTitle();
        $cacheGroupingKey = $title->getPrefixedDBkey();
 
        $type = $cacheEntry->mAttribs['rc_type'];
 
        if ( $type == RC_LOG ) {
            // Group by log type
            $cacheGroupingKey = SpecialPage::getTitleFor(
                'Log',
                $cacheEntry->mAttribs['rc_log_type']
            )->getPrefixedDBkey();
        }
 
        return $cacheGroupingKey;
    }
 
    protected function recentChangesBlockGroup( $block ) {
        $recentChangesFlags = $this->getConfig()->get( 'RecentChangesFlags' );
 
        # Add the namespace and title of the block as part of the class
        $tableClasses = [ 'mw-collapsible', 'mw-collapsed', 'mw-enhanced-rc', 'mw-changeslist-line' ];
        if ( $block[0]->mAttribs['rc_log_type'] ) {
            # Log entry
            $tableClasses[] = 'mw-changeslist-log';
            $tableClasses[] = Sanitizer::escapeClass( 'mw-changeslist-log-'
                . $block[0]->mAttribs['rc_log_type'] );
        } else {
            $tableClasses[] = 'mw-changeslist-edit';
            $tableClasses[] = Sanitizer::escapeClass( 'mw-changeslist-ns'
                . $block[0]->mAttribs['rc_namespace'] . '-' . $block[0]->mAttribs['rc_title'] );
        }
        if ( $block[0]->watched
            && $block[0]->mAttribs['rc_timestamp'] >= $block[0]->watched
        ) {
            $tableClasses[] = 'mw-changeslist-line-watched';
        } else {
            $tableClasses[] = 'mw-changeslist-line-not-watched';
        }
 
        # Collate list of users
        $userlinks = [];
        # Other properties
        $curId = 0;
        # Some catalyst variables...
        $namehidden = true;
        $allLogs = true;
        $RCShowChangedSize = $this->getConfig()->get( 'RCShowChangedSize' );
 
        # Default values for RC flags
        $collectedRcFlags = [];
        foreach ( $recentChangesFlags as $key => $value ) {
            $flagGrouping = ( isset( $recentChangesFlags[$key]['grouping'] ) ?
                    $recentChangesFlags[$key]['grouping'] : 'any' );
            switch ( $flagGrouping ) {
                case 'all':
                    $collectedRcFlags[$key] = true;
                    break;
                case 'any':
                    $collectedRcFlags[$key] = false;
                    break;
                default:
                    throw new DomainException( "Unknown grouping type \"{$flagGrouping}\"" );
            }
        }
        foreach ( $block as $rcObj ) {
            // If all log actions to this page were hidden, then don't
            // give the name of the affected page for this block!
            if ( !$this->isDeleted( $rcObj, LogPage::DELETED_ACTION ) ) {
                $namehidden = false;
            }
            $u = $rcObj->userlink;
            if ( !isset( $userlinks[$u] ) ) {
                $userlinks[$u] = 0;
            }
            if ( $rcObj->mAttribs['rc_type'] != RC_LOG ) {
                $allLogs = false;
            }
            # Get the latest entry with a page_id and oldid
            # since logs may not have these.
            if ( !$curId && $rcObj->mAttribs['rc_cur_id'] ) {
                $curId = $rcObj->mAttribs['rc_cur_id'];
            }
 
            $userlinks[$u]++;
        }
 
        # Sort the list and convert to text
        krsort( $userlinks );
        asort( $userlinks );
        $users = [];
        foreach ( $userlinks as $userlink => $count ) {
            $text = $userlink;
            $text .= $this->getLanguage()->getDirMark();
            if ( $count > 1 ) {
                $formattedCount = $this->msg( 'ntimes' )->numParams( $count )->escaped();
                $text .= ' ' . $this->msg( 'parentheses' )->rawParams( $formattedCount )->escaped();
            }
            array_push( $users, $text );
        }
 
        # Article link
        $articleLink = '';
        $revDeletedMsg = false;
        if ( $namehidden ) {
            $revDeletedMsg = $this->msg( 'rev-deleted-event' )->escaped();
        } elseif ( $allLogs ) {
            $articleLink = $this->maybeWatchedLink( $block[0]->link, $block[0]->watched );
        } else {
            $articleLink = $this->getArticleLink( $block[0], $block[0]->unpatrolled, $block[0]->watched );
        }
 
        $queryParams['curid'] = $curId;
 
        # Sub-entries
        $lines = [];
        foreach ( $block as $i => $rcObj ) {
            $line = $this->getLineData( $block, $rcObj, $queryParams );
            if ( !$line ) {
                // completely ignore this RC entry if we don't want to render it
                unset( $block[$i] );
                continue;
            }
 
            // Roll up flags
            foreach ( $line['recentChangesFlagsRaw'] as $key => $value ) {
                $flagGrouping = ( isset( $recentChangesFlags[$key]['grouping'] ) ?
                    $recentChangesFlags[$key]['grouping'] : 'any' );
                switch ( $flagGrouping ) {
                    case 'all':
                        if ( !$value ) {
                            $collectedRcFlags[$key] = false;
                        }
                        break;
                    case 'any':
                        if ( $value ) {
                            $collectedRcFlags[$key] = true;
                        }
                        break;
                    default:
                        throw new DomainException( "Unknown grouping type \"{$flagGrouping}\"" );
                }
            }
 
            $lines[] = $line;
        }
 
        // Further down are some assumptions that $block is a 0-indexed array
        // with (count-1) as last key. Let's make sure it is.
        $block = array_values( $block );
 
        if ( empty( $block ) || !$lines ) {
            // if we can't show anything, don't display this block altogether
            return '';
        }
 
        $logText = $this->getLogText( $block, $queryParams, $allLogs,
            $collectedRcFlags['newpage'], $namehidden
        );
 
        # Character difference (does not apply if only log items)
        $charDifference = false;
        if ( $RCShowChangedSize && !$allLogs ) {
            $last = 0;
            $first = count( $block ) - 1;
            # Some events (like logs and category changes) have an "empty" size, so we need to skip those...
            while ( $last < $first && $block[$last]->mAttribs['rc_new_len'] === null ) {
                $last++;
            }
            while ( $last < $first && $block[$first]->mAttribs['rc_old_len'] === null ) {
                $first--;
            }
            # Get net change
            $charDifference = $this->formatCharacterDifference( $block[$first], $block[$last] );
        }
 
        $numberofWatchingusers = $this->numberofWatchingusers( $block[0]->numberofWatchingusers );
        $usersList = $this->msg( 'brackets' )->rawParams(
            implode( $this->message['semicolon-separator'], $users )
        )->escaped();
 
        $prefix = '';
        if ( is_callable( $this->changeLinePrefixer ) ) {
            $prefix = call_user_func( $this->changeLinePrefixer, $block[0], $this, true );
        }
 
        $templateParams = [
            'articleLink' => $articleLink,
            'charDifference' => $charDifference,
            'collectedRcFlags' => $this->recentChangesFlags( $collectedRcFlags ),
            'languageDirMark' => $this->getLanguage()->getDirMark(),
            'lines' => $lines,
            'logText' => $logText,
            'numberofWatchingusers' => $numberofWatchingusers,
            'prefix' => $prefix,
            'rev-deleted-event' => $revDeletedMsg,
            'tableClasses' => $tableClasses,
            'timestamp' => $block[0]->timestamp,
            'fullTimestamp' => $block[0]->getAttribute( 'rc_timestamp' ),
            'users' => $usersList,
        ];
 
        $this->rcCacheIndex++;
 
        return $this->templateParser->processTemplate(
            'EnhancedChangesListGroup',
            $templateParams
        );
    }
 
    protected function getLineData( array $block, RCCacheEntry $rcObj, array $queryParams = [] ) {
        $RCShowChangedSize = $this->getConfig()->get( 'RCShowChangedSize' );
 
        $type = $rcObj->mAttribs['rc_type'];
        $data = [];
        $lineParams = [ 'targetTitle' => $rcObj->getTitle() ];
 
        $classes = [ 'mw-enhanced-rc' ];
        if ( $rcObj->watched
            && $rcObj->mAttribs['rc_timestamp'] >= $rcObj->watched
        ) {
            $classes[] = 'mw-enhanced-watched';
        }
        $classes = array_merge( $classes, $this->getHTMLClasses( $rcObj, $rcObj->watched ) );
 
        $separator = ' <span class="mw-changeslist-separator">. .</span> ';
 
        $data['recentChangesFlags'] = [
            'newpage' => $type == RC_NEW,
            'minor' => $rcObj->mAttribs['rc_minor'],
            'unpatrolled' => $rcObj->unpatrolled,
            'bot' => $rcObj->mAttribs['rc_bot'],
        ];
 
        $params = $queryParams;
 
        if ( $rcObj->mAttribs['rc_this_oldid'] != 0 ) {
            $params['oldid'] = $rcObj->mAttribs['rc_this_oldid'];
        }
 
        # Log timestamp
        if ( $type == RC_LOG ) {
            $link = $rcObj->timestamp;
            # Revision link
        } elseif ( !ChangesList::userCan( $rcObj, Revision::DELETED_TEXT, $this->getUser() ) ) {
            $link = '<span class="history-deleted">' . $rcObj->timestamp . '</span> ';
        } else {
            $link = $this->linkRenderer->makeKnownLink(
                $rcObj->getTitle(),
                new HtmlArmor( $rcObj->timestamp ),
                [],
                $params
            );
            if ( $this->isDeleted( $rcObj, Revision::DELETED_TEXT ) ) {
                $link = '<span class="history-deleted">' . $link . '</span> ';
            }
        }
        $data['timestampLink'] = $link;
 
        $currentAndLastLinks = '';
        if ( !$type == RC_LOG || $type == RC_NEW ) {
            $currentAndLastLinks .= ' ' . $this->msg( 'parentheses' )->rawParams(
                    $rcObj->curlink .
                    $this->message['pipe-separator'] .
                    $rcObj->lastlink
                )->escaped();
        }
        $data['currentAndLastLinks'] = $currentAndLastLinks;
        $data['separatorAfterCurrentAndLastLinks'] = $separator;
 
        # Character diff
        if ( $RCShowChangedSize ) {
            $cd = $this->formatCharacterDifference( $rcObj );
            if ( $cd !== '' ) {
                $data['characterDiff'] = $cd;
                $data['separatorAfterCharacterDiff'] = $separator;
            }
        }
 
        if ( $rcObj->mAttribs['rc_type'] == RC_LOG ) {
            $data['logEntry'] = $this->insertLogEntry( $rcObj );
        } elseif ( $this->isCategorizationWithoutRevision( $rcObj ) ) {
            $data['comment'] = $this->insertComment( $rcObj );
        } else {
            # User links
            $data['userLink'] = $rcObj->userlink;
            $data['userTalkLink'] = $rcObj->usertalklink;
            $data['comment'] = $this->insertComment( $rcObj );
        }
 
        # Rollback
        $data['rollback'] = $this->getRollback( $rcObj );
 
        # Tags
        $data['tags'] = $this->getTags( $rcObj, $classes );
 
        $attribs = $this->getDataAttributes( $rcObj );
 
        // give the hook a chance to modify the data
        $success = Hooks::run( 'EnhancedChangesListModifyLineData',
            [ $this, &$data, $block, $rcObj, &$classes, &$attribs ] );
        if ( !$success ) {
            // skip entry if hook aborted it
            return [];
        }
        $attribs = wfArrayFilterByKey( $attribs, [ Sanitizer::class, 'isReservedDataAttribute' ] );
 
        $lineParams['recentChangesFlagsRaw'] = [];
        if ( isset( $data['recentChangesFlags'] ) ) {
            $lineParams['recentChangesFlags'] = $this->recentChangesFlags( $data['recentChangesFlags'] );
            # FIXME: This is used by logic, don't return it in the template params.
            $lineParams['recentChangesFlagsRaw'] = $data['recentChangesFlags'];
            unset( $data['recentChangesFlags'] );
        }
 
        if ( isset( $data['timestampLink'] ) ) {
            $lineParams['timestampLink'] = $data['timestampLink'];
            unset( $data['timestampLink'] );
        }
 
        $lineParams['classes'] = array_values( $classes );
        $lineParams['attribs'] = Html::expandAttributes( $attribs );
 
        // everything else: makes it easier for extensions to add or remove data
        $lineParams['data'] = array_values( $data );
 
        return $lineParams;
    }
 
    protected function getLogText( $block, $queryParams, $allLogs, $isnew, $namehidden ) {
        if ( empty( $block ) ) {
            return '';
        }
 
        # Changes message
        static $nchanges = [];
        static $sinceLastVisitMsg = [];
 
        $n = count( $block );
        if ( !isset( $nchanges[$n] ) ) {
            $nchanges[$n] = $this->msg( 'nchanges' )->numParams( $n )->escaped();
        }
 
        $sinceLast = 0;
        $unvisitedOldid = null;
        foreach ( $block as $rcObj ) {
            // Same logic as below inside main foreach
            if ( $rcObj->watched && $rcObj->mAttribs['rc_timestamp'] >= $rcObj->watched ) {
                $sinceLast++;
                $unvisitedOldid = $rcObj->mAttribs['rc_last_oldid'];
            }
        }
        if ( !isset( $sinceLastVisitMsg[$sinceLast] ) ) {
            $sinceLastVisitMsg[$sinceLast] =
                $this->msg( 'enhancedrc-since-last-visit' )->numParams( $sinceLast )->escaped();
        }
 
        $currentRevision = 0;
        foreach ( $block as $rcObj ) {
            if ( !$currentRevision ) {
                $currentRevision = $rcObj->mAttribs['rc_this_oldid'];
            }
        }
 
        # Total change link
        $links = [];
        $block0 = $block[0];
        $last = $block[count( $block ) - 1];
        if ( !$allLogs ) {
            if ( !ChangesList::userCan( $rcObj, Revision::DELETED_TEXT, $this->getUser() ) ||
                $isnew ||
                $rcObj->mAttribs['rc_type'] == RC_CATEGORIZE
            ) {
                $links['total-changes'] = $nchanges[$n];
            } else {
                $links['total-changes'] = $this->linkRenderer->makeKnownLink(
                    $block0->getTitle(),
                    new HtmlArmor( $nchanges[$n] ),
                    [ 'class' => 'mw-changeslist-groupdiff' ],
                    $queryParams + [
                        'diff' => $currentRevision,
                        'oldid' => $last->mAttribs['rc_last_oldid'],
                    ]
                );
                if ( $sinceLast > 0 && $sinceLast < $n ) {
                    $links['total-changes-since-last'] = $this->linkRenderer->makeKnownLink(
                            $block0->getTitle(),
                            new HtmlArmor( $sinceLastVisitMsg[$sinceLast] ),
                            [ 'class' => 'mw-changeslist-groupdiff' ],
                            $queryParams + [
                                'diff' => $currentRevision,
                                'oldid' => $unvisitedOldid,
                            ]
                        );
                }
            }
        }
 
        # History
        if ( $allLogs || $rcObj->mAttribs['rc_type'] == RC_CATEGORIZE ) {
            // don't show history link for logs
        } elseif ( $namehidden || !$block0->getTitle()->exists() ) {
            $links['history'] = $this->message['enhancedrc-history'];
        } else {
            $params = $queryParams;
            $params['action'] = 'history';
 
            $links['history'] = $this->linkRenderer->makeKnownLink(
                    $block0->getTitle(),
                    new HtmlArmor( $this->message['enhancedrc-history'] ),
                    [ 'class' => 'mw-changeslist-history' ],
                    $params
                );
        }
 
        # Allow others to alter, remove or add to these links
        Hooks::run( 'EnhancedChangesList::getLogText',
            [ $this, &$links, $block ] );
 
        if ( !$links ) {
            return '';
        }
 
        $logtext = implode( $this->message['pipe-separator'], $links );
        $logtext = $this->msg( 'parentheses' )->rawParams( $logtext )->escaped();
        return ' ' . $logtext;
    }
 
    protected function recentChangesBlockLine( $rcObj ) {
        $data = [];
 
        $query['curid'] = $rcObj->mAttribs['rc_cur_id'];
 
        $type = $rcObj->mAttribs['rc_type'];
        $logType = $rcObj->mAttribs['rc_log_type'];
        $classes = $this->getHTMLClasses( $rcObj, $rcObj->watched );
        $classes[] = 'mw-enhanced-rc';
 
        if ( $logType ) {
            # Log entry
            $classes[] = 'mw-changeslist-log';
            $classes[] = Sanitizer::escapeClass( 'mw-changeslist-log-' . $logType );
        } else {
            $classes[] = 'mw-changeslist-edit';
            $classes[] = Sanitizer::escapeClass( 'mw-changeslist-ns' .
                $rcObj->mAttribs['rc_namespace'] . '-' . $rcObj->mAttribs['rc_title'] );
        }
 
        # Flag and Timestamp
        $data['recentChangesFlags'] = [
            'newpage' => $type == RC_NEW,
            'minor' => $rcObj->mAttribs['rc_minor'],
            'unpatrolled' => $rcObj->unpatrolled,
            'bot' => $rcObj->mAttribs['rc_bot'],
        ];
        // timestamp is not really a link here, but is called timestampLink
        // for consistency with EnhancedChangesListModifyLineData
        $data['timestampLink'] = $rcObj->timestamp;
 
        # Article or log link
        if ( $logType ) {
            $logPage = new LogPage( $logType );
            $logTitle = SpecialPage::getTitleFor( 'Log', $logType );
            $logName = $logPage->getName()->text();
            $data['logLink'] = $this->msg( 'parentheses' )
                ->rawParams(
                    $this->linkRenderer->makeKnownLink( $logTitle, $logName )
                )->escaped();
        } else {
            $data['articleLink'] = $this->getArticleLink( $rcObj, $rcObj->unpatrolled, $rcObj->watched );
        }
 
        # Diff and hist links
        if ( $type != RC_LOG && $type != RC_CATEGORIZE ) {
            $query['action'] = 'history';
            $data['historyLink'] = $this->getDiffHistLinks( $rcObj, $query );
        }
        $data['separatorAfterLinks'] = ' <span class="mw-changeslist-separator">. .</span> ';
 
        # Character diff
        if ( $this->getConfig()->get( 'RCShowChangedSize' ) ) {
            $cd = $this->formatCharacterDifference( $rcObj );
            if ( $cd !== '' ) {
                $data['characterDiff'] = $cd;
                $data['separatorAftercharacterDiff'] = ' <span class="mw-changeslist-separator">. .</span> ';
            }
        }
 
        if ( $type == RC_LOG ) {
            $data['logEntry'] = $this->insertLogEntry( $rcObj );
        } elseif ( $this->isCategorizationWithoutRevision( $rcObj ) ) {
            $data['comment'] = $this->insertComment( $rcObj );
        } else {
            $data['userLink'] = $rcObj->userlink;
            $data['userTalkLink'] = $rcObj->usertalklink;
            $data['comment'] = $this->insertComment( $rcObj );
            if ( $type == RC_CATEGORIZE ) {
                $data['historyLink'] = $this->getDiffHistLinks( $rcObj, $query );
            }
            $data['rollback'] = $this->getRollback( $rcObj );
        }
 
        # Tags
        $data['tags'] = $this->getTags( $rcObj, $classes );
 
        # Show how many people are watching this if enabled
        $data['watchingUsers'] = $this->numberofWatchingusers( $rcObj->numberofWatchingusers );
 
        $data['attribs'] = array_merge( $this->getDataAttributes( $rcObj ), [ 'class' => $classes ] );
 
        // give the hook a chance to modify the data
        $success = Hooks::run( 'EnhancedChangesListModifyBlockLineData',
            [ $this, &$data, $rcObj ] );
        if ( !$success ) {
            // skip entry if hook aborted it
            return '';
        }
        $attribs = $data['attribs'];
        unset( $data['attribs'] );
        $attribs = wfArrayFilterByKey( $attribs, function ( $key ) {
            return $key === 'class' || Sanitizer::isReservedDataAttribute( $key );
        } );
 
        $prefix = '';
        if ( is_callable( $this->changeLinePrefixer ) ) {
            $prefix = call_user_func( $this->changeLinePrefixer, $rcObj, $this, false );
        }
 
        $line = Html::openElement( 'table', $attribs ) . Html::openElement( 'tr' );
        $line .= Html::rawElement( 'td', [], '<span class="mw-enhancedchanges-arrow-space"></span>' );
        $line .= Html::rawElement( 'td', [ 'class' => 'mw-changeslist-line-prefix' ], $prefix );
        $line .= '<td class="mw-enhanced-rc">';
 
        if ( isset( $data['recentChangesFlags'] ) ) {
            $line .= $this->recentChangesFlags( $data['recentChangesFlags'] );
            unset( $data['recentChangesFlags'] );
        }
 
        if ( isset( $data['timestampLink'] ) ) {
            $line .= '&#160;' . $data['timestampLink'];
            unset( $data['timestampLink'] );
        }
        $line .= '&#160;</td>';
        $line .= Html::openElement( 'td', [
            'class' => 'mw-changeslist-line-inner',
            // Used for reliable determination of the affiliated page
            'data-target-page' => $rcObj->getTitle(),
        ] );
 
        // everything else: makes it easier for extensions to add or remove data
        $line .= implode( '', $data );
 
        $line .= "</td></tr></table>\n";
 
        return $line;
    }
 
    public function getDiffHistLinks( RCCacheEntry $rc, array $query ) {
        $pageTitle = $rc->getTitle();
        if ( $rc->getAttribute( 'rc_type' ) == RC_CATEGORIZE ) {
            // For categorizations we must swap the category title with the page title!
            $pageTitle = Title::newFromID( $rc->getAttribute( 'rc_cur_id' ) );
            if ( !$pageTitle ) {
                // The page has been deleted, but the RC entry
                // deletion job has not run yet. Just skip.
                return '';
            }
        }
 
        $retVal = ' ' . $this->msg( 'parentheses' )
                ->rawParams( $rc->difflink . $this->message['pipe-separator']
                    . $this->linkRenderer->makeKnownLink(
                        $pageTitle,
                        new HtmlArmor( $this->message['hist'] ),
                        [ 'class' => 'mw-changeslist-history' ],
                        $query
                    ) )->escaped();
        return $retVal;
    }
 
    protected function recentChangesBlock() {
        if ( count( $this->rc_cache ) == 0 ) {
            return '';
        }
 
        $blockOut = '';
        foreach ( $this->rc_cache as $block ) {
            if ( count( $block ) < 2 ) {
                $blockOut .= $this->recentChangesBlockLine( array_shift( $block ) );
            } else {
                $blockOut .= $this->recentChangesBlockGroup( $block );
            }
        }
 
        if ( $blockOut === '' ) {
            return '';
        }
        // $this->lastdate is kept up to date by recentChangesLine()
        return Xml::element( 'h4', null, $this->lastdate ) . "\n<div>" . $blockOut . '</div>';
    }
 
    public function endRecentChangesList() {
        return $this->recentChangesBlock() . '</div>';
    }
}