includes/PageHistory.php

   1 <?php
   2 /**
   3  * Page history
   4  *
   5  * Split off from Article.php and Skin.php, 2003-12-22
   6  */
   7
   8 /**
   9  * This class handles printing the history page for an article.  In order to
  10  * be efficient, it uses timestamps rather than offsets for paging, to avoid
  11  * costly LIMIT,offset queries.
  12  *
  13  * Construct it by passing in an Article, and call $h->history() to print the
  14  * history.
  15  *
  16  */
  17 class PageHistory {
  18         const DIR_PREV = 0;
  19         const DIR_NEXT = 1;
  20
  21         var $mArticle, $mTitle, $mSkin;
  22         var $lastdate;
  23         var $linesonpage;
  24         var $mNotificationTimestamp;
  25         var $mLatestId = null;
  26
  27         /**
  28          * Construct a new PageHistory.
  29          *
  30          * @param Article $article
  31          * @returns nothing
  32          */
  33         function __construct($article) {
  34                 global $wgUser;
  35
  36                 $this->mArticle =& $article;
  37                 $this->mTitle =& $article->mTitle;
  38                 $this->mNotificationTimestamp = NULL;
  39                 $this->mSkin = $wgUser->getSkin();
  40                 $this->preCacheMessages();
  41         }
  42
  43         /**
  44          * As we use the same small set of messages in various methods and that
  45          * they are called often, we call them once and save them in $this->message
  46          */
  47         function preCacheMessages() {
  48                 // Precache various messages
  49                 if( !isset( $this->message ) ) {
  50                         foreach( explode(' ', 'cur last rev-delundel' ) as $msg ) {
  51                                 $this->message[$msg] = wfMsgExt( $msg, array( 'escape') );
  52                         }
  53                 }
  54         }
  55
  56         /**
  57          * Print the history page for an article.
  58          *
  59          * @returns nothing
  60          */
  61         function history() {
  62                 global $wgOut, $wgRequest, $wgTitle;
  63
  64                 /*
  65                  * Allow client caching.
  66                  */
  67
  68                 if( $wgOut->checkLastModified( $this->mArticle->getTouched() ) )
  69                         /* Client cache fresh and headers sent, nothing more to do. */
  70                         return;
  71
  72                 wfProfileIn( __METHOD__ );
  73
  74                 /*
  75                  * Setup page variables.
  76                  */
  77                 $wgOut->setPageTitle( wfMsg( 'history-title', $this->mTitle->getPrefixedText() ) );
  78                 $wgOut->setPageTitleActionText( wfMsg( 'history_short' ) );
  79                 $wgOut->setArticleFlag( false );
  80                 $wgOut->setArticleRelated( true );
  81                 $wgOut->setRobotpolicy( 'noindex,nofollow' );
  82                 $wgOut->setSyndicated( true );
  83                 $wgOut->setFeedAppendQuery( 'action=history' );
  84                 $wgOut->addScriptFile( 'history.js' );
  85
  86                 $logPage = SpecialPage::getTitleFor( 'Log' );
  87                 $logLink = $this->mSkin->makeKnownLinkObj( $logPage, wfMsgHtml( 'viewpagelogs' ), 'page=' . $this->mTitle->getPrefixedUrl() );
  88                 $wgOut->setSubtitle( $logLink );
  89
  90                 $feedType = $wgRequest->getVal( 'feed' );
  91                 if( $feedType ) {
  92                         wfProfileOut( __METHOD__ );
  93                         return $this->feed( $feedType );
  94                 }
  95
  96                 /*
  97                  * Fail if article doesn't exist.
  98                  */
  99                 if( !$this->mTitle->exists() ) {
 100                         $wgOut->addWikiMsg( 'nohistory' );
 101                         wfProfileOut( __METHOD__ );
 102                         return;
 103                 }
 104
 105                 /*
 106                  * "go=first" means to jump to the last (earliest) history page.
 107                  * This is deprecated, it no longer appears in the user interface
 108                  */
 109                 if ( $wgRequest->getText("go") == 'first' ) {
 110                         $limit = $wgRequest->getInt( 'limit', 50 );
 111                         global $wgFeedLimit;
 112                         if( $limit > $wgFeedLimit ) {
 113                                 $limit = $wgFeedLimit;
 114                         }
 115                         $wgOut->redirect( $wgTitle->getLocalURL( "action=history&limit={$limit}&dir=prev" ) );
 116                         return;
 117                 }
 118
 119                 wfRunHooks( 'PageHistoryBeforeList', array( &$this->mArticle ) );
 120
 121                 /**
 122                  * Do the list
 123                  */
 124                 $pager = new PageHistoryPager( $this );
 125                 $this->linesonpage = $pager->getNumRows();
 126                 $wgOut->addHTML(
 127                         $pager->getNavigationBar() .
 128                         $this->beginHistoryList() .
 129                         $pager->getBody() .
 130                         $this->endHistoryList() .
 131                         $pager->getNavigationBar()
 132                 );
 133                 wfProfileOut( __METHOD__ );
 134         }
 135
 136         /**
 137          * Creates begin of history list with a submit button
 138          *
 139          * @return string HTML output
 140          */
 141         function beginHistoryList() {
 142                 global $wgTitle, $wgScript;
 143                 $this->lastdate = '';
 144                 $s = wfMsgExt( 'histlegend', array( 'parse') );
 145                 $s .= Xml::openElement( 'form', array( 'action' => $wgScript ) );
 146                 $s .= Xml::hidden( 'title', $wgTitle->getPrefixedDbKey() );
 147                 $s .= $this->submitButton();
 148                 $s .= '<ul id="pagehistory">' . "\n";
 149                 return $s;
 150         }
 151
 152         /**
 153          * Creates end of history list with a submit button
 154          *
 155          * @return string HTML output
 156          */
 157         function endHistoryList() {
 158                 $s = '</ul>';
 159                 $s .= $this->submitButton( array( 'id' => 'historysubmit' ) );
 160                 $s .= '</form>';
 161                 return $s;
 162         }
 163
 164         /**
 165          * Creates a submit button
 166          *
 167          * @param array $bits optional CSS ID
 168          * @return string HTML output for the submit button
 169          */
 170         function submitButton( $bits = array() ) {
 171                 # Disable submit button if history has 1 revision only
 172                 if ( $this->linesonpage > 1 ) {
 173                         return Xml::submitButton( wfMsg( 'compareselectedversions' ),
 174                                 $bits + array(
 175                                         'class'     => 'historysubmit',
 176                                         'accesskey' => wfMsg( 'accesskey-compareselectedversions' ),
 177                                         'title'     => wfMsg( 'tooltip-compareselectedversions' ),
 178                                         )
 179                                 );
 180                 } else {
 181                         return '';
 182                 }
 183         }
 184
 185         /**
 186          * Returns a row from the history printout.
 187          *
 188          * @todo document some more, and maybe clean up the code (some params redundant?)
 189          *
 190          * @param Row $row The database row corresponding to the previous line.
 191          * @param mixed $next The database row corresponding to the next line.
 192          * @param int $counter Apparently a counter of what row number we're at, counted from the top row = 1.
 193          * @param $notificationtimestamp
 194          * @param bool $latest Whether this row corresponds to the page's latest revision.
 195          * @param bool $firstInList Whether this row corresponds to the first displayed on this history page.
 196          * @return string HTML output for the row
 197          */
 198         function historyLine( $row, $next, $counter = '', $notificationtimestamp = false, $latest = false, $firstInList = false ) {
 199                 global $wgUser, $wgLang;
 200                 $rev = new Revision( $row );
 201                 $rev->setTitle( $this->mTitle );
 202
 203                 $s = '';
 204                 $curlink = $this->curLink( $rev, $latest );
 205                 $lastlink = $this->lastLink( $rev, $next, $counter );
 206                 $arbitrary = $this->diffButtons( $rev, $firstInList, $counter );
 207                 $link = $this->revLink( $rev );
 208
 209                 $s .= "($curlink) ($lastlink) $arbitrary";
 210
 211                 if( $wgUser->isAllowed( 'deleterevision' ) ) {
 212                         $revdel = SpecialPage::getTitleFor( 'Revisiondelete' );
 213                         if( $firstInList ) {
 214                         // We don't currently handle well changing the top revision's settings
 215                                 $del = $this->message['rev-delundel'];
 216                         } else if( !$rev->userCan( Revision::DELETED_RESTRICTED ) ) {
 217                         // If revision was hidden from sysops
 218                                 $del = $this->message['rev-delundel'];
 219                         } else {
 220                                 $del = $this->mSkin->makeKnownLinkObj( $revdel,
 221                                         $this->message['rev-delundel'],
 222                                         'target=' . urlencode( $this->mTitle->getPrefixedDbkey() ) .
 223                                         '&oldid=' . urlencode( $rev->getId() ) );
 224                                 // Bolden oversighted content
 225                                 if( $rev->isDeleted( Revision::DELETED_RESTRICTED ) )
 226                                         $del = "<strong>$del</strong>";
 227                         }
 228                         $s .= " <tt>(<small>$del</small>)</tt> ";
 229                 }
 230
 231                 $s .= " $link";
 232                 $s .= " <span class='history-user'>" . $this->mSkin->revUserTools( $rev, true ) . "</span>";
 233
 234                 if( $row->rev_minor_edit ) {
 235                         $s .= ' ' . Xml::element( 'span', array( 'class' => 'minor' ), wfMsg( 'minoreditletter') );
 236                 }
 237
 238                 if ( !is_null( $size = $rev->getSize() ) && $rev->userCan( Revision::DELETED_TEXT ) ) {
 239                         if ( $size == 0 )
 240                                 $stxt = wfMsgHtml( 'historyempty' );
 241                         else
 242                                 $stxt = wfMsgExt( 'historysize', array( 'parsemag' ), $wgLang->formatNum( $size ) );
 243                         $s .= " <span class=\"history-size\">$stxt</span>";
 244                 }
 245
 246                 $s .= $this->mSkin->revComment( $rev, false, true );
 247
 248                 if ($notificationtimestamp && ($row->rev_timestamp >= $notificationtimestamp)) {
 249                         $s .= ' <span class="updatedmarker">' .  wfMsgHtml( 'updatedmarker' ) . '</span>';
 250                 }
 251                 #add blurb about text having been deleted
 252                 if( $rev->isDeleted( Revision::DELETED_TEXT ) ) {
 253                         $s .= ' <tt>' . wfMsgHtml( 'deletedrev' ) . '</tt>';
 254                 }
 255
 256                 $tools = array();
 257
 258                 if ( !is_null( $next ) && is_object( $next ) ) {
 259                         if( !$this->mTitle->getUserPermissionsErrors( 'rollback', $wgUser )
 260                         && !$this->mTitle->getUserPermissionsErrors( 'edit', $wgUser )
 261                         && $latest ) {
 262                                 $tools[] = '<span class="mw-rollback-link">'
 263                                         . $this->mSkin->buildRollbackLink( $rev )
 264                                         . '</span>';
 265                         }
 266
 267                         if( $this->mTitle->quickUserCan( 'edit' ) &&
 268                                 !$rev->isDeleted( Revision::DELETED_TEXT ) &&
 269                                 !$next->rev_deleted & Revision::DELETED_TEXT ) {
 270                                 $undolink = $this->mSkin->makeKnownLinkObj(
 271                                         $this->mTitle,
 272                                         wfMsgHtml( 'editundo' ),
 273                                         'action=edit&undoafter=' . $next->rev_id . '&undo=' . $rev->getId()
 274                                 );
 275                                 $tools[] = "<span class=\"mw-history-undo\">{$undolink}</span>";
 276                         }
 277                 }
 278
 279                 if( $tools ) {
 280                         $s .= ' (' . implode( ' | ', $tools ) . ')';
 281                 }
 282
 283                 wfRunHooks( 'PageHistoryLineEnding', array( &$row , &$s ) );
 284
 285                 return "<li>$s</li>\n";
 286         }
 287
 288         /**
 289         * Create a link to view this revision of the page
 290         * @param Revision $rev
 291         * @returns string
 292         */
 293         function revLink( $rev ) {
 294                 global $wgLang;
 295                 $date = $wgLang->timeanddate( wfTimestamp(TS_MW, $rev->getTimestamp()), true );
 296                 if( $rev->userCan( Revision::DELETED_TEXT ) ) {
 297                         $link = $this->mSkin->makeKnownLinkObj(
 298                                 $this->mTitle, $date, "oldid=" . $rev->getId() );
 299                 } else {
 300                         $link = $date;
 301                 }
 302                 if( $rev->isDeleted( Revision::DELETED_TEXT ) ) {
 303                         return '<span class="history-deleted">' . $link . '</span>';
 304                 }
 305                 return $link;
 306         }
 307
 308         /**
 309         * Create a diff-to-current link for this revision for this page
 310         * @param Revision $rev
 311         * @param Bool $latest, this is the latest revision of the page?
 312         * @returns string
 313         */
 314         function curLink( $rev, $latest ) {
 315                 $cur = $this->message['cur'];
 316                 if( $latest || !$rev->userCan( Revision::DELETED_TEXT ) ) {
 317                         return $cur;
 318                 } else {
 319                         return $this->mSkin->makeKnownLinkObj(
 320                                 $this->mTitle, $cur,
 321                                 'diff=' . $this->getLatestID() .
 322                                 "&oldid=" . $rev->getId() );
 323                 }
 324         }
 325
 326         /**
 327         * Create a diff-to-previous link for this revision for this page.
 328         * @param Revision $prevRev, the previous revision
 329         * @param mixed $next, the newer revision
 330         * @param int $counter, what row on the history list this is
 331         * @returns string
 332         */
 333         function lastLink( $prevRev, $next, $counter ) {
 334                 $last = $this->message['last'];
 335                 # $next may either be a Row, null, or "unkown"
 336                 $nextRev = is_object($next) ? new Revision( $next ) : $next;
 337                 if( is_null($next) ) {
 338                         # Probably no next row
 339                         return $last;
 340                 } elseif( $next === 'unknown' ) {
 341                         # Next row probably exists but is unknown, use an oldid=prev link
 342                         return $this->mSkin->makeKnownLinkObj(
 343                                 $this->mTitle,
 344                                 $last,
 345                                 "diff=" . $prevRev->getId() . "&oldid=prev" );
 346                 } elseif( !$prevRev->userCan(Revision::DELETED_TEXT) || !$nextRev->userCan(Revision::DELETED_TEXT) ) {
 347                         return $last;
 348                 } else {
 349                         return $this->mSkin->makeKnownLinkObj(
 350                                 $this->mTitle,
 351                                 $last,
 352                                 "diff=" . $prevRev->getId() . "&oldid={$next->rev_id}"
 353                                 /*,
 354                                 '',
 355                                 '',
 356                                 "tabindex={$counter}"*/ );
 357                 }
 358         }
 359
 360         /**
 361          * Create radio buttons for page history
 362          *
 363          * @param object $rev Revision
 364          * @param bool $firstInList Is this version the first one?
 365          * @param int $counter A counter of what row number we're at, counted from the top row = 1.
 366          * @return string HTML output for the radio buttons
 367          */
 368         function diffButtons( $rev, $firstInList, $counter ) {
 369                 if( $this->linesonpage > 1) {
 370                         $radio = array(
 371                                 'type'  => 'radio',
 372                                 'value' => $rev->getId(),
 373                         );
 374
 375                         if( !$rev->userCan( Revision::DELETED_TEXT ) ) {
 376                                 $radio['disabled'] = 'disabled';
 377                         }
 378
 379                         /** @todo: move title texts to javascript */
 380                         if ( $firstInList ) {
 381                                 $first = Xml::element( 'input', array_merge(
 382                                         $radio,
 383                                         array(
 384                                                 'style' => 'visibility:hidden',
 385                                                 'name'  => 'oldid' ) ) );
 386                                 $checkmark = array( 'checked' => 'checked' );
 387                         } else {
 388                                 if( $counter == 2 ) {
 389                                         $checkmark = array( 'checked' => 'checked' );
 390                                 } else {
 391                                         $checkmark = array();
 392                                 }
 393                                 $first = Xml::element( 'input', array_merge(
 394                                         $radio,
 395                                         $checkmark,
 396                                         array( 'name'  => 'oldid' ) ) );
 397                                 $checkmark = array();
 398                         }
 399                         $second = Xml::element( 'input', array_merge(
 400                                 $radio,
 401                                 $checkmark,
 402                                 array( 'name'  => 'diff' ) ) );
 403                         return $first . $second;
 404                 } else {
 405                         return '';
 406                 }
 407         }
 408
 409         /** @todo document */
 410         function getLatestId() {
 411                 if( is_null( $this->mLatestId ) ) {
 412                         $id = $this->mTitle->getArticleID();
 413                         $db = wfGetDB( DB_SLAVE );
 414                         $this->mLatestId = $db->selectField( 'page',
 415                                 "page_latest",
 416                                 array( 'page_id' => $id ),
 417                                 __METHOD__ );
 418                 }
 419                 return $this->mLatestId;
 420         }
 421
 422         /**
 423          * Fetch an array of revisions, specified by a given limit, offset and
 424          * direction. This is now only used by the feeds. It was previously
 425          * used by the main UI but that's now handled by the pager.
 426          */
 427         function fetchRevisions($limit, $offset, $direction) {
 428                 $dbr = wfGetDB( DB_SLAVE );
 429
 430                 if ($direction == PageHistory::DIR_PREV)
 431                         list($dirs, $oper) = array("ASC", ">=");
 432                 else /* $direction == PageHistory::DIR_NEXT */
 433                         list($dirs, $oper) = array("DESC", "<=");
 434
 435                 if ($offset)
 436                         $offsets = array("rev_timestamp $oper '$offset'");
 437                 else
 438                         $offsets = array();
 439
 440                 $page_id = $this->mTitle->getArticleID();
 441
 442                 $res = $dbr->select(
 443                         'revision',
 444                         Revision::selectFields(),
 445                         array_merge(array("rev_page=$page_id"), $offsets),
 446                         __METHOD__,
 447                         array('ORDER BY' => "rev_timestamp $dirs",
 448                                 'USE INDEX' => 'page_timestamp', 'LIMIT' => $limit)
 449                         );
 450
 451                 $result = array();
 452                 while (($obj = $dbr->fetchObject($res)) != NULL)
 453                         $result[] = $obj;
 454
 455                 return $result;
 456         }
 457
 458         /** @todo document */
 459         function getNotificationTimestamp() {
 460                 global $wgUser, $wgShowUpdatedMarker;
 461
 462                 if ($this->mNotificationTimestamp !== NULL)
 463                         return $this->mNotificationTimestamp;
 464
 465                 if ($wgUser->isAnon() || !$wgShowUpdatedMarker)
 466                         return $this->mNotificationTimestamp = false;
 467
 468                 $dbr = wfGetDB(DB_SLAVE);
 469
 470                 $this->mNotificationTimestamp = $dbr->selectField(
 471                         'watchlist',
 472                         'wl_notificationtimestamp',
 473                         array(  'wl_namespace' => $this->mTitle->getNamespace(),
 474                                 'wl_title' => $this->mTitle->getDBkey(),
 475                                 'wl_user' => $wgUser->getID()
 476                         ),
 477                         __METHOD__ );
 478
 479                 // Don't use the special value reserved for telling whether the field is filled
 480                 if ( is_null( $this->mNotificationTimestamp ) ) {
 481                         $this->mNotificationTimestamp = false;
 482                 }
 483
 484                 return $this->mNotificationTimestamp;
 485         }
 486
 487         /**
 488          * Output a subscription feed listing recent edits to this page.
 489          * @param string $type
 490          */
 491         function feed( $type ) {
 492                 require_once 'SpecialRecentchanges.php';
 493
 494                 global $wgFeed, $wgFeedClasses;
 495
 496                 if ( !$wgFeed ) {
 497                         global $wgOut;
 498                         $wgOut->addWikiMsg( 'feed-unavailable' );
 499                         return;
 500                 }
 501
 502                 if( !isset( $wgFeedClasses[$type] ) ) {
 503                         global $wgOut;
 504                         $wgOut->addWikiMsg( 'feed-invalid' );
 505                         return;
 506                 }
 507
 508                 $feed = new $wgFeedClasses[$type](
 509                         $this->mTitle->getPrefixedText() . ' - ' .
 510                                 wfMsgForContent( 'history-feed-title' ),
 511                         wfMsgForContent( 'history-feed-description' ),
 512                         $this->mTitle->getFullUrl( 'action=history' ) );
 513
 514                 $items = $this->fetchRevisions(10, 0, PageHistory::DIR_NEXT);
 515                 $feed->outHeader();
 516                 if( $items ) {
 517                         foreach( $items as $row ) {
 518                                 $feed->outItem( $this->feedItem( $row ) );
 519                         }
 520                 } else {
 521                         $feed->outItem( $this->feedEmpty() );
 522                 }
 523                 $feed->outFooter();
 524         }
 525
 526         function feedEmpty() {
 527                 global $wgOut;
 528                 return new FeedItem(
 529                         wfMsgForContent( 'nohistory' ),
 530                         $wgOut->parse( wfMsgForContent( 'history-feed-empty' ) ),
 531                         $this->mTitle->getFullUrl(),
 532                         wfTimestamp( TS_MW ),
 533                         '',
 534                         $this->mTitle->getTalkPage()->getFullUrl() );
 535         }
 536
 537         /**
 538          * Generate a FeedItem object from a given revision table row
 539          * Borrows Recent Changes' feed generation functions for formatting;
 540          * includes a diff to the previous revision (if any).
 541          *
 542          * @param $row
 543          * @return FeedItem
 544          */
 545         function feedItem( $row ) {
 546                 $rev = new Revision( $row );
 547                 $rev->setTitle( $this->mTitle );
 548                 $text = rcFormatDiffRow( $this->mTitle,
 549                         $this->mTitle->getPreviousRevisionID( $rev->getId() ),
 550                         $rev->getId(),
 551                         $rev->getTimestamp(),
 552                         $rev->getComment() );
 553
 554                 if( $rev->getComment() == '' ) {
 555                         global $wgContLang;
 556                         $title = wfMsgForContent( 'history-feed-item-nocomment',
 557                                 $rev->getUserText(),
 558                                 $wgContLang->timeanddate( $rev->getTimestamp() ) );
 559                 } else {
 560                         $title = $rev->getUserText() . ": " . $this->stripComment( $rev->getComment() );
 561                 }
 562
 563                 return new FeedItem(
 564                         $title,
 565                         $text,
 566                         $this->mTitle->getFullUrl( 'diff=' . $rev->getId() . '&oldid=prev' ),
 567                         $rev->getTimestamp(),
 568                         $rev->getUserText(),
 569                         $this->mTitle->getTalkPage()->getFullUrl() );
 570         }
 571
 572         /**
 573          * Quickie hack... strip out wikilinks to more legible form from the comment.
 574          */
 575         function stripComment( $text ) {
 576                 return preg_replace( '/\[\[([^]]*\|)?([^]]+)\]\]/', '\2', $text );
 577         }
 578 }
 579
 580
 581 /**
 582  * @addtogroup Pager
 583  */
 584 class PageHistoryPager extends ReverseChronologicalPager {
 585         public $mLastRow = false, $mPageHistory;
 586
 587         function __construct( $pageHistory ) {
 588                 parent::__construct();
 589                 $this->mPageHistory = $pageHistory;
 590         }
 591
 592         function getQueryInfo() {
 593                 return array(
 594                         'tables' => 'revision',
 595                         'fields' => Revision::selectFields(),
 596                         'conds' => array('rev_page' => $this->mPageHistory->mTitle->getArticleID() ),
 597                         'options' => array( 'USE INDEX' => 'page_timestamp' )
 598                 );
 599         }
 600
 601         function getIndexField() {
 602                 return 'rev_timestamp';
 603         }
 604
 605         function formatRow( $row ) {
 606                 if ( $this->mLastRow ) {
 607                         $latest = $this->mCounter == 1 && $this->mIsFirst;
 608                         $firstInList = $this->mCounter == 1;
 609                         $s = $this->mPageHistory->historyLine( $this->mLastRow, $row, $this->mCounter++,
 610                                 $this->mPageHistory->getNotificationTimestamp(), $latest, $firstInList );
 611                 } else {
 612                         $s = '';
 613                 }
 614                 $this->mLastRow = $row;
 615                 return $s;
 616         }
 617
 618         function getStartBody() {
 619                 $this->mLastRow = false;
 620                 $this->mCounter = 1;
 621                 return '';
 622         }
 623
 624         function getEndBody() {
 625                 if ( $this->mLastRow ) {
 626                         $latest = $this->mCounter == 1 && $this->mIsFirst;
 627                         $firstInList = $this->mCounter == 1;
 628                         if ( $this->mIsBackwards ) {
 629                                 # Next row is unknown, but for UI reasons, probably exists if an offset has been specified
 630                                 if ( $this->mOffset == '' ) {
 631                                         $next = null;
 632                                 } else {
 633                                         $next = 'unknown';
 634                                 }
 635                         } else {
 636                                 # The next row is the past-the-end row
 637                                 $next = $this->mPastTheEndRow;
 638                         }
 639                         $s = $this->mPageHistory->historyLine( $this->mLastRow, $next, $this->mCounter++,
 640                                 $this->mPageHistory->getNotificationTimestamp(), $latest, $firstInList );
 641                 } else {
 642                         $s = '';
 643                 }
 644                 return $s;
 645         }
 646 }