includes/diff/DifferenceEngine.php

   1 <?php
   2 /**
   3  * User interface for the difference engine
   4  *
   5  * @file
   6  * @ingroup DifferenceEngine
   7  */
   8
   9 /**
  10  * Constant to indicate diff cache compatibility.
  11  * Bump this when changing the diff formatting in a way that
  12  * fixes important bugs or such to force cached diff views to
  13  * clear.
  14  */
  15 define( 'MW_DIFF_VERSION', '1.11a' );
  16
  17 /**
  18  * @todo document
  19  * @ingroup DifferenceEngine
  20  */
  21 class DifferenceEngine {
  22         /**#@+
  23          * @private
  24          */
  25         var $mOldid, $mNewid;
  26         var $mOldtitle, $mNewtitle, $mPagetitle;
  27         var $mOldtext, $mNewtext;
  28
  29         /**
  30          * @var Title
  31          */
  32         var $mOldPage, $mNewPage, $mTitle;
  33         var $mRcidMarkPatrolled;
  34
  35         /**
  36          * @var Revision
  37          */
  38         var $mOldRev, $mNewRev;
  39         var $mRevisionsLoaded = false; // Have the revisions been loaded
  40         var $mTextLoaded = 0; // How many text blobs have been loaded, 0, 1 or 2?
  41         var $mCacheHit = false; // Was the diff fetched from cache?
  42
  43         /**
  44          * Set this to true to add debug info to the HTML output.
  45          * Warning: this may cause RSS readers to spuriously mark articles as "new"
  46          * (bug 20601)
  47          */
  48         var $enableDebugComment = false;
  49
  50         // If true, line X is not displayed when X is 1, for example to increase
  51         // readability and conserve space with many small diffs.
  52         protected $mReducedLineNumbers = false;
  53
  54         protected $unhide = false; # show rev_deleted content if allowed
  55         /**#@-*/
  56
  57         /**
  58          * Constructor
  59          * @param $titleObj Title object that the diff is associated with
  60          * @param $old Integer: old ID we want to show and diff with.
  61          * @param $new String: either 'prev' or 'next'.
  62          * @param $rcid Integer: ??? FIXME (default 0)
  63          * @param $refreshCache boolean If set, refreshes the diff cache
  64          * @param $unhide boolean If set, allow viewing deleted revs
  65          */
  66         function __construct( $titleObj = null, $old = 0, $new = 0, $rcid = 0,
  67                 $refreshCache = false, $unhide = false )
  68         {
  69                 if ( $titleObj ) {
  70                         $this->mTitle = $titleObj;
  71                 } else {
  72                         global $wgTitle;
  73                         $this->mTitle = $wgTitle; // @TODO: get rid of this
  74                 }
  75                 wfDebug( "DifferenceEngine old '$old' new '$new' rcid '$rcid'\n" );
  76
  77                 if ( 'prev' === $new ) {
  78                         # Show diff between revision $old and the previous one.
  79                         # Get previous one from DB.
  80                         $this->mNewid = intval( $old );
  81                         $this->mOldid = $this->mTitle->getPreviousRevisionID( $this->mNewid );
  82                 } elseif ( 'next' === $new ) {
  83                         # Show diff between revision $old and the next one.
  84                         # Get next one from DB.
  85                         $this->mOldid = intval( $old );
  86                         $this->mNewid = $this->mTitle->getNextRevisionID( $this->mOldid );
  87                         if ( false === $this->mNewid ) {
  88                                 # if no result, NewId points to the newest old revision. The only newer
  89                                 # revision is cur, which is "0".
  90                                 $this->mNewid = 0;
  91                         }
  92                 } else {
  93                         $this->mOldid = intval( $old );
  94                         $this->mNewid = intval( $new );
  95                         wfRunHooks( 'NewDifferenceEngine', array( &$titleObj, &$this->mOldid, &$this->mNewid, $old, $new ) );
  96                 }
  97                 $this->mRcidMarkPatrolled = intval( $rcid );  # force it to be an integer
  98                 $this->mRefreshCache = $refreshCache;
  99                 $this->unhide = $unhide;
 100         }
 101
 102         function setReducedLineNumbers( $value = true ) {
 103                 $this->mReducedLineNumbers = $value;
 104         }
 105
 106         function getTitle() {
 107                 return $this->mTitle;
 108         }
 109
 110         function wasCacheHit() {
 111                 return $this->mCacheHit;
 112         }
 113
 114         function getOldid() {
 115                 return $this->mOldid;
 116         }
 117
 118         function getNewid() {
 119                 return $this->mNewid;
 120         }
 121
 122         /**
 123          * Look up a special:Undelete link to the given deleted revision id,
 124          * as a workaround for being unable to load deleted diffs in currently.
 125          *
 126          * @param int $id revision ID
 127          * @return mixed URL or false
 128          */
 129         function deletedLink( $id ) {
 130                 global $wgUser;
 131                 if ( $wgUser->isAllowed( 'deletedhistory' ) ) {
 132                         $dbr = wfGetDB( DB_SLAVE );
 133                         $row = $dbr->selectRow('archive', '*',
 134                                 array( 'ar_rev_id' => $id ),
 135                                 __METHOD__ );
 136                         if ( $row ) {
 137                                 $rev = Revision::newFromArchiveRow( $row );
 138                                 $title = Title::makeTitleSafe( $row->ar_namespace, $row->ar_title );
 139                                 return SpecialPage::getTitleFor( 'Undelete' )->getFullURL( array(
 140                                         'target' => $title->getPrefixedText(),
 141                                         'timestamp' => $rev->getTimestamp()
 142                                 ));
 143                         }
 144                 }
 145                 return false;
 146         }
 147
 148         /**
 149          * Build a wikitext link toward a deleted revision, if viewable.
 150          *
 151          * @param int $id revision ID
 152          * @return string wikitext fragment
 153          */
 154         function deletedIdMarker( $id ) {
 155                 $link = $this->deletedLink( $id );
 156                 if ( $link ) {
 157                         return "[$link $id]";
 158                 } else {
 159                         return $id;
 160                 }
 161         }
 162
 163         function showDiffPage( $diffOnly = false ) {
 164                 global $wgUser, $wgOut, $wgUseExternalEditor, $wgUseRCPatrol;
 165                 wfProfileIn( __METHOD__ );
 166
 167                 # Allow frames except in certain special cases
 168                 $wgOut->allowClickjacking();
 169
 170                 # If external diffs are enabled both globally and for the user,
 171                 # we'll use the application/x-external-editor interface to call
 172                 # an external diff tool like kompare, kdiff3, etc.
 173                 if ( $wgUseExternalEditor && $wgUser->getOption( 'externaldiff' ) ) {
 174                         global $wgServer, $wgScript, $wgLang;
 175                         $wgOut->disable();
 176                         header ( "Content-type: application/x-external-editor; charset=UTF-8" );
 177                         $url1 = $this->mTitle->getFullURL( array(
 178                                 'action' => 'raw',
 179                                 'oldid' => $this->mOldid
 180                         ) );
 181                         $url2 = $this->mTitle->getFullURL( array(
 182                                 'action' => 'raw',
 183                                 'oldid' => $this->mNewid
 184                         ) );
 185                         $special = $wgLang->getNsText( NS_SPECIAL );
 186                         $control = <<<CONTROL
 187                         [Process]
 188                         Type=Diff text
 189                         Engine=MediaWiki
 190                         Script={$wgServer}{$wgScript}
 191                         Special namespace={$special}
 192
 193                         [File]
 194                         Extension=wiki
 195                         URL=$url1
 196
 197                         [File 2]
 198                         Extension=wiki
 199                         URL=$url2
 200 CONTROL;
 201                         echo( $control );
 202
 203                         wfProfileOut( __METHOD__ );
 204                         return;
 205                 }
 206
 207                 $wgOut->setArticleFlag( false );
 208                 if ( !$this->loadRevisionData() ) {
 209                         // Sounds like a deleted revision... Let's see what we can do.
 210                         $deletedLink = $this->deletedLink( $this->mNewid );
 211
 212                         $t = $this->mTitle->getPrefixedText();
 213                         $d = wfMsgExt( 'missingarticle-diff', array( 'escape' ),
 214                                         $this->deletedIdMarker( $this->mOldid ),
 215                                         $this->deletedIdMarker( $this->mNewid ) );
 216                         $wgOut->setPagetitle( wfMsg( 'errorpagetitle' ) );
 217                         $wgOut->addWikiMsg( 'missing-article', "<nowiki>$t</nowiki>", "<span class='plainlinks'>$d</span>" );
 218                         wfProfileOut( __METHOD__ );
 219                         return;
 220                 }
 221
 222                 wfRunHooks( 'DiffViewHeader', array( $this, $this->mOldRev, $this->mNewRev ) );
 223
 224                 if ( $this->mNewRev->isCurrent() ) {
 225                         $wgOut->setArticleFlag( true );
 226                 }
 227
 228                 # mOldid is false if the difference engine is called with a "vague" query for
 229                 # a diff between a version V and its previous version V' AND the version V
 230                 # is the first version of that article. In that case, V' does not exist.
 231                 if ( $this->mOldid === false ) {
 232                         $this->showFirstRevision();
 233                         $this->renderNewRevision();  // should we respect $diffOnly here or not?
 234                         wfProfileOut( __METHOD__ );
 235                         return;
 236                 }
 237
 238                 $oldTitle = $this->mOldPage->getPrefixedText();
 239                 $newTitle = $this->mNewPage->getPrefixedText();
 240                 if ( $oldTitle == $newTitle ) {
 241                         $wgOut->setPageTitle( $newTitle );
 242                 } else {
 243                         $wgOut->setPageTitle( $oldTitle . ', ' . $newTitle );
 244                 }
 245                 if ( $this->mNewPage->equals( $this->mOldPage ) ) {
 246                         $wgOut->setSubtitle( wfMsgExt( 'difference', array( 'parseinline' ) ) );
 247                 } else {
 248                         $wgOut->setSubtitle( wfMsgExt( 'difference-multipage', array( 'parseinline' ) ) );
 249                 }
 250                 $wgOut->setRobotPolicy( 'noindex,nofollow' );
 251
 252                 if ( !$this->mOldPage->userCanRead() || !$this->mNewPage->userCanRead() ) {
 253                         $wgOut->loginToUse();
 254                         $wgOut->output();
 255                         $wgOut->disable();
 256                         wfProfileOut( __METHOD__ );
 257                         return;
 258                 }
 259
 260                 $sk = $wgUser->getSkin();
 261                 if ( method_exists( $sk, 'suppressQuickbar' ) ) {
 262                         $sk->suppressQuickbar();
 263                 }
 264
 265                 // Check if page is editable
 266                 $editable = $this->mNewRev->getTitle()->userCan( 'edit' );
 267                 if ( $editable && $this->mNewRev->isCurrent() && $wgUser->isAllowed( 'rollback' ) ) {
 268                         $wgOut->preventClickjacking();
 269                         $rollback = '&#160;&#160;&#160;' . $sk->generateRollback( $this->mNewRev );
 270                 } else {
 271                         $rollback = '';
 272                 }
 273
 274                 // Prepare a change patrol link, if applicable
 275                 if ( $wgUseRCPatrol && $this->mTitle->userCan( 'patrol' ) ) {
 276                         // If we've been given an explicit change identifier, use it; saves time
 277                         if ( $this->mRcidMarkPatrolled ) {
 278                                 $rcid = $this->mRcidMarkPatrolled;
 279                                 $rc = RecentChange::newFromId( $rcid );
 280                                 // Already patrolled?
 281                                 $rcid = is_object( $rc ) && !$rc->getAttribute( 'rc_patrolled' ) ? $rcid : 0;
 282                         } else {
 283                                 // Look for an unpatrolled change corresponding to this diff
 284                                 $db = wfGetDB( DB_SLAVE );
 285                                 $change = RecentChange::newFromConds(
 286                                         array(
 287                                         // Redundant user,timestamp condition so we can use the existing index
 288                                                 'rc_user_text'  => $this->mNewRev->getRawUserText(),
 289                                                 'rc_timestamp'  => $db->timestamp( $this->mNewRev->getTimestamp() ),
 290                                                 'rc_this_oldid' => $this->mNewid,
 291                                                 'rc_last_oldid' => $this->mOldid,
 292                                                 'rc_patrolled'  => 0
 293                                         ),
 294                                         __METHOD__
 295                                 );
 296                                 if ( $change instanceof RecentChange ) {
 297                                         $rcid = $change->mAttribs['rc_id'];
 298                                         $this->mRcidMarkPatrolled = $rcid;
 299                                 } else {
 300                                         // None found
 301                                         $rcid = 0;
 302                                 }
 303                         }
 304                         // Build the link
 305                         if ( $rcid ) {
 306                                 $wgOut->preventClickjacking();
 307                                 $token = $wgUser->editToken( $rcid );
 308                                 $patrol = ' <span class="patrollink">[' . $sk->link(
 309                                         $this->mTitle,
 310                                         wfMsgHtml( 'markaspatrolleddiff' ),
 311                                         array(),
 312                                         array(
 313                                                 'action' => 'markpatrolled',
 314                                                 'rcid' => $rcid,
 315                                                 'token' => $token,
 316                                         ),
 317                                         array(
 318                                                 'known',
 319                                                 'noclasses'
 320                                         )
 321                                 ) . ']</span>';
 322                         } else {
 323                                 $patrol = '';
 324                         }
 325                 } else {
 326                         $patrol = '';
 327                 }
 328
 329                 # Carry over 'diffonly' param via navigation links
 330                 if ( $diffOnly != $wgUser->getBoolOption( 'diffonly' ) ) {
 331                         $query['diffonly'] = $diffOnly;
 332                 }
 333
 334                 # Make "previous revision link"
 335                 $query['diff'] = 'prev';
 336                 $query['oldid'] = $this->mOldid;
 337                 # Cascade unhide param in links for easy deletion browsing
 338                 if ( $this->unhide ) {
 339                         $query['unhide'] = 1;
 340                 }
 341                 if ( !$this->mOldRev->getPrevious() ) {
 342                         $prevlink = '&#160;';
 343                 } else {
 344                         $prevlink = $sk->link(
 345                                 $this->mTitle,
 346                                 wfMsgHtml( 'previousdiff' ),
 347                                 array(
 348                                         'id' => 'differences-prevlink'
 349                                 ),
 350                                 $query,
 351                                 array(
 352                                         'known',
 353                                         'noclasses'
 354                                 )
 355                         );
 356                 }
 357
 358                 # Make "next revision link"
 359                 $query['diff'] = 'next';
 360                 $query['oldid'] = $this->mNewid;
 361                 # Skip next link on the top revision
 362                 if ( $this->mNewRev->isCurrent() ) {
 363                         $nextlink = '&#160;';
 364                 } else {
 365                         $nextlink = $sk->link(
 366                                 $this->mTitle,
 367                                 wfMsgHtml( 'nextdiff' ),
 368                                 array(
 369                                         'id' => 'differences-nextlink'
 370                                 ),
 371                                 $query,
 372                                 array(
 373                                         'known',
 374                                         'noclasses'
 375                                 )
 376                         );
 377                 }
 378
 379                 $oldminor = '';
 380                 $newminor = '';
 381
 382                 if ( $this->mOldRev->isMinor() ) {
 383                         $oldminor = ChangesList::flag( 'minor' );
 384                 }
 385                 if ( $this->mNewRev->isMinor() ) {
 386                         $newminor = ChangesList::flag( 'minor' );
 387                 }
 388
 389                 # Handle RevisionDelete links...
 390                 $ldel = $this->revisionDeleteLink( $this->mOldRev );
 391                 $rdel = $this->revisionDeleteLink( $this->mNewRev );
 392
 393                 $oldHeader = '<div id="mw-diff-otitle1"><strong>' . $this->mOldtitle . '</strong></div>' .
 394                         '<div id="mw-diff-otitle2">' .
 395                                 $sk->revUserTools( $this->mOldRev, !$this->unhide ) . '</div>' .
 396                         '<div id="mw-diff-otitle3">' . $oldminor .
 397                                 $sk->revComment( $this->mOldRev, !$diffOnly, !$this->unhide ) . $ldel . '</div>' .
 398                         '<div id="mw-diff-otitle4">' . $prevlink . '</div>';
 399                 $newHeader = '<div id="mw-diff-ntitle1"><strong>' . $this->mNewtitle . '</strong></div>' .
 400                         '<div id="mw-diff-ntitle2">' . $sk->revUserTools( $this->mNewRev, !$this->unhide ) .
 401                                 " $rollback</div>" .
 402                         '<div id="mw-diff-ntitle3">' . $newminor .
 403                                 $sk->revComment( $this->mNewRev, !$diffOnly, !$this->unhide ) . $rdel . '</div>' .
 404                         '<div id="mw-diff-ntitle4">' . $nextlink . $patrol . '</div>';
 405
 406                 # Check if this user can see the revisions
 407                 $allowed = $this->mOldRev->userCan( Revision::DELETED_TEXT )
 408                         && $this->mNewRev->userCan( Revision::DELETED_TEXT );
 409                 # Check if one of the revisions is deleted/suppressed
 410                 $deleted = $suppressed = false;
 411                 if ( $this->mOldRev->isDeleted( Revision::DELETED_TEXT ) ) {
 412                         $deleted = true; // old revisions text is hidden
 413                         if ( $this->mOldRev->isDeleted( Revision::DELETED_RESTRICTED ) )
 414                                 $suppressed = true; // also suppressed
 415                 }
 416                 if ( $this->mNewRev->isDeleted( Revision::DELETED_TEXT ) ) {
 417                         $deleted = true; // new revisions text is hidden
 418                         if ( $this->mNewRev->isDeleted( Revision::DELETED_RESTRICTED ) )
 419                                 $suppressed = true; // also suppressed
 420                 }
 421                 # If the diff cannot be shown due to a deleted revision, then output
 422                 # the diff header and links to unhide (if available)...
 423                 if ( $deleted && ( !$this->unhide || !$allowed ) ) {
 424                         $this->showDiffStyle();
 425                         $multi = $this->getMultiNotice();
 426                         $wgOut->addHTML( $this->addHeader( '', $oldHeader, $newHeader, $multi ) );
 427                         if ( !$allowed ) {
 428                                 $msg = $suppressed ? 'rev-suppressed-no-diff' : 'rev-deleted-no-diff';
 429                                 # Give explanation for why revision is not visible
 430                                 $wgOut->wrapWikiMsg( "<div id='mw-$msg' class='mw-warning plainlinks'>\n$1\n</div>\n",
 431                                         array( $msg ) );
 432                         } else {
 433                                 # Give explanation and add a link to view the diff...
 434                                 $link = $this->mTitle->getFullUrl( array(
 435                                         'diff' => $this->mNewid,
 436                                         'oldid' => $this->mOldid,
 437                                         'unhide' => 1
 438                                 ) );
 439                                 $msg = $suppressed ? 'rev-suppressed-unhide-diff' : 'rev-deleted-unhide-diff';
 440                                 $wgOut->wrapWikiMsg( "<div id='mw-$msg' class='mw-warning plainlinks'>\n$1\n</div>\n", array( $msg, $link ) );
 441                         }
 442                 # Otherwise, output a regular diff...
 443                 } else {
 444                         # Add deletion notice if the user is viewing deleted content
 445                         $notice = '';
 446                         if ( $deleted ) {
 447                                 $msg = $suppressed ? 'rev-suppressed-diff-view' : 'rev-deleted-diff-view';
 448                                 $notice = "<div id='mw-$msg' class='mw-warning plainlinks'>\n" . wfMsgExt( $msg, 'parseinline' ) . "</div>\n";
 449                         }
 450                         $this->showDiff( $oldHeader, $newHeader, $notice );
 451                         if ( !$diffOnly ) {
 452                                 $this->renderNewRevision();
 453                         }
 454                 }
 455                 wfProfileOut( __METHOD__ );
 456         }
 457
 458         /**
 459          * @param $rev Revision
 460          * @return String
 461          */
 462         protected function revisionDeleteLink( $rev ) {
 463                 global $wgUser;
 464                 $link = '';
 465                 $canHide = $wgUser->isAllowed( 'deleterevision' );
 466                 // Show del/undel link if:
 467                 // (a) the user can delete revisions, or
 468                 // (b) the user can view deleted revision *and* this one is deleted
 469                 if ( $canHide || ( $rev->getVisibility() && $wgUser->isAllowed( 'deletedhistory' ) ) ) {
 470                         $sk = $wgUser->getSkin();
 471                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED ) ) {
 472                                 $link = $sk->revDeleteLinkDisabled( $canHide ); // revision was hidden from sysops
 473                         } else {
 474                                 $query = array(
 475                                         'type'   => 'revision',
 476                                         'target' => $rev->mTitle->getPrefixedDbkey(),
 477                                         'ids'    => $rev->getId()
 478                                 );
 479                                 $link = $sk->revDeleteLink( $query,
 480                                         $rev->isDeleted( Revision::DELETED_RESTRICTED ), $canHide );
 481                         }
 482                         $link = '&#160;&#160;&#160;' . $link . ' ';
 483                 }
 484                 return $link;
 485         }
 486
 487         /**
 488          * Show the new revision of the page.
 489          */
 490         function renderNewRevision() {
 491                 global $wgOut, $wgUser;
 492                 wfProfileIn( __METHOD__ );
 493                 # Add "current version as of X" title
 494                 $wgOut->addHTML( "<hr /><h2>{$this->mPagetitle}</h2>\n" );
 495                 # Page content may be handled by a hooked call instead...
 496                 if ( wfRunHooks( 'ArticleContentOnDiff', array( $this, $wgOut ) ) ) {
 497                         # Use the current version parser cache if applicable
 498                         $pCache = true;
 499                         if ( !$this->mNewRev->isCurrent() ) {
 500                                 $oldEditSectionSetting = $wgOut->parserOptions()->setEditSection( false );
 501                                 $pCache = false;
 502                         }
 503
 504                         $this->loadNewText();
 505                         $wgOut->setRevisionId( $this->mNewRev->getId() );
 506
 507                         if ( $this->mTitle->isCssJsSubpage() || $this->mTitle->isCssOrJsPage() ) {
 508                                 // Stolen from Article::view --AG 2007-10-11
 509                                 // Give hooks a chance to customise the output
 510                                 // @TODO: standardize this crap into one function
 511                                 if ( wfRunHooks( 'ShowRawCssJs', array( $this->mNewtext, $this->mTitle, $wgOut ) ) ) {
 512                                         // Wrap the whole lot in a <pre> and don't parse
 513                                         $m = array();
 514                                         preg_match( '!\.(css|js)$!u', $this->mTitle->getText(), $m );
 515                                         $wgOut->addHTML( "<pre class=\"mw-code mw-{$m[1]}\" dir=\"ltr\">\n" );
 516                                         $wgOut->addHTML( htmlspecialchars( $this->mNewtext ) );
 517                                         $wgOut->addHTML( "\n</pre>\n" );
 518                                 }
 519                         } elseif ( $pCache ) {
 520                                 $article = new Article( $this->mTitle, 0 );
 521                                 $pOutput = ParserCache::singleton()->get( $article, $wgOut->parserOptions() );
 522                                 if( $pOutput ) {
 523                                         $wgOut->addParserOutput( $pOutput );
 524                                 } else {
 525                                         $article->doViewParse();
 526                                 }
 527                         } else {
 528                                 $wgOut->addWikiTextTidy( $this->mNewtext );
 529                         }
 530
 531                         if ( !$this->mNewRev->isCurrent() ) {
 532                                 $wgOut->parserOptions()->setEditSection( $oldEditSectionSetting );
 533                         }
 534                 }
 535                 # Add redundant patrol link on bottom...
 536                 if ( $this->mRcidMarkPatrolled && $this->mTitle->quickUserCan( 'patrol' ) ) {
 537                         $sk = $wgUser->getSkin();
 538                         $token = $wgUser->editToken( $this->mRcidMarkPatrolled );
 539                         $wgOut->preventClickjacking();
 540                         $wgOut->addHTML(
 541                                 "<div class='patrollink'>[" . $sk->link(
 542                                         $this->mTitle,
 543                                         wfMsgHtml( 'markaspatrolleddiff' ),
 544                                         array(),
 545                                         array(
 546                                                 'action'        => 'markpatrolled',
 547                                                 'rcid'          => $this->mRcidMarkPatrolled,
 548                                                 'token'         => $token,
 549                                         )
 550                                 ) . ']</div>'
 551                          );
 552                 }
 553
 554                 wfProfileOut( __METHOD__ );
 555         }
 556
 557         /**
 558          * Show the first revision of an article. Uses normal diff headers in
 559          * contrast to normal "old revision" display style.
 560          */
 561         function showFirstRevision() {
 562                 global $wgOut, $wgUser;
 563                 wfProfileIn( __METHOD__ );
 564
 565                 # Get article text from the DB
 566                 #
 567                 if ( ! $this->loadNewText() ) {
 568                         $t = $this->mTitle->getPrefixedText();
 569                         $d = wfMsgExt( 'missingarticle-diff', array( 'escape' ),
 570                                         $this->deletedIdMarker( $this->mOldid ),
 571                                         $this->deletedIdMarker( $this->mNewid ) );
 572                         $wgOut->setPagetitle( wfMsg( 'errorpagetitle' ) );
 573                         $wgOut->addWikiMsg( 'missing-article', "<nowiki>$t</nowiki>", "<span class='plainlinks'>$d</span>" );
 574                         wfProfileOut( __METHOD__ );
 575                         return;
 576                 }
 577                 if ( $this->mNewRev->isCurrent() ) {
 578                         $wgOut->setArticleFlag( true );
 579                 }
 580
 581                 # Check if user is allowed to look at this page. If not, bail out.
 582                 #
 583                 if ( !$this->mTitle->userCanRead() ) {
 584                         $wgOut->loginToUse();
 585                         $wgOut->output();
 586                         wfProfileOut( __METHOD__ );
 587                         throw new MWException( "Permission Error: you do not have access to view this page" );
 588                 }
 589
 590                 # Prepare the header box
 591                 #
 592                 $sk = $wgUser->getSkin();
 593
 594                 $next = $this->mTitle->getNextRevisionID( $this->mNewid );
 595                 if ( !$next ) {
 596                         $nextlink = '';
 597                 } else {
 598                         $nextlink = '<br />' . $sk->link(
 599                                 $this->mTitle,
 600                                 wfMsgHtml( 'nextdiff' ),
 601                                 array(
 602                                         'id' => 'differences-nextlink'
 603                                 ),
 604                                 array(
 605                                         'diff' => 'next',
 606                                         'oldid' => $this->mNewid,
 607                                 ),
 608                                 array(
 609                                         'known',
 610                                         'noclasses'
 611                                 )
 612                         );
 613                 }
 614                 $header = "<div class=\"firstrevisionheader\" style=\"text-align: center\">" .
 615                         $sk->revUserTools( $this->mNewRev ) . "<br />" . $sk->revComment( $this->mNewRev ) . $nextlink . "</div>\n";
 616
 617                 $wgOut->addHTML( $header );
 618
 619                 $wgOut->setSubtitle( wfMsgExt( 'difference', array( 'parseinline' ) ) );
 620                 $wgOut->setRobotPolicy( 'noindex,nofollow' );
 621
 622                 wfProfileOut( __METHOD__ );
 623         }
 624
 625         /**
 626          * Get the diff text, send it to $wgOut
 627          * Returns false if the diff could not be generated, otherwise returns true
 628          */
 629         function showDiff( $otitle, $ntitle, $notice = '' ) {
 630                 global $wgOut;
 631                 $diff = $this->getDiff( $otitle, $ntitle, $notice );
 632                 if ( $diff === false ) {
 633                         $wgOut->addWikiMsg( 'missing-article', "<nowiki>(fixme, bug)</nowiki>", '' );
 634                         return false;
 635                 } else {
 636                         $this->showDiffStyle();
 637                         $wgOut->addHTML( $diff );
 638                         return true;
 639                 }
 640         }
 641
 642         /**
 643          * Add style sheets and supporting JS for diff display.
 644          */
 645         function showDiffStyle() {
 646                 global $wgOut;
 647                 $wgOut->addModuleStyles( 'mediawiki.legacy.diff' );
 648         }
 649
 650         /**
 651          * Get complete diff table, including header
 652          *
 653          * @param $otitle Title: old title
 654          * @param $ntitle Title: new title
 655          * @param $notice String: HTML between diff header and body
 656          * @return mixed
 657          */
 658         function getDiff( $otitle, $ntitle, $notice = '' ) {
 659                 $body = $this->getDiffBody();
 660                 if ( $body === false ) {
 661                         return false;
 662                 } else {
 663                         $multi = $this->getMultiNotice();
 664                         return $this->addHeader( $body, $otitle, $ntitle, $multi, $notice );
 665                 }
 666         }
 667
 668         /**
 669          * Get the diff table body, without header
 670          *
 671          * @return mixed (string/false)
 672          */
 673         public function getDiffBody() {
 674                 global $wgMemc;
 675                 wfProfileIn( __METHOD__ );
 676                 $this->mCacheHit = true;
 677                 // Check if the diff should be hidden from this user
 678                 if ( !$this->loadRevisionData() ) {
 679                         wfProfileOut( __METHOD__ );
 680                         return false;
 681                 } elseif ( $this->mOldRev && !$this->mOldRev->userCan( Revision::DELETED_TEXT ) ) {
 682                         wfProfileOut( __METHOD__ );
 683                         return false;
 684                 } elseif ( $this->mNewRev && !$this->mNewRev->userCan( Revision::DELETED_TEXT ) ) {
 685                         wfProfileOut( __METHOD__ );
 686                         return false;
 687                 }
 688                 // Short-circuit
 689                 if ( $this->mOldRev && $this->mNewRev
 690                         && $this->mOldRev->getID() == $this->mNewRev->getID() )
 691                 {
 692                         wfProfileOut( __METHOD__ );
 693                         return '';
 694                 }
 695                 // Cacheable?
 696                 $key = false;
 697                 if ( $this->mOldid && $this->mNewid ) {
 698                         $key = wfMemcKey( 'diff', 'version', MW_DIFF_VERSION,
 699                                 'oldid', $this->mOldid, 'newid', $this->mNewid );
 700                         // Try cache
 701                         if ( !$this->mRefreshCache ) {
 702                                 $difftext = $wgMemc->get( $key );
 703                                 if ( $difftext ) {
 704                                         wfIncrStats( 'diff_cache_hit' );
 705                                         $difftext = $this->localiseLineNumbers( $difftext );
 706                                         $difftext .= "\n<!-- diff cache key $key -->\n";
 707                                         wfProfileOut( __METHOD__ );
 708                                         return $difftext;
 709                                 }
 710                         } // don't try to load but save the result
 711                 }
 712                 $this->mCacheHit = false;
 713
 714                 // Loadtext is permission safe, this just clears out the diff
 715                 if ( !$this->loadText() ) {
 716                         wfProfileOut( __METHOD__ );
 717                         return false;
 718                 }
 719
 720                 $difftext = $this->generateDiffBody( $this->mOldtext, $this->mNewtext );
 721
 722                 // Save to cache for 7 days
 723                 if ( !wfRunHooks( 'AbortDiffCache', array( &$this ) ) ) {
 724                         wfIncrStats( 'diff_uncacheable' );
 725                 } elseif ( $key !== false && $difftext !== false ) {
 726                         wfIncrStats( 'diff_cache_miss' );
 727                         $wgMemc->set( $key, $difftext, 7 * 86400 );
 728                 } else {
 729                         wfIncrStats( 'diff_uncacheable' );
 730                 }
 731                 // Replace line numbers with the text in the user's language
 732                 if ( $difftext !== false ) {
 733                         $difftext = $this->localiseLineNumbers( $difftext );
 734                 }
 735                 wfProfileOut( __METHOD__ );
 736                 return $difftext;
 737         }
 738
 739         /**
 740          * Make sure the proper modules are loaded before we try to
 741          * make the diff
 742          */
 743         private function initDiffEngines() {
 744                 global $wgExternalDiffEngine;
 745                 if ( $wgExternalDiffEngine == 'wikidiff' && !function_exists( 'wikidiff_do_diff' ) ) {
 746                         wfProfileIn( __METHOD__ . '-php_wikidiff.so' );
 747                         wfDl( 'php_wikidiff' );
 748                         wfProfileOut( __METHOD__ . '-php_wikidiff.so' );
 749                 }
 750                 else if ( $wgExternalDiffEngine == 'wikidiff2' && !function_exists( 'wikidiff2_do_diff' ) ) {
 751                         wfProfileIn( __METHOD__ . '-php_wikidiff2.so' );
 752                         wfDl( 'wikidiff2' );
 753                         wfProfileOut( __METHOD__ . '-php_wikidiff2.so' );
 754                 }
 755         }
 756
 757         /**
 758          * Generate a diff, no caching
 759          *
 760          * @param $otext String: old text, must be already segmented
 761          * @param $ntext String: new text, must be already segmented
 762          */
 763         function generateDiffBody( $otext, $ntext ) {
 764                 global $wgExternalDiffEngine, $wgContLang;
 765
 766                 $otext = str_replace( "\r\n", "\n", $otext );
 767                 $ntext = str_replace( "\r\n", "\n", $ntext );
 768
 769                 $this->initDiffEngines();
 770
 771                 if ( $wgExternalDiffEngine == 'wikidiff' && function_exists( 'wikidiff_do_diff' ) ) {
 772                         # For historical reasons, external diff engine expects
 773                         # input text to be HTML-escaped already
 774                         $otext = htmlspecialchars ( $wgContLang->segmentForDiff( $otext ) );
 775                         $ntext = htmlspecialchars ( $wgContLang->segmentForDiff( $ntext ) );
 776                         return $wgContLang->unsegmentForDiff( wikidiff_do_diff( $otext, $ntext, 2 ) ) .
 777                         $this->debug( 'wikidiff1' );
 778                 }
 779
 780                 if ( $wgExternalDiffEngine == 'wikidiff2' && function_exists( 'wikidiff2_do_diff' ) ) {
 781                         # Better external diff engine, the 2 may some day be dropped
 782                         # This one does the escaping and segmenting itself
 783                         wfProfileIn( 'wikidiff2_do_diff' );
 784                         $text = wikidiff2_do_diff( $otext, $ntext, 2 );
 785                         $text .= $this->debug( 'wikidiff2' );
 786                         wfProfileOut( 'wikidiff2_do_diff' );
 787                         return $text;
 788                 }
 789                 if ( $wgExternalDiffEngine != 'wikidiff3' && $wgExternalDiffEngine !== false ) {
 790                         # Diff via the shell
 791                         global $wgTmpDirectory;
 792                         $tempName1 = tempnam( $wgTmpDirectory, 'diff_' );
 793                         $tempName2 = tempnam( $wgTmpDirectory, 'diff_' );
 794
 795                         $tempFile1 = fopen( $tempName1, "w" );
 796                         if ( !$tempFile1 ) {
 797                                 wfProfileOut( __METHOD__ );
 798                                 return false;
 799                         }
 800                         $tempFile2 = fopen( $tempName2, "w" );
 801                         if ( !$tempFile2 ) {
 802                                 wfProfileOut( __METHOD__ );
 803                                 return false;
 804                         }
 805                         fwrite( $tempFile1, $otext );
 806                         fwrite( $tempFile2, $ntext );
 807                         fclose( $tempFile1 );
 808                         fclose( $tempFile2 );
 809                         $cmd = wfEscapeShellArg( $wgExternalDiffEngine, $tempName1, $tempName2 );
 810                         wfProfileIn( __METHOD__ . "-shellexec" );
 811                         $difftext = wfShellExec( $cmd );
 812                         $difftext .= $this->debug( "external $wgExternalDiffEngine" );
 813                         wfProfileOut( __METHOD__ . "-shellexec" );
 814                         unlink( $tempName1 );
 815                         unlink( $tempName2 );
 816                         wfProfileOut( __METHOD__ );
 817                         return $difftext;
 818                 }
 819
 820                 # Native PHP diff
 821                 $ota = explode( "\n", $wgContLang->segmentForDiff( $otext ) );
 822                 $nta = explode( "\n", $wgContLang->segmentForDiff( $ntext ) );
 823                 $diffs = new Diff( $ota, $nta );
 824                 $formatter = new TableDiffFormatter();
 825                 $difftext = $wgContLang->unsegmentForDiff( $formatter->format( $diffs ) ) .
 826                 wfProfileOut( __METHOD__ );
 827                 return $difftext;
 828         }
 829
 830         /**
 831          * Generate a debug comment indicating diff generating time,
 832          * server node, and generator backend.
 833          */
 834         protected function debug( $generator = "internal" ) {
 835                 global $wgShowHostnames;
 836                 if ( !$this->enableDebugComment ) {
 837                         return '';
 838                 }
 839                 $data = array( $generator );
 840                 if ( $wgShowHostnames ) {
 841                         $data[] = wfHostname();
 842                 }
 843                 $data[] = wfTimestamp( TS_DB );
 844                 return "<!-- diff generator: " .
 845                 implode( " ",
 846                 array_map(
 847                                         "htmlspecialchars",
 848                 $data ) ) .
 849                         " -->\n";
 850         }
 851
 852         /**
 853          * Replace line numbers with the text in the user's language
 854          */
 855         function localiseLineNumbers( $text ) {
 856                 return preg_replace_callback( '/<!--LINE (\d+)-->/',
 857                 array( &$this, 'localiseLineNumbersCb' ), $text );
 858         }
 859
 860         function localiseLineNumbersCb( $matches ) {
 861                 global $wgLang;
 862                 if ( $matches[1] === '1' && $this->mReducedLineNumbers ) return '';
 863                 return wfMsgExt( 'lineno', 'escape', $wgLang->formatNum( $matches[1] ) );
 864         }
 865
 866
 867         /**
 868          * If there are revisions between the ones being compared, return a note saying so.
 869          * @return string
 870          */
 871         function getMultiNotice() {
 872                 if ( !is_object( $this->mOldRev ) || !is_object( $this->mNewRev ) ) {
 873                         return '';
 874                 } elseif ( !$this->mOldPage->equals( $this->mNewPage ) ) {
 875                         // Comparing two different pages? Count would be meaningless.
 876                         return '';
 877                 }
 878
 879                 if ( $this->mOldRev->getTimestamp() > $this->mNewRev->getTimestamp() ) {
 880                         $oldRev = $this->mNewRev; // flip
 881                         $newRev = $this->mOldRev; // flip
 882                 } else { // normal case
 883                         $oldRev = $this->mOldRev;
 884                         $newRev = $this->mNewRev;
 885                 }
 886
 887                 $nEdits = $this->mTitle->countRevisionsBetween( $oldRev, $newRev );
 888                 if ( $nEdits > 0 ) {
 889                         $limit = 100; // use diff-multi-manyusers if too many users
 890                         $numUsers = $this->mTitle->countAuthorsBetween( $oldRev, $newRev, $limit );
 891                         return self::intermediateEditsMsg( $nEdits, $numUsers, $limit );
 892                 }
 893                 return ''; // nothing
 894         }
 895
 896         /**
 897          * Get a notice about how many intermediate edits and users there are
 898          * @param $numEdits int
 899          * @param $numUsers int
 900          * @param $limit int
 901          * @return string
 902          */
 903         public static function intermediateEditsMsg( $numEdits, $numUsers, $limit ) {
 904                 global $wgLang;
 905                 if ( $numUsers > $limit ) {
 906                         $msg = 'diff-multi-manyusers';
 907                         $numUsers = $limit;
 908                 } else {
 909                         $msg = 'diff-multi';
 910                 }
 911                 return wfMsgExt( $msg, 'parseinline',
 912                         $wgLang->formatnum( $numEdits ), $wgLang->formatnum( $numUsers ) );
 913         }
 914
 915         /**
 916          * Add the header to a diff body
 917          */
 918         static function addHeader( $diff, $otitle, $ntitle, $multi = '', $notice = '' ) {
 919                 $header = "<table class='diff'>";
 920                 if ( $diff ) { // Safari/Chrome show broken output if cols not used
 921                         $header .= "
 922                         <col class='diff-marker' />
 923                         <col class='diff-content' />
 924                         <col class='diff-marker' />
 925                         <col class='diff-content' />";
 926                         $colspan = 2;
 927                         $multiColspan = 4;
 928                 } else {
 929                         $colspan = 1;
 930                         $multiColspan = 2;
 931                 }
 932                 $header .= "
 933                 <tr valign='top'>
 934                 <td colspan='$colspan' class='diff-otitle'>{$otitle}</td>
 935                 <td colspan='$colspan' class='diff-ntitle'>{$ntitle}</td>
 936                 </tr>";
 937
 938                 if ( $multi != '' ) {
 939                         $header .= "<tr><td colspan='{$multiColspan}' align='center' class='diff-multi'>{$multi}</td></tr>";
 940                 }
 941                 if ( $notice != '' ) {
 942                         $header .= "<tr><td colspan='{$multiColspan}' align='center'>{$notice}</td></tr>";
 943                 }
 944
 945                 return $header . $diff . "</table>";
 946         }
 947
 948         /**
 949          * Use specified text instead of loading from the database
 950          */
 951         function setText( $oldText, $newText ) {
 952                 $this->mOldtext = $oldText;
 953                 $this->mNewtext = $newText;
 954                 $this->mTextLoaded = 2;
 955                 $this->mRevisionsLoaded = true;
 956         }
 957
 958         /**
 959          * Load revision metadata for the specified articles. If newid is 0, then compare
 960          * the old article in oldid to the current article; if oldid is 0, then
 961          * compare the current article to the immediately previous one (ignoring the
 962          * value of newid).
 963          *
 964          * If oldid is false, leave the corresponding revision object set
 965          * to false. This is impossible via ordinary user input, and is provided for
 966          * API convenience.
 967          */
 968         function loadRevisionData() {
 969                 global $wgLang, $wgUser;
 970                 if ( $this->mRevisionsLoaded ) {
 971                         return true;
 972                 } else {
 973                         // Whether it succeeds or fails, we don't want to try again
 974                         $this->mRevisionsLoaded = true;
 975                 }
 976
 977                 // Load the new revision object
 978                 $this->mNewRev = $this->mNewid
 979                         ? Revision::newFromId( $this->mNewid )
 980                         : Revision::newFromTitle( $this->mTitle );
 981                 if ( !$this->mNewRev instanceof Revision )
 982                         return false;
 983
 984                 // Update the new revision ID in case it was 0 (makes life easier doing UI stuff)
 985                 $this->mNewid = $this->mNewRev->getId();
 986
 987                 // Check if page is editable
 988                 $editable = $this->mNewRev->getTitle()->userCan( 'edit' );
 989
 990                 // Set assorted variables
 991                 $timestamp = $wgLang->timeanddate( $this->mNewRev->getTimestamp(), true );
 992                 $dateofrev = $wgLang->date( $this->mNewRev->getTimestamp(), true );
 993                 $timeofrev = $wgLang->time( $this->mNewRev->getTimestamp(), true );
 994                 $this->mNewPage = $this->mNewRev->getTitle();
 995                 if ( $this->mNewRev->isCurrent() ) {
 996                         $newLink = $this->mNewPage->escapeLocalUrl( array(
 997                                 'oldid' => $this->mNewid
 998                         ) );
 999                         $this->mPagetitle = htmlspecialchars( wfMsg(
1000                                 'currentrev-asof',
1001                                 $timestamp,
1002                                 $dateofrev,
1003                                 $timeofrev
1004                         ) );
1005                         $newEdit = $this->mNewPage->escapeLocalUrl( array(
1006                                 'action' => 'edit'
1007                         ) );
1008
1009                         $this->mNewtitle = "<a href='$newLink'>{$this->mPagetitle}</a>";
1010                         $this->mNewtitle .= " (<a href='$newEdit'>" . wfMsgHtml( $editable ? 'editold' : 'viewsourceold' ) . "</a>)";
1011                 } else {
1012                         $newLink = $this->mNewPage->escapeLocalUrl( array(
1013                                 'oldid' => $this->mNewid
1014                         ) );
1015                         $newEdit = $this->mNewPage->escapeLocalUrl( array(
1016                                 'action' => 'edit',
1017                                 'oldid' => $this->mNewid
1018                         ) );
1019                         $this->mPagetitle = htmlspecialchars( wfMsg(
1020                                 'revisionasof',
1021                                 $timestamp,
1022                                 $dateofrev,
1023                                 $timeofrev
1024                         ) );
1025
1026                         $this->mNewtitle = "<a href='$newLink'>{$this->mPagetitle}</a>";
1027                         $this->mNewtitle .= " (<a href='$newEdit'>" . wfMsgHtml( $editable ? 'editold' : 'viewsourceold' ) . "</a>)";
1028                 }
1029                 if ( !$this->mNewRev->userCan( Revision::DELETED_TEXT ) ) {
1030                         $this->mNewtitle = "<span class='history-deleted'>{$this->mPagetitle}</span>";
1031                 } else if ( $this->mNewRev->isDeleted( Revision::DELETED_TEXT ) ) {
1032                         $this->mNewtitle = "<span class='history-deleted'>{$this->mNewtitle}</span>";
1033                 }
1034
1035                 // Load the old revision object
1036                 $this->mOldRev = false;
1037                 if ( $this->mOldid ) {
1038                         $this->mOldRev = Revision::newFromId( $this->mOldid );
1039                 } elseif ( $this->mOldid === 0 ) {
1040                         $rev = $this->mNewRev->getPrevious();
1041                         if ( $rev ) {
1042                                 $this->mOldid = $rev->getId();
1043                                 $this->mOldRev = $rev;
1044                         } else {
1045                                 // No previous revision; mark to show as first-version only.
1046                                 $this->mOldid = false;
1047                                 $this->mOldRev = false;
1048                         }
1049                 } /* elseif ( $this->mOldid === false ) leave mOldRev false; */
1050
1051                 if ( is_null( $this->mOldRev ) ) {
1052                         return false;
1053                 }
1054
1055                 if ( $this->mOldRev ) {
1056                         $this->mOldPage = $this->mOldRev->getTitle();
1057
1058                         $t = $wgLang->timeanddate( $this->mOldRev->getTimestamp(), true );
1059                         $dateofrev = $wgLang->date( $this->mOldRev->getTimestamp(), true );
1060                         $timeofrev = $wgLang->time( $this->mOldRev->getTimestamp(), true );
1061                         $oldLink = $this->mOldPage->escapeLocalUrl( array(
1062                                 'oldid' => $this->mOldid
1063                         ) );
1064                         $oldEdit = $this->mOldPage->escapeLocalUrl( array(
1065                                 'action' => 'edit',
1066                                 'oldid' => $this->mOldid
1067                         ) );
1068                         $this->mOldPagetitle = htmlspecialchars( wfMsg( 'revisionasof', $t, $dateofrev, $timeofrev ) );
1069
1070                         $this->mOldtitle = "<a href='$oldLink'>{$this->mOldPagetitle}</a>"
1071                         . " (<a href='$oldEdit'>" . wfMsgHtml( $editable ? 'editold' : 'viewsourceold' ) . "</a>)";
1072                         // Add an "undo" link
1073                         if ( $editable && !$this->mOldRev->isDeleted( Revision::DELETED_TEXT ) && !$this->mNewRev->isDeleted( Revision::DELETED_TEXT ) ) {
1074                                 $undoLink = Html::element( 'a', array(
1075                                         'href' => $this->mNewPage->getLocalUrl( array(
1076                                                 'action' => 'edit',
1077                                                 'undoafter' => $this->mOldid,
1078                                                 'undo' => $this->mNewid ) ),
1079                                         'title' => $wgUser->getSkin()->titleAttrib( 'undo' )
1080                                 ), wfMsg( 'editundo' ) );
1081                                 $this->mNewtitle .= ' (' . $undoLink . ')';
1082                         }
1083
1084                         if ( !$this->mOldRev->userCan( Revision::DELETED_TEXT ) ) {
1085                                 $this->mOldtitle = '<span class="history-deleted">' . $this->mOldPagetitle . '</span>';
1086                         } else if ( $this->mOldRev->isDeleted( Revision::DELETED_TEXT ) ) {
1087                                 $this->mOldtitle = '<span class="history-deleted">' . $this->mOldtitle . '</span>';
1088                         }
1089                 }
1090
1091                 return true;
1092         }
1093
1094         /**
1095          * Load the text of the revisions, as well as revision data.
1096          */
1097         function loadText() {
1098                 if ( $this->mTextLoaded == 2 ) {
1099                         return true;
1100                 } else {
1101                         // Whether it succeeds or fails, we don't want to try again
1102                         $this->mTextLoaded = 2;
1103                 }
1104
1105                 if ( !$this->loadRevisionData() ) {
1106                         return false;
1107                 }
1108                 if ( $this->mOldRev ) {
1109                         $this->mOldtext = $this->mOldRev->getText( Revision::FOR_THIS_USER );
1110                         if ( $this->mOldtext === false ) {
1111                                 return false;
1112                         }
1113                 }
1114                 if ( $this->mNewRev ) {
1115                         $this->mNewtext = $this->mNewRev->getText( Revision::FOR_THIS_USER );
1116                         if ( $this->mNewtext === false ) {
1117                                 return false;
1118                         }
1119                 }
1120                 return true;
1121         }
1122
1123         /**
1124          * Load the text of the new revision, not the old one
1125          */
1126         function loadNewText() {
1127                 if ( $this->mTextLoaded >= 1 ) {
1128                         return true;
1129                 } else {
1130                         $this->mTextLoaded = 1;
1131                 }
1132                 if ( !$this->loadRevisionData() ) {
1133                         return false;
1134                 }
1135                 $this->mNewtext = $this->mNewRev->getText( Revision::FOR_THIS_USER );
1136                 return true;
1137         }
1138 }