includes/actions/InfoAction.php

   1 <?php
   2 /**
   3  * Displays information about a page.
   4  *
   5  * Copyright © 2011 Alexandre Emsenhuber
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  20  *
  21  * @file
  22  * @ingroup Actions
  23  */
  24
  25 class InfoAction extends FormlessAction {
  26         /**
  27          * Returns the name of the action this object responds to.
  28          *
  29          * @return string lowercase
  30          */
  31         public function getName() {
  32                 return 'info';
  33         }
  34
  35         /**
  36          * Whether this action can still be executed by a blocked user.
  37          *
  38          * @return bool
  39          */
  40         public function requiresUnblock() {
  41                 return false;
  42         }
  43
  44         /**
  45          * Whether this action requires the wiki not to be locked.
  46          *
  47          * @return bool
  48          */
  49         public function requiresWrite() {
  50                 return false;
  51         }
  52
  53         /**
  54          * Shows page information on GET request.
  55          *
  56          * @return string Page information that will be added to the output
  57          */
  58         public function onView() {
  59                 $content = '';
  60
  61                 // Validate revision
  62                 $oldid = $this->page->getOldID();
  63                 if ( $oldid ) {
  64                         $revision = $this->page->getRevisionFetched();
  65
  66                         // Revision is missing
  67                         if ( $revision === null ) {
  68                                 return $this->msg( 'missing-revision', $oldid )->parse();
  69                         }
  70
  71                         // Revision is not current
  72                         if ( !$revision->isCurrent() ) {
  73                                 return $this->msg( 'pageinfo-not-current' )->plain();
  74                         }
  75                 }
  76
  77                 // Page header
  78                 if ( !$this->msg( 'pageinfo-header' )->isDisabled() ) {
  79                         $content .= $this->msg( 'pageinfo-header' )->parse();
  80                 }
  81
  82                 // Hide "This page is a member of # hidden categories" explanation
  83                 $content .= Html::element( 'style', array(),
  84                         '.mw-hiddenCategoriesExplanation { display: none; }' );
  85
  86                 // Hide "Templates used on this page" explanation
  87                 $content .= Html::element( 'style', array(),
  88                         '.mw-templatesUsedExplanation { display: none; }' );
  89
  90                 // Get page information
  91                 $pageInfo = $this->pageInfo();
  92
  93                 // Allow extensions to add additional information
  94                 wfRunHooks( 'InfoAction', array( $this->getContext(), &$pageInfo ) );
  95
  96                 // Render page information
  97                 foreach ( $pageInfo as $header => $infoTable ) {
  98                         $content .= $this->makeHeader( $this->msg( "pageinfo-${header}" )->escaped() );
  99                         $table = '';
 100                         foreach ( $infoTable as $infoRow ) {
 101                                 $name = ( $infoRow[0] instanceof Message ) ? $infoRow[0]->escaped() : $infoRow[0];
 102                                 $value = ( $infoRow[1] instanceof Message ) ? $infoRow[1]->escaped() : $infoRow[1];
 103                                 $table = $this->addRow( $table, $name, $value );
 104                         }
 105                         $content = $this->addTable( $content, $table );
 106                 }
 107
 108                 // Page footer
 109                 if ( !$this->msg( 'pageinfo-footer' )->isDisabled() ) {
 110                         $content .= $this->msg( 'pageinfo-footer' )->parse();
 111                 }
 112
 113                 // Page credits
 114                 /*if ( $this->page->exists() ) {
 115                         $content .= Html::rawElement( 'div', array( 'id' => 'mw-credits' ), $this->getContributors() );
 116                 }*/
 117
 118                 return $content;
 119         }
 120
 121         /**
 122          * Creates a header that can be added to the output.
 123          *
 124          * @param $header The header text.
 125          * @return string The HTML.
 126          */
 127         protected function makeHeader( $header ) {
 128                 global $wgParser;
 129                 $spanAttribs = array( 'class' => 'mw-headline', 'id' => $wgParser->guessSectionNameFromWikiText( $header ) );
 130                 return Html::rawElement( 'h2', array(), Html::element( 'span', $spanAttribs, $header ) );
 131         }
 132
 133         /**
 134          * Adds a row to a table that will be added to the content.
 135          *
 136          * @param $table string The table that will be added to the content
 137          * @param $name string The name of the row
 138          * @param $value string The value of the row
 139          * @return string The table with the row added
 140          */
 141         protected function addRow( $table, $name, $value ) {
 142                 return $table . Html::rawElement( 'tr', array(),
 143                         Html::rawElement( 'td', array( 'style' => 'vertical-align: top;' ), $name ) .
 144                         Html::rawElement( 'td', array(), $value )
 145                 );
 146         }
 147
 148         /**
 149          * Adds a table to the content that will be added to the output.
 150          *
 151          * @param $content string The content that will be added to the output
 152          * @param $table string The table
 153          * @return string The content with the table added
 154          */
 155         protected function addTable( $content, $table ) {
 156                 return $content . Html::rawElement( 'table', array( 'class' => 'wikitable mw-page-info' ),
 157                         $table );
 158         }
 159
 160         /**
 161          * Returns page information in an easily-manipulated format. Array keys are used so extensions
 162          * may add additional information in arbitrary positions. Array values are arrays with one
 163          * element to be rendered as a header, arrays with two elements to be rendered as a table row.
 164          *
 165          * @return array
 166          */
 167         protected function pageInfo() {
 168                 global $wgContLang, $wgRCMaxAge, $wgMemc, $wgUnwatchedPageThreshold;
 169
 170                 $user = $this->getUser();
 171                 $lang = $this->getLanguage();
 172                 $title = $this->getTitle();
 173                 $id = $title->getArticleID();
 174
 175                 $memcKey = wfMemcKey( 'infoaction', $title->getPrefixedText(), $this->page->getRevision()->getId() );
 176                 $pageCounts = $wgMemc->get( $memcKey );
 177                 if ( $pageCounts === false ) {
 178                         // Get page information that would be too "expensive" to retrieve by normal means
 179                         $pageCounts = self::pageCounts( $title );
 180
 181                         $wgMemc->set( $memcKey, $pageCounts );
 182                 }
 183
 184                 // Get page properties
 185                 $dbr = wfGetDB( DB_SLAVE );
 186                 $result = $dbr->select(
 187                         'page_props',
 188                         array( 'pp_propname', 'pp_value' ),
 189                         array( 'pp_page' => $id ),
 190                         __METHOD__
 191                 );
 192
 193                 $pageProperties = array();
 194                 foreach ( $result as $row ) {
 195                         $pageProperties[$row->pp_propname] = $row->pp_value;
 196                 }
 197
 198                 // Basic information
 199                 $pageInfo = array();
 200                 $pageInfo['header-basic'] = array();
 201
 202                 // Display title
 203                 $displayTitle = $title->getPrefixedText();
 204                 if ( !empty( $pageProperties['displaytitle'] ) ) {
 205                         $displayTitle = $pageProperties['displaytitle'];
 206                 }
 207
 208                 $pageInfo['header-basic'][] = array(
 209                         $this->msg( 'pageinfo-display-title' ), $displayTitle
 210                 );
 211
 212                 // Is it a redirect? If so, where to?
 213                 if ( $title->isRedirect() ) {
 214                         $pageInfo['header-basic'][] = array(
 215                                 $this->msg( 'pageinfo-redirectsto' ),
 216                                 Linker::link( $this->page->getRedirectTarget() ) .
 217                                 $this->msg( 'word-separator' )->text() .
 218                                 $this->msg( 'parentheses', Linker::link(
 219                                         $this->page->getRedirectTarget(),
 220                                         $this->msg( 'pageinfo-redirectsto-info' )->escaped(),
 221                                         array(),
 222                                         array( 'action' => 'info' )
 223                                 ) )->text()
 224                         );
 225                 }
 226
 227                 // Default sort key
 228                 $sortKey = $title->getCategorySortKey();
 229                 if ( !empty( $pageProperties['defaultsort'] ) ) {
 230                         $sortKey = $pageProperties['defaultsort'];
 231                 }
 232
 233                 $pageInfo['header-basic'][] = array( $this->msg( 'pageinfo-default-sort' ), $sortKey );
 234
 235                 // Page length (in bytes)
 236                 $pageInfo['header-basic'][] = array(
 237                         $this->msg( 'pageinfo-length' ), $lang->formatNum( $title->getLength() )
 238                 );
 239
 240                 // Page ID (number not localised, as it's a database ID)
 241                 $pageInfo['header-basic'][] = array( $this->msg( 'pageinfo-article-id' ), $id );
 242
 243                 // Language in which the page content is (supposed to be) written
 244                 $pageLang = $title->getPageLanguage()->getCode();
 245                 $pageInfo['header-basic'][] = array( $this->msg( 'pageinfo-language' ),
 246                         Language::fetchLanguageName( $pageLang, $lang->getCode() )
 247                         . ' ' . $this->msg( 'parentheses', $pageLang ) );
 248
 249                 // Search engine status
 250                 $pOutput = new ParserOutput();
 251                 if ( isset( $pageProperties['noindex'] ) ) {
 252                         $pOutput->setIndexPolicy( 'noindex' );
 253                 }
 254
 255                 // Use robot policy logic
 256                 $policy = $this->page->getRobotPolicy( 'view', $pOutput );
 257                 $pageInfo['header-basic'][] = array(
 258                         $this->msg( 'pageinfo-robot-policy' ), $this->msg( "pageinfo-robot-${policy['index']}" )
 259                 );
 260
 261                 if ( isset( $pageCounts['views'] ) ) {
 262                         // Number of views
 263                         $pageInfo['header-basic'][] = array(
 264                                 $this->msg( 'pageinfo-views' ), $lang->formatNum( $pageCounts['views'] )
 265                         );
 266                 }
 267
 268                 if (
 269                         $user->isAllowed( 'unwatchedpages' ) ||
 270                         ( $wgUnwatchedPageThreshold !== false &&
 271                           $pageCounts['watchers'] >= $wgUnwatchedPageThreshold )
 272                 ) {
 273                         // Number of page watchers
 274                         $pageInfo['header-basic'][] = array(
 275                                 $this->msg( 'pageinfo-watchers' ), $lang->formatNum( $pageCounts['watchers'] )
 276                         );
 277                 }
 278
 279                 // Redirects to this page
 280                 $whatLinksHere = SpecialPage::getTitleFor( 'Whatlinkshere', $title->getPrefixedText() );
 281                 $pageInfo['header-basic'][] = array(
 282                         Linker::link(
 283                                 $whatLinksHere,
 284                                 $this->msg( 'pageinfo-redirects-name' )->escaped(),
 285                                 array(),
 286                                 array( 'hidelinks' => 1, 'hidetrans' => 1 )
 287                         ),
 288                         $this->msg( 'pageinfo-redirects-value' )
 289                                 ->numParams( count( $title->getRedirectsHere() ) )
 290                 );
 291
 292                 // Is it counted as a content page?
 293                 if ( $this->page->isCountable() ) {
 294                         $pageInfo['header-basic'][] = array(
 295                                 $this->msg( 'pageinfo-contentpage' ),
 296                                 $this->msg( 'pageinfo-contentpage-yes' )
 297                         );
 298                 }
 299
 300                 // Subpages of this page, if subpages are enabled for the current NS
 301                 if ( MWNamespace::hasSubpages( $title->getNamespace() ) ) {
 302                         $prefixIndex = SpecialPage::getTitleFor( 'Prefixindex', $title->getPrefixedText() . '/' );
 303                         $pageInfo['header-basic'][] = array(
 304                                 Linker::link( $prefixIndex, $this->msg( 'pageinfo-subpages-name' )->escaped() ),
 305                                 $this->msg( 'pageinfo-subpages-value' )
 306                                         ->numParams(
 307                                                 $pageCounts['subpages']['total'],
 308                                                 $pageCounts['subpages']['redirects'],
 309                                                 $pageCounts['subpages']['nonredirects'] )
 310                         );
 311                 }
 312
 313                 // Page protection
 314                 $pageInfo['header-restrictions'] = array();
 315
 316                 // Is this page effected by the cascading protection of something which includes it?
 317                 if ( $title->isCascadeProtected() ) {
 318                         $cascadingFrom = '';
 319                         $sources = $title->getCascadeProtectionSources(); // Array deferencing is in PHP 5.4 :(
 320
 321                         foreach ( $sources[0] as $sourceTitle ) {
 322                                 $cascadingFrom .= Html::rawElement( 'li', array(), Linker::linkKnown( $sourceTitle ) );
 323                         }
 324
 325                         $cascadingFrom = Html::rawElement( 'ul', array(), $cascadingFrom );
 326                         $pageInfo['header-restrictions'][] = array(
 327                                 $this->msg( 'pageinfo-protect-cascading-from' ),
 328                                 $cascadingFrom
 329                         );
 330                 }
 331
 332                 // Is out protection set to cascade to other pages?
 333                 if ( $title->areRestrictionsCascading() ) {
 334                         $pageInfo['header-restrictions'][] = array(
 335                                 $this->msg( 'pageinfo-protect-cascading' ),
 336                                 $this->msg( 'pageinfo-protect-cascading-yes' )
 337                         );
 338                 }
 339
 340                 // Page protection
 341                 foreach ( $title->getRestrictionTypes() as $restrictionType ) {
 342                         $protectionLevel = implode( ', ', $title->getRestrictions( $restrictionType ) );
 343
 344                         if ( $protectionLevel == '' ) {
 345                                 // Allow all users
 346                                 $message = $this->msg( 'protect-default' )->escaped();
 347                         } else {
 348                                 // Administrators only
 349                                 $message = $this->msg( "protect-level-$protectionLevel" );
 350                                 if ( $message->isDisabled() ) {
 351                                         // Require "$1" permission
 352                                         $message = $this->msg( "protect-fallback", $protectionLevel )->parse();
 353                                 } else {
 354                                         $message = $message->escaped();
 355                                 }
 356                         }
 357
 358                         $pageInfo['header-restrictions'][] = array(
 359                                 $this->msg( "restriction-$restrictionType" ), $message
 360                         );
 361                 }
 362
 363                 if ( !$this->page->exists() ) {
 364                         return $pageInfo;
 365                 }
 366
 367                 // Edit history
 368                 $pageInfo['header-edits'] = array();
 369
 370                 $firstRev = $this->page->getOldestRevision();
 371
 372                 // Page creator
 373                 $pageInfo['header-edits'][] = array(
 374                         $this->msg( 'pageinfo-firstuser' ),
 375                         Linker::revUserTools( $firstRev )
 376                 );
 377
 378                 // Date of page creation
 379                 $pageInfo['header-edits'][] = array(
 380                         $this->msg( 'pageinfo-firsttime' ),
 381                         Linker::linkKnown(
 382                                 $title,
 383                                 $lang->userTimeAndDate( $firstRev->getTimestamp(), $user ),
 384                                 array(),
 385                                 array( 'oldid' => $firstRev->getId() )
 386                         )
 387                 );
 388
 389                 // Latest editor
 390                 $pageInfo['header-edits'][] = array(
 391                         $this->msg( 'pageinfo-lastuser' ),
 392                         Linker::revUserTools( $this->page->getRevision() )
 393                 );
 394
 395                 // Date of latest edit
 396                 $pageInfo['header-edits'][] = array(
 397                         $this->msg( 'pageinfo-lasttime' ),
 398                         Linker::linkKnown(
 399                                 $title,
 400                                 $lang->userTimeAndDate( $this->page->getTimestamp(), $user ),
 401                                 array(),
 402                                 array( 'oldid' => $this->page->getLatest() )
 403                         )
 404                 );
 405
 406                 // Total number of edits
 407                 $pageInfo['header-edits'][] = array(
 408                         $this->msg( 'pageinfo-edits' ), $lang->formatNum( $pageCounts['edits'] )
 409                 );
 410
 411                 // Total number of distinct authors
 412                 $pageInfo['header-edits'][] = array(
 413                         $this->msg( 'pageinfo-authors' ), $lang->formatNum( $pageCounts['authors'] )
 414                 );
 415
 416                 // Recent number of edits (within past 30 days)
 417                 $pageInfo['header-edits'][] = array(
 418                         $this->msg( 'pageinfo-recent-edits', $lang->formatDuration( $wgRCMaxAge ) ),
 419                         $lang->formatNum( $pageCounts['recent_edits'] )
 420                 );
 421
 422                 // Recent number of distinct authors
 423                 $pageInfo['header-edits'][] = array(
 424                         $this->msg( 'pageinfo-recent-authors' ), $lang->formatNum( $pageCounts['recent_authors'] )
 425                 );
 426
 427                 // Array of MagicWord objects
 428                 $magicWords = MagicWord::getDoubleUnderscoreArray();
 429
 430                 // Array of magic word IDs
 431                 $wordIDs = $magicWords->names;
 432
 433                 // Array of IDs => localized magic words
 434                 $localizedWords = $wgContLang->getMagicWords();
 435
 436                 $listItems = array();
 437                 foreach ( $pageProperties as $property => $value ) {
 438                         if ( in_array( $property, $wordIDs ) ) {
 439                                 $listItems[] = Html::element( 'li', array(), $localizedWords[$property][1] );
 440                         }
 441                 }
 442
 443                 $localizedList = Html::rawElement( 'ul', array(), implode( '', $listItems ) );
 444                 $hiddenCategories = $this->page->getHiddenCategories();
 445                 $transcludedTemplates = $title->getTemplateLinksFrom();
 446
 447                 if ( count( $listItems ) > 0
 448                         || count( $hiddenCategories ) > 0
 449                         || count( $transcludedTemplates ) > 0 ) {
 450                         // Page properties
 451                         $pageInfo['header-properties'] = array();
 452
 453                         // Magic words
 454                         if ( count( $listItems ) > 0 ) {
 455                                 $pageInfo['header-properties'][] = array(
 456                                         $this->msg( 'pageinfo-magic-words' )->numParams( count( $listItems ) ),
 457                                         $localizedList
 458                                 );
 459                         }
 460
 461                         // Hidden categories
 462                         if ( count( $hiddenCategories ) > 0 ) {
 463                                 $pageInfo['header-properties'][] = array(
 464                                         $this->msg( 'pageinfo-hidden-categories' )
 465                                                 ->numParams( count( $hiddenCategories ) ),
 466                                         Linker::formatHiddenCategories( $hiddenCategories )
 467                                 );
 468                         }
 469
 470                         // Transcluded templates
 471                         if ( count( $transcludedTemplates ) > 0 ) {
 472                                 $pageInfo['header-properties'][] = array(
 473                                         $this->msg( 'pageinfo-templates' )
 474                                                 ->numParams( count( $transcludedTemplates ) ),
 475                                         Linker::formatTemplates( $transcludedTemplates )
 476                                 );
 477                         }
 478                 }
 479
 480                 return $pageInfo;
 481         }
 482
 483         /**
 484          * Returns page counts that would be too "expensive" to retrieve by normal means.
 485          *
 486          * @param Title $title Title to get counts for
 487          * @return array
 488          */
 489         protected static function pageCounts( Title $title ) {
 490                 global $wgRCMaxAge, $wgDisableCounters;
 491
 492                 wfProfileIn( __METHOD__ );
 493                 $id = $title->getArticleID();
 494
 495                 $dbr = wfGetDB( DB_SLAVE );
 496                 $result = array();
 497
 498                 if ( !$wgDisableCounters ) {
 499                         // Number of views
 500                         $views = (int) $dbr->selectField(
 501                                 'page',
 502                                 'page_counter',
 503                                 array( 'page_id' => $id ),
 504                                 __METHOD__
 505                         );
 506                         $result['views'] = $views;
 507                 }
 508
 509                 // Number of page watchers
 510                 $watchers = (int) $dbr->selectField(
 511                         'watchlist',
 512                         'COUNT(*)',
 513                         array(
 514                                 'wl_namespace' => $title->getNamespace(),
 515                                 'wl_title'     => $title->getDBkey(),
 516                         ),
 517                         __METHOD__
 518                 );
 519                 $result['watchers'] = $watchers;
 520
 521                 // Total number of edits
 522                 $edits = (int) $dbr->selectField(
 523                         'revision',
 524                         'COUNT(rev_page)',
 525                         array( 'rev_page' => $id ),
 526                         __METHOD__
 527                 );
 528                 $result['edits'] = $edits;
 529
 530                 // Total number of distinct authors
 531                 $authors = (int) $dbr->selectField(
 532                         'revision',
 533                         'COUNT(DISTINCT rev_user_text)',
 534                         array( 'rev_page' => $id ),
 535                         __METHOD__
 536                 );
 537                 $result['authors'] = $authors;
 538
 539                 // "Recent" threshold defined by $wgRCMaxAge
 540                 $threshold = $dbr->timestamp( time() - $wgRCMaxAge );
 541
 542                 // Recent number of edits
 543                 $edits = (int) $dbr->selectField(
 544                         'revision',
 545                         'COUNT(rev_page)',
 546                         array(
 547                                 'rev_page' => $id ,
 548                                 "rev_timestamp >= $threshold"
 549                         ),
 550                         __METHOD__
 551                 );
 552                 $result['recent_edits'] = $edits;
 553
 554                 // Recent number of distinct authors
 555                 $authors = (int) $dbr->selectField(
 556                         'revision',
 557                         'COUNT(DISTINCT rev_user_text)',
 558                         array(
 559                                 'rev_page' => $id,
 560                                 "rev_timestamp >= $threshold"
 561                         ),
 562                         __METHOD__
 563                 );
 564                 $result['recent_authors'] = $authors;
 565
 566                 // Subpages (if enabled)
 567                 if ( MWNamespace::hasSubpages( $title->getNamespace() ) ) {
 568                         $conds = array( 'page_namespace' => $title->getNamespace() );
 569                         $conds[] = 'page_title ' . $dbr->buildLike( $title->getDBkey() . '/', $dbr->anyString() );
 570
 571                         // Subpages of this page (redirects)
 572                         $conds['page_is_redirect'] = 1;
 573                         $result['subpages']['redirects'] = (int) $dbr->selectField(
 574                                 'page',
 575                                 'COUNT(page_id)',
 576                                 $conds,
 577                                 __METHOD__ );
 578
 579                         // Subpages of this page (non-redirects)
 580                         $conds['page_is_redirect'] = 0;
 581                         $result['subpages']['nonredirects'] = (int) $dbr->selectField(
 582                                 'page',
 583                                 'COUNT(page_id)',
 584                                 $conds,
 585                                 __METHOD__
 586                         );
 587
 588                         // Subpages of this page (total)
 589                         $result['subpages']['total'] = $result['subpages']['redirects']
 590                                 + $result['subpages']['nonredirects'];
 591                 }
 592
 593                 wfProfileOut( __METHOD__ );
 594                 return $result;
 595         }
 596
 597         /**
 598          * Returns the name that goes in the "<h1>" page title.
 599          *
 600          * @return string
 601          */
 602         protected function getPageTitle() {
 603                 return $this->msg( 'pageinfo-title', $this->getTitle()->getPrefixedText() )->text();
 604         }
 605
 606         /**
 607          * Get a list of contributors of $article
 608          * @return string: html
 609          */
 610         protected function getContributors() {
 611                 global $wgHiddenPrefs;
 612
 613                 $contributors = $this->page->getContributors();
 614                 $real_names = array();
 615                 $user_names = array();
 616                 $anon_ips = array();
 617
 618                 # Sift for real versus user names
 619                 foreach ( $contributors as $user ) {
 620                         $page = $user->isAnon()
 621                                 ? SpecialPage::getTitleFor( 'Contributions', $user->getName() )
 622                                 : $user->getUserPage();
 623
 624                         if ( $user->getID() == 0 ) {
 625                                 $anon_ips[] = Linker::link( $page, htmlspecialchars( $user->getName() ) );
 626                         } elseif ( !in_array( 'realname', $wgHiddenPrefs ) && $user->getRealName() ) {
 627                                 $real_names[] = Linker::link( $page, htmlspecialchars( $user->getRealName() ) );
 628                         } else {
 629                                 $user_names[] = Linker::link( $page, htmlspecialchars( $user->getName() ) );
 630                         }
 631                 }
 632
 633                 $lang = $this->getLanguage();
 634
 635                 $real = $lang->listToText( $real_names );
 636
 637                 # "ThisSite user(s) A, B and C"
 638                 if ( count( $user_names ) ) {
 639                         $user = $this->msg( 'siteusers' )->rawParams( $lang->listToText( $user_names ) )->params(
 640                                 count( $user_names ) )->escaped();
 641                 } else {
 642                         $user = false;
 643                 }
 644
 645                 if ( count( $anon_ips ) ) {
 646                         $anon = $this->msg( 'anonusers' )->rawParams( $lang->listToText( $anon_ips ) )->params(
 647                                 count( $anon_ips ) )->escaped();
 648                 } else {
 649                         $anon = false;
 650                 }
 651
 652                 # This is the big list, all mooshed together. We sift for blank strings
 653                 $fulllist = array();
 654                 foreach ( array( $real, $user, $anon ) as $s ) {
 655                         if ( $s !== '' ) {
 656                                 array_push( $fulllist, $s );
 657                         }
 658                 }
 659
 660                 $count = count( $fulllist );
 661                 # "Based on work by ..."
 662                 return $count
 663                         ? $this->msg( 'othercontribs' )->rawParams(
 664                                 $lang->listToText( $fulllist ) )->params( $count )->escaped()
 665                         : '';
 666         }
 667
 668         /**
 669          * Returns the description that goes below the "<h1>" tag.
 670          *
 671          * @return string
 672          */
 673         protected function getDescription() {
 674                 return '';
 675         }
 676 }