includes/specialpage/SpecialPageFactory.php

   1 <?php
   2 /**
   3  * Factory for handling the special page list and generating SpecialPage objects.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup SpecialPage
  22  * @defgroup SpecialPage SpecialPage
  23  */
  24
  25 /**
  26  * Factory for handling the special page list and generating SpecialPage objects.
  27  *
  28  * To add a special page in an extension, add to $wgSpecialPages either
  29  * an object instance or an array containing the name and constructor
  30  * parameters. The latter is preferred for performance reasons.
  31  *
  32  * The object instantiated must be either an instance of SpecialPage or a
  33  * sub-class thereof. It must have an execute() method, which sends the HTML
  34  * for the special page to $wgOut. The parent class has an execute() method
  35  * which distributes the call to the historical global functions. Additionally,
  36  * execute() also checks if the user has the necessary access privileges
  37  * and bails out if not.
  38  *
  39  * To add a core special page, use the similar static list in
  40  * SpecialPageFactory::$list. To remove a core static special page at runtime, use
  41  * a SpecialPage_initList hook.
  42  *
  43  * @ingroup SpecialPage
  44  * @since 1.17
  45  */
  46 class SpecialPageFactory {
  47         /**
  48          * List of special page names to the subclass of SpecialPage which handles them.
  49          */
  50         private static $coreList = array(
  51                 // Maintenance Reports
  52                 'BrokenRedirects' => 'BrokenRedirectsPage',
  53                 'Deadendpages' => 'DeadendPagesPage',
  54                 'DoubleRedirects' => 'DoubleRedirectsPage',
  55                 'Longpages' => 'LongPagesPage',
  56                 'Ancientpages' => 'AncientPagesPage',
  57                 'Lonelypages' => 'LonelyPagesPage',
  58                 'Fewestrevisions' => 'FewestrevisionsPage',
  59                 'Withoutinterwiki' => 'WithoutInterwikiPage',
  60                 'Protectedpages' => 'SpecialProtectedpages',
  61                 'Protectedtitles' => 'SpecialProtectedtitles',
  62                 'Shortpages' => 'ShortPagesPage',
  63                 'Uncategorizedcategories' => 'UncategorizedCategoriesPage',
  64                 'Uncategorizedimages' => 'UncategorizedImagesPage',
  65                 'Uncategorizedpages' => 'UncategorizedPagesPage',
  66                 'Uncategorizedtemplates' => 'UncategorizedTemplatesPage',
  67                 'Unusedcategories' => 'UnusedCategoriesPage',
  68                 'Unusedimages' => 'UnusedimagesPage',
  69                 'Unusedtemplates' => 'UnusedtemplatesPage',
  70                 'Unwatchedpages' => 'UnwatchedpagesPage',
  71                 'Wantedcategories' => 'WantedCategoriesPage',
  72                 'Wantedfiles' => 'WantedFilesPage',
  73                 'Wantedpages' => 'WantedPagesPage',
  74                 'Wantedtemplates' => 'WantedTemplatesPage',
  75
  76                 // List of pages
  77                 'Allpages' => 'SpecialAllPages',
  78                 'Prefixindex' => 'SpecialPrefixindex',
  79                 'Categories' => 'SpecialCategories',
  80                 'Listredirects' => 'ListredirectsPage',
  81                 'PagesWithProp' => 'SpecialPagesWithProp',
  82                 'TrackingCategories' => 'SpecialTrackingCategories',
  83
  84                 // Login/create account
  85                 'Userlogin' => 'LoginForm',
  86                 'CreateAccount' => 'SpecialCreateAccount',
  87
  88                 // Users and rights
  89                 'Block' => 'SpecialBlock',
  90                 'Unblock' => 'SpecialUnblock',
  91                 'BlockList' => 'SpecialBlockList',
  92                 'ChangePassword' => 'SpecialChangePassword',
  93                 'PasswordReset' => 'SpecialPasswordReset',
  94                 'DeletedContributions' => 'DeletedContributionsPage',
  95                 'Preferences' => 'SpecialPreferences',
  96                 'ResetTokens' => 'SpecialResetTokens',
  97                 'Contributions' => 'SpecialContributions',
  98                 'Listgrouprights' => 'SpecialListGroupRights',
  99                 'Listusers' => 'SpecialListUsers',
 100                 'Listadmins' => 'SpecialListAdmins',
 101                 'Listbots' => 'SpecialListBots',
 102                 'Userrights' => 'UserrightsPage',
 103                 'EditWatchlist' => 'SpecialEditWatchlist',
 104
 105                 // Recent changes and logs
 106                 'Newimages' => 'SpecialNewFiles',
 107                 'Log' => 'SpecialLog',
 108                 'Watchlist' => 'SpecialWatchlist',
 109                 'Newpages' => 'SpecialNewpages',
 110                 'Recentchanges' => 'SpecialRecentChanges',
 111                 'Recentchangeslinked' => 'SpecialRecentChangesLinked',
 112                 'Tags' => 'SpecialTags',
 113
 114                 // Media reports and uploads
 115                 'Listfiles' => 'SpecialListFiles',
 116                 'Filepath' => 'SpecialFilepath',
 117                 'MediaStatistics' => 'MediaStatisticsPage',
 118                 'MIMEsearch' => 'MIMEsearchPage',
 119                 'FileDuplicateSearch' => 'FileDuplicateSearchPage',
 120                 'Upload' => 'SpecialUpload',
 121                 'UploadStash' => 'SpecialUploadStash',
 122                 'ListDuplicatedFiles' => 'ListDuplicatedFilesPage',
 123
 124                 // Data and tools
 125                 'Statistics' => 'SpecialStatistics',
 126                 'Allmessages' => 'SpecialAllMessages',
 127                 'Version' => 'SpecialVersion',
 128                 'Lockdb' => 'SpecialLockdb',
 129                 'Unlockdb' => 'SpecialUnlockdb',
 130
 131                 // Redirecting special pages
 132                 'LinkSearch' => 'LinkSearchPage',
 133                 'Randompage' => 'RandomPage',
 134                 'RandomInCategory' => 'SpecialRandomInCategory',
 135                 'Randomredirect' => 'SpecialRandomredirect',
 136
 137                 // High use pages
 138                 'Mostlinkedcategories' => 'MostlinkedCategoriesPage',
 139                 'Mostimages' => 'MostimagesPage',
 140                 'Mostinterwikis' => 'MostinterwikisPage',
 141                 'Mostlinked' => 'MostlinkedPage',
 142                 'Mostlinkedtemplates' => 'MostlinkedTemplatesPage',
 143                 'Mostcategories' => 'MostcategoriesPage',
 144                 'Mostrevisions' => 'MostrevisionsPage',
 145
 146                 // Page tools
 147                 'ComparePages' => 'SpecialComparePages',
 148                 'Export' => 'SpecialExport',
 149                 'Import' => 'SpecialImport',
 150                 'Undelete' => 'SpecialUndelete',
 151                 'Whatlinkshere' => 'SpecialWhatLinksHere',
 152                 'MergeHistory' => 'SpecialMergeHistory',
 153                 'ExpandTemplates' => 'SpecialExpandTemplates',
 154
 155                 // Other
 156                 'Booksources' => 'SpecialBookSources',
 157
 158                 // Unlisted / redirects
 159                 'ApiHelp' => 'SpecialApiHelp',
 160                 'Blankpage' => 'SpecialBlankpage',
 161                 'Diff' => 'SpecialDiff',
 162                 'EditTags' => 'SpecialEditTags',
 163                 'Emailuser' => 'SpecialEmailUser',
 164                 'Movepage' => 'MovePageForm',
 165                 'Mycontributions' => 'SpecialMycontributions',
 166                 'MyLanguage' => 'SpecialMyLanguage',
 167                 'Mypage' => 'SpecialMypage',
 168                 'Mytalk' => 'SpecialMytalk',
 169                 'Myuploads' => 'SpecialMyuploads',
 170                 'AllMyUploads' => 'SpecialAllMyUploads',
 171                 'PermanentLink' => 'SpecialPermanentLink',
 172                 'Redirect' => 'SpecialRedirect',
 173                 'Revisiondelete' => 'SpecialRevisionDelete',
 174                 'RunJobs' => 'SpecialRunJobs',
 175                 'Specialpages' => 'SpecialSpecialpages',
 176                 'Userlogout' => 'SpecialUserlogout',
 177         );
 178
 179         private static $list;
 180         private static $aliases;
 181
 182         /**
 183          * Reset the internal list of special pages. Useful when changing $wgSpecialPages after
 184          * the internal list has already been initialized, e.g. during testing.
 185          */
 186         public static function resetList() {
 187                 self::$list = null;
 188                 self::$aliases = null;
 189         }
 190
 191         /**
 192          * Returns a list of canonical special page names.
 193          * May be used to iterate over all registered special pages.
 194          *
 195          * @return string[]
 196          */
 197         public static function getNames() {
 198                 return array_keys( self::getPageList() );
 199         }
 200
 201         /**
 202          * Get the special page list as an array
 203          *
 204          * @deprecated since 1.24, use getNames() instead.
 205          * @return array
 206          */
 207         public static function getList() {
 208                 wfDeprecated( __FUNCTION__, '1.24' );
 209                 return self::getPageList();
 210         }
 211
 212         /**
 213          * Get the special page list as an array
 214          *
 215          * @return array
 216          */
 217         private static function getPageList() {
 218                 global $wgSpecialPages;
 219                 global $wgDisableInternalSearch, $wgEmailAuthentication;
 220                 global $wgEnableEmail, $wgEnableJavaScriptTest;
 221                 global $wgPageLanguageUseDB, $wgContentHandlerUseDB;
 222
 223                 if ( !is_array( self::$list ) ) {
 224
 225                         self::$list = self::$coreList;
 226
 227                         if ( !$wgDisableInternalSearch ) {
 228                                 self::$list['Search'] = 'SpecialSearch';
 229                         }
 230
 231                         if ( $wgEmailAuthentication ) {
 232                                 self::$list['Confirmemail'] = 'EmailConfirmation';
 233                                 self::$list['Invalidateemail'] = 'EmailInvalidation';
 234                         }
 235
 236                         if ( $wgEnableEmail ) {
 237                                 self::$list['ChangeEmail'] = 'SpecialChangeEmail';
 238                         }
 239
 240                         if ( $wgEnableJavaScriptTest ) {
 241                                 self::$list['JavaScriptTest'] = 'SpecialJavaScriptTest';
 242                         }
 243
 244                         if ( $wgPageLanguageUseDB ) {
 245                                 self::$list['PageLanguage'] = 'SpecialPageLanguage';
 246                         }
 247                         if ( $wgContentHandlerUseDB ) {
 248                                 self::$list['ChangeContentModel'] = 'SpecialChangeContentModel';
 249                         }
 250
 251                         self::$list['Activeusers'] = 'SpecialActiveUsers';
 252
 253                         // Add extension special pages
 254                         self::$list = array_merge( self::$list, $wgSpecialPages );
 255
 256                         // This hook can be used to disable unwanted core special pages
 257                         // or conditionally register special pages.
 258                         Hooks::run( 'SpecialPage_initList', array( &self::$list ) );
 259
 260                 }
 261
 262                 return self::$list;
 263         }
 264
 265         /**
 266          * Initialise and return the list of special page aliases. Returns an array where
 267          * the key is an alias, and the value is the canonical name of the special page.
 268          * All registered special pages are guaranteed to map to themselves.
 269          * @return array
 270          */
 271         private static function getAliasList() {
 272                 if ( is_null( self::$aliases ) ) {
 273                         global $wgContLang;
 274                         $aliases = $wgContLang->getSpecialPageAliases();
 275                         $pageList = self::getPageList();
 276
 277                         self::$aliases = array();
 278                         $keepAlias = array();
 279
 280                         // Force every canonical name to be an alias for itself.
 281                         foreach ( $pageList as $name => $stuff ) {
 282                                 $caseFoldedAlias = $wgContLang->caseFold( $name );
 283                                 self::$aliases[$caseFoldedAlias] = $name;
 284                                 $keepAlias[$caseFoldedAlias] = 'canonical';
 285                         }
 286
 287                         // Check for $aliases being an array since Language::getSpecialPageAliases can return null
 288                         if ( is_array( $aliases ) ) {
 289                                 foreach ( $aliases as $realName => $aliasList ) {
 290                                         $aliasList = array_values( $aliasList );
 291                                         foreach ( $aliasList as $i => $alias ) {
 292                                                 $caseFoldedAlias = $wgContLang->caseFold( $alias );
 293
 294                                                 if ( isset( self::$aliases[$caseFoldedAlias] ) &&
 295                                                         $realName === self::$aliases[$caseFoldedAlias]
 296                                                 ) {
 297                                                         // Ignore same-realName conflicts
 298                                                         continue;
 299                                                 }
 300
 301                                                 if ( !isset( $keepAlias[$caseFoldedAlias] ) ) {
 302                                                         self::$aliases[$caseFoldedAlias] = $realName;
 303                                                         if ( !$i ) {
 304                                                                 $keepAlias[$caseFoldedAlias] = 'first';
 305                                                         }
 306                                                 } elseif ( !$i ) {
 307                                                         wfWarn( "First alias '$alias' for $realName conflicts with " .
 308                                                                 "{$keepAlias[$caseFoldedAlias]} alias for " .
 309                                                                 self::$aliases[$caseFoldedAlias]
 310                                                         );
 311                                                 }
 312                                         }
 313                                 }
 314                         }
 315                 }
 316
 317                 return self::$aliases;
 318         }
 319
 320         /**
 321          * Given a special page name with a possible subpage, return an array
 322          * where the first element is the special page name and the second is the
 323          * subpage.
 324          *
 325          * @param string $alias
 326          * @return array Array( String, String|null ), or array( null, null ) if the page is invalid
 327          */
 328         public static function resolveAlias( $alias ) {
 329                 global $wgContLang;
 330                 $bits = explode( '/', $alias, 2 );
 331
 332                 $caseFoldedAlias = $wgContLang->caseFold( $bits[0] );
 333                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 334                 $aliases = self::getAliasList();
 335                 if ( isset( $aliases[$caseFoldedAlias] ) ) {
 336                         $name = $aliases[$caseFoldedAlias];
 337                 } else {
 338                         return array( null, null );
 339                 }
 340
 341                 if ( !isset( $bits[1] ) ) { // bug 2087
 342                         $par = null;
 343                 } else {
 344                         $par = $bits[1];
 345                 }
 346
 347                 return array( $name, $par );
 348         }
 349
 350         /**
 351          * Check if a given name exist as a special page or as a special page alias
 352          *
 353          * @param string $name Name of a special page
 354          * @return bool True if a special page exists with this name
 355          */
 356         public static function exists( $name ) {
 357                 list( $title, /*...*/ ) = self::resolveAlias( $name );
 358
 359                 $specialPageList = self::getPageList();
 360                 return isset( $specialPageList[$title] );
 361         }
 362
 363         /**
 364          * Find the object with a given name and return it (or NULL)
 365          *
 366          * @param string $name Special page name, may be localised and/or an alias
 367          * @return SpecialPage|null SpecialPage object or null if the page doesn't exist
 368          */
 369         public static function getPage( $name ) {
 370                 list( $realName, /*...*/ ) = self::resolveAlias( $name );
 371
 372                 $specialPageList = self::getPageList();
 373
 374                 if ( isset( $specialPageList[$realName] ) ) {
 375                         $rec = $specialPageList[$realName];
 376
 377                         if ( is_callable( $rec ) ) {
 378                                 // Use callback to instantiate the special page
 379                                 $page = call_user_func( $rec );
 380                         } elseif ( is_string( $rec ) ) {
 381                                 $className = $rec;
 382                                 $page = new $className;
 383                         } elseif ( is_array( $rec ) ) {
 384                                 $className = array_shift( $rec );
 385                                 // @deprecated, officially since 1.18, unofficially since forever
 386                                 wfDeprecated( "Array syntax for \$wgSpecialPages is deprecated ($className), " .
 387                                         "define a subclass of SpecialPage instead.", '1.18' );
 388                                 $page = ObjectFactory::getObjectFromSpec( array(
 389                                         'class' => $className,
 390                                         'args' => $rec,
 391                                         'closure_expansion' => false,
 392                                 ) );
 393                         } elseif ( $rec instanceof SpecialPage ) {
 394                                 $page = $rec; // XXX: we should deep clone here
 395                         } else {
 396                                 $page = null;
 397                         }
 398
 399                         if ( $page instanceof SpecialPage ) {
 400                                 return $page;
 401                         } else {
 402                                 // It's not a classname, nor a callback, nor a legacy constructor array,
 403                                 // nor a special page object. Give up.
 404                                 wfLogWarning( "Cannot instantiate special page $realName: bad spec!" );
 405                                 return null;
 406                         }
 407
 408                 } else {
 409                         return null;
 410                 }
 411         }
 412
 413         /**
 414          * Return categorised listable special pages which are available
 415          * for the current user, and everyone.
 416          *
 417          * @param User $user User object to check permissions, $wgUser will be used
 418          *        if not provided
 419          * @return array ( string => Specialpage )
 420          */
 421         public static function getUsablePages( User $user = null ) {
 422                 $pages = array();
 423                 if ( $user === null ) {
 424                         global $wgUser;
 425                         $user = $wgUser;
 426                 }
 427                 foreach ( self::getPageList() as $name => $rec ) {
 428                         $page = self::getPage( $name );
 429                         if ( $page ) { // not null
 430                                 $page->setContext( RequestContext::getMain() );
 431                                 if ( $page->isListed()
 432                                         && ( !$page->isRestricted() || $page->userCanExecute( $user ) )
 433                                 ) {
 434                                         $pages[$name] = $page;
 435                                 }
 436                         }
 437                 }
 438
 439                 return $pages;
 440         }
 441
 442         /**
 443          * Return categorised listable special pages for all users
 444          *
 445          * @return array ( string => Specialpage )
 446          */
 447         public static function getRegularPages() {
 448                 $pages = array();
 449                 foreach ( self::getPageList() as $name => $rec ) {
 450                         $page = self::getPage( $name );
 451                         if ( $page->isListed() && !$page->isRestricted() ) {
 452                                 $pages[$name] = $page;
 453                         }
 454                 }
 455
 456                 return $pages;
 457         }
 458
 459         /**
 460          * Return categorised listable special pages which are available
 461          * for the current user, but not for everyone
 462          *
 463          * @param User|null $user User object to use or null for $wgUser
 464          * @return array ( string => Specialpage )
 465          */
 466         public static function getRestrictedPages( User $user = null ) {
 467                 $pages = array();
 468                 if ( $user === null ) {
 469                         global $wgUser;
 470                         $user = $wgUser;
 471                 }
 472                 foreach ( self::getPageList() as $name => $rec ) {
 473                         $page = self::getPage( $name );
 474                         if (
 475                                 $page->isListed()
 476                                 && $page->isRestricted()
 477                                 && $page->userCanExecute( $user )
 478                         ) {
 479                                 $pages[$name] = $page;
 480                         }
 481                 }
 482
 483                 return $pages;
 484         }
 485
 486         /**
 487          * Execute a special page path.
 488          * The path may contain parameters, e.g. Special:Name/Params
 489          * Extracts the special page name and call the execute method, passing the parameters
 490          *
 491          * Returns a title object if the page is redirected, false if there was no such special
 492          * page, and true if it was successful.
 493          *
 494          * @param Title $title
 495          * @param IContextSource $context
 496          * @param bool $including Bool output is being captured for use in {{special:whatever}}
 497          *
 498          * @return bool
 499          */
 500         public static function executePath( Title &$title, IContextSource &$context, $including = false ) {
 501
 502                 // @todo FIXME: Redirects broken due to this call
 503                 $bits = explode( '/', $title->getDBkey(), 2 );
 504                 $name = $bits[0];
 505                 if ( !isset( $bits[1] ) ) { // bug 2087
 506                         $par = null;
 507                 } else {
 508                         $par = $bits[1];
 509                 }
 510                 $page = self::getPage( $name );
 511                 // Nonexistent?
 512                 if ( !$page ) {
 513                         $context->getOutput()->setArticleRelated( false );
 514                         $context->getOutput()->setRobotPolicy( 'noindex,nofollow' );
 515
 516                         global $wgSend404Code;
 517                         if ( $wgSend404Code ) {
 518                                 $context->getOutput()->setStatusCode( 404 );
 519                         }
 520
 521                         $context->getOutput()->showErrorPage( 'nosuchspecialpage', 'nospecialpagetext' );
 522
 523                         return false;
 524                 }
 525
 526                 // Page exists, set the context
 527                 $page->setContext( $context );
 528
 529                 if ( !$including ) {
 530                         // Redirect to canonical alias for GET commands
 531                         // Not for POST, we'd lose the post data, so it's best to just distribute
 532                         // the request. Such POST requests are possible for old extensions that
 533                         // generate self-links without being aware that their default name has
 534                         // changed.
 535                         if ( $name != $page->getLocalName() && !$context->getRequest()->wasPosted() ) {
 536                                 $query = $context->getRequest()->getQueryValues();
 537                                 unset( $query['title'] );
 538                                 $title = $page->getPageTitle( $par );
 539                                 $url = $title->getFullURL( $query );
 540                                 $context->getOutput()->redirect( $url );
 541
 542                                 return $title;
 543                         } else {
 544                                 $context->setTitle( $page->getPageTitle( $par ) );
 545                         }
 546                 } elseif ( !$page->isIncludable() ) {
 547                         return false;
 548                 }
 549
 550                 $page->including( $including );
 551
 552                 // Execute special page
 553                 $page->run( $par );
 554
 555                 return true;
 556         }
 557
 558         /**
 559          * Just like executePath() but will override global variables and execute
 560          * the page in "inclusion" mode. Returns true if the execution was
 561          * successful or false if there was no such special page, or a title object
 562          * if it was a redirect.
 563          *
 564          * Also saves the current $wgTitle, $wgOut, $wgRequest, $wgUser and $wgLang
 565          * variables so that the special page will get the context it'd expect on a
 566          * normal request, and then restores them to their previous values after.
 567          *
 568          * @param Title $title
 569          * @param IContextSource $context
 570          * @return string HTML fragment
 571          */
 572         public static function capturePath( Title $title, IContextSource $context ) {
 573                 global $wgOut, $wgTitle, $wgRequest, $wgUser, $wgLang;
 574
 575                 // Save current globals
 576                 $oldTitle = $wgTitle;
 577                 $oldOut = $wgOut;
 578                 $oldRequest = $wgRequest;
 579                 $oldUser = $wgUser;
 580                 $oldLang = $wgLang;
 581
 582                 // Set the globals to the current context
 583                 $wgTitle = $title;
 584                 $wgOut = $context->getOutput();
 585                 $wgRequest = $context->getRequest();
 586                 $wgUser = $context->getUser();
 587                 $wgLang = $context->getLanguage();
 588
 589                 // The useful part
 590                 $ret = self::executePath( $title, $context, true );
 591
 592                 // And restore the old globals
 593                 $wgTitle = $oldTitle;
 594                 $wgOut = $oldOut;
 595                 $wgRequest = $oldRequest;
 596                 $wgUser = $oldUser;
 597                 $wgLang = $oldLang;
 598
 599                 return $ret;
 600         }
 601
 602         /**
 603          * Get the local name for a specified canonical name
 604          *
 605          * @param string $name
 606          * @param string|bool $subpage
 607          * @return string
 608          */
 609         public static function getLocalNameFor( $name, $subpage = false ) {
 610                 global $wgContLang;
 611                 $aliases = $wgContLang->getSpecialPageAliases();
 612                 $aliasList = self::getAliasList();
 613
 614                 // Find the first alias that maps back to $name
 615                 if ( isset( $aliases[$name] ) ) {
 616                         $found = false;
 617                         foreach ( $aliases[$name] as $alias ) {
 618                                 $caseFoldedAlias = $wgContLang->caseFold( $alias );
 619                                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 620                                 if ( isset( $aliasList[$caseFoldedAlias] ) &&
 621                                         $aliasList[$caseFoldedAlias] === $name
 622                                 ) {
 623                                         $name = $alias;
 624                                         $found = true;
 625                                         break;
 626                                 }
 627                         }
 628                         if ( !$found ) {
 629                                 wfWarn( "Did not find a usable alias for special page '$name'. " .
 630                                         "It seems all defined aliases conflict?" );
 631                         }
 632                 } else {
 633                         // Check if someone misspelled the correct casing
 634                         if ( is_array( $aliases ) ) {
 635                                 foreach ( $aliases as $n => $values ) {
 636                                         if ( strcasecmp( $name, $n ) === 0 ) {
 637                                                 wfWarn( "Found alias defined for $n when searching for " .
 638                                                         "special page aliases for $name. Case mismatch?" );
 639                                                 return self::getLocalNameFor( $n, $subpage );
 640                                         }
 641                                 }
 642                         }
 643
 644                         wfWarn( "Did not find alias for special page '$name'. " .
 645                                 "Perhaps no aliases are defined for it?" );
 646                 }
 647
 648                 if ( $subpage !== false && !is_null( $subpage ) ) {
 649                         $name = "$name/$subpage";
 650                 }
 651
 652                 return $wgContLang->ucfirst( $name );
 653         }
 654
 655         /**
 656          * Get a title for a given alias
 657          *
 658          * @param string $alias
 659          * @return Title|null Title or null if there is no such alias
 660          */
 661         public static function getTitleForAlias( $alias ) {
 662                 list( $name, $subpage ) = self::resolveAlias( $alias );
 663                 if ( $name != null ) {
 664                         return SpecialPage::getTitleFor( $name, $subpage );
 665                 } else {
 666                         return null;
 667                 }
 668         }
 669 }