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 use MediaWiki\Linker\LinkRenderer;
  25
  26 /**
  27  * Factory for handling the special page list and generating SpecialPage objects.
  28  *
  29  * To add a special page in an extension, add to $wgSpecialPages either
  30  * an object instance or an array containing the name and constructor
  31  * parameters. The latter is preferred for performance reasons.
  32  *
  33  * The object instantiated must be either an instance of SpecialPage or a
  34  * sub-class thereof. It must have an execute() method, which sends the HTML
  35  * for the special page to $wgOut. The parent class has an execute() method
  36  * which distributes the call to the historical global functions. Additionally,
  37  * execute() also checks if the user has the necessary access privileges
  38  * and bails out if not.
  39  *
  40  * To add a core special page, use the similar static list in
  41  * SpecialPageFactory::$list. To remove a core static special page at runtime, use
  42  * a SpecialPage_initList hook.
  43  *
  44  * @ingroup SpecialPage
  45  * @since 1.17
  46  */
  47 class SpecialPageFactory {
  48         /**
  49          * List of special page names to the subclass of SpecialPage which handles them.
  50          */
  51         private static $coreList = [
  52                 // Maintenance Reports
  53                 'BrokenRedirects' => 'BrokenRedirectsPage',
  54                 'Deadendpages' => 'DeadendPagesPage',
  55                 'DoubleRedirects' => 'DoubleRedirectsPage',
  56                 'Longpages' => 'LongPagesPage',
  57                 'Ancientpages' => 'AncientPagesPage',
  58                 'Lonelypages' => 'LonelyPagesPage',
  59                 'Fewestrevisions' => 'FewestrevisionsPage',
  60                 'Withoutinterwiki' => 'WithoutInterwikiPage',
  61                 'Protectedpages' => 'SpecialProtectedpages',
  62                 'Protectedtitles' => 'SpecialProtectedtitles',
  63                 'Shortpages' => 'ShortPagesPage',
  64                 'Uncategorizedcategories' => 'UncategorizedCategoriesPage',
  65                 'Uncategorizedimages' => 'UncategorizedImagesPage',
  66                 'Uncategorizedpages' => 'UncategorizedPagesPage',
  67                 'Uncategorizedtemplates' => 'UncategorizedTemplatesPage',
  68                 'Unusedcategories' => 'UnusedCategoriesPage',
  69                 'Unusedimages' => 'UnusedimagesPage',
  70                 'Unusedtemplates' => 'UnusedtemplatesPage',
  71                 'Unwatchedpages' => 'UnwatchedpagesPage',
  72                 'Wantedcategories' => 'WantedCategoriesPage',
  73                 'Wantedfiles' => 'WantedFilesPage',
  74                 'Wantedpages' => 'WantedPagesPage',
  75                 'Wantedtemplates' => 'WantedTemplatesPage',
  76
  77                 // List of pages
  78                 'Allpages' => 'SpecialAllPages',
  79                 'Prefixindex' => 'SpecialPrefixindex',
  80                 'Categories' => 'SpecialCategories',
  81                 'Listredirects' => 'ListredirectsPage',
  82                 'PagesWithProp' => 'SpecialPagesWithProp',
  83                 'TrackingCategories' => 'SpecialTrackingCategories',
  84
  85                 // Authentication
  86                 'Userlogin' => 'SpecialUserLogin',
  87                 'Userlogout' => 'SpecialUserLogout',
  88                 'CreateAccount' => 'SpecialCreateAccount',
  89                 'LinkAccounts' => 'SpecialLinkAccounts',
  90                 'UnlinkAccounts' => 'SpecialUnlinkAccounts',
  91                 'ChangeCredentials' => 'SpecialChangeCredentials',
  92                 'RemoveCredentials' => 'SpecialRemoveCredentials',
  93
  94                 // Users and rights
  95                 'Activeusers' => 'SpecialActiveUsers',
  96                 'Block' => 'SpecialBlock',
  97                 'Unblock' => 'SpecialUnblock',
  98                 'BlockList' => 'SpecialBlockList',
  99                 'ChangePassword' => 'SpecialChangePassword',
 100                 'BotPasswords' => 'SpecialBotPasswords',
 101                 'PasswordReset' => 'SpecialPasswordReset',
 102                 'DeletedContributions' => 'DeletedContributionsPage',
 103                 'Preferences' => 'SpecialPreferences',
 104                 'ResetTokens' => 'SpecialResetTokens',
 105                 'Contributions' => 'SpecialContributions',
 106                 'Listgrouprights' => 'SpecialListGroupRights',
 107                 'Listgrants' => 'SpecialListGrants',
 108                 'Listusers' => 'SpecialListUsers',
 109                 'Listadmins' => 'SpecialListAdmins',
 110                 'Listbots' => 'SpecialListBots',
 111                 'Userrights' => 'UserrightsPage',
 112                 'EditWatchlist' => 'SpecialEditWatchlist',
 113
 114                 // Recent changes and logs
 115                 'Newimages' => 'SpecialNewFiles',
 116                 'Log' => 'SpecialLog',
 117                 'Watchlist' => 'SpecialWatchlist',
 118                 'Newpages' => 'SpecialNewpages',
 119                 'Recentchanges' => 'SpecialRecentChanges',
 120                 'Recentchangeslinked' => 'SpecialRecentChangesLinked',
 121                 'Tags' => 'SpecialTags',
 122
 123                 // Media reports and uploads
 124                 'Listfiles' => 'SpecialListFiles',
 125                 'Filepath' => 'SpecialFilepath',
 126                 'MediaStatistics' => 'MediaStatisticsPage',
 127                 'MIMEsearch' => 'MIMEsearchPage',
 128                 'FileDuplicateSearch' => 'FileDuplicateSearchPage',
 129                 'Upload' => 'SpecialUpload',
 130                 'UploadStash' => 'SpecialUploadStash',
 131                 'ListDuplicatedFiles' => 'ListDuplicatedFilesPage',
 132
 133                 // Data and tools
 134                 'ApiSandbox' => 'SpecialApiSandbox',
 135                 'Statistics' => 'SpecialStatistics',
 136                 'Allmessages' => 'SpecialAllMessages',
 137                 'Version' => 'SpecialVersion',
 138                 'Lockdb' => 'SpecialLockdb',
 139                 'Unlockdb' => 'SpecialUnlockdb',
 140
 141                 // Redirecting special pages
 142                 'LinkSearch' => 'LinkSearchPage',
 143                 'Randompage' => 'RandomPage',
 144                 'RandomInCategory' => 'SpecialRandomInCategory',
 145                 'Randomredirect' => 'SpecialRandomredirect',
 146                 'Randomrootpage' => 'SpecialRandomrootpage',
 147
 148                 // High use pages
 149                 'Mostlinkedcategories' => 'MostlinkedCategoriesPage',
 150                 'Mostimages' => 'MostimagesPage',
 151                 'Mostinterwikis' => 'MostinterwikisPage',
 152                 'Mostlinked' => 'MostlinkedPage',
 153                 'Mostlinkedtemplates' => 'MostlinkedTemplatesPage',
 154                 'Mostcategories' => 'MostcategoriesPage',
 155                 'Mostrevisions' => 'MostrevisionsPage',
 156
 157                 // Page tools
 158                 'ComparePages' => 'SpecialComparePages',
 159                 'Export' => 'SpecialExport',
 160                 'Import' => 'SpecialImport',
 161                 'Undelete' => 'SpecialUndelete',
 162                 'Whatlinkshere' => 'SpecialWhatLinksHere',
 163                 'MergeHistory' => 'SpecialMergeHistory',
 164                 'ExpandTemplates' => 'SpecialExpandTemplates',
 165
 166                 // Other
 167                 'Booksources' => 'SpecialBookSources',
 168
 169                 // Unlisted / redirects
 170                 'ApiHelp' => 'SpecialApiHelp',
 171                 'Blankpage' => 'SpecialBlankpage',
 172                 'Diff' => 'SpecialDiff',
 173                 'EditTags' => 'SpecialEditTags',
 174                 'Emailuser' => 'SpecialEmailUser',
 175                 'Movepage' => 'MovePageForm',
 176                 'Mycontributions' => 'SpecialMycontributions',
 177                 'MyLanguage' => 'SpecialMyLanguage',
 178                 'Mypage' => 'SpecialMypage',
 179                 'Mytalk' => 'SpecialMytalk',
 180                 'Myuploads' => 'SpecialMyuploads',
 181                 'AllMyUploads' => 'SpecialAllMyUploads',
 182                 'PermanentLink' => 'SpecialPermanentLink',
 183                 'Redirect' => 'SpecialRedirect',
 184                 'Revisiondelete' => 'SpecialRevisionDelete',
 185                 'RunJobs' => 'SpecialRunJobs',
 186                 'Specialpages' => 'SpecialSpecialpages',
 187         ];
 188
 189         private static $list;
 190         private static $aliases;
 191         private static $pageObjectCache = [];
 192
 193         /**
 194          * Reset the internal list of special pages. Useful when changing $wgSpecialPages after
 195          * the internal list has already been initialized, e.g. during testing.
 196          */
 197         public static function resetList() {
 198                 self::$list = null;
 199                 self::$aliases = null;
 200                 self::$pageObjectCache = [];
 201         }
 202
 203         /**
 204          * Returns a list of canonical special page names.
 205          * May be used to iterate over all registered special pages.
 206          *
 207          * @return string[]
 208          */
 209         public static function getNames() {
 210                 return array_keys( self::getPageList() );
 211         }
 212
 213         /**
 214          * Get the special page list as an array
 215          *
 216          * @deprecated since 1.24, use getNames() instead.
 217          * @return array
 218          */
 219         public static function getList() {
 220                 wfDeprecated( __FUNCTION__, '1.24' );
 221                 return self::getPageList();
 222         }
 223
 224         /**
 225          * Get the special page list as an array
 226          *
 227          * @return array
 228          */
 229         private static function getPageList() {
 230                 global $wgSpecialPages;
 231                 global $wgDisableInternalSearch, $wgEmailAuthentication;
 232                 global $wgEnableEmail, $wgEnableJavaScriptTest;
 233                 global $wgPageLanguageUseDB, $wgContentHandlerUseDB;
 234
 235                 if ( !is_array( self::$list ) ) {
 236
 237                         self::$list = self::$coreList;
 238
 239                         if ( !$wgDisableInternalSearch ) {
 240                                 self::$list['Search'] = 'SpecialSearch';
 241                         }
 242
 243                         if ( $wgEmailAuthentication ) {
 244                                 self::$list['Confirmemail'] = 'EmailConfirmation';
 245                                 self::$list['Invalidateemail'] = 'EmailInvalidation';
 246                         }
 247
 248                         if ( $wgEnableEmail ) {
 249                                 self::$list['ChangeEmail'] = 'SpecialChangeEmail';
 250                         }
 251
 252                         if ( $wgEnableJavaScriptTest ) {
 253                                 self::$list['JavaScriptTest'] = 'SpecialJavaScriptTest';
 254                         }
 255
 256                         if ( $wgPageLanguageUseDB ) {
 257                                 self::$list['PageLanguage'] = 'SpecialPageLanguage';
 258                         }
 259                         if ( $wgContentHandlerUseDB ) {
 260                                 self::$list['ChangeContentModel'] = 'SpecialChangeContentModel';
 261                         }
 262
 263                         // Add extension special pages
 264                         self::$list = array_merge( self::$list, $wgSpecialPages );
 265
 266                         // This hook can be used to disable unwanted core special pages
 267                         // or conditionally register special pages.
 268                         Hooks::run( 'SpecialPage_initList', [ &self::$list ] );
 269
 270                 }
 271
 272                 return self::$list;
 273         }
 274
 275         /**
 276          * Initialise and return the list of special page aliases. Returns an array where
 277          * the key is an alias, and the value is the canonical name of the special page.
 278          * All registered special pages are guaranteed to map to themselves.
 279          * @return array
 280          */
 281         private static function getAliasList() {
 282                 if ( is_null( self::$aliases ) ) {
 283                         global $wgContLang;
 284                         $aliases = $wgContLang->getSpecialPageAliases();
 285                         $pageList = self::getPageList();
 286
 287                         self::$aliases = [];
 288                         $keepAlias = [];
 289
 290                         // Force every canonical name to be an alias for itself.
 291                         foreach ( $pageList as $name => $stuff ) {
 292                                 $caseFoldedAlias = $wgContLang->caseFold( $name );
 293                                 self::$aliases[$caseFoldedAlias] = $name;
 294                                 $keepAlias[$caseFoldedAlias] = 'canonical';
 295                         }
 296
 297                         // Check for $aliases being an array since Language::getSpecialPageAliases can return null
 298                         if ( is_array( $aliases ) ) {
 299                                 foreach ( $aliases as $realName => $aliasList ) {
 300                                         $aliasList = array_values( $aliasList );
 301                                         foreach ( $aliasList as $i => $alias ) {
 302                                                 $caseFoldedAlias = $wgContLang->caseFold( $alias );
 303
 304                                                 if ( isset( self::$aliases[$caseFoldedAlias] ) &&
 305                                                         $realName === self::$aliases[$caseFoldedAlias]
 306                                                 ) {
 307                                                         // Ignore same-realName conflicts
 308                                                         continue;
 309                                                 }
 310
 311                                                 if ( !isset( $keepAlias[$caseFoldedAlias] ) ) {
 312                                                         self::$aliases[$caseFoldedAlias] = $realName;
 313                                                         if ( !$i ) {
 314                                                                 $keepAlias[$caseFoldedAlias] = 'first';
 315                                                         }
 316                                                 } elseif ( !$i ) {
 317                                                         wfWarn( "First alias '$alias' for $realName conflicts with " .
 318                                                                 "{$keepAlias[$caseFoldedAlias]} alias for " .
 319                                                                 self::$aliases[$caseFoldedAlias]
 320                                                         );
 321                                                 }
 322                                         }
 323                                 }
 324                         }
 325                 }
 326
 327                 return self::$aliases;
 328         }
 329
 330         /**
 331          * Given a special page name with a possible subpage, return an array
 332          * where the first element is the special page name and the second is the
 333          * subpage.
 334          *
 335          * @param string $alias
 336          * @return array Array( String, String|null ), or array( null, null ) if the page is invalid
 337          */
 338         public static function resolveAlias( $alias ) {
 339                 global $wgContLang;
 340                 $bits = explode( '/', $alias, 2 );
 341
 342                 $caseFoldedAlias = $wgContLang->caseFold( $bits[0] );
 343                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 344                 $aliases = self::getAliasList();
 345                 if ( isset( $aliases[$caseFoldedAlias] ) ) {
 346                         $name = $aliases[$caseFoldedAlias];
 347                 } else {
 348                         return [ null, null ];
 349                 }
 350
 351                 if ( !isset( $bits[1] ) ) { // bug 2087
 352                         $par = null;
 353                 } else {
 354                         $par = $bits[1];
 355                 }
 356
 357                 return [ $name, $par ];
 358         }
 359
 360         /**
 361          * Check if a given name exist as a special page or as a special page alias
 362          *
 363          * @param string $name Name of a special page
 364          * @return bool True if a special page exists with this name
 365          */
 366         public static function exists( $name ) {
 367                 list( $title, /*...*/ ) = self::resolveAlias( $name );
 368
 369                 $specialPageList = self::getPageList();
 370                 return isset( $specialPageList[$title] );
 371         }
 372
 373         /**
 374          * Find the object with a given name and return it (or NULL)
 375          *
 376          * @param string $name Special page name, may be localised and/or an alias
 377          * @return SpecialPage|null SpecialPage object or null if the page doesn't exist
 378          */
 379         public static function getPage( $name ) {
 380                 list( $realName, /*...*/ ) = self::resolveAlias( $name );
 381
 382                 if ( isset( self::$pageObjectCache[$realName] ) ) {
 383                         return self::$pageObjectCache[$realName];
 384                 }
 385
 386                 $specialPageList = self::getPageList();
 387
 388                 if ( isset( $specialPageList[$realName] ) ) {
 389                         $rec = $specialPageList[$realName];
 390
 391                         if ( is_callable( $rec ) ) {
 392                                 // Use callback to instantiate the special page
 393                                 $page = call_user_func( $rec );
 394                         } elseif ( is_string( $rec ) ) {
 395                                 $className = $rec;
 396                                 $page = new $className;
 397                         } elseif ( is_array( $rec ) ) {
 398                                 $className = array_shift( $rec );
 399                                 // @deprecated, officially since 1.18, unofficially since forever
 400                                 wfDeprecated( "Array syntax for \$wgSpecialPages is deprecated ($className), " .
 401                                         "define a subclass of SpecialPage instead.", '1.18' );
 402                                 $page = ObjectFactory::getObjectFromSpec( [
 403                                         'class' => $className,
 404                                         'args' => $rec,
 405                                         'closure_expansion' => false,
 406                                 ] );
 407                         } elseif ( $rec instanceof SpecialPage ) {
 408                                 $page = $rec; // XXX: we should deep clone here
 409                         } else {
 410                                 $page = null;
 411                         }
 412
 413                         self::$pageObjectCache[$realName] = $page;
 414                         if ( $page instanceof SpecialPage ) {
 415                                 return $page;
 416                         } else {
 417                                 // It's not a classname, nor a callback, nor a legacy constructor array,
 418                                 // nor a special page object. Give up.
 419                                 wfLogWarning( "Cannot instantiate special page $realName: bad spec!" );
 420                                 return null;
 421                         }
 422
 423                 } else {
 424                         return null;
 425                 }
 426         }
 427
 428         /**
 429          * Return categorised listable special pages which are available
 430          * for the current user, and everyone.
 431          *
 432          * @param User $user User object to check permissions, $wgUser will be used
 433          *        if not provided
 434          * @return array ( string => Specialpage )
 435          */
 436         public static function getUsablePages( User $user = null ) {
 437                 $pages = [];
 438                 if ( $user === null ) {
 439                         global $wgUser;
 440                         $user = $wgUser;
 441                 }
 442                 foreach ( self::getPageList() as $name => $rec ) {
 443                         $page = self::getPage( $name );
 444                         if ( $page ) { // not null
 445                                 $page->setContext( RequestContext::getMain() );
 446                                 if ( $page->isListed()
 447                                         && ( !$page->isRestricted() || $page->userCanExecute( $user ) )
 448                                 ) {
 449                                         $pages[$name] = $page;
 450                                 }
 451                         }
 452                 }
 453
 454                 return $pages;
 455         }
 456
 457         /**
 458          * Return categorised listable special pages for all users
 459          *
 460          * @return array ( string => Specialpage )
 461          */
 462         public static function getRegularPages() {
 463                 $pages = [];
 464                 foreach ( self::getPageList() as $name => $rec ) {
 465                         $page = self::getPage( $name );
 466                         if ( $page->isListed() && !$page->isRestricted() ) {
 467                                 $pages[$name] = $page;
 468                         }
 469                 }
 470
 471                 return $pages;
 472         }
 473
 474         /**
 475          * Return categorised listable special pages which are available
 476          * for the current user, but not for everyone
 477          *
 478          * @param User|null $user User object to use or null for $wgUser
 479          * @return array ( string => Specialpage )
 480          */
 481         public static function getRestrictedPages( User $user = null ) {
 482                 $pages = [];
 483                 if ( $user === null ) {
 484                         global $wgUser;
 485                         $user = $wgUser;
 486                 }
 487                 foreach ( self::getPageList() as $name => $rec ) {
 488                         $page = self::getPage( $name );
 489                         if (
 490                                 $page->isListed()
 491                                 && $page->isRestricted()
 492                                 && $page->userCanExecute( $user )
 493                         ) {
 494                                 $pages[$name] = $page;
 495                         }
 496                 }
 497
 498                 return $pages;
 499         }
 500
 501         /**
 502          * Execute a special page path.
 503          * The path may contain parameters, e.g. Special:Name/Params
 504          * Extracts the special page name and call the execute method, passing the parameters
 505          *
 506          * Returns a title object if the page is redirected, false if there was no such special
 507          * page, and true if it was successful.
 508          *
 509          * @param Title $title
 510          * @param IContextSource $context
 511          * @param bool $including Bool output is being captured for use in {{special:whatever}}
 512          * @param LinkRenderer|null $linkRenderer (since 1.28)
 513          *
 514          * @return bool
 515          */
 516         public static function executePath( Title &$title, IContextSource &$context, $including = false,
 517                 LinkRenderer $linkRenderer = null
 518         ) {
 519                 // @todo FIXME: Redirects broken due to this call
 520                 $bits = explode( '/', $title->getDBkey(), 2 );
 521                 $name = $bits[0];
 522                 if ( !isset( $bits[1] ) ) { // bug 2087
 523                         $par = null;
 524                 } else {
 525                         $par = $bits[1];
 526                 }
 527
 528                 $page = self::getPage( $name );
 529                 if ( !$page ) {
 530                         $context->getOutput()->setArticleRelated( false );
 531                         $context->getOutput()->setRobotPolicy( 'noindex,nofollow' );
 532
 533                         global $wgSend404Code;
 534                         if ( $wgSend404Code ) {
 535                                 $context->getOutput()->setStatusCode( 404 );
 536                         }
 537
 538                         $context->getOutput()->showErrorPage( 'nosuchspecialpage', 'nospecialpagetext' );
 539
 540                         return false;
 541                 }
 542
 543                 if ( !$including ) {
 544                         // Narrow DB query expectations for this HTTP request
 545                         $trxLimits = $context->getConfig()->get( 'TrxProfilerLimits' );
 546                         $trxProfiler = Profiler::instance()->getTransactionProfiler();
 547                         if ( $context->getRequest()->wasPosted() && !$page->doesWrites() ) {
 548                                 $trxProfiler->setExpectations( $trxLimits['POST-nonwrite'], __METHOD__ );
 549                                 $context->getRequest()->markAsSafeRequest();
 550                         }
 551                 }
 552
 553                 // Page exists, set the context
 554                 $page->setContext( $context );
 555
 556                 if ( !$including ) {
 557                         // Redirect to canonical alias for GET commands
 558                         // Not for POST, we'd lose the post data, so it's best to just distribute
 559                         // the request. Such POST requests are possible for old extensions that
 560                         // generate self-links without being aware that their default name has
 561                         // changed.
 562                         if ( $name != $page->getLocalName() && !$context->getRequest()->wasPosted() ) {
 563                                 $query = $context->getRequest()->getQueryValues();
 564                                 unset( $query['title'] );
 565                                 $title = $page->getPageTitle( $par );
 566                                 $url = $title->getFullURL( $query );
 567                                 $context->getOutput()->redirect( $url );
 568
 569                                 return $title;
 570                         } else {
 571                                 $context->setTitle( $page->getPageTitle( $par ) );
 572                         }
 573                 } elseif ( !$page->isIncludable() ) {
 574                         return false;
 575                 }
 576
 577                 $page->including( $including );
 578                 if ( $linkRenderer ) {
 579                         $page->setLinkRenderer( $linkRenderer );
 580                 }
 581
 582                 // Execute special page
 583                 $page->run( $par );
 584
 585                 return true;
 586         }
 587
 588         /**
 589          * Just like executePath() but will override global variables and execute
 590          * the page in "inclusion" mode. Returns true if the execution was
 591          * successful or false if there was no such special page, or a title object
 592          * if it was a redirect.
 593          *
 594          * Also saves the current $wgTitle, $wgOut, $wgRequest, $wgUser and $wgLang
 595          * variables so that the special page will get the context it'd expect on a
 596          * normal request, and then restores them to their previous values after.
 597          *
 598          * @param Title $title
 599          * @param IContextSource $context
 600          * @param LinkRenderer|null $linkRenderer (since 1.28)
 601          * @return string HTML fragment
 602          */
 603         public static function capturePath(
 604                 Title $title, IContextSource $context, LinkRenderer $linkRenderer = null
 605         ) {
 606                 global $wgTitle, $wgOut, $wgRequest, $wgUser, $wgLang;
 607                 $main = RequestContext::getMain();
 608
 609                 // Save current globals and main context
 610                 $glob = [
 611                         'title' => $wgTitle,
 612                         'output' => $wgOut,
 613                         'request' => $wgRequest,
 614                         'user' => $wgUser,
 615                         'language' => $wgLang,
 616                 ];
 617                 $ctx = [
 618                         'title' => $main->getTitle(),
 619                         'output' => $main->getOutput(),
 620                         'request' => $main->getRequest(),
 621                         'user' => $main->getUser(),
 622                         'language' => $main->getLanguage(),
 623                 ];
 624
 625                 // Override
 626                 $wgTitle = $title;
 627                 $wgOut = $context->getOutput();
 628                 $wgRequest = $context->getRequest();
 629                 $wgUser = $context->getUser();
 630                 $wgLang = $context->getLanguage();
 631                 $main->setTitle( $title );
 632                 $main->setOutput( $context->getOutput() );
 633                 $main->setRequest( $context->getRequest() );
 634                 $main->setUser( $context->getUser() );
 635                 $main->setLanguage( $context->getLanguage() );
 636
 637                 // The useful part
 638                 $ret = self::executePath( $title, $context, true, $linkRenderer );
 639
 640                 // Restore old globals and context
 641                 $wgTitle = $glob['title'];
 642                 $wgOut = $glob['output'];
 643                 $wgRequest = $glob['request'];
 644                 $wgUser = $glob['user'];
 645                 $wgLang = $glob['language'];
 646                 $main->setTitle( $ctx['title'] );
 647                 $main->setOutput( $ctx['output'] );
 648                 $main->setRequest( $ctx['request'] );
 649                 $main->setUser( $ctx['user'] );
 650                 $main->setLanguage( $ctx['language'] );
 651
 652                 return $ret;
 653         }
 654
 655         /**
 656          * Get the local name for a specified canonical name
 657          *
 658          * @param string $name
 659          * @param string|bool $subpage
 660          * @return string
 661          */
 662         public static function getLocalNameFor( $name, $subpage = false ) {
 663                 global $wgContLang;
 664                 $aliases = $wgContLang->getSpecialPageAliases();
 665                 $aliasList = self::getAliasList();
 666
 667                 // Find the first alias that maps back to $name
 668                 if ( isset( $aliases[$name] ) ) {
 669                         $found = false;
 670                         foreach ( $aliases[$name] as $alias ) {
 671                                 $caseFoldedAlias = $wgContLang->caseFold( $alias );
 672                                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 673                                 if ( isset( $aliasList[$caseFoldedAlias] ) &&
 674                                         $aliasList[$caseFoldedAlias] === $name
 675                                 ) {
 676                                         $name = $alias;
 677                                         $found = true;
 678                                         break;
 679                                 }
 680                         }
 681                         if ( !$found ) {
 682                                 wfWarn( "Did not find a usable alias for special page '$name'. " .
 683                                         "It seems all defined aliases conflict?" );
 684                         }
 685                 } else {
 686                         // Check if someone misspelled the correct casing
 687                         if ( is_array( $aliases ) ) {
 688                                 foreach ( $aliases as $n => $values ) {
 689                                         if ( strcasecmp( $name, $n ) === 0 ) {
 690                                                 wfWarn( "Found alias defined for $n when searching for " .
 691                                                         "special page aliases for $name. Case mismatch?" );
 692                                                 return self::getLocalNameFor( $n, $subpage );
 693                                         }
 694                                 }
 695                         }
 696
 697                         wfWarn( "Did not find alias for special page '$name'. " .
 698                                 "Perhaps no aliases are defined for it?" );
 699                 }
 700
 701                 if ( $subpage !== false && !is_null( $subpage ) ) {
 702                         // Make sure it's in dbkey form
 703                         $subpage = str_replace( ' ', '_', $subpage );
 704                         $name = "$name/$subpage";
 705                 }
 706
 707                 return $wgContLang->ucfirst( $name );
 708         }
 709
 710         /**
 711          * Get a title for a given alias
 712          *
 713          * @param string $alias
 714          * @return Title|null Title or null if there is no such alias
 715          */
 716         public static function getTitleForAlias( $alias ) {
 717                 list( $name, $subpage ) = self::resolveAlias( $alias );
 718                 if ( $name != null ) {
 719                         return SpecialPage::getTitleFor( $name, $subpage );
 720                 } else {
 721                         return null;
 722                 }
 723         }
 724 }