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                 'GoToInterwiki' => 'SpecialGoToInterwiki',
 148
 149                 // High use pages
 150                 'Mostlinkedcategories' => 'MostlinkedCategoriesPage',
 151                 'Mostimages' => 'MostimagesPage',
 152                 'Mostinterwikis' => 'MostinterwikisPage',
 153                 'Mostlinked' => 'MostlinkedPage',
 154                 'Mostlinkedtemplates' => 'MostlinkedTemplatesPage',
 155                 'Mostcategories' => 'MostcategoriesPage',
 156                 'Mostrevisions' => 'MostrevisionsPage',
 157
 158                 // Page tools
 159                 'ComparePages' => 'SpecialComparePages',
 160                 'Export' => 'SpecialExport',
 161                 'Import' => 'SpecialImport',
 162                 'Undelete' => 'SpecialUndelete',
 163                 'Whatlinkshere' => 'SpecialWhatLinksHere',
 164                 'MergeHistory' => 'SpecialMergeHistory',
 165                 'ExpandTemplates' => 'SpecialExpandTemplates',
 166
 167                 // Other
 168                 'Booksources' => 'SpecialBookSources',
 169
 170                 // Unlisted / redirects
 171                 'ApiHelp' => 'SpecialApiHelp',
 172                 'Blankpage' => 'SpecialBlankpage',
 173                 'Diff' => 'SpecialDiff',
 174                 'EditTags' => 'SpecialEditTags',
 175                 'Emailuser' => 'SpecialEmailUser',
 176                 'Movepage' => 'MovePageForm',
 177                 'Mycontributions' => 'SpecialMycontributions',
 178                 'MyLanguage' => 'SpecialMyLanguage',
 179                 'Mypage' => 'SpecialMypage',
 180                 'Mytalk' => 'SpecialMytalk',
 181                 'Myuploads' => 'SpecialMyuploads',
 182                 'AllMyUploads' => 'SpecialAllMyUploads',
 183                 'PermanentLink' => 'SpecialPermanentLink',
 184                 'Redirect' => 'SpecialRedirect',
 185                 'Revisiondelete' => 'SpecialRevisionDelete',
 186                 'RunJobs' => 'SpecialRunJobs',
 187                 'Specialpages' => 'SpecialSpecialpages',
 188         ];
 189
 190         private static $list;
 191         private static $aliases;
 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         }
 201
 202         /**
 203          * Returns a list of canonical special page names.
 204          * May be used to iterate over all registered special pages.
 205          *
 206          * @return string[]
 207          */
 208         public static function getNames() {
 209                 return array_keys( self::getPageList() );
 210         }
 211
 212         /**
 213          * Get the special page list as an array
 214          *
 215          * @deprecated since 1.24, use getNames() instead.
 216          * @return array
 217          */
 218         public static function getList() {
 219                 wfDeprecated( __FUNCTION__, '1.24' );
 220                 return self::getPageList();
 221         }
 222
 223         /**
 224          * Get the special page list as an array
 225          *
 226          * @return array
 227          */
 228         private static function getPageList() {
 229                 global $wgSpecialPages;
 230                 global $wgDisableInternalSearch, $wgEmailAuthentication;
 231                 global $wgEnableEmail, $wgEnableJavaScriptTest;
 232                 global $wgPageLanguageUseDB, $wgContentHandlerUseDB;
 233
 234                 if ( !is_array( self::$list ) ) {
 235
 236                         self::$list = self::$coreList;
 237
 238                         if ( !$wgDisableInternalSearch ) {
 239                                 self::$list['Search'] = 'SpecialSearch';
 240                         }
 241
 242                         if ( $wgEmailAuthentication ) {
 243                                 self::$list['Confirmemail'] = 'EmailConfirmation';
 244                                 self::$list['Invalidateemail'] = 'EmailInvalidation';
 245                         }
 246
 247                         if ( $wgEnableEmail ) {
 248                                 self::$list['ChangeEmail'] = 'SpecialChangeEmail';
 249                         }
 250
 251                         if ( $wgEnableJavaScriptTest ) {
 252                                 self::$list['JavaScriptTest'] = 'SpecialJavaScriptTest';
 253                         }
 254
 255                         if ( $wgPageLanguageUseDB ) {
 256                                 self::$list['PageLanguage'] = 'SpecialPageLanguage';
 257                         }
 258                         if ( $wgContentHandlerUseDB ) {
 259                                 self::$list['ChangeContentModel'] = 'SpecialChangeContentModel';
 260                         }
 261
 262                         // Add extension special pages
 263                         self::$list = array_merge( self::$list, $wgSpecialPages );
 264
 265                         // This hook can be used to disable unwanted core special pages
 266                         // or conditionally register special pages.
 267                         Hooks::run( 'SpecialPage_initList', [ &self::$list ] );
 268
 269                 }
 270
 271                 return self::$list;
 272         }
 273
 274         /**
 275          * Initialise and return the list of special page aliases. Returns an array where
 276          * the key is an alias, and the value is the canonical name of the special page.
 277          * All registered special pages are guaranteed to map to themselves.
 278          * @return array
 279          */
 280         private static function getAliasList() {
 281                 if ( is_null( self::$aliases ) ) {
 282                         global $wgContLang;
 283                         $aliases = $wgContLang->getSpecialPageAliases();
 284                         $pageList = self::getPageList();
 285
 286                         self::$aliases = [];
 287                         $keepAlias = [];
 288
 289                         // Force every canonical name to be an alias for itself.
 290                         foreach ( $pageList as $name => $stuff ) {
 291                                 $caseFoldedAlias = $wgContLang->caseFold( $name );
 292                                 self::$aliases[$caseFoldedAlias] = $name;
 293                                 $keepAlias[$caseFoldedAlias] = 'canonical';
 294                         }
 295
 296                         // Check for $aliases being an array since Language::getSpecialPageAliases can return null
 297                         if ( is_array( $aliases ) ) {
 298                                 foreach ( $aliases as $realName => $aliasList ) {
 299                                         $aliasList = array_values( $aliasList );
 300                                         foreach ( $aliasList as $i => $alias ) {
 301                                                 $caseFoldedAlias = $wgContLang->caseFold( $alias );
 302
 303                                                 if ( isset( self::$aliases[$caseFoldedAlias] ) &&
 304                                                         $realName === self::$aliases[$caseFoldedAlias]
 305                                                 ) {
 306                                                         // Ignore same-realName conflicts
 307                                                         continue;
 308                                                 }
 309
 310                                                 if ( !isset( $keepAlias[$caseFoldedAlias] ) ) {
 311                                                         self::$aliases[$caseFoldedAlias] = $realName;
 312                                                         if ( !$i ) {
 313                                                                 $keepAlias[$caseFoldedAlias] = 'first';
 314                                                         }
 315                                                 } elseif ( !$i ) {
 316                                                         wfWarn( "First alias '$alias' for $realName conflicts with " .
 317                                                                 "{$keepAlias[$caseFoldedAlias]} alias for " .
 318                                                                 self::$aliases[$caseFoldedAlias]
 319                                                         );
 320                                                 }
 321                                         }
 322                                 }
 323                         }
 324                 }
 325
 326                 return self::$aliases;
 327         }
 328
 329         /**
 330          * Given a special page name with a possible subpage, return an array
 331          * where the first element is the special page name and the second is the
 332          * subpage.
 333          *
 334          * @param string $alias
 335          * @return array Array( String, String|null ), or array( null, null ) if the page is invalid
 336          */
 337         public static function resolveAlias( $alias ) {
 338                 global $wgContLang;
 339                 $bits = explode( '/', $alias, 2 );
 340
 341                 $caseFoldedAlias = $wgContLang->caseFold( $bits[0] );
 342                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 343                 $aliases = self::getAliasList();
 344                 if ( isset( $aliases[$caseFoldedAlias] ) ) {
 345                         $name = $aliases[$caseFoldedAlias];
 346                 } else {
 347                         return [ null, null ];
 348                 }
 349
 350                 if ( !isset( $bits[1] ) ) { // T4087
 351                         $par = null;
 352                 } else {
 353                         $par = $bits[1];
 354                 }
 355
 356                 return [ $name, $par ];
 357         }
 358
 359         /**
 360          * Check if a given name exist as a special page or as a special page alias
 361          *
 362          * @param string $name Name of a special page
 363          * @return bool True if a special page exists with this name
 364          */
 365         public static function exists( $name ) {
 366                 list( $title, /*...*/ ) = self::resolveAlias( $name );
 367
 368                 $specialPageList = self::getPageList();
 369                 return isset( $specialPageList[$title] );
 370         }
 371
 372         /**
 373          * Find the object with a given name and return it (or NULL)
 374          *
 375          * @param string $name Special page name, may be localised and/or an alias
 376          * @return SpecialPage|null SpecialPage object or null if the page doesn't exist
 377          */
 378         public static function getPage( $name ) {
 379                 list( $realName, /*...*/ ) = self::resolveAlias( $name );
 380
 381                 $specialPageList = self::getPageList();
 382
 383                 if ( isset( $specialPageList[$realName] ) ) {
 384                         $rec = $specialPageList[$realName];
 385
 386                         if ( is_callable( $rec ) ) {
 387                                 // Use callback to instantiate the special page
 388                                 $page = call_user_func( $rec );
 389                         } elseif ( is_string( $rec ) ) {
 390                                 $className = $rec;
 391                                 $page = new $className;
 392                         } elseif ( is_array( $rec ) ) {
 393                                 $className = array_shift( $rec );
 394                                 // @deprecated, officially since 1.18, unofficially since forever
 395                                 wfDeprecated( "Array syntax for \$wgSpecialPages is deprecated ($className), " .
 396                                         "define a subclass of SpecialPage instead.", '1.18' );
 397                                 $page = ObjectFactory::getObjectFromSpec( [
 398                                         'class' => $className,
 399                                         'args' => $rec,
 400                                         'closure_expansion' => false,
 401                                 ] );
 402                         } elseif ( $rec instanceof SpecialPage ) {
 403                                 $page = $rec; // XXX: we should deep clone here
 404                         } else {
 405                                 $page = null;
 406                         }
 407
 408                         if ( $page instanceof SpecialPage ) {
 409                                 return $page;
 410                         } else {
 411                                 // It's not a classname, nor a callback, nor a legacy constructor array,
 412                                 // nor a special page object. Give up.
 413                                 wfLogWarning( "Cannot instantiate special page $realName: bad spec!" );
 414                                 return null;
 415                         }
 416
 417                 } else {
 418                         return null;
 419                 }
 420         }
 421
 422         /**
 423          * Return categorised listable special pages which are available
 424          * for the current user, and everyone.
 425          *
 426          * @param User $user User object to check permissions, $wgUser will be used
 427          *        if not provided
 428          * @return array ( string => Specialpage )
 429          */
 430         public static function getUsablePages( User $user = null ) {
 431                 $pages = [];
 432                 if ( $user === null ) {
 433                         global $wgUser;
 434                         $user = $wgUser;
 435                 }
 436                 foreach ( self::getPageList() as $name => $rec ) {
 437                         $page = self::getPage( $name );
 438                         if ( $page ) { // not null
 439                                 $page->setContext( RequestContext::getMain() );
 440                                 if ( $page->isListed()
 441                                         && ( !$page->isRestricted() || $page->userCanExecute( $user ) )
 442                                 ) {
 443                                         $pages[$name] = $page;
 444                                 }
 445                         }
 446                 }
 447
 448                 return $pages;
 449         }
 450
 451         /**
 452          * Return categorised listable special pages for all users
 453          *
 454          * @return array ( string => Specialpage )
 455          */
 456         public static function getRegularPages() {
 457                 $pages = [];
 458                 foreach ( self::getPageList() as $name => $rec ) {
 459                         $page = self::getPage( $name );
 460                         if ( $page->isListed() && !$page->isRestricted() ) {
 461                                 $pages[$name] = $page;
 462                         }
 463                 }
 464
 465                 return $pages;
 466         }
 467
 468         /**
 469          * Return categorised listable special pages which are available
 470          * for the current user, but not for everyone
 471          *
 472          * @param User|null $user User object to use or null for $wgUser
 473          * @return array ( string => Specialpage )
 474          */
 475         public static function getRestrictedPages( User $user = null ) {
 476                 $pages = [];
 477                 if ( $user === null ) {
 478                         global $wgUser;
 479                         $user = $wgUser;
 480                 }
 481                 foreach ( self::getPageList() as $name => $rec ) {
 482                         $page = self::getPage( $name );
 483                         if (
 484                                 $page->isListed()
 485                                 && $page->isRestricted()
 486                                 && $page->userCanExecute( $user )
 487                         ) {
 488                                 $pages[$name] = $page;
 489                         }
 490                 }
 491
 492                 return $pages;
 493         }
 494
 495         /**
 496          * Execute a special page path.
 497          * The path may contain parameters, e.g. Special:Name/Params
 498          * Extracts the special page name and call the execute method, passing the parameters
 499          *
 500          * Returns a title object if the page is redirected, false if there was no such special
 501          * page, and true if it was successful.
 502          *
 503          * @param Title $title
 504          * @param IContextSource $context
 505          * @param bool $including Bool output is being captured for use in {{special:whatever}}
 506          * @param LinkRenderer|null $linkRenderer (since 1.28)
 507          *
 508          * @return bool
 509          */
 510         public static function executePath( Title &$title, IContextSource &$context, $including = false,
 511                 LinkRenderer $linkRenderer = null
 512         ) {
 513                 // @todo FIXME: Redirects broken due to this call
 514                 $bits = explode( '/', $title->getDBkey(), 2 );
 515                 $name = $bits[0];
 516                 if ( !isset( $bits[1] ) ) { // T4087
 517                         $par = null;
 518                 } else {
 519                         $par = $bits[1];
 520                 }
 521
 522                 $page = self::getPage( $name );
 523                 if ( !$page ) {
 524                         $context->getOutput()->setArticleRelated( false );
 525                         $context->getOutput()->setRobotPolicy( 'noindex,nofollow' );
 526
 527                         global $wgSend404Code;
 528                         if ( $wgSend404Code ) {
 529                                 $context->getOutput()->setStatusCode( 404 );
 530                         }
 531
 532                         $context->getOutput()->showErrorPage( 'nosuchspecialpage', 'nospecialpagetext' );
 533
 534                         return false;
 535                 }
 536
 537                 if ( !$including ) {
 538                         // Narrow DB query expectations for this HTTP request
 539                         $trxLimits = $context->getConfig()->get( 'TrxProfilerLimits' );
 540                         $trxProfiler = Profiler::instance()->getTransactionProfiler();
 541                         if ( $context->getRequest()->wasPosted() && !$page->doesWrites() ) {
 542                                 $trxProfiler->setExpectations( $trxLimits['POST-nonwrite'], __METHOD__ );
 543                                 $context->getRequest()->markAsSafeRequest();
 544                         }
 545                 }
 546
 547                 // Page exists, set the context
 548                 $page->setContext( $context );
 549
 550                 if ( !$including ) {
 551                         // Redirect to canonical alias for GET commands
 552                         // Not for POST, we'd lose the post data, so it's best to just distribute
 553                         // the request. Such POST requests are possible for old extensions that
 554                         // generate self-links without being aware that their default name has
 555                         // changed.
 556                         if ( $name != $page->getLocalName() && !$context->getRequest()->wasPosted() ) {
 557                                 $query = $context->getRequest()->getQueryValues();
 558                                 unset( $query['title'] );
 559                                 $title = $page->getPageTitle( $par );
 560                                 $url = $title->getFullURL( $query );
 561                                 $context->getOutput()->redirect( $url );
 562
 563                                 return $title;
 564                         } else {
 565                                 $context->setTitle( $page->getPageTitle( $par ) );
 566                         }
 567                 } elseif ( !$page->isIncludable() ) {
 568                         return false;
 569                 }
 570
 571                 $page->including( $including );
 572                 if ( $linkRenderer ) {
 573                         $page->setLinkRenderer( $linkRenderer );
 574                 }
 575
 576                 // Execute special page
 577                 $page->run( $par );
 578
 579                 return true;
 580         }
 581
 582         /**
 583          * Just like executePath() but will override global variables and execute
 584          * the page in "inclusion" mode. Returns true if the execution was
 585          * successful or false if there was no such special page, or a title object
 586          * if it was a redirect.
 587          *
 588          * Also saves the current $wgTitle, $wgOut, $wgRequest, $wgUser and $wgLang
 589          * variables so that the special page will get the context it'd expect on a
 590          * normal request, and then restores them to their previous values after.
 591          *
 592          * @param Title $title
 593          * @param IContextSource $context
 594          * @param LinkRenderer|null $linkRenderer (since 1.28)
 595          * @return string HTML fragment
 596          */
 597         public static function capturePath(
 598                 Title $title, IContextSource $context, LinkRenderer $linkRenderer = null
 599         ) {
 600                 global $wgTitle, $wgOut, $wgRequest, $wgUser, $wgLang;
 601                 $main = RequestContext::getMain();
 602
 603                 // Save current globals and main context
 604                 $glob = [
 605                         'title' => $wgTitle,
 606                         'output' => $wgOut,
 607                         'request' => $wgRequest,
 608                         'user' => $wgUser,
 609                         'language' => $wgLang,
 610                 ];
 611                 $ctx = [
 612                         'title' => $main->getTitle(),
 613                         'output' => $main->getOutput(),
 614                         'request' => $main->getRequest(),
 615                         'user' => $main->getUser(),
 616                         'language' => $main->getLanguage(),
 617                 ];
 618
 619                 // Override
 620                 $wgTitle = $title;
 621                 $wgOut = $context->getOutput();
 622                 $wgRequest = $context->getRequest();
 623                 $wgUser = $context->getUser();
 624                 $wgLang = $context->getLanguage();
 625                 $main->setTitle( $title );
 626                 $main->setOutput( $context->getOutput() );
 627                 $main->setRequest( $context->getRequest() );
 628                 $main->setUser( $context->getUser() );
 629                 $main->setLanguage( $context->getLanguage() );
 630
 631                 // The useful part
 632                 $ret = self::executePath( $title, $context, true, $linkRenderer );
 633
 634                 // Restore old globals and context
 635                 $wgTitle = $glob['title'];
 636                 $wgOut = $glob['output'];
 637                 $wgRequest = $glob['request'];
 638                 $wgUser = $glob['user'];
 639                 $wgLang = $glob['language'];
 640                 $main->setTitle( $ctx['title'] );
 641                 $main->setOutput( $ctx['output'] );
 642                 $main->setRequest( $ctx['request'] );
 643                 $main->setUser( $ctx['user'] );
 644                 $main->setLanguage( $ctx['language'] );
 645
 646                 return $ret;
 647         }
 648
 649         /**
 650          * Get the local name for a specified canonical name
 651          *
 652          * @param string $name
 653          * @param string|bool $subpage
 654          * @return string
 655          */
 656         public static function getLocalNameFor( $name, $subpage = false ) {
 657                 global $wgContLang;
 658                 $aliases = $wgContLang->getSpecialPageAliases();
 659                 $aliasList = self::getAliasList();
 660
 661                 // Find the first alias that maps back to $name
 662                 if ( isset( $aliases[$name] ) ) {
 663                         $found = false;
 664                         foreach ( $aliases[$name] as $alias ) {
 665                                 $caseFoldedAlias = $wgContLang->caseFold( $alias );
 666                                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 667                                 if ( isset( $aliasList[$caseFoldedAlias] ) &&
 668                                         $aliasList[$caseFoldedAlias] === $name
 669                                 ) {
 670                                         $name = $alias;
 671                                         $found = true;
 672                                         break;
 673                                 }
 674                         }
 675                         if ( !$found ) {
 676                                 wfWarn( "Did not find a usable alias for special page '$name'. " .
 677                                         "It seems all defined aliases conflict?" );
 678                         }
 679                 } else {
 680                         // Check if someone misspelled the correct casing
 681                         if ( is_array( $aliases ) ) {
 682                                 foreach ( $aliases as $n => $values ) {
 683                                         if ( strcasecmp( $name, $n ) === 0 ) {
 684                                                 wfWarn( "Found alias defined for $n when searching for " .
 685                                                         "special page aliases for $name. Case mismatch?" );
 686                                                 return self::getLocalNameFor( $n, $subpage );
 687                                         }
 688                                 }
 689                         }
 690
 691                         wfWarn( "Did not find alias for special page '$name'. " .
 692                                 "Perhaps no aliases are defined for it?" );
 693                 }
 694
 695                 if ( $subpage !== false && !is_null( $subpage ) ) {
 696                         // Make sure it's in dbkey form
 697                         $subpage = str_replace( ' ', '_', $subpage );
 698                         $name = "$name/$subpage";
 699                 }
 700
 701                 return $wgContLang->ucfirst( $name );
 702         }
 703
 704         /**
 705          * Get a title for a given alias
 706          *
 707          * @param string $alias
 708          * @return Title|null Title or null if there is no such alias
 709          */
 710         public static function getTitleForAlias( $alias ) {
 711                 list( $name, $subpage ) = self::resolveAlias( $alias );
 712                 if ( $name != null ) {
 713                         return SpecialPage::getTitleFor( $name, $subpage );
 714                 } else {
 715                         return null;
 716                 }
 717         }
 718 }