includes/title/NamespaceInfo.php

   1 <?php
   2 /**
   3  * Provide things related to namespaces.
   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  */
  22
  23 use MediaWiki\Config\ServiceOptions;
  24 use MediaWiki\Linker\LinkTarget;
  25 use MediaWiki\MediaWikiServices;
  26
  27 /**
  28  * This is a utility class for dealing with namespaces that encodes all the "magic" behaviors of
  29  * them based on index.  The textual names of the namespaces are handled by Language.php.
  30  *
  31  * @since 1.34
  32  */
  33 class NamespaceInfo {
  34
  35         /**
  36          * These namespaces should always be first-letter capitalized, now and
  37          * forevermore. Historically, they could've probably been lowercased too,
  38          * but some things are just too ingrained now. :)
  39          */
  40         private $alwaysCapitalizedNamespaces = [ NS_SPECIAL, NS_USER, NS_MEDIAWIKI ];
  41
  42         /** @var string[]|null Canonical namespaces cache */
  43         private $canonicalNamespaces = null;
  44
  45         /** @var array|false Canonical namespaces index cache */
  46         private $namespaceIndexes = false;
  47
  48         /** @var int[]|null Valid namespaces cache */
  49         private $validNamespaces = null;
  50
  51         /** @var ServiceOptions */
  52         private $options;
  53
  54         /**
  55          * Definitions of the NS_ constants are in Defines.php
  56          *
  57          * @todo Make this const when HHVM support is dropped (T192166)
  58          *
  59          * @var array
  60          * @internal
  61          */
  62         public static $canonicalNames = [
  63                 NS_MEDIA            => 'Media',
  64                 NS_SPECIAL          => 'Special',
  65                 NS_MAIN             => '',
  66                 NS_TALK             => 'Talk',
  67                 NS_USER             => 'User',
  68                 NS_USER_TALK        => 'User_talk',
  69                 NS_PROJECT          => 'Project',
  70                 NS_PROJECT_TALK     => 'Project_talk',
  71                 NS_FILE             => 'File',
  72                 NS_FILE_TALK        => 'File_talk',
  73                 NS_MEDIAWIKI        => 'MediaWiki',
  74                 NS_MEDIAWIKI_TALK   => 'MediaWiki_talk',
  75                 NS_TEMPLATE         => 'Template',
  76                 NS_TEMPLATE_TALK    => 'Template_talk',
  77                 NS_HELP             => 'Help',
  78                 NS_HELP_TALK        => 'Help_talk',
  79                 NS_CATEGORY         => 'Category',
  80                 NS_CATEGORY_TALK    => 'Category_talk',
  81         ];
  82
  83         /**
  84          * TODO Make this const when HHVM support is dropped (T192166)
  85          *
  86          * @since 1.34
  87          * @var array
  88          */
  89         public static $constructorOptions = [
  90                 'AllowImageMoving',
  91                 'CanonicalNamespaceNames',
  92                 'CapitalLinkOverrides',
  93                 'CapitalLinks',
  94                 'ContentNamespaces',
  95                 'ExtraNamespaces',
  96                 'ExtraSignatureNamespaces',
  97                 'NamespaceContentModels',
  98                 'NamespacesWithSubpages',
  99                 'NonincludableNamespaces',
 100         ];
 101
 102         /**
 103          * @param ServiceOptions $options
 104          */
 105         public function __construct( ServiceOptions $options ) {
 106                 $options->assertRequiredOptions( self::$constructorOptions );
 107                 $this->options = $options;
 108         }
 109
 110         /**
 111          * Throw an exception when trying to get the subject or talk page
 112          * for a given namespace where it does not make sense.
 113          * Special namespaces are defined in includes/Defines.php and have
 114          * a value below 0 (ex: NS_SPECIAL = -1 , NS_MEDIA = -2)
 115          *
 116          * @param int $index
 117          * @param string $method
 118          *
 119          * @throws MWException
 120          * @return bool
 121          */
 122         private function isMethodValidFor( $index, $method ) {
 123                 if ( $index < NS_MAIN ) {
 124                         throw new MWException( "$method does not make any sense for given namespace $index" );
 125                 }
 126                 return true;
 127         }
 128
 129         /**
 130          * Can pages in the given namespace be moved?
 131          *
 132          * @param int $index Namespace index
 133          * @return bool
 134          */
 135         public function isMovable( $index ) {
 136                 $result = $index >= NS_MAIN &&
 137                         ( $index != NS_FILE || $this->options->get( 'AllowImageMoving' ) );
 138
 139                 /**
 140                  * @since 1.20
 141                  */
 142                 Hooks::run( 'NamespaceIsMovable', [ $index, &$result ] );
 143
 144                 return $result;
 145         }
 146
 147         /**
 148          * Is the given namespace is a subject (non-talk) namespace?
 149          *
 150          * @param int $index Namespace index
 151          * @return bool
 152          */
 153         public function isSubject( $index ) {
 154                 return !$this->isTalk( $index );
 155         }
 156
 157         /**
 158          * Is the given namespace a talk namespace?
 159          *
 160          * @param int $index Namespace index
 161          * @return bool
 162          */
 163         public function isTalk( $index ) {
 164                 return $index > NS_MAIN
 165                         && $index % 2;
 166         }
 167
 168         /**
 169          * Get the talk namespace index for a given namespace
 170          *
 171          * @param int $index Namespace index
 172          * @return int
 173          * @throws MWException if the given namespace doesn't have an associated talk namespace
 174          *         (e.g. NS_SPECIAL).
 175          */
 176         public function getTalk( $index ) {
 177                 $this->isMethodValidFor( $index, __METHOD__ );
 178                 return $this->isTalk( $index )
 179                         ? $index
 180                         : $index + 1;
 181         }
 182
 183         /**
 184          * Get a LinkTarget referring to the talk page of $target.
 185          *
 186          * @see canHaveTalkPage
 187          * @param LinkTarget $target
 188          * @return LinkTarget Talk page for $target
 189          * @throws MWException if $target doesn't have talk pages, e.g. because it's in NS_SPECIAL,
 190          *         because it's a relative section-only link, or it's an an interwiki link.
 191          */
 192         public function getTalkPage( LinkTarget $target ) : LinkTarget {
 193                 if ( $target->getText() === '' ) {
 194                         throw new MWException( 'Can\'t determine talk page associated with relative section link' );
 195                 }
 196
 197                 if ( $target->getInterwiki() !== '' ) {
 198                         throw new MWException( 'Can\'t determine talk page associated with interwiki link' );
 199                 }
 200
 201                 if ( $this->isTalk( $target->getNamespace() ) ) {
 202                         return $target;
 203                 }
 204
 205                 // NOTE: getTalk throws on bad namespaces!
 206                 return new TitleValue( $this->getTalk( $target->getNamespace() ), $target->getDBkey() );
 207         }
 208
 209         /**
 210          * Can the title have a corresponding talk page?
 211          *
 212          * False for relative section-only links (with getText() === ''),
 213          * interwiki links (with getInterwiki() !== ''), and pages in NS_SPECIAL.
 214          *
 215          * @see getTalkPage
 216          *
 217          * @param LinkTarget $target
 218          * @return bool True if this title either is a talk page or can have a talk page associated.
 219          */
 220         public function canHaveTalkPage( LinkTarget $target ) {
 221                 if ( $target->getText() === '' || $target->getInterwiki() !== '' ) {
 222                         return false;
 223                 }
 224
 225                 if ( $target->getNamespace() < NS_MAIN ) {
 226                         return false;
 227                 }
 228
 229                 return true;
 230         }
 231
 232         /**
 233          * Get the subject namespace index for a given namespace
 234          * Special namespaces (NS_MEDIA, NS_SPECIAL) are always the subject.
 235          *
 236          * @param int $index Namespace index
 237          * @return int
 238          */
 239         public function getSubject( $index ) {
 240                 # Handle special namespaces
 241                 if ( $index < NS_MAIN ) {
 242                         return $index;
 243                 }
 244
 245                 return $this->isTalk( $index )
 246                         ? $index - 1
 247                         : $index;
 248         }
 249
 250         /**
 251          * @param LinkTarget $target
 252          * @return LinkTarget Subject page for $target
 253          */
 254         public function getSubjectPage( LinkTarget $target ) : LinkTarget {
 255                 if ( $this->isSubject( $target->getNamespace() ) ) {
 256                         return $target;
 257                 }
 258                 return new TitleValue( $this->getSubject( $target->getNamespace() ), $target->getDBkey() );
 259         }
 260
 261         /**
 262          * Get the associated namespace.
 263          * For talk namespaces, returns the subject (non-talk) namespace
 264          * For subject (non-talk) namespaces, returns the talk namespace
 265          *
 266          * @param int $index Namespace index
 267          * @return int
 268          * @throws MWException if called on a namespace that has no talk pages (e.g., NS_SPECIAL)
 269          */
 270         public function getAssociated( $index ) {
 271                 $this->isMethodValidFor( $index, __METHOD__ );
 272
 273                 if ( $this->isSubject( $index ) ) {
 274                         return $this->getTalk( $index );
 275                 }
 276                 return $this->getSubject( $index );
 277         }
 278
 279         /**
 280          * @param LinkTarget $target
 281          * @return LinkTarget Talk page for $target if it's a subject page, subject page if it's a talk
 282          *   page
 283          * @throws MWException if $target's namespace doesn't have talk pages (e.g., NS_SPECIAL)
 284          */
 285         public function getAssociatedPage( LinkTarget $target ) : LinkTarget {
 286                 if ( $target->getText() === '' ) {
 287                         throw new MWException( 'Can\'t determine talk page associated with relative section link' );
 288                 }
 289
 290                 if ( $target->getInterwiki() !== '' ) {
 291                         throw new MWException( 'Can\'t determine talk page associated with interwiki link' );
 292                 }
 293
 294                 return new TitleValue(
 295                         $this->getAssociated( $target->getNamespace() ), $target->getDBkey() );
 296         }
 297
 298         /**
 299          * Returns whether the specified namespace exists
 300          *
 301          * @param int $index
 302          *
 303          * @return bool
 304          */
 305         public function exists( $index ) {
 306                 $nslist = $this->getCanonicalNamespaces();
 307                 return isset( $nslist[$index] );
 308         }
 309
 310         /**
 311          * Returns whether the specified namespaces are the same namespace
 312          *
 313          * @note It's possible that in the future we may start using something
 314          * other than just namespace indexes. Under that circumstance making use
 315          * of this function rather than directly doing comparison will make
 316          * sure that code will not potentially break.
 317          *
 318          * @param int $ns1 The first namespace index
 319          * @param int $ns2 The second namespace index
 320          *
 321          * @return bool
 322          */
 323         public function equals( $ns1, $ns2 ) {
 324                 return $ns1 == $ns2;
 325         }
 326
 327         /**
 328          * Returns whether the specified namespaces share the same subject.
 329          * eg: NS_USER and NS_USER wil return true, as well
 330          *     NS_USER and NS_USER_TALK will return true.
 331          *
 332          * @param int $ns1 The first namespace index
 333          * @param int $ns2 The second namespace index
 334          *
 335          * @return bool
 336          */
 337         public function subjectEquals( $ns1, $ns2 ) {
 338                 return $this->getSubject( $ns1 ) == $this->getSubject( $ns2 );
 339         }
 340
 341         /**
 342          * Returns array of all defined namespaces with their canonical
 343          * (English) names.
 344          *
 345          * @return string[]
 346          */
 347         public function getCanonicalNamespaces() {
 348                 if ( $this->canonicalNamespaces === null ) {
 349                         $this->canonicalNamespaces =
 350                                 [ NS_MAIN => '' ] + $this->options->get( 'CanonicalNamespaceNames' );
 351                         $this->canonicalNamespaces +=
 352                                 ExtensionRegistry::getInstance()->getAttribute( 'ExtensionNamespaces' );
 353                         if ( is_array( $this->options->get( 'ExtraNamespaces' ) ) ) {
 354                                 $this->canonicalNamespaces += $this->options->get( 'ExtraNamespaces' );
 355                         }
 356                         Hooks::run( 'CanonicalNamespaces', [ &$this->canonicalNamespaces ] );
 357                 }
 358                 return $this->canonicalNamespaces;
 359         }
 360
 361         /**
 362          * Returns the canonical (English) name for a given index
 363          *
 364          * @param int $index Namespace index
 365          * @return string|bool If no canonical definition.
 366          */
 367         public function getCanonicalName( $index ) {
 368                 $nslist = $this->getCanonicalNamespaces();
 369                 return $nslist[$index] ?? false;
 370         }
 371
 372         /**
 373          * Returns the index for a given canonical name, or NULL
 374          * The input *must* be converted to lower case first
 375          *
 376          * @param string $name Namespace name
 377          * @return int|null
 378          */
 379         public function getCanonicalIndex( $name ) {
 380                 if ( $this->namespaceIndexes === false ) {
 381                         $this->namespaceIndexes = [];
 382                         foreach ( $this->getCanonicalNamespaces() as $i => $text ) {
 383                                 $this->namespaceIndexes[strtolower( $text )] = $i;
 384                         }
 385                 }
 386                 if ( array_key_exists( $name, $this->namespaceIndexes ) ) {
 387                         return $this->namespaceIndexes[$name];
 388                 } else {
 389                         return null;
 390                 }
 391         }
 392
 393         /**
 394          * Returns an array of the namespaces (by integer id) that exist on the wiki. Used primarily by
 395          * the API in help documentation. The array is sorted numerically and omits negative namespaces.
 396          * @return array
 397          */
 398         public function getValidNamespaces() {
 399                 if ( is_null( $this->validNamespaces ) ) {
 400                         $this->validNamespaces = [];
 401                         foreach ( array_keys( $this->getCanonicalNamespaces() ) as $ns ) {
 402                                 if ( $ns >= 0 ) {
 403                                         $this->validNamespaces[] = $ns;
 404                                 }
 405                         }
 406                         // T109137: sort numerically
 407                         sort( $this->validNamespaces, SORT_NUMERIC );
 408                 }
 409
 410                 return $this->validNamespaces;
 411         }
 412
 413         /*
 414
 415         /**
 416          * Does this namespace ever have a talk namespace?
 417          *
 418          * @param int $index Namespace ID
 419          * @return bool True if this namespace either is or has a corresponding talk namespace.
 420          */
 421         public function hasTalkNamespace( $index ) {
 422                 return $index >= NS_MAIN;
 423         }
 424
 425         /**
 426          * Does this namespace contain content, for the purposes of calculating
 427          * statistics, etc?
 428          *
 429          * @param int $index Index to check
 430          * @return bool
 431          */
 432         public function isContent( $index ) {
 433                 return $index == NS_MAIN || in_array( $index, $this->options->get( 'ContentNamespaces' ) );
 434         }
 435
 436         /**
 437          * Might pages in this namespace require the use of the Signature button on
 438          * the edit toolbar?
 439          *
 440          * @param int $index Index to check
 441          * @return bool
 442          */
 443         public function wantSignatures( $index ) {
 444                 return $this->isTalk( $index ) ||
 445                         in_array( $index, $this->options->get( 'ExtraSignatureNamespaces' ) );
 446         }
 447
 448         /**
 449          * Can pages in a namespace be watched?
 450          *
 451          * @param int $index
 452          * @return bool
 453          */
 454         public function isWatchable( $index ) {
 455                 return $index >= NS_MAIN;
 456         }
 457
 458         /**
 459          * Does the namespace allow subpages?
 460          *
 461          * @param int $index Index to check
 462          * @return bool
 463          */
 464         public function hasSubpages( $index ) {
 465                 return !empty( $this->options->get( 'NamespacesWithSubpages' )[$index] );
 466         }
 467
 468         /**
 469          * Get a list of all namespace indices which are considered to contain content
 470          * @return array Array of namespace indices
 471          */
 472         public function getContentNamespaces() {
 473                 $contentNamespaces = $this->options->get( 'ContentNamespaces' );
 474                 if ( !is_array( $contentNamespaces ) || $contentNamespaces === [] ) {
 475                         return [ NS_MAIN ];
 476                 } elseif ( !in_array( NS_MAIN, $contentNamespaces ) ) {
 477                         // always force NS_MAIN to be part of array (to match the algorithm used by isContent)
 478                         return array_merge( [ NS_MAIN ], $contentNamespaces );
 479                 } else {
 480                         return $contentNamespaces;
 481                 }
 482         }
 483
 484         /**
 485          * List all namespace indices which are considered subject, aka not a talk
 486          * or special namespace. See also NamespaceInfo::isSubject
 487          *
 488          * @return array Array of namespace indices
 489          */
 490         public function getSubjectNamespaces() {
 491                 return array_filter(
 492                         $this->getValidNamespaces(),
 493                         [ $this, 'isSubject' ]
 494                 );
 495         }
 496
 497         /**
 498          * List all namespace indices which are considered talks, aka not a subject
 499          * or special namespace. See also NamespaceInfo::isTalk
 500          *
 501          * @return array Array of namespace indices
 502          */
 503         public function getTalkNamespaces() {
 504                 return array_filter(
 505                         $this->getValidNamespaces(),
 506                         [ $this, 'isTalk' ]
 507                 );
 508         }
 509
 510         /**
 511          * Is the namespace first-letter capitalized?
 512          *
 513          * @param int $index Index to check
 514          * @return bool
 515          */
 516         public function isCapitalized( $index ) {
 517                 // Turn NS_MEDIA into NS_FILE
 518                 $index = $index === NS_MEDIA ? NS_FILE : $index;
 519
 520                 // Make sure to get the subject of our namespace
 521                 $index = $this->getSubject( $index );
 522
 523                 // Some namespaces are special and should always be upper case
 524                 if ( in_array( $index, $this->alwaysCapitalizedNamespaces ) ) {
 525                         return true;
 526                 }
 527                 $overrides = $this->options->get( 'CapitalLinkOverrides' );
 528                 if ( isset( $overrides[$index] ) ) {
 529                         // CapitalLinkOverrides is explicitly set
 530                         return $overrides[$index];
 531                 }
 532                 // Default to the global setting
 533                 return $this->options->get( 'CapitalLinks' );
 534         }
 535
 536         /**
 537          * Does the namespace (potentially) have different aliases for different
 538          * genders. Not all languages make a distinction here.
 539          *
 540          * @param int $index Index to check
 541          * @return bool
 542          */
 543         public function hasGenderDistinction( $index ) {
 544                 return $index == NS_USER || $index == NS_USER_TALK;
 545         }
 546
 547         /**
 548          * It is not possible to use pages from this namespace as template?
 549          *
 550          * @param int $index Index to check
 551          * @return bool
 552          */
 553         public function isNonincludable( $index ) {
 554                 $namespaces = $this->options->get( 'NonincludableNamespaces' );
 555                 return $namespaces && in_array( $index, $namespaces );
 556         }
 557
 558         /**
 559          * Get the default content model for a namespace
 560          * This does not mean that all pages in that namespace have the model
 561          *
 562          * @note To determine the default model for a new page's main slot, or any slot in general,
 563          * use SlotRoleHandler::getDefaultModel() together with SlotRoleRegistry::getRoleHandler().
 564          *
 565          * @param int $index Index to check
 566          * @return null|string Default model name for the given namespace, if set
 567          */
 568         public function getNamespaceContentModel( $index ) {
 569                 return $this->options->get( 'NamespaceContentModels' )[$index] ?? null;
 570         }
 571
 572         /**
 573          * Determine which restriction levels it makes sense to use in a namespace,
 574          * optionally filtered by a user's rights.
 575          *
 576          * @deprecated since 1.34 User PermissionManager::getNamespaceRestrictionLevels instead.
 577          * @param int $index Index to check
 578          * @param User|null $user User to check
 579          * @return array
 580          */
 581         public function getRestrictionLevels( $index, User $user = null ) {
 582                 // PermissionManager is not injected because adding an explicit dependency
 583                 // breaks MW installer by adding a dependency chain on the database before
 584                 // it was set up. Also, the method is deprecated and will be soon removed.
 585                 return MediaWikiServices::getInstance()
 586                         ->getPermissionManager()
 587                         ->getNamespaceRestrictionLevels( $index, $user );
 588         }
 589
 590         /**
 591          * Returns the link type to be used for categories.
 592          *
 593          * This determines which section of a category page titles
 594          * in the namespace will appear within.
 595          *
 596          * @param int $index Namespace index
 597          * @return string One of 'subcat', 'file', 'page'
 598          */
 599         public function getCategoryLinkType( $index ) {
 600                 $this->isMethodValidFor( $index, __METHOD__ );
 601
 602                 if ( $index == NS_CATEGORY ) {
 603                         return 'subcat';
 604                 } elseif ( $index == NS_FILE ) {
 605                         return 'file';
 606                 } else {
 607                         return 'page';
 608                 }
 609         }
 610
 611         /**
 612          * Retrieve the indexes for the namespaces defined by core.
 613          *
 614          * @since 1.34
 615          *
 616          * @return int[]
 617          */
 618         public static function getCommonNamespaces() {
 619                 return array_keys( self::$canonicalNames );
 620         }
 621 }