includes/MWNamespace.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 /**
  24  * This is a utility class with only static functions
  25  * for dealing with namespaces that encodes all the
  26  * "magic" behaviors of them based on index.  The textual
  27  * names of the namespaces are handled by Language.php.
  28  *
  29  * These are synonyms for the names given in the language file
  30  * Users and translators should not change them
  31  */
  32 class MWNamespace {
  33
  34         /**
  35          * These namespaces should always be first-letter capitalized, now and
  36          * forevermore. Historically, they could've probably been lowercased too,
  37          * but some things are just too ingrained now. :)
  38          */
  39         private static $alwaysCapitalizedNamespaces = [ NS_SPECIAL, NS_USER, NS_MEDIAWIKI ];
  40
  41         /** @var string[]|null Canonical namespaces cache */
  42         private static $canonicalNamespaces = null;
  43
  44         /** @var array|false Canonical namespaces index cache */
  45         private static $namespaceIndexes = false;
  46
  47         /** @var int[]|null Valid namespaces cache */
  48         private static $validNamespaces = null;
  49
  50         /**
  51          * Throw an exception when trying to get the subject or talk page
  52          * for a given namespace where it does not make sense.
  53          * Special namespaces are defined in includes/Defines.php and have
  54          * a value below 0 (ex: NS_SPECIAL = -1 , NS_MEDIA = -2)
  55          *
  56          * @param int $index
  57          * @param string $method
  58          *
  59          * @throws MWException
  60          * @return bool
  61          */
  62         private static function isMethodValidFor( $index, $method ) {
  63                 if ( $index < NS_MAIN ) {
  64                         throw new MWException( "$method does not make any sense for given namespace $index" );
  65                 }
  66                 return true;
  67         }
  68
  69         /**
  70          * Clear internal caches
  71          *
  72          * For use in unit testing when namespace configuration is changed.
  73          *
  74          * @since 1.31
  75          */
  76         public static function clearCaches() {
  77                 self::$canonicalNamespaces = null;
  78                 self::$namespaceIndexes = false;
  79                 self::$validNamespaces = null;
  80         }
  81
  82         /**
  83          * Can pages in the given namespace be moved?
  84          *
  85          * @param int $index Namespace index
  86          * @return bool
  87          */
  88         public static function isMovable( $index ) {
  89                 global $wgAllowImageMoving;
  90
  91                 $result = !( $index < NS_MAIN || ( $index == NS_FILE && !$wgAllowImageMoving ) );
  92
  93                 /**
  94                  * @since 1.20
  95                  */
  96                 Hooks::run( 'NamespaceIsMovable', [ $index, &$result ] );
  97
  98                 return $result;
  99         }
 100
 101         /**
 102          * Is the given namespace is a subject (non-talk) namespace?
 103          *
 104          * @param int $index Namespace index
 105          * @return bool
 106          * @since 1.19
 107          */
 108         public static function isSubject( $index ) {
 109                 return !self::isTalk( $index );
 110         }
 111
 112         /**
 113          * Is the given namespace a talk namespace?
 114          *
 115          * @param int $index Namespace index
 116          * @return bool
 117          */
 118         public static function isTalk( $index ) {
 119                 return $index > NS_MAIN
 120                         && $index % 2;
 121         }
 122
 123         /**
 124          * Get the talk namespace index for a given namespace
 125          *
 126          * @param int $index Namespace index
 127          * @return int
 128          */
 129         public static function getTalk( $index ) {
 130                 self::isMethodValidFor( $index, __METHOD__ );
 131                 return self::isTalk( $index )
 132                         ? $index
 133                         : $index + 1;
 134         }
 135
 136         /**
 137          * Get the subject namespace index for a given namespace
 138          * Special namespaces (NS_MEDIA, NS_SPECIAL) are always the subject.
 139          *
 140          * @param int $index Namespace index
 141          * @return int
 142          */
 143         public static function getSubject( $index ) {
 144                 # Handle special namespaces
 145                 if ( $index < NS_MAIN ) {
 146                         return $index;
 147                 }
 148
 149                 return self::isTalk( $index )
 150                         ? $index - 1
 151                         : $index;
 152         }
 153
 154         /**
 155          * Get the associated namespace.
 156          * For talk namespaces, returns the subject (non-talk) namespace
 157          * For subject (non-talk) namespaces, returns the talk namespace
 158          *
 159          * @param int $index Namespace index
 160          * @return int|null If no associated namespace could be found
 161          */
 162         public static function getAssociated( $index ) {
 163                 self::isMethodValidFor( $index, __METHOD__ );
 164
 165                 if ( self::isSubject( $index ) ) {
 166                         return self::getTalk( $index );
 167                 } elseif ( self::isTalk( $index ) ) {
 168                         return self::getSubject( $index );
 169                 } else {
 170                         return null;
 171                 }
 172         }
 173
 174         /**
 175          * Returns whether the specified namespace exists
 176          *
 177          * @param int $index
 178          *
 179          * @return bool
 180          * @since 1.19
 181          */
 182         public static function exists( $index ) {
 183                 $nslist = self::getCanonicalNamespaces();
 184                 return isset( $nslist[$index] );
 185         }
 186
 187         /**
 188          * Returns whether the specified namespaces are the same namespace
 189          *
 190          * @note It's possible that in the future we may start using something
 191          * other than just namespace indexes. Under that circumstance making use
 192          * of this function rather than directly doing comparison will make
 193          * sure that code will not potentially break.
 194          *
 195          * @param int $ns1 The first namespace index
 196          * @param int $ns2 The second namespace index
 197          *
 198          * @return bool
 199          * @since 1.19
 200          */
 201         public static function equals( $ns1, $ns2 ) {
 202                 return $ns1 == $ns2;
 203         }
 204
 205         /**
 206          * Returns whether the specified namespaces share the same subject.
 207          * eg: NS_USER and NS_USER wil return true, as well
 208          *     NS_USER and NS_USER_TALK will return true.
 209          *
 210          * @param int $ns1 The first namespace index
 211          * @param int $ns2 The second namespace index
 212          *
 213          * @return bool
 214          * @since 1.19
 215          */
 216         public static function subjectEquals( $ns1, $ns2 ) {
 217                 return self::getSubject( $ns1 ) == self::getSubject( $ns2 );
 218         }
 219
 220         /**
 221          * Returns array of all defined namespaces with their canonical
 222          * (English) names.
 223          *
 224          * @param bool $rebuild Rebuild namespace list (default = false). Used for testing.
 225          *  Deprecated since 1.31, use self::clearCaches() instead.
 226          *
 227          * @return array
 228          * @since 1.17
 229          */
 230         public static function getCanonicalNamespaces( $rebuild = false ) {
 231                 if ( $rebuild ) {
 232                         self::clearCaches();
 233                 }
 234
 235                 if ( self::$canonicalNamespaces === null ) {
 236                         global $wgExtraNamespaces, $wgCanonicalNamespaceNames;
 237                         self::$canonicalNamespaces = [ NS_MAIN => '' ] + $wgCanonicalNamespaceNames;
 238                         // Add extension namespaces
 239                         self::$canonicalNamespaces +=
 240                                 ExtensionRegistry::getInstance()->getAttribute( 'ExtensionNamespaces' );
 241                         if ( is_array( $wgExtraNamespaces ) ) {
 242                                 self::$canonicalNamespaces += $wgExtraNamespaces;
 243                         }
 244                         Hooks::run( 'CanonicalNamespaces', [ &self::$canonicalNamespaces ] );
 245                 }
 246                 return self::$canonicalNamespaces;
 247         }
 248
 249         /**
 250          * Returns the canonical (English) name for a given index
 251          *
 252          * @param int $index Namespace index
 253          * @return string|bool If no canonical definition.
 254          */
 255         public static function getCanonicalName( $index ) {
 256                 $nslist = self::getCanonicalNamespaces();
 257                 return $nslist[$index] ?? false;
 258         }
 259
 260         /**
 261          * Returns the index for a given canonical name, or NULL
 262          * The input *must* be converted to lower case first
 263          *
 264          * @param string $name Namespace name
 265          * @return int
 266          */
 267         public static function getCanonicalIndex( $name ) {
 268                 if ( self::$namespaceIndexes === false ) {
 269                         self::$namespaceIndexes = [];
 270                         foreach ( self::getCanonicalNamespaces() as $i => $text ) {
 271                                 self::$namespaceIndexes[strtolower( $text )] = $i;
 272                         }
 273                 }
 274                 if ( array_key_exists( $name, self::$namespaceIndexes ) ) {
 275                         return self::$namespaceIndexes[$name];
 276                 } else {
 277                         return null;
 278                 }
 279         }
 280
 281         /**
 282          * Returns an array of the namespaces (by integer id) that exist on the
 283          * wiki. Used primarily by the api in help documentation.
 284          * @return array
 285          */
 286         public static function getValidNamespaces() {
 287                 if ( is_null( self::$validNamespaces ) ) {
 288                         foreach ( array_keys( self::getCanonicalNamespaces() ) as $ns ) {
 289                                 if ( $ns >= 0 ) {
 290                                         self::$validNamespaces[] = $ns;
 291                                 }
 292                         }
 293                         // T109137: sort numerically
 294                         sort( self::$validNamespaces, SORT_NUMERIC );
 295                 }
 296
 297                 return self::$validNamespaces;
 298         }
 299
 300         /**
 301          * Does this namespace ever have a talk namespace?
 302          *
 303          * @deprecated since 1.30, use hasTalkNamespace() instead.
 304          *
 305          * @param int $index Namespace index
 306          * @return bool True if this namespace either is or has a corresponding talk namespace.
 307          */
 308         public static function canTalk( $index ) {
 309                 return self::hasTalkNamespace( $index );
 310         }
 311
 312         /**
 313          * Does this namespace ever have a talk namespace?
 314          *
 315          * @since 1.30
 316          *
 317          * @param int $index Namespace ID
 318          * @return bool True if this namespace either is or has a corresponding talk namespace.
 319          */
 320         public static function hasTalkNamespace( $index ) {
 321                 return $index >= NS_MAIN;
 322         }
 323
 324         /**
 325          * Does this namespace contain content, for the purposes of calculating
 326          * statistics, etc?
 327          *
 328          * @param int $index Index to check
 329          * @return bool
 330          */
 331         public static function isContent( $index ) {
 332                 global $wgContentNamespaces;
 333                 return $index == NS_MAIN || in_array( $index, $wgContentNamespaces );
 334         }
 335
 336         /**
 337          * Might pages in this namespace require the use of the Signature button on
 338          * the edit toolbar?
 339          *
 340          * @param int $index Index to check
 341          * @return bool
 342          */
 343         public static function wantSignatures( $index ) {
 344                 global $wgExtraSignatureNamespaces;
 345                 return self::isTalk( $index ) || in_array( $index, $wgExtraSignatureNamespaces );
 346         }
 347
 348         /**
 349          * Can pages in a namespace be watched?
 350          *
 351          * @param int $index
 352          * @return bool
 353          */
 354         public static function isWatchable( $index ) {
 355                 return $index >= NS_MAIN;
 356         }
 357
 358         /**
 359          * Does the namespace allow subpages?
 360          *
 361          * @param int $index Index to check
 362          * @return bool
 363          */
 364         public static function hasSubpages( $index ) {
 365                 global $wgNamespacesWithSubpages;
 366                 return !empty( $wgNamespacesWithSubpages[$index] );
 367         }
 368
 369         /**
 370          * Get a list of all namespace indices which are considered to contain content
 371          * @return array Array of namespace indices
 372          */
 373         public static function getContentNamespaces() {
 374                 global $wgContentNamespaces;
 375                 if ( !is_array( $wgContentNamespaces ) || $wgContentNamespaces === [] ) {
 376                         return [ NS_MAIN ];
 377                 } elseif ( !in_array( NS_MAIN, $wgContentNamespaces ) ) {
 378                         // always force NS_MAIN to be part of array (to match the algorithm used by isContent)
 379                         return array_merge( [ NS_MAIN ], $wgContentNamespaces );
 380                 } else {
 381                         return $wgContentNamespaces;
 382                 }
 383         }
 384
 385         /**
 386          * List all namespace indices which are considered subject, aka not a talk
 387          * or special namespace. See also MWNamespace::isSubject
 388          *
 389          * @return array Array of namespace indices
 390          */
 391         public static function getSubjectNamespaces() {
 392                 return array_filter(
 393                         self::getValidNamespaces(),
 394                         'MWNamespace::isSubject'
 395                 );
 396         }
 397
 398         /**
 399          * List all namespace indices which are considered talks, aka not a subject
 400          * or special namespace. See also MWNamespace::isTalk
 401          *
 402          * @return array Array of namespace indices
 403          */
 404         public static function getTalkNamespaces() {
 405                 return array_filter(
 406                         self::getValidNamespaces(),
 407                         'MWNamespace::isTalk'
 408                 );
 409         }
 410
 411         /**
 412          * Is the namespace first-letter capitalized?
 413          *
 414          * @param int $index Index to check
 415          * @return bool
 416          */
 417         public static function isCapitalized( $index ) {
 418                 global $wgCapitalLinks, $wgCapitalLinkOverrides;
 419                 // Turn NS_MEDIA into NS_FILE
 420                 $index = $index === NS_MEDIA ? NS_FILE : $index;
 421
 422                 // Make sure to get the subject of our namespace
 423                 $index = self::getSubject( $index );
 424
 425                 // Some namespaces are special and should always be upper case
 426                 if ( in_array( $index, self::$alwaysCapitalizedNamespaces ) ) {
 427                         return true;
 428                 }
 429                 if ( isset( $wgCapitalLinkOverrides[$index] ) ) {
 430                         // $wgCapitalLinkOverrides is explicitly set
 431                         return $wgCapitalLinkOverrides[$index];
 432                 }
 433                 // Default to the global setting
 434                 return $wgCapitalLinks;
 435         }
 436
 437         /**
 438          * Does the namespace (potentially) have different aliases for different
 439          * genders. Not all languages make a distinction here.
 440          *
 441          * @since 1.18
 442          * @param int $index Index to check
 443          * @return bool
 444          */
 445         public static function hasGenderDistinction( $index ) {
 446                 return $index == NS_USER || $index == NS_USER_TALK;
 447         }
 448
 449         /**
 450          * It is not possible to use pages from this namespace as template?
 451          *
 452          * @since 1.20
 453          * @param int $index Index to check
 454          * @return bool
 455          */
 456         public static function isNonincludable( $index ) {
 457                 global $wgNonincludableNamespaces;
 458                 return $wgNonincludableNamespaces && in_array( $index, $wgNonincludableNamespaces );
 459         }
 460
 461         /**
 462          * Get the default content model for a namespace
 463          * This does not mean that all pages in that namespace have the model
 464          *
 465          * @since 1.21
 466          * @param int $index Index to check
 467          * @return null|string Default model name for the given namespace, if set
 468          */
 469         public static function getNamespaceContentModel( $index ) {
 470                 global $wgNamespaceContentModels;
 471                 return $wgNamespaceContentModels[$index] ?? null;
 472         }
 473
 474         /**
 475          * Determine which restriction levels it makes sense to use in a namespace,
 476          * optionally filtered by a user's rights.
 477          *
 478          * @since 1.23
 479          * @param int $index Index to check
 480          * @param User $user User to check
 481          * @return array
 482          */
 483         public static function getRestrictionLevels( $index, User $user = null ) {
 484                 global $wgNamespaceProtection, $wgRestrictionLevels;
 485
 486                 if ( !isset( $wgNamespaceProtection[$index] ) ) {
 487                         // All levels are valid if there's no namespace restriction.
 488                         // But still filter by user, if necessary
 489                         $levels = $wgRestrictionLevels;
 490                         if ( $user ) {
 491                                 $levels = array_values( array_filter( $levels, function ( $level ) use ( $user ) {
 492                                         $right = $level;
 493                                         if ( $right == 'sysop' ) {
 494                                                 $right = 'editprotected'; // BC
 495                                         }
 496                                         if ( $right == 'autoconfirmed' ) {
 497                                                 $right = 'editsemiprotected'; // BC
 498                                         }
 499                                         return ( $right == '' || $user->isAllowed( $right ) );
 500                                 } ) );
 501                         }
 502                         return $levels;
 503                 }
 504
 505                 // First, get the list of groups that can edit this namespace.
 506                 $namespaceGroups = [];
 507                 $combine = 'array_merge';
 508                 foreach ( (array)$wgNamespaceProtection[$index] as $right ) {
 509                         if ( $right == 'sysop' ) {
 510                                 $right = 'editprotected'; // BC
 511                         }
 512                         if ( $right == 'autoconfirmed' ) {
 513                                 $right = 'editsemiprotected'; // BC
 514                         }
 515                         if ( $right != '' ) {
 516                                 $namespaceGroups = call_user_func( $combine, $namespaceGroups,
 517                                         User::getGroupsWithPermission( $right ) );
 518                                 $combine = 'array_intersect';
 519                         }
 520                 }
 521
 522                 // Now, keep only those restriction levels where there is at least one
 523                 // group that can edit the namespace but would be blocked by the
 524                 // restriction.
 525                 $usableLevels = [ '' ];
 526                 foreach ( $wgRestrictionLevels as $level ) {
 527                         $right = $level;
 528                         if ( $right == 'sysop' ) {
 529                                 $right = 'editprotected'; // BC
 530                         }
 531                         if ( $right == 'autoconfirmed' ) {
 532                                 $right = 'editsemiprotected'; // BC
 533                         }
 534                         if ( $right != '' && ( !$user || $user->isAllowed( $right ) ) &&
 535                                 array_diff( $namespaceGroups, User::getGroupsWithPermission( $right ) )
 536                         ) {
 537                                 $usableLevels[] = $level;
 538                         }
 539                 }
 540
 541                 return $usableLevels;
 542         }
 543 }