includes/title/MediaWikiTitleCodec.php

   1 <?php
   2 /**
   3  * A codec for MediaWiki page titles.
   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  * @author Daniel Kinzler
  22  */
  23
  24 namespace MediaWiki\Title;
  25
  26 use InvalidArgumentException;
  27 use LogicException;
  28 use MediaWiki\Cache\GenderCache;
  29 use MediaWiki\Interwiki\InterwikiLookup;
  30 use MediaWiki\Language\Language;
  31 use MediaWiki\Linker\LinkTarget;
  32 use MediaWiki\Message\Message;
  33 use MediaWiki\Page\PageReference;
  34 use MediaWiki\Parser\Sanitizer;
  35 use Wikimedia\IPUtils;
  36
  37 /**
  38  * A codec for MediaWiki page titles.
  39  *
  40  * @note Normalization and validation is applied while parsing, not when formatting.
  41  * It's possible to construct a TitleValue with an invalid title, and use MediaWikiTitleCodec
  42  * to generate an (invalid) title string from it. TitleValues should be constructed only
  43  * via parseTitle() or from a (semi)trusted source, such as the database.
  44  *
  45  * @see https://www.mediawiki.org/wiki/Requests_for_comment/TitleValue
  46  * @since 1.23
  47  */
  48 class MediaWikiTitleCodec implements TitleFormatter, TitleParser {
  49         protected Language $language;
  50         protected GenderCache $genderCache;
  51         /** @var string[] */
  52         protected array $localInterwikis;
  53         protected InterwikiLookup $interwikiLookup;
  54         protected NamespaceInfo $nsInfo;
  55
  56         /**
  57          * The code here can throw MalformedTitleException, which cannot be created in
  58          * unit tests (see T281935). Until that changes, we use this helper callback
  59          * that can be overridden in unit tests to return a mock instead.
  60          *
  61          * @var callable
  62          */
  63         private $createMalformedTitleException;
  64
  65         /**
  66          * @param Language $language The language object to use for localizing namespace names,
  67          *   capitalization, etc.
  68          * @param GenderCache $genderCache The gender cache for generating gendered namespace names
  69          * @param string[]|string $localInterwikis
  70          * @param InterwikiLookup $interwikiLookup
  71          * @param NamespaceInfo $nsInfo
  72          */
  73         public function __construct(
  74                 Language $language,
  75                 GenderCache $genderCache,
  76                 $localInterwikis,
  77                 InterwikiLookup $interwikiLookup,
  78                 NamespaceInfo $nsInfo
  79         ) {
  80                 $this->language = $language;
  81                 $this->genderCache = $genderCache;
  82                 $this->localInterwikis = (array)$localInterwikis;
  83                 $this->interwikiLookup = $interwikiLookup;
  84                 $this->nsInfo = $nsInfo;
  85
  86                 // Default callback is to return a real MalformedTitleException,
  87                 // callback signature matches constructor
  88                 $this->createMalformedTitleException = static function (
  89                         $errorMessage,
  90                         $titleText = null,
  91                         $errorMessageParameters = []
  92                 ): MalformedTitleException {
  93                         return new MalformedTitleException( $errorMessage, $titleText, $errorMessageParameters );
  94                 };
  95         }
  96
  97         /**
  98          * @internal
  99          * @param callable $callback
 100          */
 101         public function overrideCreateMalformedTitleExceptionCallback( callable $callback ) {
 102                 // @codeCoverageIgnoreStart
 103                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 104                         throw new LogicException( __METHOD__ . ' can only be used in tests' );
 105                 }
 106                 // @codeCoverageIgnoreEnd
 107                 $this->createMalformedTitleException = $callback;
 108         }
 109
 110         /**
 111          * @see TitleFormatter::getNamespaceName()
 112          *
 113          * @param int $namespace
 114          * @param string $text
 115          *
 116          * @throws InvalidArgumentException If the namespace is invalid
 117          * @return string Namespace name with underscores (not spaces), e.g. 'User_talk'
 118          */
 119         public function getNamespaceName( $namespace, $text ) {
 120                 if ( $this->language->needsGenderDistinction() &&
 121                         $this->nsInfo->hasGenderDistinction( $namespace )
 122                 ) {
 123                         // NOTE: we are assuming here that the title text is a user name!
 124                         $gender = $this->genderCache->getGenderOf( $text, __METHOD__ );
 125                         $name = $this->language->getGenderNsText( $namespace, $gender );
 126                 } else {
 127                         $name = $this->language->getNsText( $namespace );
 128                 }
 129
 130                 if ( $name === false ) {
 131                         throw new InvalidArgumentException( 'Unknown namespace ID: ' . $namespace );
 132                 }
 133
 134                 return $name;
 135         }
 136
 137         /**
 138          * @see TitleFormatter::formatTitle()
 139          *
 140          * @param int|false $namespace The namespace ID (or false, if the namespace should be ignored)
 141          * @param string $text The page title. Should be valid. Only minimal normalization is applied.
 142          *        Underscores will be replaced.
 143          * @param string $fragment The fragment name (may be empty).
 144          * @param string $interwiki The interwiki name (may be empty).
 145          *
 146          * @throws InvalidArgumentException If the namespace is invalid
 147          * @return string
 148          */
 149         public function formatTitle( $namespace, $text, $fragment = '', $interwiki = '' ) {
 150                 $out = '';
 151                 if ( $interwiki !== '' ) {
 152                         $out = $interwiki . ':';
 153                 }
 154
 155                 if ( $namespace != 0 ) {
 156                         try {
 157                                 $nsName = $this->getNamespaceName( $namespace, $text );
 158                         } catch ( InvalidArgumentException $e ) {
 159                                 // See T165149. Awkward, but better than erroneously linking to the main namespace.
 160                                 $nsName = $this->language->getNsText( NS_SPECIAL ) . ":Badtitle/NS{$namespace}";
 161                         }
 162
 163                         $out .= $nsName . ':';
 164                 }
 165                 $out .= $text;
 166
 167                 if ( $fragment !== '' ) {
 168                         $out .= '#' . $fragment;
 169                 }
 170
 171                 $out = str_replace( '_', ' ', $out );
 172
 173                 return $out;
 174         }
 175
 176         /**
 177          * Parses the given text and constructs a TitleValue.
 178          *
 179          * @param string $text The text to parse
 180          * @param int $defaultNamespace Namespace to assume by default (usually NS_MAIN)
 181          *
 182          * @throws MalformedTitleException
 183          * @return TitleValue
 184          */
 185         public function parseTitle( $text, $defaultNamespace = NS_MAIN ) {
 186                 // Convert things like &eacute; &#257; or &#x3017; into normalized (T16952) text
 187                 $filteredText = Sanitizer::decodeCharReferencesAndNormalize( $text );
 188
 189                 // NOTE: this is an ugly kludge that allows this class to share the
 190                 // code for parsing with the old Title class. The parser code should
 191                 // be refactored to avoid this.
 192                 $parts = $this->splitTitleString( $filteredText, $defaultNamespace );
 193
 194                 return new TitleValue(
 195                         $parts['namespace'],
 196                         $parts['dbkey'],
 197                         $parts['fragment'],
 198                         $parts['interwiki']
 199                 );
 200         }
 201
 202         /**
 203          * Given a namespace and title, return a TitleValue if valid, or null if invalid.
 204          *
 205          * @param int $namespace
 206          * @param string $text
 207          * @param string $fragment
 208          * @param string $interwiki
 209          *
 210          * @return TitleValue|null
 211          */
 212         public function makeTitleValueSafe( $namespace, $text, $fragment = '', $interwiki = '' ) {
 213                 if ( !$this->nsInfo->exists( $namespace ) ) {
 214                         return null;
 215                 }
 216
 217                 $canonicalNs = $this->nsInfo->getCanonicalName( $namespace );
 218                 $fullText = $canonicalNs == '' ? $text : "$canonicalNs:$text";
 219                 if ( strval( $interwiki ) != '' ) {
 220                         $fullText = "$interwiki:$fullText";
 221                 }
 222                 if ( strval( $fragment ) != '' ) {
 223                         $fullText .= '#' . $fragment;
 224                 }
 225
 226                 try {
 227                         $parts = $this->splitTitleString( $fullText );
 228                 } catch ( MalformedTitleException $e ) {
 229                         return null;
 230                 }
 231
 232                 return new TitleValue(
 233                         $parts['namespace'], $parts['dbkey'], $parts['fragment'], $parts['interwiki'] );
 234         }
 235
 236         /**
 237          * @see TitleFormatter::getText()
 238          *
 239          * @param LinkTarget|PageReference $title
 240          *
 241          * @return string
 242          */
 243         public function getText( $title ) {
 244                 if ( $title instanceof LinkTarget ) {
 245                         return $title->getText();
 246                 } elseif ( $title instanceof PageReference ) {
 247                         return strtr( $title->getDBKey(), '_', ' ' );
 248                 } else {
 249                         throw new InvalidArgumentException( '$title has invalid type: ' . get_class( $title ) );
 250                 }
 251         }
 252
 253         /**
 254          * @see TitleFormatter::getText()
 255          *
 256          * @param LinkTarget|PageReference $title
 257          *
 258          * @return string
 259          * @suppress PhanUndeclaredProperty
 260          */
 261         public function getPrefixedText( $title ) {
 262                 if ( $title instanceof LinkTarget ) {
 263                         if ( !isset( $title->prefixedText ) ) {
 264                                 $title->prefixedText = $this->formatTitle(
 265                                         $title->getNamespace(),
 266                                         $title->getText(),
 267                                         '',
 268                                         $title->getInterwiki()
 269                                 );
 270                         }
 271                         return $title->prefixedText;
 272                 } elseif ( $title instanceof PageReference ) {
 273                         $title->assertWiki( PageReference::LOCAL );
 274                         return $this->formatTitle(
 275                                 $title->getNamespace(),
 276                                 $this->getText( $title )
 277                         );
 278                 } else {
 279                         throw new InvalidArgumentException( '$title has invalid type: ' . get_class( $title ) );
 280                 }
 281         }
 282
 283         /**
 284          * @since 1.27
 285          * @see TitleFormatter::getPrefixedDBkey()
 286          * @param LinkTarget|PageReference $target
 287          * @return string
 288          */
 289         public function getPrefixedDBkey( $target ) {
 290                 if ( $target instanceof LinkTarget ) {
 291                         return strtr( $this->formatTitle(
 292                                 $target->getNamespace(),
 293                                 $target->getDBkey(),
 294                                 '',
 295                                 $target->getInterwiki()
 296                         ), ' ', '_' );
 297                 } elseif ( $target instanceof PageReference ) {
 298                         $target->assertWiki( PageReference::LOCAL );
 299                         return strtr( $this->formatTitle(
 300                                 $target->getNamespace(),
 301                                 $target->getDBkey()
 302                         ), ' ', '_' );
 303                 } else {
 304                         throw new InvalidArgumentException( '$title has invalid type: ' . get_class( $target ) );
 305                 }
 306         }
 307
 308         /**
 309          * @see TitleFormatter::getText()
 310          *
 311          * @param LinkTarget|PageReference $title
 312          *
 313          * @return string
 314          */
 315         public function getFullText( $title ) {
 316                 if ( $title instanceof LinkTarget ) {
 317                         return $this->formatTitle(
 318                                 $title->getNamespace(),
 319                                 $title->getText(),
 320                                 $title->getFragment(),
 321                                 $title->getInterwiki()
 322                         );
 323                 } elseif ( $title instanceof PageReference ) {
 324                         $title->assertWiki( PageReference::LOCAL );
 325                         return $this->formatTitle(
 326                                 $title->getNamespace(),
 327                                 $this->getText( $title )
 328                         );
 329                 } else {
 330                         throw new InvalidArgumentException( '$title has invalid type: ' . get_class( $title ) );
 331                 }
 332         }
 333
 334         /**
 335          * Validates, normalizes and splits a title string.
 336          * This is the "source of truth" for title validity.
 337          *
 338          * This function removes illegal characters, splits off the interwiki and
 339          * namespace prefixes, sets the other forms, and canonicalizes
 340          * everything.
 341          *
 342          * @todo this method is only exposed as a temporary measure to ease refactoring.
 343          * It was copied with minimal changes from Title::secureAndSplit().
 344          *
 345          * @todo This method should be split up and an appropriate interface
 346          * defined for use by the Title class.
 347          *
 348          * @param string $text
 349          * @param int $defaultNamespace
 350          *
 351          * @internal
 352          * @throws MalformedTitleException If $text is not a valid title string.
 353          * @return array A map with the fields 'interwiki', 'fragment', 'namespace', and 'dbkey'.
 354          */
 355         public function splitTitleString( $text, $defaultNamespace = NS_MAIN ) {
 356                 $dbkey = str_replace( ' ', '_', $text );
 357
 358                 # Initialisation
 359                 $parts = [
 360                         'interwiki' => '',
 361                         'local_interwiki' => false,
 362                         'fragment' => '',
 363                         'namespace' => (int)$defaultNamespace,
 364                         'dbkey' => $dbkey,
 365                 ];
 366
 367                 # Strip Unicode bidi override characters.
 368                 # Sometimes they slip into cut-n-pasted page titles, where the
 369                 # override chars get included in list displays.
 370                 $dbkey = preg_replace( '/[\x{200E}\x{200F}\x{202A}-\x{202E}]+/u', '', $dbkey );
 371
 372                 if ( $dbkey === null ) {
 373                         # Regex had an error. Most likely this is caused by invalid UTF-8
 374                         $exception = ( $this->createMalformedTitleException )( 'title-invalid-utf8', $text );
 375                         throw $exception;
 376                 }
 377
 378                 # Clean up whitespace
 379                 $dbkey = preg_replace(
 380                         '/[ _\xA0\x{1680}\x{180E}\x{2000}-\x{200A}\x{2028}\x{2029}\x{202F}\x{205F}\x{3000}]+/u',
 381                         '_',
 382                         $dbkey
 383                 );
 384                 $dbkey = trim( $dbkey, '_' );
 385
 386                 if ( strpos( $dbkey, \UtfNormal\Constants::UTF8_REPLACEMENT ) !== false ) {
 387                         # Contained illegal UTF-8 sequences or forbidden Unicode chars.
 388                         $exception = ( $this->createMalformedTitleException )( 'title-invalid-utf8', $text );
 389                         throw $exception;
 390                 }
 391
 392                 $parts['dbkey'] = $dbkey;
 393
 394                 # Initial colon indicates main namespace rather than specified default
 395                 # but should not create invalid {ns,title} pairs such as {0,Project:Foo}
 396                 if ( $dbkey !== '' && $dbkey[0] == ':' ) {
 397                         $parts['namespace'] = NS_MAIN;
 398                         $dbkey = substr( $dbkey, 1 ); # remove the colon but continue processing
 399                         $dbkey = trim( $dbkey, '_' ); # remove any subsequent whitespace
 400                 }
 401
 402                 if ( $dbkey == '' ) {
 403                         $exception = ( $this->createMalformedTitleException )( 'title-invalid-empty', $text );
 404                         throw $exception;
 405                 }
 406
 407                 # Namespace or interwiki prefix
 408                 $prefixRegexp = "/^(.+?)_*:_*(.*)$/S";
 409                 do {
 410                         $m = [];
 411                         if ( preg_match( $prefixRegexp, $dbkey, $m ) ) {
 412                                 $p = $m[1];
 413                                 $ns = $this->language->getNsIndex( $p );
 414                                 if ( $ns !== false ) {
 415                                         # Ordinary namespace
 416                                         $dbkey = $m[2];
 417                                         $parts['namespace'] = $ns;
 418                                         # For Talk:X pages, check if X has a "namespace" prefix
 419                                         if ( $ns === NS_TALK && preg_match( $prefixRegexp, $dbkey, $x ) ) {
 420                                                 if ( $this->language->getNsIndex( $x[1] ) ) {
 421                                                         # Disallow Talk:File:x type titles...
 422                                                         $exception = ( $this->createMalformedTitleException )(
 423                                                                 'title-invalid-talk-namespace',
 424                                                                 $text
 425                                                         );
 426                                                         throw $exception;
 427                                                 } elseif ( $this->interwikiLookup->isValidInterwiki( $x[1] ) ) {
 428                                                         # Disallow Talk:Interwiki:x type titles...
 429                                                         $exception = ( $this->createMalformedTitleException )(
 430                                                                 'title-invalid-talk-interwiki',
 431                                                                 $text
 432                                                         );
 433                                                         throw $exception;
 434                                                 }
 435                                         }
 436                                 } elseif ( $this->interwikiLookup->isValidInterwiki( $p ) ) {
 437                                         # Interwiki link
 438                                         $dbkey = $m[2];
 439                                         $parts['interwiki'] = $this->language->lc( $p );
 440
 441                                         # Redundant interwiki prefix to the local wiki
 442                                         foreach ( $this->localInterwikis as $localIW ) {
 443                                                 if ( strcasecmp( $parts['interwiki'], $localIW ) == 0 ) {
 444                                                         if ( $dbkey == '' ) {
 445                                                                 # Empty self-links should point to the Main Page, to ensure
 446                                                                 # compatibility with cross-wiki transclusions and the like.
 447                                                                 $mainPage = Title::newMainPage();
 448                                                                 return [
 449                                                                         'interwiki' => $mainPage->getInterwiki(),
 450                                                                         'local_interwiki' => true,
 451                                                                         'fragment' => $mainPage->getFragment(),
 452                                                                         'namespace' => $mainPage->getNamespace(),
 453                                                                         'dbkey' => $mainPage->getDBkey(),
 454                                                                 ];
 455                                                         }
 456                                                         $parts['interwiki'] = '';
 457                                                         # local interwikis should behave like initial-colon links
 458                                                         $parts['local_interwiki'] = true;
 459
 460                                                         # Do another namespace split...
 461                                                         continue 2;
 462                                                 }
 463                                         }
 464
 465                                         # If there's an initial colon after the interwiki, that also
 466                                         # resets the default namespace
 467                                         if ( $dbkey !== '' && $dbkey[0] == ':' ) {
 468                                                 $parts['namespace'] = NS_MAIN;
 469                                                 $dbkey = substr( $dbkey, 1 );
 470                                                 $dbkey = trim( $dbkey, '_' );
 471                                         }
 472                                 }
 473                                 # If there's no recognized interwiki or namespace,
 474                                 # then let the colon expression be part of the title.
 475                         }
 476                         break;
 477                 } while ( true );
 478
 479                 $fragment = strstr( $dbkey, '#' );
 480                 if ( $fragment !== false ) {
 481                         $parts['fragment'] = str_replace( '_', ' ', substr( $fragment, 1 ) );
 482                         $dbkey = substr( $dbkey, 0, strlen( $dbkey ) - strlen( $fragment ) );
 483                         # remove whitespace again: prevents "Foo_bar_#"
 484                         # becoming "Foo_bar_"
 485                         $dbkey = rtrim( $dbkey, "_" );
 486                 }
 487
 488                 # Reject illegal characters.
 489                 $rxTc = self::getTitleInvalidRegex();
 490                 $matches = [];
 491                 if ( preg_match( $rxTc, $dbkey, $matches ) ) {
 492                         $exception = ( $this->createMalformedTitleException )( 'title-invalid-characters', $text, [ $matches[0] ] );
 493                         throw $exception;
 494                 }
 495
 496                 # Pages with "/./" or "/../" appearing in the URLs will often be un-
 497                 # reachable due to the way web browsers deal with 'relative' URLs.
 498                 # Also, they conflict with subpage syntax.  Forbid them explicitly.
 499                 if (
 500                         str_contains( $dbkey, '.' ) &&
 501                         (
 502                                 $dbkey === '.' || $dbkey === '..' ||
 503                                 str_starts_with( $dbkey, './' ) ||
 504                                 str_starts_with( $dbkey, '../' ) ||
 505                                 str_contains( $dbkey, '/./' ) ||
 506                                 str_contains( $dbkey, '/../' ) ||
 507                                 str_ends_with( $dbkey, '/.' ) ||
 508                                 str_ends_with( $dbkey, '/..' )
 509                         )
 510                 ) {
 511                         $exception = ( $this->createMalformedTitleException )( 'title-invalid-relative', $text );
 512                         throw $exception;
 513                 }
 514
 515                 # Magic tilde sequences? Nu-uh!
 516                 if ( strpos( $dbkey, '~~~' ) !== false ) {
 517                         $exception = ( $this->createMalformedTitleException )( 'title-invalid-magic-tilde', $text );
 518                         throw $exception;
 519                 }
 520
 521                 # Limit the size of titles to 255 bytes. This is typically the size of the
 522                 # underlying database field. We make an exception for special pages, which
 523                 # don't need to be stored in the database, and may edge over 255 bytes due
 524                 # to subpage syntax for long titles, e.g. [[Special:Block/Long name]]
 525                 $maxLength = ( $parts['namespace'] !== NS_SPECIAL ) ? 255 : 512;
 526                 if ( strlen( $dbkey ) > $maxLength ) {
 527                         $exception = ( $this->createMalformedTitleException )(
 528                                 'title-invalid-too-long',
 529                                 $text,
 530                                 [ Message::numParam( $maxLength ), Message::numParam( strlen( $dbkey ) ) ]
 531                         );
 532                         throw $exception;
 533                 }
 534
 535                 # Normally, all wiki links are forced to have an initial capital letter so [[foo]]
 536                 # and [[Foo]] point to the same place.  Don't force it for interwikis, since the
 537                 # other site might be case-sensitive.
 538                 if ( $parts['interwiki'] === '' && $this->nsInfo->isCapitalized( $parts['namespace'] ) ) {
 539                         $dbkey = $this->language->ucfirst( $dbkey );
 540                 }
 541
 542                 # Can't make a link to a namespace alone... "empty" local links can only be
 543                 # self-links with a fragment identifier.
 544                 if ( $dbkey == '' && $parts['interwiki'] === '' && $parts['namespace'] !== NS_MAIN ) {
 545                         $exception = ( $this->createMalformedTitleException )( 'title-invalid-empty', $text );
 546                         throw $exception;
 547                 }
 548
 549                 // Allow IPv6 usernames to start with '::' by canonicalizing IPv6 titles.
 550                 // IP names are not allowed for accounts, and can only be referring to
 551                 // edits from the IP. Given '::' abbreviations and caps/lowercaps,
 552                 // there are numerous ways to present the same IP. Having sp:contribs scan
 553                 // them all is silly and having some show the edits and others not is
 554                 // inconsistent. Same for talk/userpages. Keep them normalized instead.
 555                 if ( $dbkey !== '' && ( $parts['namespace'] === NS_USER || $parts['namespace'] === NS_USER_TALK ) ) {
 556                         $dbkey = IPUtils::sanitizeIP( $dbkey );
 557                         // IPUtils::sanitizeIP return null only for bad input
 558                         '@phan-var string $dbkey';
 559                 }
 560
 561                 // Any remaining initial :s are illegal.
 562                 if ( $dbkey !== '' && $dbkey[0] == ':' ) {
 563                         $exception = ( $this->createMalformedTitleException )( 'title-invalid-leading-colon', $text );
 564                         throw $exception;
 565                 }
 566
 567                 // Fill fields
 568                 $parts['dbkey'] = $dbkey;
 569
 570                 // Check to ensure that the return value can be used to construct a TitleValue.
 571                 // All issues should in theory be caught above, this is here to enforce consistency.
 572                 try {
 573                         TitleValue::assertValidSpec(
 574                                 $parts['namespace'],
 575                                 $parts['dbkey'],
 576                                 $parts['fragment'],
 577                                 $parts['interwiki']
 578                         );
 579                 } catch ( InvalidArgumentException $ex ) {
 580                         $exception = ( $this->createMalformedTitleException )( 'title-invalid', $text, [ $ex->getMessage() ] );
 581                         throw $exception;
 582                 }
 583
 584                 return $parts;
 585         }
 586
 587         /**
 588          * Returns a simple regex that will match on characters and sequences invalid in titles.
 589          * Note that this doesn't pick up many things that could be wrong with titles, but that
 590          * replacing this regex with something valid will make many titles valid.
 591          * Previously Title::getTitleInvalidRegex()
 592          *
 593          * @return string Regex string
 594          * @since 1.25
 595          */
 596         public static function getTitleInvalidRegex() {
 597                 static $rxTc = false;
 598                 if ( !$rxTc ) {
 599                         # Matching titles will be held as illegal.
 600                         $rxTc = '/' .
 601                                 # Any character not allowed is forbidden...
 602                                 '[^' . Title::legalChars() . ']' .
 603                                 # URL percent encoding sequences interfere with the ability
 604                                 # to round-trip titles -- you can't link to them consistently.
 605                                 '|%[0-9A-Fa-f]{2}' .
 606                                 # XML/HTML character references produce similar issues.
 607                                 '|&[A-Za-z0-9\x80-\xff]+;' .
 608                                 '/S';
 609                 }
 610
 611                 return $rxTc;
 612         }
 613 }
 614
 615 /** @deprecated class alias since 1.41 */
 616 class_alias( MediaWikiTitleCodec::class, 'MediaWikiTitleCodec' );