includes/parser/CoreParserFunctions.php

   1 <?php
   2 /**
   3  * Parser functions provided by MediaWiki core
   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 Parser
  22  */
  23
  24 /**
  25  * Various core parser functions, registered in Parser::firstCallInit()
  26  * @ingroup Parser
  27  */
  28 class CoreParserFunctions {
  29         /**
  30          * @param Parser $parser
  31          * @return void
  32          */
  33         public static function register( $parser ) {
  34                 global $wgAllowDisplayTitle, $wgAllowSlowParserFunctions;
  35
  36                 # Syntax for arguments (see Parser::setFunctionHook):
  37                 #  "name for lookup in localized magic words array",
  38                 #  function callback,
  39                 #  optional Parser::SFH_NO_HASH to omit the hash from calls (e.g. {{int:...}}
  40                 #    instead of {{#int:...}})
  41                 $noHashFunctions = array(
  42                         'ns', 'nse', 'urlencode', 'lcfirst', 'ucfirst', 'lc', 'uc',
  43                         'localurl', 'localurle', 'fullurl', 'fullurle', 'canonicalurl',
  44                         'canonicalurle', 'formatnum', 'grammar', 'gender', 'plural', 'bidi',
  45                         'numberofpages', 'numberofusers', 'numberofactiveusers',
  46                         'numberofarticles', 'numberoffiles', 'numberofadmins',
  47                         'numberingroup', 'numberofedits', 'language',
  48                         'padleft', 'padright', 'anchorencode', 'defaultsort', 'filepath',
  49                         'pagesincategory', 'pagesize', 'protectionlevel',
  50                         'namespacee', 'namespacenumber', 'talkspace', 'talkspacee',
  51                         'subjectspace', 'subjectspacee', 'pagename', 'pagenamee',
  52                         'fullpagename', 'fullpagenamee', 'rootpagename', 'rootpagenamee',
  53                         'basepagename', 'basepagenamee', 'subpagename', 'subpagenamee',
  54                         'talkpagename', 'talkpagenamee', 'subjectpagename',
  55                         'subjectpagenamee', 'pageid', 'revisionid', 'revisionday',
  56                         'revisionday2', 'revisionmonth', 'revisionmonth1', 'revisionyear',
  57                         'revisiontimestamp', 'revisionuser', 'cascadingsources',
  58                 );
  59                 foreach ( $noHashFunctions as $func ) {
  60                         $parser->setFunctionHook( $func, array( __CLASS__, $func ), Parser::SFH_NO_HASH );
  61                 }
  62
  63                 $parser->setFunctionHook(
  64                         'namespace',
  65                         array( __CLASS__, 'mwnamespace' ),
  66                         Parser::SFH_NO_HASH
  67                 );
  68                 $parser->setFunctionHook( 'int', array( __CLASS__, 'intFunction' ), Parser::SFH_NO_HASH );
  69                 $parser->setFunctionHook( 'special', array( __CLASS__, 'special' ) );
  70                 $parser->setFunctionHook( 'speciale', array( __CLASS__, 'speciale' ) );
  71                 $parser->setFunctionHook( 'tag', array( __CLASS__, 'tagObj' ), Parser::SFH_OBJECT_ARGS );
  72                 $parser->setFunctionHook( 'formatdate', array( __CLASS__, 'formatDate' ) );
  73
  74                 if ( $wgAllowDisplayTitle ) {
  75                         $parser->setFunctionHook(
  76                                 'displaytitle',
  77                                 array( __CLASS__, 'displaytitle' ),
  78                                 Parser::SFH_NO_HASH
  79                         );
  80                 }
  81                 if ( $wgAllowSlowParserFunctions ) {
  82                         $parser->setFunctionHook(
  83                                 'pagesinnamespace',
  84                                 array( __CLASS__, 'pagesinnamespace' ),
  85                                 Parser::SFH_NO_HASH
  86                         );
  87                 }
  88         }
  89
  90         /**
  91          * @param Parser $parser
  92          * @param string $part1
  93          * @return array
  94          */
  95         public static function intFunction( $parser, $part1 = '' /*, ... */ ) {
  96                 if ( strval( $part1 ) !== '' ) {
  97                         $args = array_slice( func_get_args(), 2 );
  98                         $message = wfMessage( $part1, $args )
  99                                 ->inLanguage( $parser->getOptions()->getUserLangObj() );
 100                         if ( !$message->exists() ) {
 101                                 // When message does not exists, the message name is surrounded by angle
 102                                 // and can result in a tag, therefore escape the angles
 103                                 return $message->escaped();
 104                         }
 105                         return array( $message->plain(), 'noparse' => false );
 106                 } else {
 107                         return array( 'found' => false );
 108                 }
 109         }
 110
 111         /**
 112          * @param Parser $parser
 113          * @param string $date
 114          * @param string $defaultPref
 115          *
 116          * @return string
 117          */
 118         public static function formatDate( $parser, $date, $defaultPref = null ) {
 119                 $lang = $parser->getFunctionLang();
 120                 $df = DateFormatter::getInstance( $lang );
 121
 122                 $date = trim( $date );
 123
 124                 $pref = $parser->getOptions()->getDateFormat();
 125
 126                 // Specify a different default date format other than the normal default
 127                 // if the user has 'default' for their setting
 128                 if ( $pref == 'default' && $defaultPref ) {
 129                         $pref = $defaultPref;
 130                 }
 131
 132                 $date = $df->reformat( $pref, $date, array( 'match-whole' ) );
 133                 return $date;
 134         }
 135
 136         public static function ns( $parser, $part1 = '' ) {
 137                 global $wgContLang;
 138                 if ( intval( $part1 ) || $part1 == "0" ) {
 139                         $index = intval( $part1 );
 140                 } else {
 141                         $index = $wgContLang->getNsIndex( str_replace( ' ', '_', $part1 ) );
 142                 }
 143                 if ( $index !== false ) {
 144                         return $wgContLang->getFormattedNsText( $index );
 145                 } else {
 146                         return array( 'found' => false );
 147                 }
 148         }
 149
 150         public static function nse( $parser, $part1 = '' ) {
 151                 $ret = self::ns( $parser, $part1 );
 152                 if ( is_string( $ret ) ) {
 153                         $ret = wfUrlencode( str_replace( ' ', '_', $ret ) );
 154                 }
 155                 return $ret;
 156         }
 157
 158         /**
 159          * urlencodes a string according to one of three patterns: (bug 22474)
 160          *
 161          * By default (for HTTP "query" strings), spaces are encoded as '+'.
 162          * Or to encode a value for the HTTP "path", spaces are encoded as '%20'.
 163          * For links to "wiki"s, or similar software, spaces are encoded as '_',
 164          *
 165          * @param Parser $parser
 166          * @param string $s The text to encode.
 167          * @param string $arg (optional): The type of encoding.
 168          * @return string
 169          */
 170         public static function urlencode( $parser, $s = '', $arg = null ) {
 171                 static $magicWords = null;
 172                 if ( is_null( $magicWords ) ) {
 173                         $magicWords = new MagicWordArray( array( 'url_path', 'url_query', 'url_wiki' ) );
 174                 }
 175                 switch ( $magicWords->matchStartToEnd( $arg ) ) {
 176
 177                         // Encode as though it's a wiki page, '_' for ' '.
 178                         case 'url_wiki':
 179                                 $func = 'wfUrlencode';
 180                                 $s = str_replace( ' ', '_', $s );
 181                                 break;
 182
 183                         // Encode for an HTTP Path, '%20' for ' '.
 184                         case 'url_path':
 185                                 $func = 'rawurlencode';
 186                                 break;
 187
 188                         // Encode for HTTP query, '+' for ' '.
 189                         case 'url_query':
 190                         default:
 191                                 $func = 'urlencode';
 192                 }
 193                 // See T105242, where the choice to kill markers and various
 194                 // other options were discussed.
 195                 return $func( $parser->killMarkers( $s ) );
 196         }
 197
 198         public static function lcfirst( $parser, $s = '' ) {
 199                 global $wgContLang;
 200                 return $wgContLang->lcfirst( $s );
 201         }
 202
 203         public static function ucfirst( $parser, $s = '' ) {
 204                 global $wgContLang;
 205                 return $wgContLang->ucfirst( $s );
 206         }
 207
 208         /**
 209          * @param Parser $parser
 210          * @param string $s
 211          * @return string
 212          */
 213         public static function lc( $parser, $s = '' ) {
 214                 global $wgContLang;
 215                 return $parser->markerSkipCallback( $s, array( $wgContLang, 'lc' ) );
 216         }
 217
 218         /**
 219          * @param Parser $parser
 220          * @param string $s
 221          * @return string
 222          */
 223         public static function uc( $parser, $s = '' ) {
 224                 global $wgContLang;
 225                 return $parser->markerSkipCallback( $s, array( $wgContLang, 'uc' ) );
 226         }
 227
 228         public static function localurl( $parser, $s = '', $arg = null ) {
 229                 return self::urlFunction( 'getLocalURL', $s, $arg );
 230         }
 231
 232         public static function localurle( $parser, $s = '', $arg = null ) {
 233                 $temp = self::urlFunction( 'getLocalURL', $s, $arg );
 234                 if ( !is_string( $temp ) ) {
 235                         return $temp;
 236                 } else {
 237                         return htmlspecialchars( $temp );
 238                 }
 239         }
 240
 241         public static function fullurl( $parser, $s = '', $arg = null ) {
 242                 return self::urlFunction( 'getFullURL', $s, $arg );
 243         }
 244
 245         public static function fullurle( $parser, $s = '', $arg = null ) {
 246                 $temp = self::urlFunction( 'getFullURL', $s, $arg );
 247                 if ( !is_string( $temp ) ) {
 248                         return $temp;
 249                 } else {
 250                         return htmlspecialchars( $temp );
 251                 }
 252         }
 253
 254         public static function canonicalurl( $parser, $s = '', $arg = null ) {
 255                 return self::urlFunction( 'getCanonicalURL', $s, $arg );
 256         }
 257
 258         public static function canonicalurle( $parser, $s = '', $arg = null ) {
 259                 $temp = self::urlFunction( 'getCanonicalURL', $s, $arg );
 260                 if ( !is_string( $temp ) ) {
 261                         return $temp;
 262                 } else {
 263                         return htmlspecialchars( $temp );
 264                 }
 265         }
 266
 267         public static function urlFunction( $func, $s = '', $arg = null ) {
 268                 $title = Title::newFromText( $s );
 269                 # Due to order of execution of a lot of bits, the values might be encoded
 270                 # before arriving here; if that's true, then the title can't be created
 271                 # and the variable will fail. If we can't get a decent title from the first
 272                 # attempt, url-decode and try for a second.
 273                 if ( is_null( $title ) ) {
 274                         $title = Title::newFromURL( urldecode( $s ) );
 275                 }
 276                 if ( !is_null( $title ) ) {
 277                         # Convert NS_MEDIA -> NS_FILE
 278                         if ( $title->getNamespace() == NS_MEDIA ) {
 279                                 $title = Title::makeTitle( NS_FILE, $title->getDBkey() );
 280                         }
 281                         if ( !is_null( $arg ) ) {
 282                                 $text = $title->$func( $arg );
 283                         } else {
 284                                 $text = $title->$func();
 285                         }
 286                         return $text;
 287                 } else {
 288                         return array( 'found' => false );
 289                 }
 290         }
 291
 292         /**
 293          * @param Parser $parser
 294          * @param string $num
 295          * @param string $arg
 296          * @return string
 297          */
 298         public static function formatnum( $parser, $num = '', $arg = null ) {
 299                 if ( self::matchAgainstMagicword( 'rawsuffix', $arg ) ) {
 300                         $func = array( $parser->getFunctionLang(), 'parseFormattedNumber' );
 301                 } elseif ( self::matchAgainstMagicword( 'nocommafysuffix', $arg ) ) {
 302                         $func = array( $parser->getFunctionLang(), 'formatNumNoSeparators' );
 303                 } else {
 304                         $func = array( $parser->getFunctionLang(), 'formatNum' );
 305                 }
 306                 return $parser->markerSkipCallback( $num, $func );
 307         }
 308
 309         /**
 310          * @param Parser $parser
 311          * @param string $case
 312          * @param string $word
 313          * @return string
 314          */
 315         public static function grammar( $parser, $case = '', $word = '' ) {
 316                 $word = $parser->killMarkers( $word );
 317                 return $parser->getFunctionLang()->convertGrammar( $word, $case );
 318         }
 319
 320         /**
 321          * @param Parser $parser
 322          * @param string $username
 323          * @return string
 324          */
 325         public static function gender( $parser, $username ) {
 326                 $forms = array_slice( func_get_args(), 2 );
 327
 328                 // Some shortcuts to avoid loading user data unnecessarily
 329                 if ( count( $forms ) === 0 ) {
 330                         return '';
 331                 } elseif ( count( $forms ) === 1 ) {
 332                         return $forms[0];
 333                 }
 334
 335                 $username = trim( $username );
 336
 337                 // default
 338                 $gender = User::getDefaultOption( 'gender' );
 339
 340                 // allow prefix.
 341                 $title = Title::newFromText( $username );
 342
 343                 if ( $title && $title->getNamespace() == NS_USER ) {
 344                         $username = $title->getText();
 345                 }
 346
 347                 // check parameter, or use the ParserOptions if in interface message
 348                 $user = User::newFromName( $username );
 349                 if ( $user ) {
 350                         $gender = GenderCache::singleton()->getGenderOf( $user, __METHOD__ );
 351                 } elseif ( $username === '' && $parser->getOptions()->getInterfaceMessage() ) {
 352                         $gender = GenderCache::singleton()->getGenderOf( $parser->getOptions()->getUser(), __METHOD__ );
 353                 }
 354                 $ret = $parser->getFunctionLang()->gender( $gender, $forms );
 355                 return $ret;
 356         }
 357
 358         /**
 359          * @param Parser $parser
 360          * @param string $text
 361          * @return string
 362          */
 363         public static function plural( $parser, $text = '' ) {
 364                 $forms = array_slice( func_get_args(), 2 );
 365                 $text = $parser->getFunctionLang()->parseFormattedNumber( $text );
 366                 settype( $text, ctype_digit( $text ) ? 'int' : 'float' );
 367                 return $parser->getFunctionLang()->convertPlural( $text, $forms );
 368         }
 369
 370         /**
 371          * @param Parser $parser
 372          * @param string $text
 373          * @return string
 374          */
 375         public static function bidi( $parser, $text = '' ) {
 376                 return $parser->getFunctionLang()->embedBidi( $text );
 377         }
 378
 379         /**
 380          * Override the title of the page when viewed, provided we've been given a
 381          * title which will normalise to the canonical title
 382          *
 383          * @param Parser $parser Parent parser
 384          * @param string $text Desired title text
 385          * @param string $uarg
 386          * @return string
 387          */
 388         public static function displaytitle( $parser, $text = '', $uarg = '' ) {
 389                 global $wgRestrictDisplayTitle;
 390
 391                 static $magicWords = null;
 392                 if ( is_null( $magicWords ) ) {
 393                         $magicWords = new MagicWordArray( array( 'displaytitle_noerror', 'displaytitle_noreplace' ) );
 394                 }
 395                 $arg = $magicWords->matchStartToEnd( $uarg );
 396
 397                 // parse a limited subset of wiki markup (just the single quote items)
 398                 $text = $parser->doQuotes( $text );
 399
 400                 // remove stripped text (e.g. the UNIQ-QINU stuff) that was generated by tag extensions/whatever
 401                 $text = $parser->killMarkers( $text );
 402
 403                 // list of disallowed tags for DISPLAYTITLE
 404                 // these will be escaped even though they are allowed in normal wiki text
 405                 $bad = array( 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'div', 'blockquote', 'ol', 'ul', 'li', 'hr',
 406                         'table', 'tr', 'th', 'td', 'dl', 'dd', 'caption', 'p', 'ruby', 'rb', 'rt', 'rtc', 'rp', 'br' );
 407
 408                 // disallow some styles that could be used to bypass $wgRestrictDisplayTitle
 409                 if ( $wgRestrictDisplayTitle ) {
 410                         $htmlTagsCallback = function ( &$params ) {
 411                                 $decoded = Sanitizer::decodeTagAttributes( $params );
 412
 413                                 if ( isset( $decoded['style'] ) ) {
 414                                         // this is called later anyway, but we need it right now for the regexes below to be safe
 415                                         // calling it twice doesn't hurt
 416                                         $decoded['style'] = Sanitizer::checkCss( $decoded['style'] );
 417
 418                                         if ( preg_match( '/(display|user-select|visibility)\s*:/i', $decoded['style'] ) ) {
 419                                                 $decoded['style'] = '/* attempt to bypass $wgRestrictDisplayTitle */';
 420                                         }
 421                                 }
 422
 423                                 $params = Sanitizer::safeEncodeTagAttributes( $decoded );
 424                         };
 425                 } else {
 426                         $htmlTagsCallback = null;
 427                 }
 428
 429                 // only requested titles that normalize to the actual title are allowed through
 430                 // if $wgRestrictDisplayTitle is true (it is by default)
 431                 // mimic the escaping process that occurs in OutputPage::setPageTitle
 432                 $text = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags(
 433                         $text,
 434                         $htmlTagsCallback,
 435                         array(),
 436                         array(),
 437                         $bad
 438                 ) );
 439                 $title = Title::newFromText( Sanitizer::stripAllTags( $text ) );
 440
 441                 if ( !$wgRestrictDisplayTitle ||
 442                         ( $title instanceof Title
 443                         && !$title->hasFragment()
 444                         && $title->equals( $parser->mTitle ) )
 445                 ) {
 446                         $old = $parser->mOutput->getProperty( 'displaytitle' );
 447                         if ( $old === false || $arg !== 'displaytitle_noreplace' ) {
 448                                 $parser->mOutput->setDisplayTitle( $text );
 449                         }
 450                         if ( $old !== false && $old !== $text && !$arg ) {
 451                                 $converter = $parser->getConverterLanguage()->getConverter();
 452                                 return '<span class="error">' .
 453                                         wfMessage( 'duplicate-displaytitle',
 454                                                 // Message should be parsed, but these params should only be escaped.
 455                                                 $converter->markNoConversion( wfEscapeWikiText( $old ) ),
 456                                                 $converter->markNoConversion( wfEscapeWikiText( $text ) )
 457                                         )->inContentLanguage()->text() .
 458                                         '</span>';
 459                         }
 460                 }
 461
 462                 return '';
 463         }
 464
 465         /**
 466          * Matches the given value against the value of given magic word
 467          *
 468          * @param string $magicword Magic word key
 469          * @param string $value Value to match
 470          * @return bool True on successful match
 471          */
 472         private static function matchAgainstMagicword( $magicword, $value ) {
 473                 $value = trim( strval( $value ) );
 474                 if ( $value === '' ) {
 475                         return false;
 476                 }
 477                 $mwObject = MagicWord::get( $magicword );
 478                 return $mwObject->matchStartToEnd( $value );
 479         }
 480
 481         public static function formatRaw( $num, $raw ) {
 482                 if ( self::matchAgainstMagicword( 'rawsuffix', $raw ) ) {
 483                         return $num;
 484                 } else {
 485                         global $wgContLang;
 486                         return $wgContLang->formatNum( $num );
 487                 }
 488         }
 489         public static function numberofpages( $parser, $raw = null ) {
 490                 return self::formatRaw( SiteStats::pages(), $raw );
 491         }
 492         public static function numberofusers( $parser, $raw = null ) {
 493                 return self::formatRaw( SiteStats::users(), $raw );
 494         }
 495         public static function numberofactiveusers( $parser, $raw = null ) {
 496                 return self::formatRaw( SiteStats::activeUsers(), $raw );
 497         }
 498         public static function numberofarticles( $parser, $raw = null ) {
 499                 return self::formatRaw( SiteStats::articles(), $raw );
 500         }
 501         public static function numberoffiles( $parser, $raw = null ) {
 502                 return self::formatRaw( SiteStats::images(), $raw );
 503         }
 504         public static function numberofadmins( $parser, $raw = null ) {
 505                 return self::formatRaw( SiteStats::numberingroup( 'sysop' ), $raw );
 506         }
 507         public static function numberofedits( $parser, $raw = null ) {
 508                 return self::formatRaw( SiteStats::edits(), $raw );
 509         }
 510         public static function pagesinnamespace( $parser, $namespace = 0, $raw = null ) {
 511                 return self::formatRaw( SiteStats::pagesInNs( intval( $namespace ) ), $raw );
 512         }
 513         public static function numberingroup( $parser, $name = '', $raw = null ) {
 514                 return self::formatRaw( SiteStats::numberingroup( strtolower( $name ) ), $raw );
 515         }
 516
 517         /**
 518          * Given a title, return the namespace name that would be given by the
 519          * corresponding magic word
 520          * Note: function name changed to "mwnamespace" rather than "namespace"
 521          * to not break PHP 5.3
 522          * @param Parser $parser
 523          * @param string $title
 524          * @return mixed|string
 525          */
 526         public static function mwnamespace( $parser, $title = null ) {
 527                 $t = Title::newFromText( $title );
 528                 if ( is_null( $t ) ) {
 529                         return '';
 530                 }
 531                 return str_replace( '_', ' ', $t->getNsText() );
 532         }
 533         public static function namespacee( $parser, $title = null ) {
 534                 $t = Title::newFromText( $title );
 535                 if ( is_null( $t ) ) {
 536                         return '';
 537                 }
 538                 return wfUrlencode( $t->getNsText() );
 539         }
 540         public static function namespacenumber( $parser, $title = null ) {
 541                 $t = Title::newFromText( $title );
 542                 if ( is_null( $t ) ) {
 543                         return '';
 544                 }
 545                 return $t->getNamespace();
 546         }
 547         public static function talkspace( $parser, $title = null ) {
 548                 $t = Title::newFromText( $title );
 549                 if ( is_null( $t ) || !$t->canTalk() ) {
 550                         return '';
 551                 }
 552                 return str_replace( '_', ' ', $t->getTalkNsText() );
 553         }
 554         public static function talkspacee( $parser, $title = null ) {
 555                 $t = Title::newFromText( $title );
 556                 if ( is_null( $t ) || !$t->canTalk() ) {
 557                         return '';
 558                 }
 559                 return wfUrlencode( $t->getTalkNsText() );
 560         }
 561         public static function subjectspace( $parser, $title = null ) {
 562                 $t = Title::newFromText( $title );
 563                 if ( is_null( $t ) ) {
 564                         return '';
 565                 }
 566                 return str_replace( '_', ' ', $t->getSubjectNsText() );
 567         }
 568         public static function subjectspacee( $parser, $title = null ) {
 569                 $t = Title::newFromText( $title );
 570                 if ( is_null( $t ) ) {
 571                         return '';
 572                 }
 573                 return wfUrlencode( $t->getSubjectNsText() );
 574         }
 575
 576         /**
 577          * Functions to get and normalize pagenames, corresponding to the magic words
 578          * of the same names
 579          * @param Parser $parser
 580          * @param string $title
 581          * @return string
 582          */
 583         public static function pagename( $parser, $title = null ) {
 584                 $t = Title::newFromText( $title );
 585                 if ( is_null( $t ) ) {
 586                         return '';
 587                 }
 588                 return wfEscapeWikiText( $t->getText() );
 589         }
 590         public static function pagenamee( $parser, $title = null ) {
 591                 $t = Title::newFromText( $title );
 592                 if ( is_null( $t ) ) {
 593                         return '';
 594                 }
 595                 return wfEscapeWikiText( $t->getPartialURL() );
 596         }
 597         public static function fullpagename( $parser, $title = null ) {
 598                 $t = Title::newFromText( $title );
 599                 if ( is_null( $t ) || !$t->canTalk() ) {
 600                         return '';
 601                 }
 602                 return wfEscapeWikiText( $t->getPrefixedText() );
 603         }
 604         public static function fullpagenamee( $parser, $title = null ) {
 605                 $t = Title::newFromText( $title );
 606                 if ( is_null( $t ) || !$t->canTalk() ) {
 607                         return '';
 608                 }
 609                 return wfEscapeWikiText( $t->getPrefixedURL() );
 610         }
 611         public static function subpagename( $parser, $title = null ) {
 612                 $t = Title::newFromText( $title );
 613                 if ( is_null( $t ) ) {
 614                         return '';
 615                 }
 616                 return wfEscapeWikiText( $t->getSubpageText() );
 617         }
 618         public static function subpagenamee( $parser, $title = null ) {
 619                 $t = Title::newFromText( $title );
 620                 if ( is_null( $t ) ) {
 621                         return '';
 622                 }
 623                 return wfEscapeWikiText( $t->getSubpageUrlForm() );
 624         }
 625         public static function rootpagename( $parser, $title = null ) {
 626                 $t = Title::newFromText( $title );
 627                 if ( is_null( $t ) ) {
 628                         return '';
 629                 }
 630                 return wfEscapeWikiText( $t->getRootText() );
 631         }
 632         public static function rootpagenamee( $parser, $title = null ) {
 633                 $t = Title::newFromText( $title );
 634                 if ( is_null( $t ) ) {
 635                         return '';
 636                 }
 637                 return wfEscapeWikiText( wfUrlEncode( str_replace( ' ', '_', $t->getRootText() ) ) );
 638         }
 639         public static function basepagename( $parser, $title = null ) {
 640                 $t = Title::newFromText( $title );
 641                 if ( is_null( $t ) ) {
 642                         return '';
 643                 }
 644                 return wfEscapeWikiText( $t->getBaseText() );
 645         }
 646         public static function basepagenamee( $parser, $title = null ) {
 647                 $t = Title::newFromText( $title );
 648                 if ( is_null( $t ) ) {
 649                         return '';
 650                 }
 651                 return wfEscapeWikiText( wfUrlEncode( str_replace( ' ', '_', $t->getBaseText() ) ) );
 652         }
 653         public static function talkpagename( $parser, $title = null ) {
 654                 $t = Title::newFromText( $title );
 655                 if ( is_null( $t ) || !$t->canTalk() ) {
 656                         return '';
 657                 }
 658                 return wfEscapeWikiText( $t->getTalkPage()->getPrefixedText() );
 659         }
 660         public static function talkpagenamee( $parser, $title = null ) {
 661                 $t = Title::newFromText( $title );
 662                 if ( is_null( $t ) || !$t->canTalk() ) {
 663                         return '';
 664                 }
 665                 return wfEscapeWikiText( $t->getTalkPage()->getPrefixedURL() );
 666         }
 667         public static function subjectpagename( $parser, $title = null ) {
 668                 $t = Title::newFromText( $title );
 669                 if ( is_null( $t ) ) {
 670                         return '';
 671                 }
 672                 return wfEscapeWikiText( $t->getSubjectPage()->getPrefixedText() );
 673         }
 674         public static function subjectpagenamee( $parser, $title = null ) {
 675                 $t = Title::newFromText( $title );
 676                 if ( is_null( $t ) ) {
 677                         return '';
 678                 }
 679                 return wfEscapeWikiText( $t->getSubjectPage()->getPrefixedURL() );
 680         }
 681
 682         /**
 683          * Return the number of pages, files or subcats in the given category,
 684          * or 0 if it's nonexistent. This is an expensive parser function and
 685          * can't be called too many times per page.
 686          * @param Parser $parser
 687          * @param string $name
 688          * @param string $arg1
 689          * @param string $arg2
 690          * @return string
 691          */
 692         public static function pagesincategory( $parser, $name = '', $arg1 = null, $arg2 = null ) {
 693                 global $wgContLang;
 694                 static $magicWords = null;
 695                 if ( is_null( $magicWords ) ) {
 696                         $magicWords = new MagicWordArray( array(
 697                                 'pagesincategory_all',
 698                                 'pagesincategory_pages',
 699                                 'pagesincategory_subcats',
 700                                 'pagesincategory_files'
 701                         ) );
 702                 }
 703                 static $cache = array();
 704
 705                 // split the given option to its variable
 706                 if ( self::matchAgainstMagicword( 'rawsuffix', $arg1 ) ) {
 707                         //{{pagesincategory:|raw[|type]}}
 708                         $raw = $arg1;
 709                         $type = $magicWords->matchStartToEnd( $arg2 );
 710                 } else {
 711                         //{{pagesincategory:[|type[|raw]]}}
 712                         $type = $magicWords->matchStartToEnd( $arg1 );
 713                         $raw = $arg2;
 714                 }
 715                 if ( !$type ) { //backward compatibility
 716                         $type = 'pagesincategory_all';
 717                 }
 718
 719                 $title = Title::makeTitleSafe( NS_CATEGORY, $name );
 720                 if ( !$title ) { # invalid title
 721                         return self::formatRaw( 0, $raw );
 722                 }
 723                 $wgContLang->findVariantLink( $name, $title, true );
 724
 725                 // Normalize name for cache
 726                 $name = $title->getDBkey();
 727
 728                 if ( !isset( $cache[$name] ) ) {
 729                         $category = Category::newFromTitle( $title );
 730
 731                         $allCount = $subcatCount = $fileCount = $pagesCount = 0;
 732                         if ( $parser->incrementExpensiveFunctionCount() ) {
 733                                 // $allCount is the total number of cat members,
 734                                 // not the count of how many members are normal pages.
 735                                 $allCount = (int)$category->getPageCount();
 736                                 $subcatCount = (int)$category->getSubcatCount();
 737                                 $fileCount = (int)$category->getFileCount();
 738                                 $pagesCount = $allCount - $subcatCount - $fileCount;
 739                         }
 740                         $cache[$name]['pagesincategory_all'] = $allCount;
 741                         $cache[$name]['pagesincategory_pages'] = $pagesCount;
 742                         $cache[$name]['pagesincategory_subcats'] = $subcatCount;
 743                         $cache[$name]['pagesincategory_files'] = $fileCount;
 744                 }
 745
 746                 $count = $cache[$name][$type];
 747                 return self::formatRaw( $count, $raw );
 748         }
 749
 750         /**
 751          * Return the size of the given page, or 0 if it's nonexistent.  This is an
 752          * expensive parser function and can't be called too many times per page.
 753          *
 754          * @param Parser $parser
 755          * @param string $page Name of page to check (Default: empty string)
 756          * @param string $raw Should number be human readable with commas or just number
 757          * @return string
 758          */
 759         public static function pagesize( $parser, $page = '', $raw = null ) {
 760                 $title = Title::newFromText( $page );
 761
 762                 if ( !is_object( $title ) ) {
 763                         return self::formatRaw( 0, $raw );
 764                 }
 765
 766                 // fetch revision from cache/database and return the value
 767                 $rev = self::getCachedRevisionObject( $parser, $title );
 768                 $length = $rev ? $rev->getSize() : 0;
 769                 return self::formatRaw( $length, $raw );
 770         }
 771
 772         /**
 773          * Returns the requested protection level for the current page. This
 774          * is an expensive parser function and can't be called too many times
 775          * per page, unless the protection levels for the given title have
 776          * already been retrieved
 777          *
 778          * @param Parser $parser
 779          * @param string $type
 780          * @param string $title
 781          *
 782          * @return string
 783          */
 784         public static function protectionlevel( $parser, $type = '', $title = '' ) {
 785                 $titleObject = Title::newFromText( $title );
 786                 if ( !( $titleObject instanceof Title ) ) {
 787                         $titleObject = $parser->mTitle;
 788                 }
 789                 if ( $titleObject->areRestrictionsLoaded() || $parser->incrementExpensiveFunctionCount() ) {
 790                         $restrictions = $titleObject->getRestrictions( strtolower( $type ) );
 791                         # Title::getRestrictions returns an array, its possible it may have
 792                         # multiple values in the future
 793                         return implode( $restrictions, ',' );
 794                 }
 795                 return '';
 796         }
 797
 798         /**
 799          * Gives language names.
 800          * @param Parser $parser
 801          * @param string $code Language code (of which to get name)
 802          * @param string $inLanguage Language code (in which to get name)
 803          * @return string
 804          */
 805         public static function language( $parser, $code = '', $inLanguage = '' ) {
 806                 $code = strtolower( $code );
 807                 $inLanguage = strtolower( $inLanguage );
 808                 $lang = Language::fetchLanguageName( $code, $inLanguage );
 809                 return $lang !== '' ? $lang : wfBCP47( $code );
 810         }
 811
 812         /**
 813          * Unicode-safe str_pad with the restriction that $length is forced to be <= 500
 814          * @param Parser $parser
 815          * @param string $string
 816          * @param int $length
 817          * @param string $padding
 818          * @param int $direction
 819          * @return string
 820          */
 821         public static function pad(
 822                 $parser, $string, $length, $padding = '0', $direction = STR_PAD_RIGHT
 823         ) {
 824                 $padding = $parser->killMarkers( $padding );
 825                 $lengthOfPadding = mb_strlen( $padding );
 826                 if ( $lengthOfPadding == 0 ) {
 827                         return $string;
 828                 }
 829
 830                 # The remaining length to add counts down to 0 as padding is added
 831                 $length = min( $length, 500 ) - mb_strlen( $string );
 832                 # $finalPadding is just $padding repeated enough times so that
 833                 # mb_strlen( $string ) + mb_strlen( $finalPadding ) == $length
 834                 $finalPadding = '';
 835                 while ( $length > 0 ) {
 836                         # If $length < $lengthofPadding, truncate $padding so we get the
 837                         # exact length desired.
 838                         $finalPadding .= mb_substr( $padding, 0, $length );
 839                         $length -= $lengthOfPadding;
 840                 }
 841
 842                 if ( $direction == STR_PAD_LEFT ) {
 843                         return $finalPadding . $string;
 844                 } else {
 845                         return $string . $finalPadding;
 846                 }
 847         }
 848
 849         public static function padleft( $parser, $string = '', $length = 0, $padding = '0' ) {
 850                 return self::pad( $parser, $string, $length, $padding, STR_PAD_LEFT );
 851         }
 852
 853         public static function padright( $parser, $string = '', $length = 0, $padding = '0' ) {
 854                 return self::pad( $parser, $string, $length, $padding );
 855         }
 856
 857         /**
 858          * @param Parser $parser
 859          * @param string $text
 860          * @return string
 861          */
 862         public static function anchorencode( $parser, $text ) {
 863                 $text = $parser->killMarkers( $text );
 864                 return (string)substr( $parser->guessSectionNameFromWikiText( $text ), 1 );
 865         }
 866
 867         public static function special( $parser, $text ) {
 868                 list( $page, $subpage ) = SpecialPageFactory::resolveAlias( $text );
 869                 if ( $page ) {
 870                         $title = SpecialPage::getTitleFor( $page, $subpage );
 871                         return $title->getPrefixedText();
 872                 } else {
 873                         // unknown special page, just use the given text as its title, if at all possible
 874                         $title = Title::makeTitleSafe( NS_SPECIAL, $text );
 875                         return $title ? $title->getPrefixedText() : self::special( $parser, 'Badtitle' );
 876                 }
 877         }
 878
 879         public static function speciale( $parser, $text ) {
 880                 return wfUrlencode( str_replace( ' ', '_', self::special( $parser, $text ) ) );
 881         }
 882
 883         /**
 884          * @param Parser $parser
 885          * @param string $text The sortkey to use
 886          * @param string $uarg Either "noreplace" or "noerror" (in en)
 887          *   both suppress errors, and noreplace does nothing if
 888          *   a default sortkey already exists.
 889          * @return string
 890          */
 891         public static function defaultsort( $parser, $text, $uarg = '' ) {
 892                 static $magicWords = null;
 893                 if ( is_null( $magicWords ) ) {
 894                         $magicWords = new MagicWordArray( array( 'defaultsort_noerror', 'defaultsort_noreplace' ) );
 895                 }
 896                 $arg = $magicWords->matchStartToEnd( $uarg );
 897
 898                 $text = trim( $text );
 899                 if ( strlen( $text ) == 0 ) {
 900                         return '';
 901                 }
 902                 $old = $parser->getCustomDefaultSort();
 903                 if ( $old === false || $arg !== 'defaultsort_noreplace' ) {
 904                         $parser->setDefaultSort( $text );
 905                 }
 906
 907                 if ( $old === false || $old == $text || $arg ) {
 908                         return '';
 909                 } else {
 910                         $converter = $parser->getConverterLanguage()->getConverter();
 911                         return '<span class="error">' .
 912                                 wfMessage( 'duplicate-defaultsort',
 913                                         // Message should be parsed, but these params should only be escaped.
 914                                         $converter->markNoConversion( wfEscapeWikiText( $old ) ),
 915                                         $converter->markNoConversion( wfEscapeWikiText( $text ) )
 916                                 )->inContentLanguage()->text() .
 917                                 '</span>';
 918                 }
 919         }
 920
 921         /**
 922          * Usage {{filepath|300}}, {{filepath|nowiki}}, {{filepath|nowiki|300}}
 923          * or {{filepath|300|nowiki}} or {{filepath|300px}}, {{filepath|200x300px}},
 924          * {{filepath|nowiki|200x300px}}, {{filepath|200x300px|nowiki}}.
 925          *
 926          * @param Parser $parser
 927          * @param string $name
 928          * @param string $argA
 929          * @param string $argB
 930          * @return array|string
 931          */
 932         public static function filepath( $parser, $name = '', $argA = '', $argB = '' ) {
 933                 $file = wfFindFile( $name );
 934
 935                 if ( $argA == 'nowiki' ) {
 936                         // {{filepath: | option [| size] }}
 937                         $isNowiki = true;
 938                         $parsedWidthParam = $parser->parseWidthParam( $argB );
 939                 } else {
 940                         // {{filepath: [| size [|option]] }}
 941                         $parsedWidthParam = $parser->parseWidthParam( $argA );
 942                         $isNowiki = ( $argB == 'nowiki' );
 943                 }
 944
 945                 if ( $file ) {
 946                         $url = $file->getFullUrl();
 947
 948                         // If a size is requested...
 949                         if ( count( $parsedWidthParam ) ) {
 950                                 $mto = $file->transform( $parsedWidthParam );
 951                                 // ... and we can
 952                                 if ( $mto && !$mto->isError() ) {
 953                                         // ... change the URL to point to a thumbnail.
 954                                         $url = wfExpandUrl( $mto->getUrl(), PROTO_RELATIVE );
 955                                 }
 956                         }
 957                         if ( $isNowiki ) {
 958                                 return array( $url, 'nowiki' => true );
 959                         }
 960                         return $url;
 961                 } else {
 962                         return '';
 963                 }
 964         }
 965
 966         /**
 967          * Parser function to extension tag adaptor
 968          * @param Parser $parser
 969          * @param PPFrame $frame
 970          * @param PPNode[] $args
 971          * @return string
 972          */
 973         public static function tagObj( $parser, $frame, $args ) {
 974                 if ( !count( $args ) ) {
 975                         return '';
 976                 }
 977                 $tagName = strtolower( trim( $frame->expand( array_shift( $args ) ) ) );
 978
 979                 if ( count( $args ) ) {
 980                         $inner = $frame->expand( array_shift( $args ) );
 981                 } else {
 982                         $inner = null;
 983                 }
 984
 985                 $attributes = array();
 986                 foreach ( $args as $arg ) {
 987                         $bits = $arg->splitArg();
 988                         if ( strval( $bits['index'] ) === '' ) {
 989                                 $name = trim( $frame->expand( $bits['name'], PPFrame::STRIP_COMMENTS ) );
 990                                 $value = trim( $frame->expand( $bits['value'] ) );
 991                                 if ( preg_match( '/^(?:["\'](.+)["\']|""|\'\')$/s', $value, $m ) ) {
 992                                         $value = isset( $m[1] ) ? $m[1] : '';
 993                                 }
 994                                 $attributes[$name] = $value;
 995                         }
 996                 }
 997
 998                 $stripList = $parser->getStripList();
 999                 if ( !in_array( $tagName, $stripList ) ) {
1000                         // we can't handle this tag (at least not now), so just re-emit it as an ordinary tag
1001                         $attrText = '';
1002                         foreach ( $attributes as $name => $value ) {
1003                                 $attrText .= ' ' . htmlspecialchars( $name ) . '="' . htmlspecialchars( $value ) . '"';
1004                         }
1005                         if ( $inner === null ) {
1006                                 return "<$tagName$attrText/>";
1007                         }
1008                         return "<$tagName$attrText>$inner</$tagName>";
1009                 }
1010
1011                 $params = array(
1012                         'name' => $tagName,
1013                         'inner' => $inner,
1014                         'attributes' => $attributes,
1015                         'close' => "</$tagName>",
1016                 );
1017                 return $parser->extensionSubstitution( $params, $frame );
1018         }
1019
1020         /**
1021          * Fetched the current revision of the given title and return this.
1022          * Will increment the expensive function count and
1023          * add a template link to get the value refreshed on changes.
1024          * For a given title, which is equal to the current parser title,
1025          * the revision object from the parser is used, when that is the current one
1026          *
1027          * @param Parser $parser
1028          * @param Title $title
1029          * @return Revision
1030          * @since 1.23
1031          */
1032         private static function getCachedRevisionObject( $parser, $title = null ) {
1033                 if ( is_null( $title ) ) {
1034                         return null;
1035                 }
1036
1037                 // Use the revision from the parser itself, when param is the current page
1038                 // and the revision is the current one
1039                 if ( $title->equals( $parser->getTitle() ) ) {
1040                         $parserRev = $parser->getRevisionObject();
1041                         if ( $parserRev && $parserRev->isCurrent() ) {
1042                                 // force reparse after edit with vary-revision flag
1043                                 $parser->getOutput()->setFlag( 'vary-revision' );
1044                                 wfDebug( __METHOD__ . ": use current revision from parser, setting vary-revision...\n" );
1045                                 return $parserRev;
1046                         }
1047                 }
1048
1049                 // Normalize name for cache
1050                 $page = $title->getPrefixedDBkey();
1051
1052                 if ( !( $parser->currentRevisionCache && $parser->currentRevisionCache->has( $page ) )
1053                         && !$parser->incrementExpensiveFunctionCount() ) {
1054                         return null;
1055                 }
1056                 $rev = $parser->fetchCurrentRevisionOfTitle( $title );
1057                 $pageID = $rev ? $rev->getPage() : 0;
1058                 $revID = $rev ? $rev->getId() : 0;
1059
1060                 // Register dependency in templatelinks
1061                 $parser->getOutput()->addTemplate( $title, $pageID, $revID );
1062
1063                 return $rev;
1064         }
1065
1066         /**
1067          * Get the pageid of a specified page
1068          * @param Parser $parser
1069          * @param string $title Title to get the pageid from
1070          * @return int|null|string
1071          * @since 1.23
1072          */
1073         public static function pageid( $parser, $title = null ) {
1074                 $t = Title::newFromText( $title );
1075                 if ( is_null( $t ) ) {
1076                         return '';
1077                 }
1078                 // Use title from parser to have correct pageid after edit
1079                 if ( $t->equals( $parser->getTitle() ) ) {
1080                         $t = $parser->getTitle();
1081                         return $t->getArticleID();
1082                 }
1083
1084                 // These can't have ids
1085                 if ( !$t->canExist() || $t->isExternal() ) {
1086                         return 0;
1087                 }
1088
1089                 // Check the link cache, maybe something already looked it up.
1090                 $linkCache = LinkCache::singleton();
1091                 $pdbk = $t->getPrefixedDBkey();
1092                 $id = $linkCache->getGoodLinkID( $pdbk );
1093                 if ( $id != 0 ) {
1094                         $parser->mOutput->addLink( $t, $id );
1095                         return $id;
1096                 }
1097                 if ( $linkCache->isBadLink( $pdbk ) ) {
1098                         $parser->mOutput->addLink( $t, 0 );
1099                         return $id;
1100                 }
1101
1102                 // We need to load it from the DB, so mark expensive
1103                 if ( $parser->incrementExpensiveFunctionCount() ) {
1104                         $id = $t->getArticleID();
1105                         $parser->mOutput->addLink( $t, $id );
1106                         return $id;
1107                 }
1108                 return null;
1109         }
1110
1111         /**
1112          * Get the id from the last revision of a specified page.
1113          * @param Parser $parser
1114          * @param string $title Title to get the id from
1115          * @return int|null|string
1116          * @since 1.23
1117          */
1118         public static function revisionid( $parser, $title = null ) {
1119                 $t = Title::newFromText( $title );
1120                 if ( is_null( $t ) ) {
1121                         return '';
1122                 }
1123                 // fetch revision from cache/database and return the value
1124                 $rev = self::getCachedRevisionObject( $parser, $t );
1125                 return $rev ? $rev->getId() : '';
1126         }
1127
1128         /**
1129          * Get the day from the last revision of a specified page.
1130          * @param Parser $parser
1131          * @param string $title Title to get the day from
1132          * @return string
1133          * @since 1.23
1134          */
1135         public static function revisionday( $parser, $title = null ) {
1136                 $t = Title::newFromText( $title );
1137                 if ( is_null( $t ) ) {
1138                         return '';
1139                 }
1140                 // fetch revision from cache/database and return the value
1141                 $rev = self::getCachedRevisionObject( $parser, $t );
1142                 return $rev ? MWTimestamp::getLocalInstance( $rev->getTimestamp() )->format( 'j' ) : '';
1143         }
1144
1145         /**
1146          * Get the day with leading zeros from the last revision of a specified page.
1147          * @param Parser $parser
1148          * @param string $title Title to get the day from
1149          * @return string
1150          * @since 1.23
1151          */
1152         public static function revisionday2( $parser, $title = null ) {
1153                 $t = Title::newFromText( $title );
1154                 if ( is_null( $t ) ) {
1155                         return '';
1156                 }
1157                 // fetch revision from cache/database and return the value
1158                 $rev = self::getCachedRevisionObject( $parser, $t );
1159                 return $rev ? MWTimestamp::getLocalInstance( $rev->getTimestamp() )->format( 'd' ) : '';
1160         }
1161
1162         /**
1163          * Get the month with leading zeros from the last revision of a specified page.
1164          * @param Parser $parser
1165          * @param string $title Title to get the month from
1166          * @return string
1167          * @since 1.23
1168          */
1169         public static function revisionmonth( $parser, $title = null ) {
1170                 $t = Title::newFromText( $title );
1171                 if ( is_null( $t ) ) {
1172                         return '';
1173                 }
1174                 // fetch revision from cache/database and return the value
1175                 $rev = self::getCachedRevisionObject( $parser, $t );
1176                 return $rev ? MWTimestamp::getLocalInstance( $rev->getTimestamp() )->format( 'm' ) : '';
1177         }
1178
1179         /**
1180          * Get the month from the last revision of a specified page.
1181          * @param Parser $parser
1182          * @param string $title Title to get the month from
1183          * @return string
1184          * @since 1.23
1185          */
1186         public static function revisionmonth1( $parser, $title = null ) {
1187                 $t = Title::newFromText( $title );
1188                 if ( is_null( $t ) ) {
1189                         return '';
1190                 }
1191                 // fetch revision from cache/database and return the value
1192                 $rev = self::getCachedRevisionObject( $parser, $t );
1193                 return $rev ? MWTimestamp::getLocalInstance( $rev->getTimestamp() )->format( 'n' ) : '';
1194         }
1195
1196         /**
1197          * Get the year from the last revision of a specified page.
1198          * @param Parser $parser
1199          * @param string $title Title to get the year from
1200          * @return string
1201          * @since 1.23
1202          */
1203         public static function revisionyear( $parser, $title = null ) {
1204                 $t = Title::newFromText( $title );
1205                 if ( is_null( $t ) ) {
1206                         return '';
1207                 }
1208                 // fetch revision from cache/database and return the value
1209                 $rev = self::getCachedRevisionObject( $parser, $t );
1210                 return $rev ? MWTimestamp::getLocalInstance( $rev->getTimestamp() )->format( 'Y' ) : '';
1211         }
1212
1213         /**
1214          * Get the timestamp from the last revision of a specified page.
1215          * @param Parser $parser
1216          * @param string $title Title to get the timestamp from
1217          * @return string
1218          * @since 1.23
1219          */
1220         public static function revisiontimestamp( $parser, $title = null ) {
1221                 $t = Title::newFromText( $title );
1222                 if ( is_null( $t ) ) {
1223                         return '';
1224                 }
1225                 // fetch revision from cache/database and return the value
1226                 $rev = self::getCachedRevisionObject( $parser, $t );
1227                 return $rev ? MWTimestamp::getLocalInstance( $rev->getTimestamp() )->format( 'YmdHis' ) : '';
1228         }
1229
1230         /**
1231          * Get the user from the last revision of a specified page.
1232          * @param Parser $parser
1233          * @param string $title Title to get the user from
1234          * @return string
1235          * @since 1.23
1236          */
1237         public static function revisionuser( $parser, $title = null ) {
1238                 $t = Title::newFromText( $title );
1239                 if ( is_null( $t ) ) {
1240                         return '';
1241                 }
1242                 // fetch revision from cache/database and return the value
1243                 $rev = self::getCachedRevisionObject( $parser, $t );
1244                 return $rev ? $rev->getUserText() : '';
1245         }
1246
1247         /**
1248          * Returns the sources of any cascading protection acting on a specified page.
1249          * Pages will not return their own title unless they transclude themselves.
1250          * This is an expensive parser function and can't be called too many times per page,
1251          * unless cascading protection sources for the page have already been loaded.
1252          *
1253          * @param Parser $parser
1254          * @param string $title
1255          *
1256          * @return string
1257          * @since 1.23
1258          */
1259         public static function cascadingsources( $parser, $title = '' ) {
1260                 $titleObject = Title::newFromText( $title );
1261                 if ( !( $titleObject instanceof Title ) ) {
1262                         $titleObject = $parser->mTitle;
1263                 }
1264                 if ( $titleObject->areCascadeProtectionSourcesLoaded()
1265                         || $parser->incrementExpensiveFunctionCount()
1266                 ) {
1267                         $names = array();
1268                         $sources = $titleObject->getCascadeProtectionSources();
1269                         foreach ( $sources[0] as $sourceTitle ) {
1270                                 $names[] = $sourceTitle->getPrefixedText();
1271                         }
1272                         return implode( $names, '|' );
1273                 }
1274                 return '';
1275         }
1276
1277 }