includes/parser/ParserOutput.php

   1 <?php
   2
   3 /**
   4  * Output of the PHP parser.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  * http://www.gnu.org/copyleft/gpl.html
  20  *
  21  * @file
  22  * @ingroup Parser
  23  */
  24
  25 class ParserOutput extends CacheTime {
  26         /**
  27          * Feature flags to indicate to extensions that MediaWiki core supports and
  28          * uses getText() stateless transforms.
  29          *
  30          * @since 1.31
  31          */
  32         const SUPPORTS_STATELESS_TRANSFORMS = 1;
  33
  34         /**
  35          * @since 1.31
  36          */
  37         const SUPPORTS_UNWRAP_TRANSFORM = 1;
  38
  39         /**
  40          * @var string|null $mText The output text
  41          */
  42         public $mText = null;
  43
  44         /**
  45          * @var array $mLanguageLinks List of the full text of language links,
  46          *  in the order they appear.
  47          */
  48         public $mLanguageLinks;
  49
  50         /**
  51          * @var array $mCategories Map of category names to sort keys
  52          */
  53         public $mCategories;
  54
  55         /**
  56          * @var array $mIndicators Page status indicators, usually displayed in top-right corner.
  57          */
  58         public $mIndicators = [];
  59
  60         /**
  61          * @var string $mTitleText Title text of the chosen language variant, as HTML.
  62          */
  63         public $mTitleText;
  64
  65         /**
  66          * @var array $mLinks 2-D map of NS/DBK to ID for the links in the document.
  67          *  ID=zero for broken.
  68          */
  69         public $mLinks = [];
  70
  71         /**
  72          * @var array $mTemplates 2-D map of NS/DBK to ID for the template references.
  73          *  ID=zero for broken.
  74          */
  75         public $mTemplates = [];
  76
  77         /**
  78          * @var array $mTemplateIds 2-D map of NS/DBK to rev ID for the template references.
  79          *  ID=zero for broken.
  80          */
  81         public $mTemplateIds = [];
  82
  83         /**
  84          * @var array $mImages DB keys of the images used, in the array key only
  85          */
  86         public $mImages = [];
  87
  88         /**
  89          * @var array $mFileSearchOptions DB keys of the images used mapped to sha1 and MW timestamp.
  90          */
  91         public $mFileSearchOptions = [];
  92
  93         /**
  94          * @var array $mExternalLinks External link URLs, in the key only.
  95          */
  96         public $mExternalLinks = [];
  97
  98         /**
  99          * @var array $mInterwikiLinks 2-D map of prefix/DBK (in keys only)
 100          *  for the inline interwiki links in the document.
 101          */
 102         public $mInterwikiLinks = [];
 103
 104         /**
 105          * @var bool $mNewSection Show a new section link?
 106          */
 107         public $mNewSection = false;
 108
 109         /**
 110          * @var bool $mHideNewSection Hide the new section link?
 111          */
 112         public $mHideNewSection = false;
 113
 114         /**
 115          * @var bool $mNoGallery No gallery on category page? (__NOGALLERY__).
 116          */
 117         public $mNoGallery = false;
 118
 119         /**
 120          * @var array $mHeadItems Items to put in the <head> section
 121          */
 122         public $mHeadItems = [];
 123
 124         /**
 125          * @var array $mModules Modules to be loaded by ResourceLoader
 126          */
 127         public $mModules = [];
 128
 129         /**
 130          * @var array $mModuleStyles Modules of which only the CSSS will be loaded by ResourceLoader.
 131          */
 132         public $mModuleStyles = [];
 133
 134         /**
 135          * @var array $mJsConfigVars JavaScript config variable for mw.config combined with this page.
 136          */
 137         public $mJsConfigVars = [];
 138
 139         /**
 140          * @var array $mOutputHooks Hook tags as per $wgParserOutputHooks.
 141          */
 142         public $mOutputHooks = [];
 143
 144         /**
 145          * @var array $mWarnings Warning text to be returned to the user.
 146          *  Wikitext formatted, in the key only.
 147          */
 148         public $mWarnings = [];
 149
 150         /**
 151          * @var array $mSections Table of contents
 152          */
 153         public $mSections = [];
 154
 155         /**
 156          * @var array $mProperties Name/value pairs to be cached in the DB.
 157          */
 158         public $mProperties = [];
 159
 160         /**
 161          * @var string $mTOCHTML HTML of the TOC.
 162          */
 163         public $mTOCHTML = '';
 164
 165         /**
 166          * @var string $mTimestamp Timestamp of the revision.
 167          */
 168         public $mTimestamp;
 169
 170         /**
 171          * @var bool $mEnableOOUI Whether OOUI should be enabled.
 172          */
 173         public $mEnableOOUI = false;
 174
 175         /**
 176          * @var string $mIndexPolicy 'index' or 'noindex'?  Any other value will result in no change.
 177          */
 178         private $mIndexPolicy = '';
 179
 180         /**
 181          * @var true[] $mAccessedOptions List of ParserOptions (stored in the keys).
 182          */
 183         private $mAccessedOptions = [];
 184
 185         /**
 186          * @var array $mExtensionData extra data used by extensions.
 187          */
 188         private $mExtensionData = [];
 189
 190         /**
 191          * @var array $mLimitReportData Parser limit report data.
 192          */
 193         private $mLimitReportData = [];
 194
 195         /** @var array Parser limit report data for JSON */
 196         private $mLimitReportJSData = [];
 197
 198         /**
 199          * @var array $mParseStartTime Timestamps for getTimeSinceStart().
 200          */
 201         private $mParseStartTime = [];
 202
 203         /**
 204          * @var bool $mPreventClickjacking Whether to emit X-Frame-Options: DENY.
 205          */
 206         private $mPreventClickjacking = false;
 207
 208         /**
 209          * @var array $mFlags Generic flags.
 210          */
 211         private $mFlags = [];
 212
 213         /** @var int|null Assumed rev ID for {{REVISIONID}} if no revision is set */
 214         private $mSpeculativeRevId;
 215
 216         /** string CSS classes to use for the wrapping div, stored in the array keys.
 217          * If no class is given, no wrapper is added.
 218          */
 219         private $mWrapperDivClasses = [];
 220
 221         /** @var int Upper bound of expiry based on parse duration */
 222         private $mMaxAdaptiveExpiry = INF;
 223
 224         const EDITSECTION_REGEX =
 225                 '#<(?:mw:)?editsection page="(.*?)" section="(.*?)"(?:/>|>(.*?)(</(?:mw:)?editsection>))#s';
 226
 227         // finalizeAdaptiveCacheExpiry() uses TTL = MAX( m * PARSE_TIME + b, MIN_AR_TTL)
 228         // Current values imply that m=3933.333333 and b=-333.333333
 229         // See https://www.nngroup.com/articles/website-response-times/
 230         const PARSE_FAST_SEC = 0.100; // perceived "fast" page parse
 231         const PARSE_SLOW_SEC = 1.0; // perceived "slow" page parse
 232         const FAST_AR_TTL = 60; // adaptive TTL for "fast" pages
 233         const SLOW_AR_TTL = 3600; // adaptive TTL for "slow" pages
 234         const MIN_AR_TTL = 15; // min adaptive TTL (for sanity, pool counter, and edit stashing)
 235
 236         /**
 237          * @param string|null $text HTML. Use null to indicate that this ParserOutput contains only
 238          *        meta-data, and the HTML output is undetermined, as opposed to empty. Passing null
 239          *        here causes hasText() to return false.
 240          * @param array $languageLinks
 241          * @param array $categoryLinks
 242          * @param bool $unused
 243          * @param string $titletext
 244          */
 245         public function __construct( $text = '', $languageLinks = [], $categoryLinks = [],
 246                 $unused = false, $titletext = ''
 247         ) {
 248                 $this->mText = $text;
 249                 $this->mLanguageLinks = $languageLinks;
 250                 $this->mCategories = $categoryLinks;
 251                 $this->mTitleText = $titletext;
 252         }
 253
 254         /**
 255          * Returns true if text was passed to the constructor, or set using setText(). Returns false
 256          * if null was passed to the $text parameter of the constructor to indicate that this
 257          * ParserOutput only contains meta-data, and the HTML output is undetermined.
 258          *
 259          * @since 1.32
 260          *
 261          * @return bool Whether this ParserOutput contains rendered text. If this returns false, the
 262          *         ParserOutput contains meta-data only.
 263          */
 264         public function hasText() {
 265                 return ( $this->mText !== null );
 266         }
 267
 268         /**
 269          * Get the cacheable text with <mw:editsection> markers still in it. The
 270          * return value is suitable for writing back via setText() but is not valid
 271          * for display to the user.
 272          *
 273          * @return string
 274          * @since 1.27
 275          */
 276         public function getRawText() {
 277                 if ( $this->mText === null ) {
 278                         throw new LogicException( 'This ParserOutput contains no text!' );
 279                 }
 280
 281                 return $this->mText;
 282         }
 283
 284         /**
 285          * Get the output HTML
 286          *
 287          * @param array $options (since 1.31) Transformations to apply to the HTML
 288          *  - allowTOC: (bool) Show the TOC, assuming there were enough headings
 289          *     to generate one and `__NOTOC__` wasn't used. Default is true,
 290          *     but might be statefully overridden.
 291          *  - enableSectionEditLinks: (bool) Include section edit links, assuming
 292          *     section edit link tokens are present in the HTML. Default is true,
 293          *     but might be statefully overridden.
 294          *  - unwrap: (bool) Return text without a wrapper div. Default is false,
 295          *    meaning a wrapper div will be added if getWrapperDivClass() returns
 296          *    a non-empty string.
 297          *  - wrapperDivClass: (string) Wrap the output in a div and apply the given
 298          *    CSS class to that div. This overrides the output of getWrapperDivClass().
 299          *    Setting this to an empty string has the same effect as 'unwrap' => true.
 300          *  - deduplicateStyles: (bool) When true, which is the default, `<style>`
 301          *    tags with the `data-mw-deduplicate` attribute set are deduplicated by
 302          *    value of the attribute: all but the first will be replaced by `<link
 303          *    rel="mw-deduplicated-inline-style" href="mw-data:..."/>` tags, where
 304          *    the scheme-specific-part of the href is the (percent-encoded) value
 305          *    of the `data-mw-deduplicate` attribute.
 306          * @return string HTML
 307          * @return-taint escaped
 308          */
 309         public function getText( $options = [] ) {
 310                 $options += [
 311                         'allowTOC' => true,
 312                         'enableSectionEditLinks' => true,
 313                         'unwrap' => false,
 314                         'deduplicateStyles' => true,
 315                         'wrapperDivClass' => $this->getWrapperDivClass(),
 316                 ];
 317                 $text = $this->getRawText();
 318
 319                 Hooks::runWithoutAbort( 'ParserOutputPostCacheTransform', [ $this, &$text, &$options ] );
 320
 321                 if ( $options['wrapperDivClass'] !== '' && !$options['unwrap'] ) {
 322                         $text = Html::rawElement( 'div', [ 'class' => $options['wrapperDivClass'] ], $text );
 323                 }
 324
 325                 if ( $options['enableSectionEditLinks'] ) {
 326                         $text = preg_replace_callback(
 327                                 self::EDITSECTION_REGEX,
 328                                 function ( $m ) {
 329                                         $editsectionPage = Title::newFromText( htmlspecialchars_decode( $m[1] ) );
 330                                         $editsectionSection = htmlspecialchars_decode( $m[2] );
 331                                         $editsectionContent = isset( $m[4] ) ? Sanitizer::decodeCharReferences( $m[3] ) : null;
 332
 333                                         if ( !is_object( $editsectionPage ) ) {
 334                                                 throw new MWException( "Bad parser output text." );
 335                                         }
 336
 337                                         $context = RequestContext::getMain();
 338                                         return $context->getSkin()->doEditSectionLink(
 339                                                 $editsectionPage,
 340                                                 $editsectionSection,
 341                                                 $editsectionContent,
 342                                                 $context->getLanguage()
 343                                         );
 344                                 },
 345                                 $text
 346                         );
 347                 } else {
 348                         $text = preg_replace( self::EDITSECTION_REGEX, '', $text );
 349                 }
 350
 351                 if ( $options['allowTOC'] ) {
 352                         $text = str_replace( [ Parser::TOC_START, Parser::TOC_END ], '', $text );
 353                 } else {
 354                         $text = preg_replace(
 355                                 '#' . preg_quote( Parser::TOC_START, '#' ) . '.*?' . preg_quote( Parser::TOC_END, '#' ) . '#s',
 356                                 '',
 357                                 $text
 358                         );
 359                 }
 360
 361                 if ( $options['deduplicateStyles'] ) {
 362                         $seen = [];
 363                         $text = preg_replace_callback(
 364                                 '#<style\s+([^>]*data-mw-deduplicate\s*=[^>]*)>.*?</style>#s',
 365                                 function ( $m ) use ( &$seen ) {
 366                                         $attr = Sanitizer::decodeTagAttributes( $m[1] );
 367                                         if ( !isset( $attr['data-mw-deduplicate'] ) ) {
 368                                                 return $m[0];
 369                                         }
 370
 371                                         $key = $attr['data-mw-deduplicate'];
 372                                         if ( !isset( $seen[$key] ) ) {
 373                                                 $seen[$key] = true;
 374                                                 return $m[0];
 375                                         }
 376
 377                                         // We were going to use an empty <style> here, but there
 378                                         // was concern that would be too much overhead for browsers.
 379                                         // So let's hope a <link> with a non-standard rel and href isn't
 380                                         // going to be misinterpreted or mangled by any subsequent processing.
 381                                         return Html::element( 'link', [
 382                                                 'rel' => 'mw-deduplicated-inline-style',
 383                                                 'href' => "mw-data:" . wfUrlencode( $key ),
 384                                         ] );
 385                                 },
 386                                 $text
 387                         );
 388                 }
 389
 390                 // Hydrate slot section header placeholders generated by RevisionRenderer.
 391                 $text = preg_replace_callback(
 392                         '#<mw:slotheader>(.*?)</mw:slotheader>#',
 393                         function ( $m ) {
 394                                 $role = htmlspecialchars_decode( $m[1] );
 395                                 // TODO: map to message, using the interface language. Set lang="xyz" accordingly.
 396                                 $headerText = $role;
 397                                 return $headerText;
 398                         },
 399                         $text
 400                 );
 401                 return $text;
 402         }
 403
 404         /**
 405          * Add a CSS class to use for the wrapping div. If no class is given, no wrapper is added.
 406          *
 407          * @param string $class
 408          */
 409         public function addWrapperDivClass( $class ) {
 410                 $this->mWrapperDivClasses[$class] = true;
 411         }
 412
 413         /**
 414          * Clears the CSS class to use for the wrapping div, effectively disabling the wrapper div
 415          * until addWrapperDivClass() is called.
 416          */
 417         public function clearWrapperDivClass() {
 418                 $this->mWrapperDivClasses = [];
 419         }
 420
 421         /**
 422          * Returns the class (or classes) to be used with the wrapper div for this otuput.
 423          * If there is no wrapper class given, no wrapper div should be added.
 424          * The wrapper div is added automatically by getText().
 425          *
 426          * @return string
 427          */
 428         public function getWrapperDivClass() {
 429                 return implode( ' ', array_keys( $this->mWrapperDivClasses ) );
 430         }
 431
 432         /**
 433          * @param int $id
 434          * @since 1.28
 435          */
 436         public function setSpeculativeRevIdUsed( $id ) {
 437                 $this->mSpeculativeRevId = $id;
 438         }
 439
 440         /**
 441          * @return int|null
 442          * @since 1.28
 443          */
 444         public function getSpeculativeRevIdUsed() {
 445                 return $this->mSpeculativeRevId;
 446         }
 447
 448         public function &getLanguageLinks() {
 449                 return $this->mLanguageLinks;
 450         }
 451
 452         public function getInterwikiLinks() {
 453                 return $this->mInterwikiLinks;
 454         }
 455
 456         public function getCategoryLinks() {
 457                 return array_keys( $this->mCategories );
 458         }
 459
 460         public function &getCategories() {
 461                 return $this->mCategories;
 462         }
 463
 464         /**
 465          * @return array
 466          * @since 1.25
 467          */
 468         public function getIndicators() {
 469                 return $this->mIndicators;
 470         }
 471
 472         public function getTitleText() {
 473                 return $this->mTitleText;
 474         }
 475
 476         public function getSections() {
 477                 return $this->mSections;
 478         }
 479
 480         public function &getLinks() {
 481                 return $this->mLinks;
 482         }
 483
 484         public function &getTemplates() {
 485                 return $this->mTemplates;
 486         }
 487
 488         public function &getTemplateIds() {
 489                 return $this->mTemplateIds;
 490         }
 491
 492         public function &getImages() {
 493                 return $this->mImages;
 494         }
 495
 496         public function &getFileSearchOptions() {
 497                 return $this->mFileSearchOptions;
 498         }
 499
 500         public function &getExternalLinks() {
 501                 return $this->mExternalLinks;
 502         }
 503
 504         public function setNoGallery( $value ) {
 505                 $this->mNoGallery = (bool)$value;
 506         }
 507
 508         public function getNoGallery() {
 509                 return $this->mNoGallery;
 510         }
 511
 512         public function getHeadItems() {
 513                 return $this->mHeadItems;
 514         }
 515
 516         public function getModules() {
 517                 return $this->mModules;
 518         }
 519
 520         public function getModuleStyles() {
 521                 return $this->mModuleStyles;
 522         }
 523
 524         /**
 525          * @return array
 526          * @since 1.23
 527          */
 528         public function getJsConfigVars() {
 529                 return $this->mJsConfigVars;
 530         }
 531
 532         public function getOutputHooks() {
 533                 return (array)$this->mOutputHooks;
 534         }
 535
 536         public function getWarnings() {
 537                 return array_keys( $this->mWarnings );
 538         }
 539
 540         public function getIndexPolicy() {
 541                 return $this->mIndexPolicy;
 542         }
 543
 544         public function getTOCHTML() {
 545                 return $this->mTOCHTML;
 546         }
 547
 548         /**
 549          * @return string|null TS_MW timestamp of the revision content
 550          */
 551         public function getTimestamp() {
 552                 return $this->mTimestamp;
 553         }
 554
 555         public function getLimitReportData() {
 556                 return $this->mLimitReportData;
 557         }
 558
 559         public function getLimitReportJSData() {
 560                 return $this->mLimitReportJSData;
 561         }
 562
 563         public function getEnableOOUI() {
 564                 return $this->mEnableOOUI;
 565         }
 566
 567         public function setText( $text ) {
 568                 return wfSetVar( $this->mText, $text );
 569         }
 570
 571         public function setLanguageLinks( $ll ) {
 572                 return wfSetVar( $this->mLanguageLinks, $ll );
 573         }
 574
 575         public function setCategoryLinks( $cl ) {
 576                 return wfSetVar( $this->mCategories, $cl );
 577         }
 578
 579         public function setTitleText( $t ) {
 580                 return wfSetVar( $this->mTitleText, $t );
 581         }
 582
 583         public function setSections( $toc ) {
 584                 return wfSetVar( $this->mSections, $toc );
 585         }
 586
 587         public function setIndexPolicy( $policy ) {
 588                 return wfSetVar( $this->mIndexPolicy, $policy );
 589         }
 590
 591         public function setTOCHTML( $tochtml ) {
 592                 return wfSetVar( $this->mTOCHTML, $tochtml );
 593         }
 594
 595         public function setTimestamp( $timestamp ) {
 596                 return wfSetVar( $this->mTimestamp, $timestamp );
 597         }
 598
 599         public function addCategory( $c, $sort ) {
 600                 $this->mCategories[$c] = $sort;
 601         }
 602
 603         /**
 604          * @param string $id
 605          * @param string $content
 606          * @since 1.25
 607          */
 608         public function setIndicator( $id, $content ) {
 609                 $this->mIndicators[$id] = $content;
 610         }
 611
 612         /**
 613          * Enables OOUI, if true, in any OutputPage instance this ParserOutput
 614          * object is added to.
 615          *
 616          * @since 1.26
 617          * @param bool $enable If OOUI should be enabled or not
 618          */
 619         public function setEnableOOUI( $enable = false ) {
 620                 $this->mEnableOOUI = $enable;
 621         }
 622
 623         public function addLanguageLink( $t ) {
 624                 $this->mLanguageLinks[] = $t;
 625         }
 626
 627         public function addWarning( $s ) {
 628                 $this->mWarnings[$s] = 1;
 629         }
 630
 631         public function addOutputHook( $hook, $data = false ) {
 632                 $this->mOutputHooks[] = [ $hook, $data ];
 633         }
 634
 635         public function setNewSection( $value ) {
 636                 $this->mNewSection = (bool)$value;
 637         }
 638
 639         public function hideNewSection( $value ) {
 640                 $this->mHideNewSection = (bool)$value;
 641         }
 642
 643         public function getHideNewSection() {
 644                 return (bool)$this->mHideNewSection;
 645         }
 646
 647         public function getNewSection() {
 648                 return (bool)$this->mNewSection;
 649         }
 650
 651         /**
 652          * Checks, if a url is pointing to the own server
 653          *
 654          * @param string $internal The server to check against
 655          * @param string $url The url to check
 656          * @return bool
 657          */
 658         public static function isLinkInternal( $internal, $url ) {
 659                 return (bool)preg_match( '/^' .
 660                         # If server is proto relative, check also for http/https links
 661                         ( substr( $internal, 0, 2 ) === '//' ? '(?:https?:)?' : '' ) .
 662                         preg_quote( $internal, '/' ) .
 663                         # check for query/path/anchor or end of link in each case
 664                         '(?:[\?\/\#]|$)/i',
 665                         $url
 666                 );
 667         }
 668
 669         public function addExternalLink( $url ) {
 670                 # We don't register links pointing to our own server, unless... :-)
 671                 global $wgServer, $wgRegisterInternalExternals;
 672
 673                 # Replace unnecessary URL escape codes with the referenced character
 674                 # This prevents spammers from hiding links from the filters
 675                 $url = Parser::normalizeLinkUrl( $url );
 676
 677                 $registerExternalLink = true;
 678                 if ( !$wgRegisterInternalExternals ) {
 679                         $registerExternalLink = !self::isLinkInternal( $wgServer, $url );
 680                 }
 681                 if ( $registerExternalLink ) {
 682                         $this->mExternalLinks[$url] = 1;
 683                 }
 684         }
 685
 686         /**
 687          * Record a local or interwiki inline link for saving in future link tables.
 688          *
 689          * @param Title $title
 690          * @param int|null $id Optional known page_id so we can skip the lookup
 691          */
 692         public function addLink( Title $title, $id = null ) {
 693                 if ( $title->isExternal() ) {
 694                         // Don't record interwikis in pagelinks
 695                         $this->addInterwikiLink( $title );
 696                         return;
 697                 }
 698                 $ns = $title->getNamespace();
 699                 $dbk = $title->getDBkey();
 700                 if ( $ns == NS_MEDIA ) {
 701                         // Normalize this pseudo-alias if it makes it down here...
 702                         $ns = NS_FILE;
 703                 } elseif ( $ns == NS_SPECIAL ) {
 704                         // We don't record Special: links currently
 705                         // It might actually be wise to, but we'd need to do some normalization.
 706                         return;
 707                 } elseif ( $dbk === '' ) {
 708                         // Don't record self links -  [[#Foo]]
 709                         return;
 710                 }
 711                 if ( !isset( $this->mLinks[$ns] ) ) {
 712                         $this->mLinks[$ns] = [];
 713                 }
 714                 if ( is_null( $id ) ) {
 715                         $id = $title->getArticleID();
 716                 }
 717                 $this->mLinks[$ns][$dbk] = $id;
 718         }
 719
 720         /**
 721          * Register a file dependency for this output
 722          * @param string $name Title dbKey
 723          * @param string|false|null $timestamp MW timestamp of file creation (or false if non-existing)
 724          * @param string|false|null $sha1 Base 36 SHA-1 of file (or false if non-existing)
 725          */
 726         public function addImage( $name, $timestamp = null, $sha1 = null ) {
 727                 $this->mImages[$name] = 1;
 728                 if ( $timestamp !== null && $sha1 !== null ) {
 729                         $this->mFileSearchOptions[$name] = [ 'time' => $timestamp, 'sha1' => $sha1 ];
 730                 }
 731         }
 732
 733         /**
 734          * Register a template dependency for this output
 735          * @param Title $title
 736          * @param int $page_id
 737          * @param int $rev_id
 738          */
 739         public function addTemplate( $title, $page_id, $rev_id ) {
 740                 $ns = $title->getNamespace();
 741                 $dbk = $title->getDBkey();
 742                 if ( !isset( $this->mTemplates[$ns] ) ) {
 743                         $this->mTemplates[$ns] = [];
 744                 }
 745                 $this->mTemplates[$ns][$dbk] = $page_id;
 746                 if ( !isset( $this->mTemplateIds[$ns] ) ) {
 747                         $this->mTemplateIds[$ns] = [];
 748                 }
 749                 $this->mTemplateIds[$ns][$dbk] = $rev_id; // For versioning
 750         }
 751
 752         /**
 753          * @param Title $title Title object, must be an interwiki link
 754          * @throws MWException If given invalid input
 755          */
 756         public function addInterwikiLink( $title ) {
 757                 if ( !$title->isExternal() ) {
 758                         throw new MWException( 'Non-interwiki link passed, internal parser error.' );
 759                 }
 760                 $prefix = $title->getInterwiki();
 761                 if ( !isset( $this->mInterwikiLinks[$prefix] ) ) {
 762                         $this->mInterwikiLinks[$prefix] = [];
 763                 }
 764                 $this->mInterwikiLinks[$prefix][$title->getDBkey()] = 1;
 765         }
 766
 767         /**
 768          * Add some text to the "<head>".
 769          * If $tag is set, the section with that tag will only be included once
 770          * in a given page.
 771          * @param string $section
 772          * @param string|bool $tag
 773          */
 774         public function addHeadItem( $section, $tag = false ) {
 775                 if ( $tag !== false ) {
 776                         $this->mHeadItems[$tag] = $section;
 777                 } else {
 778                         $this->mHeadItems[] = $section;
 779                 }
 780         }
 781
 782         /**
 783          * @see OutputPage::addModules
 784          */
 785         public function addModules( $modules ) {
 786                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 787         }
 788
 789         /**
 790          * @see OutputPage::addModuleStyles
 791          */
 792         public function addModuleStyles( $modules ) {
 793                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 794         }
 795
 796         /**
 797          * Add one or more variables to be set in mw.config in JavaScript.
 798          *
 799          * @param string|array $keys Key or array of key/value pairs.
 800          * @param mixed|null $value [optional] Value of the configuration variable.
 801          * @since 1.23
 802          */
 803         public function addJsConfigVars( $keys, $value = null ) {
 804                 if ( is_array( $keys ) ) {
 805                         foreach ( $keys as $key => $value ) {
 806                                 $this->mJsConfigVars[$key] = $value;
 807                         }
 808                         return;
 809                 }
 810
 811                 $this->mJsConfigVars[$keys] = $value;
 812         }
 813
 814         /**
 815          * Copy items from the OutputPage object into this one
 816          *
 817          * @param OutputPage $out
 818          */
 819         public function addOutputPageMetadata( OutputPage $out ) {
 820                 $this->addModules( $out->getModules() );
 821                 $this->addModuleStyles( $out->getModuleStyles() );
 822                 $this->addJsConfigVars( $out->getJsConfigVars() );
 823
 824                 $this->mHeadItems = array_merge( $this->mHeadItems, $out->getHeadItemsArray() );
 825                 $this->mPreventClickjacking = $this->mPreventClickjacking || $out->getPreventClickjacking();
 826         }
 827
 828         /**
 829          * Add a tracking category, getting the title from a system message,
 830          * or print a debug message if the title is invalid.
 831          *
 832          * Any message used with this function should be registered so it will
 833          * show up on Special:TrackingCategories. Core messages should be added
 834          * to SpecialTrackingCategories::$coreTrackingCategories, and extensions
 835          * should add to "TrackingCategories" in their extension.json.
 836          *
 837          * @todo Migrate some code to TrackingCategories
 838          *
 839          * @param string $msg Message key
 840          * @param Title $title title of the page which is being tracked
 841          * @return bool Whether the addition was successful
 842          * @since 1.25
 843          */
 844         public function addTrackingCategory( $msg, $title ) {
 845                 if ( $title->isSpecialPage() ) {
 846                         wfDebug( __METHOD__ . ": Not adding tracking category $msg to special page!\n" );
 847                         return false;
 848                 }
 849
 850                 // Important to parse with correct title (T33469)
 851                 $cat = wfMessage( $msg )
 852                         ->title( $title )
 853                         ->inContentLanguage()
 854                         ->text();
 855
 856                 # Allow tracking categories to be disabled by setting them to "-"
 857                 if ( $cat === '-' ) {
 858                         return false;
 859                 }
 860
 861                 $containerCategory = Title::makeTitleSafe( NS_CATEGORY, $cat );
 862                 if ( $containerCategory ) {
 863                         $this->addCategory( $containerCategory->getDBkey(), $this->getProperty( 'defaultsort' ) ?: '' );
 864                         return true;
 865                 } else {
 866                         wfDebug( __METHOD__ . ": [[MediaWiki:$msg]] is not a valid title!\n" );
 867                         return false;
 868                 }
 869         }
 870
 871         /**
 872          * Override the title to be used for display
 873          *
 874          * @note this is assumed to have been validated
 875          * (check equal normalisation, etc.)
 876          *
 877          * @note this is expected to be safe HTML,
 878          * ready to be served to the client.
 879          *
 880          * @param string $text Desired title text
 881          */
 882         public function setDisplayTitle( $text ) {
 883                 $this->setTitleText( $text );
 884                 $this->setProperty( 'displaytitle', $text );
 885         }
 886
 887         /**
 888          * Get the title to be used for display.
 889          *
 890          * As per the contract of setDisplayTitle(), this is safe HTML,
 891          * ready to be served to the client.
 892          *
 893          * @return string HTML
 894          */
 895         public function getDisplayTitle() {
 896                 $t = $this->getTitleText();
 897                 if ( $t === '' ) {
 898                         return false;
 899                 }
 900                 return $t;
 901         }
 902
 903         /**
 904          * Attach a flag to the output so that it can be checked later to handle special cases
 905          *
 906          * @param string $flag
 907          */
 908         public function setFlag( $flag ) {
 909                 $this->mFlags[$flag] = true;
 910         }
 911
 912         /**
 913          * @param string $flag
 914          * @return bool Whether the given flag was set to signify a special case
 915          */
 916         public function getFlag( $flag ) {
 917                 return isset( $this->mFlags[$flag] );
 918         }
 919
 920         /**
 921          * @return string[] List of flags signifying special cases
 922          * @since 1.34
 923          */
 924         public function getAllFlags() {
 925                 return array_keys( $this->mFlags );
 926         }
 927
 928         /**
 929          * Set a property to be stored in the page_props database table.
 930          *
 931          * page_props is a key value store indexed by the page ID. This allows
 932          * the parser to set a property on a page which can then be quickly
 933          * retrieved given the page ID or via a DB join when given the page
 934          * title.
 935          *
 936          * Since 1.23, page_props are also indexed by numeric value, to allow
 937          * for efficient "top k" queries of pages wrt a given property.
 938          *
 939          * setProperty() is thus used to propagate properties from the parsed
 940          * page to request contexts other than a page view of the currently parsed
 941          * article.
 942          *
 943          * Some applications examples:
 944          *
 945          *   * To implement hidden categories, hiding pages from category listings
 946          *     by storing a property.
 947          *
 948          *   * Overriding the displayed article title (ParserOutput::setDisplayTitle()).
 949          *
 950          *   * To implement image tagging, for example displaying an icon on an
 951          *     image thumbnail to indicate that it is listed for deletion on
 952          *     Wikimedia Commons.
 953          *     This is not actually implemented, yet but would be pretty cool.
 954          *
 955          * @note Do not use setProperty() to set a property which is only used
 956          * in a context where the ParserOutput object itself is already available,
 957          * for example a normal page view. There is no need to save such a property
 958          * in the database since the text is already parsed. You can just hook
 959          * OutputPageParserOutput and get your data out of the ParserOutput object.
 960          *
 961          * If you are writing an extension where you want to set a property in the
 962          * parser which is used by an OutputPageParserOutput hook, you have to
 963          * associate the extension data directly with the ParserOutput object.
 964          * Since MediaWiki 1.21, you can use setExtensionData() to do this:
 965          *
 966          * @par Example:
 967          * @code
 968          *    $parser->getOutput()->setExtensionData( 'my_ext_foo', '...' );
 969          * @endcode
 970          *
 971          * And then later, in OutputPageParserOutput or similar:
 972          *
 973          * @par Example:
 974          * @code
 975          *    $output->getExtensionData( 'my_ext_foo' );
 976          * @endcode
 977          *
 978          * In MediaWiki 1.20 and older, you have to use a custom member variable
 979          * within the ParserOutput object:
 980          *
 981          * @par Example:
 982          * @code
 983          *    $parser->getOutput()->my_ext_foo = '...';
 984          * @endcode
 985          * @param string $name
 986          * @param mixed $value
 987          */
 988         public function setProperty( $name, $value ) {
 989                 $this->mProperties[$name] = $value;
 990         }
 991
 992         /**
 993          * @param string $name The property name to look up.
 994          *
 995          * @return mixed|bool The value previously set using setProperty(). False if null or no value
 996          * was set for the given property name.
 997          *
 998          * @note You need to use getProperties() to check for boolean and null properties.
 999          */
1000         public function getProperty( $name ) {
1001                 return $this->mProperties[$name] ?? false;
1002         }
1003
1004         public function unsetProperty( $name ) {
1005                 unset( $this->mProperties[$name] );
1006         }
1007
1008         public function getProperties() {
1009                 if ( !isset( $this->mProperties ) ) {
1010                         $this->mProperties = [];
1011                 }
1012                 return $this->mProperties;
1013         }
1014
1015         /**
1016          * Returns the options from its ParserOptions which have been taken
1017          * into account to produce this output.
1018          * @return string[]
1019          */
1020         public function getUsedOptions() {
1021                 if ( !isset( $this->mAccessedOptions ) ) {
1022                         return [];
1023                 }
1024                 return array_keys( $this->mAccessedOptions );
1025         }
1026
1027         /**
1028          * Tags a parser option for use in the cache key for this parser output.
1029          * Registered as a watcher at ParserOptions::registerWatcher() by Parser::clearState().
1030          * The information gathered here is available via getUsedOptions(),
1031          * and is used by ParserCache::save().
1032          *
1033          * @see ParserCache::getKey
1034          * @see ParserCache::save
1035          * @see ParserOptions::addExtraKey
1036          * @see ParserOptions::optionsHash
1037          * @param string $option
1038          */
1039         public function recordOption( $option ) {
1040                 $this->mAccessedOptions[$option] = true;
1041         }
1042
1043         /**
1044          * Attaches arbitrary data to this ParserObject. This can be used to store some information in
1045          * the ParserOutput object for later use during page output. The data will be cached along with
1046          * the ParserOutput object, but unlike data set using setProperty(), it is not recorded in the
1047          * database.
1048          *
1049          * This method is provided to overcome the unsafe practice of attaching extra information to a
1050          * ParserObject by directly assigning member variables.
1051          *
1052          * To use setExtensionData() to pass extension information from a hook inside the parser to a
1053          * hook in the page output, use this in the parser hook:
1054          *
1055          * @par Example:
1056          * @code
1057          *    $parser->getOutput()->setExtensionData( 'my_ext_foo', '...' );
1058          * @endcode
1059          *
1060          * And then later, in OutputPageParserOutput or similar:
1061          *
1062          * @par Example:
1063          * @code
1064          *    $output->getExtensionData( 'my_ext_foo' );
1065          * @endcode
1066          *
1067          * In MediaWiki 1.20 and older, you have to use a custom member variable
1068          * within the ParserOutput object:
1069          *
1070          * @par Example:
1071          * @code
1072          *    $parser->getOutput()->my_ext_foo = '...';
1073          * @endcode
1074          *
1075          * @since 1.21
1076          *
1077          * @param string $key The key for accessing the data. Extensions should take care to avoid
1078          *   conflicts in naming keys. It is suggested to use the extension's name as a prefix.
1079          *
1080          * @param mixed $value The value to set. Setting a value to null is equivalent to removing
1081          *   the value.
1082          */
1083         public function setExtensionData( $key, $value ) {
1084                 if ( $value === null ) {
1085                         unset( $this->mExtensionData[$key] );
1086                 } else {
1087                         $this->mExtensionData[$key] = $value;
1088                 }
1089         }
1090
1091         /**
1092          * Gets extensions data previously attached to this ParserOutput using setExtensionData().
1093          * Typically, such data would be set while parsing the page, e.g. by a parser function.
1094          *
1095          * @since 1.21
1096          *
1097          * @param string $key The key to look up.
1098          *
1099          * @return mixed|null The value previously set for the given key using setExtensionData()
1100          *         or null if no value was set for this key.
1101          */
1102         public function getExtensionData( $key ) {
1103                 return $this->mExtensionData[$key] ?? null;
1104         }
1105
1106         private static function getTimes( $clock = null ) {
1107                 $ret = [];
1108                 if ( !$clock || $clock === 'wall' ) {
1109                         $ret['wall'] = microtime( true );
1110                 }
1111                 if ( !$clock || $clock === 'cpu' ) {
1112                         $ru = wfGetRusage();
1113                         if ( $ru ) {
1114                                 $ret['cpu'] = $ru['ru_utime.tv_sec'] + $ru['ru_utime.tv_usec'] / 1e6;
1115                                 $ret['cpu'] += $ru['ru_stime.tv_sec'] + $ru['ru_stime.tv_usec'] / 1e6;
1116                         }
1117                 }
1118                 return $ret;
1119         }
1120
1121         /**
1122          * Resets the parse start timestamps for future calls to getTimeSinceStart()
1123          * @since 1.22
1124          */
1125         public function resetParseStartTime() {
1126                 $this->mParseStartTime = self::getTimes();
1127         }
1128
1129         /**
1130          * Returns the time since resetParseStartTime() was last called
1131          *
1132          * Clocks available are:
1133          *  - wall: Wall clock time
1134          *  - cpu: CPU time (requires getrusage)
1135          *
1136          * @since 1.22
1137          * @param string $clock
1138          * @return float|null
1139          */
1140         public function getTimeSinceStart( $clock ) {
1141                 if ( !isset( $this->mParseStartTime[$clock] ) ) {
1142                         return null;
1143                 }
1144
1145                 $end = self::getTimes( $clock );
1146                 return $end[$clock] - $this->mParseStartTime[$clock];
1147         }
1148
1149         /**
1150          * Sets parser limit report data for a key
1151          *
1152          * The key is used as the prefix for various messages used for formatting:
1153          *  - $key: The label for the field in the limit report
1154          *  - $key-value-text: Message used to format the value in the "NewPP limit
1155          *      report" HTML comment. If missing, uses $key-format.
1156          *  - $key-value-html: Message used to format the value in the preview
1157          *      limit report table. If missing, uses $key-format.
1158          *  - $key-value: Message used to format the value. If missing, uses "$1".
1159          *
1160          * Note that all values are interpreted as wikitext, and so should be
1161          * encoded with htmlspecialchars() as necessary, but should avoid complex
1162          * HTML for sanity of display in the "NewPP limit report" comment.
1163          *
1164          * @since 1.22
1165          * @param string $key Message key
1166          * @param mixed $value Appropriate for Message::params()
1167          */
1168         public function setLimitReportData( $key, $value ) {
1169                 $this->mLimitReportData[$key] = $value;
1170
1171                 if ( is_array( $value ) ) {
1172                         if ( array_keys( $value ) === [ 0, 1 ]
1173                                 && is_numeric( $value[0] )
1174                                 && is_numeric( $value[1] )
1175                         ) {
1176                                 $data = [ 'value' => $value[0], 'limit' => $value[1] ];
1177                         } else {
1178                                 $data = $value;
1179                         }
1180                 } else {
1181                         $data = $value;
1182                 }
1183
1184                 if ( strpos( $key, '-' ) ) {
1185                         list( $ns, $name ) = explode( '-', $key, 2 );
1186                         $this->mLimitReportJSData[$ns][$name] = $data;
1187                 } else {
1188                         $this->mLimitReportJSData[$key] = $data;
1189                 }
1190         }
1191
1192         /**
1193          * Check whether the cache TTL was lowered due to dynamic content
1194          *
1195          * When content is determined by more than hard state (e.g. page edits),
1196          * such as template/file transclusions based on the current timestamp or
1197          * extension tags that generate lists based on queries, this return true.
1198          *
1199          * @return bool
1200          * @since 1.25
1201          */
1202         public function hasDynamicContent() {
1203                 global $wgParserCacheExpireTime;
1204
1205                 return $this->getCacheExpiry() < $wgParserCacheExpireTime;
1206         }
1207
1208         /**
1209          * Get or set the prevent-clickjacking flag
1210          *
1211          * @since 1.24
1212          * @param bool|null $flag New flag value, or null to leave it unchanged
1213          * @return bool Old flag value
1214          */
1215         public function preventClickjacking( $flag = null ) {
1216                 return wfSetVar( $this->mPreventClickjacking, $flag );
1217         }
1218
1219         /**
1220          * Lower the runtime adaptive TTL to at most this value
1221          *
1222          * @param int $ttl
1223          * @since 1.28
1224          */
1225         public function updateRuntimeAdaptiveExpiry( $ttl ) {
1226                 $this->mMaxAdaptiveExpiry = min( $ttl, $this->mMaxAdaptiveExpiry );
1227                 $this->updateCacheExpiry( $ttl );
1228         }
1229
1230         /**
1231          * Call this when parsing is done to lower the TTL based on low parse times
1232          *
1233          * @since 1.28
1234          */
1235         public function finalizeAdaptiveCacheExpiry() {
1236                 if ( is_infinite( $this->mMaxAdaptiveExpiry ) ) {
1237                         return; // not set
1238                 }
1239
1240                 $runtime = $this->getTimeSinceStart( 'wall' );
1241                 if ( is_float( $runtime ) ) {
1242                         $slope = ( self::SLOW_AR_TTL - self::FAST_AR_TTL )
1243                                 / ( self::PARSE_SLOW_SEC - self::PARSE_FAST_SEC );
1244                         // SLOW_AR_TTL = PARSE_SLOW_SEC * $slope + $point
1245                         $point = self::SLOW_AR_TTL - self::PARSE_SLOW_SEC * $slope;
1246
1247                         $adaptiveTTL = min(
1248                                 max( $slope * $runtime + $point, self::MIN_AR_TTL ),
1249                                 $this->mMaxAdaptiveExpiry
1250                         );
1251                         $this->updateCacheExpiry( $adaptiveTTL );
1252                 }
1253         }
1254
1255         public function __sleep() {
1256                 return array_diff(
1257                         array_keys( get_object_vars( $this ) ),
1258                         [ 'mParseStartTime' ]
1259                 );
1260         }
1261
1262         /**
1263          * Merges internal metadata such as flags, accessed options, and profiling info
1264          * from $source into this ParserOutput. This should be used whenever the state of $source
1265          * has any impact on the state of this ParserOutput.
1266          *
1267          * @param ParserOutput $source
1268          */
1269         public function mergeInternalMetaDataFrom( ParserOutput $source ) {
1270                 $this->mOutputHooks = self::mergeList( $this->mOutputHooks, $source->getOutputHooks() );
1271                 $this->mWarnings = self::mergeMap( $this->mWarnings, $source->mWarnings ); // don't use getter
1272                 $this->mTimestamp = $this->useMaxValue( $this->mTimestamp, $source->getTimestamp() );
1273
1274                 if ( $this->mSpeculativeRevId && $source->mSpeculativeRevId
1275                         && $this->mSpeculativeRevId !== $source->mSpeculativeRevId
1276                 ) {
1277                         wfLogWarning(
1278                                 'Inconsistent speculative revision ID encountered while merging parser output!'
1279                         );
1280                 }
1281
1282                 $this->mSpeculativeRevId = $this->useMaxValue(
1283                         $this->mSpeculativeRevId,
1284                         $source->getSpeculativeRevIdUsed()
1285                 );
1286                 $this->mParseStartTime = $this->useEachMinValue(
1287                         $this->mParseStartTime,
1288                         $source->mParseStartTime
1289                 );
1290
1291                 $this->mFlags = self::mergeMap( $this->mFlags, $source->mFlags );
1292                 $this->mAccessedOptions = self::mergeMap( $this->mAccessedOptions, $source->mAccessedOptions );
1293
1294                 // TODO: maintain per-slot limit reports!
1295                 if ( empty( $this->mLimitReportData ) ) {
1296                         $this->mLimitReportData = $source->mLimitReportData;
1297                 }
1298                 if ( empty( $this->mLimitReportJSData ) ) {
1299                         $this->mLimitReportJSData = $source->mLimitReportJSData;
1300                 }
1301         }
1302
1303         /**
1304          * Merges HTML metadata such as head items, JS config vars, and HTTP cache control info
1305          * from $source into this ParserOutput. This should be used whenever the HTML in $source
1306          * has been somehow mered into the HTML of this ParserOutput.
1307          *
1308          * @param ParserOutput $source
1309          */
1310         public function mergeHtmlMetaDataFrom( ParserOutput $source ) {
1311                 // HTML and HTTP
1312                 $this->mHeadItems = self::mergeMixedList( $this->mHeadItems, $source->getHeadItems() );
1313                 $this->mModules = self::mergeList( $this->mModules, $source->getModules() );
1314                 $this->mModuleStyles = self::mergeList( $this->mModuleStyles, $source->getModuleStyles() );
1315                 $this->mJsConfigVars = self::mergeMap( $this->mJsConfigVars, $source->getJsConfigVars() );
1316                 $this->mMaxAdaptiveExpiry = min( $this->mMaxAdaptiveExpiry, $source->mMaxAdaptiveExpiry );
1317
1318                 // "noindex" always wins!
1319                 if ( $this->mIndexPolicy === 'noindex' || $source->mIndexPolicy === 'noindex' ) {
1320                         $this->mIndexPolicy = 'noindex';
1321                 } elseif ( $this->mIndexPolicy !== 'index' ) {
1322                         $this->mIndexPolicy = $source->mIndexPolicy;
1323                 }
1324
1325                 // Skin control
1326                 $this->mNewSection = $this->mNewSection || $source->getNewSection();
1327                 $this->mHideNewSection = $this->mHideNewSection || $source->getHideNewSection();
1328                 $this->mNoGallery = $this->mNoGallery || $source->getNoGallery();
1329                 $this->mEnableOOUI = $this->mEnableOOUI || $source->getEnableOOUI();
1330                 $this->mPreventClickjacking = $this->mPreventClickjacking || $source->preventClickjacking();
1331
1332                 // TODO: we'll have to be smarter about this!
1333                 $this->mSections = array_merge( $this->mSections, $source->getSections() );
1334                 $this->mTOCHTML .= $source->mTOCHTML;
1335
1336                 // XXX: we don't want to concatenate title text, so first write wins.
1337                 // We should use the first *modified* title text, but we don't have the original to check.
1338                 if ( $this->mTitleText === null || $this->mTitleText === '' ) {
1339                         $this->mTitleText = $source->mTitleText;
1340                 }
1341
1342                 // class names are stored in array keys
1343                 $this->mWrapperDivClasses = self::mergeMap(
1344                         $this->mWrapperDivClasses,
1345                         $source->mWrapperDivClasses
1346                 );
1347
1348                 // NOTE: last write wins, same as within one ParserOutput
1349                 $this->mIndicators = self::mergeMap( $this->mIndicators, $source->getIndicators() );
1350
1351                 // NOTE: include extension data in "tracking meta data" as well as "html meta data"!
1352                 // TODO: add a $mergeStrategy parameter to setExtensionData to allow different
1353                 // kinds of extension data to be merged in different ways.
1354                 $this->mExtensionData = self::mergeMap(
1355                         $this->mExtensionData,
1356                         $source->mExtensionData
1357                 );
1358         }
1359
1360         /**
1361          * Merges dependency tracking metadata such as backlinks, images used, and extension data
1362          * from $source into this ParserOutput. This allows dependency tracking to be done for the
1363          * combined output of multiple content slots.
1364          *
1365          * @param ParserOutput $source
1366          */
1367         public function mergeTrackingMetaDataFrom( ParserOutput $source ) {
1368                 $this->mLanguageLinks = self::mergeList( $this->mLanguageLinks, $source->getLanguageLinks() );
1369                 $this->mCategories = self::mergeMap( $this->mCategories, $source->getCategories() );
1370                 $this->mLinks = self::merge2D( $this->mLinks, $source->getLinks() );
1371                 $this->mTemplates = self::merge2D( $this->mTemplates, $source->getTemplates() );
1372                 $this->mTemplateIds = self::merge2D( $this->mTemplateIds, $source->getTemplateIds() );
1373                 $this->mImages = self::mergeMap( $this->mImages, $source->getImages() );
1374                 $this->mFileSearchOptions = self::mergeMap(
1375                         $this->mFileSearchOptions,
1376                         $source->getFileSearchOptions()
1377                 );
1378                 $this->mExternalLinks = self::mergeMap( $this->mExternalLinks, $source->getExternalLinks() );
1379                 $this->mInterwikiLinks = self::merge2D(
1380                         $this->mInterwikiLinks,
1381                         $source->getInterwikiLinks()
1382                 );
1383
1384                 // TODO: add a $mergeStrategy parameter to setProperty to allow different
1385                 // kinds of properties to be merged in different ways.
1386                 $this->mProperties = self::mergeMap( $this->mProperties, $source->getProperties() );
1387
1388                 // NOTE: include extension data in "tracking meta data" as well as "html meta data"!
1389                 // TODO: add a $mergeStrategy parameter to setExtensionData to allow different
1390                 // kinds of extension data to be merged in different ways.
1391                 $this->mExtensionData = self::mergeMap(
1392                         $this->mExtensionData,
1393                         $source->mExtensionData
1394                 );
1395         }
1396
1397         private static function mergeMixedList( array $a, array $b ) {
1398                 return array_unique( array_merge( $a, $b ), SORT_REGULAR );
1399         }
1400
1401         private static function mergeList( array $a, array $b ) {
1402                 return array_values( array_unique( array_merge( $a, $b ), SORT_REGULAR ) );
1403         }
1404
1405         private static function mergeMap( array $a, array $b ) {
1406                 return array_replace( $a, $b );
1407         }
1408
1409         private static function merge2D( array $a, array $b ) {
1410                 $values = [];
1411                 $keys = array_merge( array_keys( $a ), array_keys( $b ) );
1412
1413                 foreach ( $keys as $k ) {
1414                         if ( empty( $a[$k] ) ) {
1415                                 $values[$k] = $b[$k];
1416                         } elseif ( empty( $b[$k] ) ) {
1417                                 $values[$k] = $a[$k];
1418                         } elseif ( is_array( $a[$k] ) && is_array( $b[$k] ) ) {
1419                                 $values[$k] = array_replace( $a[$k], $b[$k] );
1420                         } else {
1421                                 $values[$k] = $b[$k];
1422                         }
1423                 }
1424
1425                 return $values;
1426         }
1427
1428         private static function useEachMinValue( array $a, array $b ) {
1429                 $values = [];
1430                 $keys = array_merge( array_keys( $a ), array_keys( $b ) );
1431
1432                 foreach ( $keys as $k ) {
1433                         if ( is_array( $a[$k] ?? null ) && is_array( $b[$k] ?? null ) ) {
1434                                 $values[$k] = self::useEachMinValue( $a[$k], $b[$k] );
1435                         } else {
1436                                 $values[$k] = self::useMinValue( $a[$k] ?? null, $b[$k] ?? null );
1437                         }
1438                 }
1439
1440                 return $values;
1441         }
1442
1443         private static function useMinValue( $a, $b ) {
1444                 if ( $a === null ) {
1445                         return $b;
1446                 }
1447
1448                 if ( $b === null ) {
1449                         return $a;
1450                 }
1451
1452                 return min( $a, $b );
1453         }
1454
1455         private static function useMaxValue( $a, $b ) {
1456                 if ( $a === null ) {
1457                         return $b;
1458                 }
1459
1460                 if ( $b === null ) {
1461                         return $a;
1462                 }
1463
1464                 return max( $a, $b );
1465         }
1466
1467 }