includes/parser/Preprocessor_DOM.php

   1 <?php
   2 /**
   3  * Preprocessor using PHP's dom extension
   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  * @ingroup Parser
  26  */
  27 // phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
  28 class Preprocessor_DOM extends Preprocessor {
  29
  30         /**
  31          * @var Parser
  32          */
  33         public $parser;
  34
  35         public $memoryLimit;
  36
  37         const CACHE_PREFIX = 'preprocess-xml';
  38
  39         public function __construct( $parser ) {
  40                 $this->parser = $parser;
  41                 $mem = ini_get( 'memory_limit' );
  42                 $this->memoryLimit = false;
  43                 if ( strval( $mem ) !== '' && $mem != -1 ) {
  44                         if ( preg_match( '/^\d+$/', $mem ) ) {
  45                                 $this->memoryLimit = $mem;
  46                         } elseif ( preg_match( '/^(\d+)M$/i', $mem, $m ) ) {
  47                                 $this->memoryLimit = $m[1] * 1048576;
  48                         }
  49                 }
  50         }
  51
  52         /**
  53          * @return PPFrame_DOM
  54          */
  55         public function newFrame() {
  56                 return new PPFrame_DOM( $this );
  57         }
  58
  59         /**
  60          * @param array $args
  61          * @return PPCustomFrame_DOM
  62          */
  63         public function newCustomFrame( $args ) {
  64                 return new PPCustomFrame_DOM( $this, $args );
  65         }
  66
  67         /**
  68          * @param array $values
  69          * @return PPNode_DOM
  70          * @throws MWException
  71          */
  72         public function newPartNodeArray( $values ) {
  73                 // NOTE: DOM manipulation is slower than building & parsing XML! (or so Tim sais)
  74                 $xml = "<list>";
  75
  76                 foreach ( $values as $k => $val ) {
  77                         if ( is_int( $k ) ) {
  78                                 $xml .= "<part><name index=\"$k\"/><value>"
  79                                         . htmlspecialchars( $val ) . "</value></part>";
  80                         } else {
  81                                 $xml .= "<part><name>" . htmlspecialchars( $k )
  82                                         . "</name>=<value>" . htmlspecialchars( $val ) . "</value></part>";
  83                         }
  84                 }
  85
  86                 $xml .= "</list>";
  87
  88                 $dom = new DOMDocument();
  89                 Wikimedia\suppressWarnings();
  90                 $result = $dom->loadXML( $xml );
  91                 Wikimedia\restoreWarnings();
  92                 if ( !$result ) {
  93                         // Try running the XML through UtfNormal to get rid of invalid characters
  94                         $xml = UtfNormal\Validator::cleanUp( $xml );
  95                         // 1 << 19 == XML_PARSE_HUGE, needed so newer versions of libxml2
  96                         // don't barf when the XML is >256 levels deep
  97                         $result = $dom->loadXML( $xml, 1 << 19 );
  98                 }
  99
 100                 if ( !$result ) {
 101                         throw new MWException( 'Parameters passed to ' . __METHOD__ . ' result in invalid XML' );
 102                 }
 103
 104                 $root = $dom->documentElement;
 105                 $node = new PPNode_DOM( $root->childNodes );
 106                 return $node;
 107         }
 108
 109         /**
 110          * @throws MWException
 111          * @return bool
 112          */
 113         public function memCheck() {
 114                 if ( $this->memoryLimit === false ) {
 115                         return true;
 116                 }
 117                 $usage = memory_get_usage();
 118                 if ( $usage > $this->memoryLimit * 0.9 ) {
 119                         $limit = intval( $this->memoryLimit * 0.9 / 1048576 + 0.5 );
 120                         throw new MWException( "Preprocessor hit 90% memory limit ($limit MB)" );
 121                 }
 122                 return $usage <= $this->memoryLimit * 0.8;
 123         }
 124
 125         /**
 126          * Preprocess some wikitext and return the document tree.
 127          * This is the ghost of Parser::replace_variables().
 128          *
 129          * @param string $text The text to parse
 130          * @param int $flags Bitwise combination of:
 131          *     Parser::PTD_FOR_INCLUSION  Handle "<noinclude>" and "<includeonly>"
 132          *                                as if the text is being included. Default
 133          *                                is to assume a direct page view.
 134          *
 135          * The generated DOM tree must depend only on the input text and the flags.
 136          * The DOM tree must be the same in OT_HTML and OT_WIKI mode, to avoid a regression of T6899.
 137          *
 138          * Any flag added to the $flags parameter here, or any other parameter liable to cause a
 139          * change in the DOM tree for a given text, must be passed through the section identifier
 140          * in the section edit link and thus back to extractSections().
 141          *
 142          * The output of this function is currently only cached in process memory, but a persistent
 143          * cache may be implemented at a later date which takes further advantage of these strict
 144          * dependency requirements.
 145          *
 146          * @throws MWException
 147          * @return PPNode_DOM
 148          */
 149         public function preprocessToObj( $text, $flags = 0 ) {
 150                 $xml = $this->cacheGetTree( $text, $flags );
 151                 if ( $xml === false ) {
 152                         $xml = $this->preprocessToXml( $text, $flags );
 153                         $this->cacheSetTree( $text, $flags, $xml );
 154                 }
 155
 156                 // Fail if the number of elements exceeds acceptable limits
 157                 // Do not attempt to generate the DOM
 158                 $this->parser->mGeneratedPPNodeCount += substr_count( $xml, '<' );
 159                 $max = $this->parser->mOptions->getMaxGeneratedPPNodeCount();
 160                 if ( $this->parser->mGeneratedPPNodeCount > $max ) {
 161                         // if ( $cacheable ) { ... }
 162                         throw new MWException( __METHOD__ . ': generated node count limit exceeded' );
 163                 }
 164
 165                 $dom = new DOMDocument;
 166                 Wikimedia\suppressWarnings();
 167                 $result = $dom->loadXML( $xml );
 168                 Wikimedia\restoreWarnings();
 169                 if ( !$result ) {
 170                         // Try running the XML through UtfNormal to get rid of invalid characters
 171                         $xml = UtfNormal\Validator::cleanUp( $xml );
 172                         // 1 << 19 == XML_PARSE_HUGE, needed so newer versions of libxml2
 173                         // don't barf when the XML is >256 levels deep.
 174                         $result = $dom->loadXML( $xml, 1 << 19 );
 175                 }
 176                 if ( $result ) {
 177                         $obj = new PPNode_DOM( $dom->documentElement );
 178                 }
 179
 180                 // if ( $cacheable ) { ... }
 181
 182                 if ( !$result ) {
 183                         throw new MWException( __METHOD__ . ' generated invalid XML' );
 184                 }
 185                 return $obj;
 186         }
 187
 188         /**
 189          * @param string $text
 190          * @param int $flags
 191          * @return string
 192          */
 193         public function preprocessToXml( $text, $flags = 0 ) {
 194                 global $wgDisableLangConversion;
 195
 196                 $forInclusion = $flags & Parser::PTD_FOR_INCLUSION;
 197
 198                 $xmlishElements = $this->parser->getStripList();
 199                 $xmlishAllowMissingEndTag = [ 'includeonly', 'noinclude', 'onlyinclude' ];
 200                 $enableOnlyinclude = false;
 201                 if ( $forInclusion ) {
 202                         $ignoredTags = [ 'includeonly', '/includeonly' ];
 203                         $ignoredElements = [ 'noinclude' ];
 204                         $xmlishElements[] = 'noinclude';
 205                         if ( strpos( $text, '<onlyinclude>' ) !== false
 206                                 && strpos( $text, '</onlyinclude>' ) !== false
 207                         ) {
 208                                 $enableOnlyinclude = true;
 209                         }
 210                 } else {
 211                         $ignoredTags = [ 'noinclude', '/noinclude', 'onlyinclude', '/onlyinclude' ];
 212                         $ignoredElements = [ 'includeonly' ];
 213                         $xmlishElements[] = 'includeonly';
 214                 }
 215                 $xmlishRegex = implode( '|', array_merge( $xmlishElements, $ignoredTags ) );
 216
 217                 // Use "A" modifier (anchored) instead of "^", because ^ doesn't work with an offset
 218                 $elementsRegex = "~($xmlishRegex)(?:\s|\/>|>)|(!--)~iA";
 219
 220                 $stack = new PPDStack;
 221
 222                 $searchBase = "[{<\n"; # }
 223                 if ( !$wgDisableLangConversion ) {
 224                         $searchBase .= '-';
 225                 }
 226
 227                 // For fast reverse searches
 228                 $revText = strrev( $text );
 229                 $lengthText = strlen( $text );
 230
 231                 // Input pointer, starts out pointing to a pseudo-newline before the start
 232                 $i = 0;
 233                 // Current accumulator
 234                 $accum =& $stack->getAccum();
 235                 $accum = '<root>';
 236                 // True to find equals signs in arguments
 237                 $findEquals = false;
 238                 // True to take notice of pipe characters
 239                 $findPipe = false;
 240                 $headingIndex = 1;
 241                 // True if $i is inside a possible heading
 242                 $inHeading = false;
 243                 // True if there are no more greater-than (>) signs right of $i
 244                 $noMoreGT = false;
 245                 // Map of tag name => true if there are no more closing tags of given type right of $i
 246                 $noMoreClosingTag = [];
 247                 // True to ignore all input up to the next <onlyinclude>
 248                 $findOnlyinclude = $enableOnlyinclude;
 249                 // Do a line-start run without outputting an LF character
 250                 $fakeLineStart = true;
 251
 252                 while ( true ) {
 253                         // $this->memCheck();
 254
 255                         if ( $findOnlyinclude ) {
 256                                 // Ignore all input up to the next <onlyinclude>
 257                                 $startPos = strpos( $text, '<onlyinclude>', $i );
 258                                 if ( $startPos === false ) {
 259                                         // Ignored section runs to the end
 260                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i ) ) . '</ignore>';
 261                                         break;
 262                                 }
 263                                 $tagEndPos = $startPos + strlen( '<onlyinclude>' ); // past-the-end
 264                                 $accum .= '<ignore>' . htmlspecialchars( substr( $text, $i, $tagEndPos - $i ) ) . '</ignore>';
 265                                 $i = $tagEndPos;
 266                                 $findOnlyinclude = false;
 267                         }
 268
 269                         if ( $fakeLineStart ) {
 270                                 $found = 'line-start';
 271                                 $curChar = '';
 272                         } else {
 273                                 # Find next opening brace, closing brace or pipe
 274                                 $search = $searchBase;
 275                                 if ( $stack->top === false ) {
 276                                         $currentClosing = '';
 277                                 } else {
 278                                         $currentClosing = $stack->top->close;
 279                                         $search .= $currentClosing;
 280                                 }
 281                                 if ( $findPipe ) {
 282                                         $search .= '|';
 283                                 }
 284                                 if ( $findEquals ) {
 285                                         // First equals will be for the template
 286                                         $search .= '=';
 287                                 }
 288                                 $rule = null;
 289                                 # Output literal section, advance input counter
 290                                 $literalLength = strcspn( $text, $search, $i );
 291                                 if ( $literalLength > 0 ) {
 292                                         $accum .= htmlspecialchars( substr( $text, $i, $literalLength ) );
 293                                         $i += $literalLength;
 294                                 }
 295                                 if ( $i >= $lengthText ) {
 296                                         if ( $currentClosing == "\n" ) {
 297                                                 // Do a past-the-end run to finish off the heading
 298                                                 $curChar = '';
 299                                                 $found = 'line-end';
 300                                         } else {
 301                                                 # All done
 302                                                 break;
 303                                         }
 304                                 } else {
 305                                         $curChar = $curTwoChar = $text[$i];
 306                                         if ( ( $i + 1 ) < $lengthText ) {
 307                                                 $curTwoChar .= $text[$i + 1];
 308                                         }
 309                                         if ( $curChar == '|' ) {
 310                                                 $found = 'pipe';
 311                                         } elseif ( $curChar == '=' ) {
 312                                                 $found = 'equals';
 313                                         } elseif ( $curChar == '<' ) {
 314                                                 $found = 'angle';
 315                                         } elseif ( $curChar == "\n" ) {
 316                                                 if ( $inHeading ) {
 317                                                         $found = 'line-end';
 318                                                 } else {
 319                                                         $found = 'line-start';
 320                                                 }
 321                                         } elseif ( $curTwoChar == $currentClosing ) {
 322                                                 $found = 'close';
 323                                                 $curChar = $curTwoChar;
 324                                         } elseif ( $curChar == $currentClosing ) {
 325                                                 $found = 'close';
 326                                         } elseif ( isset( $this->rules[$curTwoChar] ) ) {
 327                                                 $curChar = $curTwoChar;
 328                                                 $found = 'open';
 329                                                 $rule = $this->rules[$curChar];
 330                                         } elseif ( isset( $this->rules[$curChar] ) ) {
 331                                                 $found = 'open';
 332                                                 $rule = $this->rules[$curChar];
 333                                         } else {
 334                                                 # Some versions of PHP have a strcspn which stops on
 335                                                 # null characters; ignore these and continue.
 336                                                 # We also may get '-' and '}' characters here which
 337                                                 # don't match -{ or $currentClosing.  Add these to
 338                                                 # output and continue.
 339                                                 if ( $curChar == '-' || $curChar == '}' ) {
 340                                                         $accum .= $curChar;
 341                                                 }
 342                                                 ++$i;
 343                                                 continue;
 344                                         }
 345                                 }
 346                         }
 347
 348                         if ( $found == 'angle' ) {
 349                                 $matches = false;
 350                                 // Handle </onlyinclude>
 351                                 if ( $enableOnlyinclude
 352                                         && substr( $text, $i, strlen( '</onlyinclude>' ) ) == '</onlyinclude>'
 353                                 ) {
 354                                         $findOnlyinclude = true;
 355                                         continue;
 356                                 }
 357
 358                                 // Determine element name
 359                                 if ( !preg_match( $elementsRegex, $text, $matches, 0, $i + 1 ) ) {
 360                                         // Element name missing or not listed
 361                                         $accum .= '&lt;';
 362                                         ++$i;
 363                                         continue;
 364                                 }
 365                                 // Handle comments
 366                                 if ( isset( $matches[2] ) && $matches[2] == '!--' ) {
 367                                         // To avoid leaving blank lines, when a sequence of
 368                                         // space-separated comments is both preceded and followed by
 369                                         // a newline (ignoring spaces), then
 370                                         // trim leading and trailing spaces and the trailing newline.
 371
 372                                         // Find the end
 373                                         $endPos = strpos( $text, '-->', $i + 4 );
 374                                         if ( $endPos === false ) {
 375                                                 // Unclosed comment in input, runs to end
 376                                                 $inner = substr( $text, $i );
 377                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 378                                                 $i = $lengthText;
 379                                         } else {
 380                                                 // Search backwards for leading whitespace
 381                                                 $wsStart = $i ? ( $i - strspn( $revText, " \t", $lengthText - $i ) ) : 0;
 382
 383                                                 // Search forwards for trailing whitespace
 384                                                 // $wsEnd will be the position of the last space (or the '>' if there's none)
 385                                                 $wsEnd = $endPos + 2 + strspn( $text, " \t", $endPos + 3 );
 386
 387                                                 // Keep looking forward as long as we're finding more
 388                                                 // comments.
 389                                                 $comments = [ [ $wsStart, $wsEnd ] ];
 390                                                 while ( substr( $text, $wsEnd + 1, 4 ) == '<!--' ) {
 391                                                         $c = strpos( $text, '-->', $wsEnd + 4 );
 392                                                         if ( $c === false ) {
 393                                                                 break;
 394                                                         }
 395                                                         $c = $c + 2 + strspn( $text, " \t", $c + 3 );
 396                                                         $comments[] = [ $wsEnd + 1, $c ];
 397                                                         $wsEnd = $c;
 398                                                 }
 399
 400                                                 // Eat the line if possible
 401                                                 // TODO: This could theoretically be done if $wsStart == 0, i.e. for comments at
 402                                                 // the overall start. That's not how Sanitizer::removeHTMLcomments() did it, but
 403                                                 // it's a possible beneficial b/c break.
 404                                                 if ( $wsStart > 0 && substr( $text, $wsStart - 1, 1 ) == "\n"
 405                                                         && substr( $text, $wsEnd + 1, 1 ) == "\n"
 406                                                 ) {
 407                                                         // Remove leading whitespace from the end of the accumulator
 408                                                         // Sanity check first though
 409                                                         $wsLength = $i - $wsStart;
 410                                                         if ( $wsLength > 0
 411                                                                 && strspn( $accum, " \t", -$wsLength ) === $wsLength
 412                                                         ) {
 413                                                                 $accum = substr( $accum, 0, -$wsLength );
 414                                                         }
 415
 416                                                         // Dump all but the last comment to the accumulator
 417                                                         foreach ( $comments as $j => $com ) {
 418                                                                 $startPos = $com[0];
 419                                                                 $endPos = $com[1] + 1;
 420                                                                 if ( $j == ( count( $comments ) - 1 ) ) {
 421                                                                         break;
 422                                                                 }
 423                                                                 $inner = substr( $text, $startPos, $endPos - $startPos );
 424                                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 425                                                         }
 426
 427                                                         // Do a line-start run next time to look for headings after the comment
 428                                                         $fakeLineStart = true;
 429                                                 } else {
 430                                                         // No line to eat, just take the comment itself
 431                                                         $startPos = $i;
 432                                                         $endPos += 2;
 433                                                 }
 434
 435                                                 if ( $stack->top ) {
 436                                                         $part = $stack->top->getCurrentPart();
 437                                                         if ( !( isset( $part->commentEnd ) && $part->commentEnd == $wsStart - 1 ) ) {
 438                                                                 $part->visualEnd = $wsStart;
 439                                                         }
 440                                                         // Else comments abutting, no change in visual end
 441                                                         $part->commentEnd = $endPos;
 442                                                 }
 443                                                 $i = $endPos + 1;
 444                                                 $inner = substr( $text, $startPos, $endPos - $startPos + 1 );
 445                                                 $accum .= '<comment>' . htmlspecialchars( $inner ) . '</comment>';
 446                                         }
 447                                         continue;
 448                                 }
 449                                 $name = $matches[1];
 450                                 $lowerName = strtolower( $name );
 451                                 $attrStart = $i + strlen( $name ) + 1;
 452
 453                                 // Find end of tag
 454                                 $tagEndPos = $noMoreGT ? false : strpos( $text, '>', $attrStart );
 455                                 if ( $tagEndPos === false ) {
 456                                         // Infinite backtrack
 457                                         // Disable tag search to prevent worst-case O(N^2) performance
 458                                         $noMoreGT = true;
 459                                         $accum .= '&lt;';
 460                                         ++$i;
 461                                         continue;
 462                                 }
 463
 464                                 // Handle ignored tags
 465                                 if ( in_array( $lowerName, $ignoredTags ) ) {
 466                                         $accum .= '<ignore>'
 467                                                 . htmlspecialchars( substr( $text, $i, $tagEndPos - $i + 1 ) )
 468                                                 . '</ignore>';
 469                                         $i = $tagEndPos + 1;
 470                                         continue;
 471                                 }
 472
 473                                 $tagStartPos = $i;
 474                                 if ( $text[$tagEndPos - 1] == '/' ) {
 475                                         $attrEnd = $tagEndPos - 1;
 476                                         $inner = null;
 477                                         $i = $tagEndPos + 1;
 478                                         $close = '';
 479                                 } else {
 480                                         $attrEnd = $tagEndPos;
 481                                         // Find closing tag
 482                                         if (
 483                                                 !isset( $noMoreClosingTag[$name] ) &&
 484                                                 preg_match( "/<\/" . preg_quote( $name, '/' ) . "\s*>/i",
 485                                                         $text, $matches, PREG_OFFSET_CAPTURE, $tagEndPos + 1 )
 486                                         ) {
 487                                                 $inner = substr( $text, $tagEndPos + 1, $matches[0][1] - $tagEndPos - 1 );
 488                                                 $i = $matches[0][1] + strlen( $matches[0][0] );
 489                                                 $close = '<close>' . htmlspecialchars( $matches[0][0] ) . '</close>';
 490                                         } else {
 491                                                 // No end tag
 492                                                 if ( in_array( $name, $xmlishAllowMissingEndTag ) ) {
 493                                                         // Let it run out to the end of the text.
 494                                                         $inner = substr( $text, $tagEndPos + 1 );
 495                                                         $i = $lengthText;
 496                                                         $close = '';
 497                                                 } else {
 498                                                         // Don't match the tag, treat opening tag as literal and resume parsing.
 499                                                         $i = $tagEndPos + 1;
 500                                                         $accum .= htmlspecialchars( substr( $text, $tagStartPos, $tagEndPos + 1 - $tagStartPos ) );
 501                                                         // Cache results, otherwise we have O(N^2) performance for input like <foo><foo><foo>...
 502                                                         $noMoreClosingTag[$name] = true;
 503                                                         continue;
 504                                                 }
 505                                         }
 506                                 }
 507                                 // <includeonly> and <noinclude> just become <ignore> tags
 508                                 if ( in_array( $lowerName, $ignoredElements ) ) {
 509                                         $accum .= '<ignore>' . htmlspecialchars( substr( $text, $tagStartPos, $i - $tagStartPos ) )
 510                                                 . '</ignore>';
 511                                         continue;
 512                                 }
 513
 514                                 $accum .= '<ext>';
 515                                 if ( $attrEnd <= $attrStart ) {
 516                                         $attr = '';
 517                                 } else {
 518                                         $attr = substr( $text, $attrStart, $attrEnd - $attrStart );
 519                                 }
 520                                 $accum .= '<name>' . htmlspecialchars( $name ) . '</name>' .
 521                                         // Note that the attr element contains the whitespace between name and attribute,
 522                                         // this is necessary for precise reconstruction during pre-save transform.
 523                                         '<attr>' . htmlspecialchars( $attr ) . '</attr>';
 524                                 if ( $inner !== null ) {
 525                                         $accum .= '<inner>' . htmlspecialchars( $inner ) . '</inner>';
 526                                 }
 527                                 $accum .= $close . '</ext>';
 528                         } elseif ( $found == 'line-start' ) {
 529                                 // Is this the start of a heading?
 530                                 // Line break belongs before the heading element in any case
 531                                 if ( $fakeLineStart ) {
 532                                         $fakeLineStart = false;
 533                                 } else {
 534                                         $accum .= $curChar;
 535                                         $i++;
 536                                 }
 537
 538                                 $count = strspn( $text, '=', $i, 6 );
 539                                 if ( $count == 1 && $findEquals ) {
 540                                         // DWIM: This looks kind of like a name/value separator.
 541                                         // Let's let the equals handler have it and break the
 542                                         // potential heading. This is heuristic, but AFAICT the
 543                                         // methods for completely correct disambiguation are very
 544                                         // complex.
 545                                 } elseif ( $count > 0 ) {
 546                                         $piece = [
 547                                                 'open' => "\n",
 548                                                 'close' => "\n",
 549                                                 'parts' => [ new PPDPart( str_repeat( '=', $count ) ) ],
 550                                                 'startPos' => $i,
 551                                                 'count' => $count ];
 552                                         $stack->push( $piece );
 553                                         $accum =& $stack->getAccum();
 554                                         $stackFlags = $stack->getFlags();
 555                                         if ( isset( $stackFlags['findEquals'] ) ) {
 556                                                 $findEquals = $stackFlags['findEquals'];
 557                                         }
 558                                         if ( isset( $stackFlags['findPipe'] ) ) {
 559                                                 $findPipe = $stackFlags['findPipe'];
 560                                         }
 561                                         if ( isset( $stackFlags['inHeading'] ) ) {
 562                                                 $inHeading = $stackFlags['inHeading'];
 563                                         }
 564                                         $i += $count;
 565                                 }
 566                         } elseif ( $found == 'line-end' ) {
 567                                 $piece = $stack->top;
 568                                 // A heading must be open, otherwise \n wouldn't have been in the search list
 569                                 // FIXME: Don't use assert()
 570                                 // phpcs:ignore MediaWiki.Usage.ForbiddenFunctions.assert
 571                                 assert( $piece->open === "\n" );
 572                                 $part = $piece->getCurrentPart();
 573                                 // Search back through the input to see if it has a proper close.
 574                                 // Do this using the reversed string since the other solutions
 575                                 // (end anchor, etc.) are inefficient.
 576                                 $wsLength = strspn( $revText, " \t", $lengthText - $i );
 577                                 $searchStart = $i - $wsLength;
 578                                 if ( isset( $part->commentEnd ) && $searchStart - 1 == $part->commentEnd ) {
 579                                         // Comment found at line end
 580                                         // Search for equals signs before the comment
 581                                         $searchStart = $part->visualEnd;
 582                                         $searchStart -= strspn( $revText, " \t", $lengthText - $searchStart );
 583                                 }
 584                                 $count = $piece->count;
 585                                 $equalsLength = strspn( $revText, '=', $lengthText - $searchStart );
 586                                 if ( $equalsLength > 0 ) {
 587                                         if ( $searchStart - $equalsLength == $piece->startPos ) {
 588                                                 // This is just a single string of equals signs on its own line
 589                                                 // Replicate the doHeadings behavior /={count}(.+)={count}/
 590                                                 // First find out how many equals signs there really are (don't stop at 6)
 591                                                 $count = $equalsLength;
 592                                                 if ( $count < 3 ) {
 593                                                         $count = 0;
 594                                                 } else {
 595                                                         $count = min( 6, intval( ( $count - 1 ) / 2 ) );
 596                                                 }
 597                                         } else {
 598                                                 $count = min( $equalsLength, $count );
 599                                         }
 600                                         if ( $count > 0 ) {
 601                                                 // Normal match, output <h>
 602                                                 $element = "<h level=\"$count\" i=\"$headingIndex\">$accum</h>";
 603                                                 $headingIndex++;
 604                                         } else {
 605                                                 // Single equals sign on its own line, count=0
 606                                                 $element = $accum;
 607                                         }
 608                                 } else {
 609                                         // No match, no <h>, just pass down the inner text
 610                                         $element = $accum;
 611                                 }
 612                                 // Unwind the stack
 613                                 $stack->pop();
 614                                 $accum =& $stack->getAccum();
 615                                 $stackFlags = $stack->getFlags();
 616                                 if ( isset( $stackFlags['findEquals'] ) ) {
 617                                         $findEquals = $stackFlags['findEquals'];
 618                                 }
 619                                 if ( isset( $stackFlags['findPipe'] ) ) {
 620                                         $findPipe = $stackFlags['findPipe'];
 621                                 }
 622                                 if ( isset( $stackFlags['inHeading'] ) ) {
 623                                         $inHeading = $stackFlags['inHeading'];
 624                                 }
 625
 626                                 // Append the result to the enclosing accumulator
 627                                 $accum .= $element;
 628                                 // Note that we do NOT increment the input pointer.
 629                                 // This is because the closing linebreak could be the opening linebreak of
 630                                 // another heading. Infinite loops are avoided because the next iteration MUST
 631                                 // hit the heading open case above, which unconditionally increments the
 632                                 // input pointer.
 633                         } elseif ( $found == 'open' ) {
 634                                 # count opening brace characters
 635                                 $curLen = strlen( $curChar );
 636                                 $count = ( $curLen > 1 ) ?
 637                                         # allow the final character to repeat
 638                                         strspn( $text, $curChar[$curLen - 1], $i + 1 ) + 1 :
 639                                         strspn( $text, $curChar, $i );
 640
 641                                 $savedPrefix = '';
 642                                 $lineStart = ( $i > 0 && $text[$i - 1] == "\n" );
 643
 644                                 if ( $curChar === "-{" && $count > $curLen ) {
 645                                         // -{ => {{ transition because rightmost wins
 646                                         $savedPrefix = '-';
 647                                         $i++;
 648                                         $curChar = '{';
 649                                         $count--;
 650                                         $rule = $this->rules[$curChar];
 651                                 }
 652
 653                                 # we need to add to stack only if opening brace count is enough for one of the rules
 654                                 if ( $count >= $rule['min'] ) {
 655                                         # Add it to the stack
 656                                         $piece = [
 657                                                 'open' => $curChar,
 658                                                 'close' => $rule['end'],
 659                                                 'savedPrefix' => $savedPrefix,
 660                                                 'count' => $count,
 661                                                 'lineStart' => $lineStart,
 662                                         ];
 663
 664                                         $stack->push( $piece );
 665                                         $accum =& $stack->getAccum();
 666                                         $stackFlags = $stack->getFlags();
 667                                         if ( isset( $stackFlags['findEquals'] ) ) {
 668                                                 $findEquals = $stackFlags['findEquals'];
 669                                         }
 670                                         if ( isset( $stackFlags['findPipe'] ) ) {
 671                                                 $findPipe = $stackFlags['findPipe'];
 672                                         }
 673                                         if ( isset( $stackFlags['inHeading'] ) ) {
 674                                                 $inHeading = $stackFlags['inHeading'];
 675                                         }
 676                                 } else {
 677                                         # Add literal brace(s)
 678                                         $accum .= htmlspecialchars( $savedPrefix . str_repeat( $curChar, $count ) );
 679                                 }
 680                                 $i += $count;
 681                         } elseif ( $found == 'close' ) {
 682                                 $piece = $stack->top;
 683                                 # lets check if there are enough characters for closing brace
 684                                 $maxCount = $piece->count;
 685                                 if ( $piece->close === '}-' && $curChar === '}' ) {
 686                                         $maxCount--; # don't try to match closing '-' as a '}'
 687                                 }
 688                                 $curLen = strlen( $curChar );
 689                                 $count = ( $curLen > 1 ) ? $curLen :
 690                                         strspn( $text, $curChar, $i, $maxCount );
 691
 692                                 # check for maximum matching characters (if there are 5 closing
 693                                 # characters, we will probably need only 3 - depending on the rules)
 694                                 $rule = $this->rules[$piece->open];
 695                                 if ( $count > $rule['max'] ) {
 696                                         # The specified maximum exists in the callback array, unless the caller
 697                                         # has made an error
 698                                         $matchingCount = $rule['max'];
 699                                 } else {
 700                                         # Count is less than the maximum
 701                                         # Skip any gaps in the callback array to find the true largest match
 702                                         # Need to use array_key_exists not isset because the callback can be null
 703                                         $matchingCount = $count;
 704                                         while ( $matchingCount > 0 && !array_key_exists( $matchingCount, $rule['names'] ) ) {
 705                                                 --$matchingCount;
 706                                         }
 707                                 }
 708
 709                                 if ( $matchingCount <= 0 ) {
 710                                         # No matching element found in callback array
 711                                         # Output a literal closing brace and continue
 712                                         $endText = substr( $text, $i, $count );
 713                                         $accum .= htmlspecialchars( $endText );
 714                                         $i += $count;
 715                                         continue;
 716                                 }
 717                                 $name = $rule['names'][$matchingCount];
 718                                 if ( $name === null ) {
 719                                         // No element, just literal text
 720                                         $endText = substr( $text, $i, $matchingCount );
 721                                         $element = $piece->breakSyntax( $matchingCount ) . $endText;
 722                                 } else {
 723                                         # Create XML element
 724                                         # Note: $parts is already XML, does not need to be encoded further
 725                                         $parts = $piece->parts;
 726                                         $title = $parts[0]->out;
 727                                         unset( $parts[0] );
 728
 729                                         # The invocation is at the start of the line if lineStart is set in
 730                                         # the stack, and all opening brackets are used up.
 731                                         if ( $maxCount == $matchingCount &&
 732                                                         !empty( $piece->lineStart ) &&
 733                                                         strlen( $piece->savedPrefix ) == 0 ) {
 734                                                 $attr = ' lineStart="1"';
 735                                         } else {
 736                                                 $attr = '';
 737                                         }
 738
 739                                         $element = "<$name$attr>";
 740                                         $element .= "<title>$title</title>";
 741                                         $argIndex = 1;
 742                                         foreach ( $parts as $part ) {
 743                                                 if ( isset( $part->eqpos ) ) {
 744                                                         $argName = substr( $part->out, 0, $part->eqpos );
 745                                                         $argValue = substr( $part->out, $part->eqpos + 1 );
 746                                                         $element .= "<part><name>$argName</name>=<value>$argValue</value></part>";
 747                                                 } else {
 748                                                         $element .= "<part><name index=\"$argIndex\" /><value>{$part->out}</value></part>";
 749                                                         $argIndex++;
 750                                                 }
 751                                         }
 752                                         $element .= "</$name>";
 753                                 }
 754
 755                                 # Advance input pointer
 756                                 $i += $matchingCount;
 757
 758                                 # Unwind the stack
 759                                 $stack->pop();
 760                                 $accum =& $stack->getAccum();
 761
 762                                 # Re-add the old stack element if it still has unmatched opening characters remaining
 763                                 if ( $matchingCount < $piece->count ) {
 764                                         $piece->parts = [ new PPDPart ];
 765                                         $piece->count -= $matchingCount;
 766                                         # do we still qualify for any callback with remaining count?
 767                                         $min = $this->rules[$piece->open]['min'];
 768                                         if ( $piece->count >= $min ) {
 769                                                 $stack->push( $piece );
 770                                                 $accum =& $stack->getAccum();
 771                                         } elseif ( $piece->count == 1 && $piece->open === '{' && $piece->savedPrefix === '-' ) {
 772                                                 $piece->savedPrefix = '';
 773                                                 $piece->open = '-{';
 774                                                 $piece->count = 2;
 775                                                 $piece->close = $this->rules[$piece->open]['end'];
 776                                                 $stack->push( $piece );
 777                                                 $accum =& $stack->getAccum();
 778                                         } else {
 779                                                 $s = substr( $piece->open, 0, -1 );
 780                                                 $s .= str_repeat(
 781                                                         substr( $piece->open, -1 ),
 782                                                         $piece->count - strlen( $s )
 783                                                 );
 784                                                 $accum .= $piece->savedPrefix . $s;
 785                                         }
 786                                 } elseif ( $piece->savedPrefix !== '' ) {
 787                                         $accum .= $piece->savedPrefix;
 788                                 }
 789
 790                                 $stackFlags = $stack->getFlags();
 791                                 if ( isset( $stackFlags['findEquals'] ) ) {
 792                                         $findEquals = $stackFlags['findEquals'];
 793                                 }
 794                                 if ( isset( $stackFlags['findPipe'] ) ) {
 795                                         $findPipe = $stackFlags['findPipe'];
 796                                 }
 797                                 if ( isset( $stackFlags['inHeading'] ) ) {
 798                                         $inHeading = $stackFlags['inHeading'];
 799                                 }
 800
 801                                 # Add XML element to the enclosing accumulator
 802                                 $accum .= $element;
 803                         } elseif ( $found == 'pipe' ) {
 804                                 $findEquals = true; // shortcut for getFlags()
 805                                 $stack->addPart();
 806                                 $accum =& $stack->getAccum();
 807                                 ++$i;
 808                         } elseif ( $found == 'equals' ) {
 809                                 $findEquals = false; // shortcut for getFlags()
 810                                 $stack->getCurrentPart()->eqpos = strlen( $accum );
 811                                 $accum .= '=';
 812                                 ++$i;
 813                         }
 814                 }
 815
 816                 # Output any remaining unclosed brackets
 817                 foreach ( $stack->stack as $piece ) {
 818                         $stack->rootAccum .= $piece->breakSyntax();
 819                 }
 820                 $stack->rootAccum .= '</root>';
 821                 $xml = $stack->rootAccum;
 822
 823                 return $xml;
 824         }
 825 }
 826
 827 /**
 828  * Stack class to help Preprocessor::preprocessToObj()
 829  * @ingroup Parser
 830  */
 831 class PPDStack {
 832         public $stack, $rootAccum;
 833
 834         /**
 835          * @var PPDStack
 836          */
 837         public $top;
 838         public $out;
 839         public $elementClass = PPDStackElement::class;
 840
 841         public static $false = false;
 842
 843         public function __construct() {
 844                 $this->stack = [];
 845                 $this->top = false;
 846                 $this->rootAccum = '';
 847                 $this->accum =& $this->rootAccum;
 848         }
 849
 850         /**
 851          * @return int
 852          */
 853         public function count() {
 854                 return count( $this->stack );
 855         }
 856
 857         public function &getAccum() {
 858                 return $this->accum;
 859         }
 860
 861         public function getCurrentPart() {
 862                 if ( $this->top === false ) {
 863                         return false;
 864                 } else {
 865                         return $this->top->getCurrentPart();
 866                 }
 867         }
 868
 869         public function push( $data ) {
 870                 if ( $data instanceof $this->elementClass ) {
 871                         $this->stack[] = $data;
 872                 } else {
 873                         $class = $this->elementClass;
 874                         $this->stack[] = new $class( $data );
 875                 }
 876                 $this->top = $this->stack[count( $this->stack ) - 1];
 877                 $this->accum =& $this->top->getAccum();
 878         }
 879
 880         public function pop() {
 881                 if ( !count( $this->stack ) ) {
 882                         throw new MWException( __METHOD__ . ': no elements remaining' );
 883                 }
 884                 $temp = array_pop( $this->stack );
 885
 886                 if ( count( $this->stack ) ) {
 887                         $this->top = $this->stack[count( $this->stack ) - 1];
 888                         $this->accum =& $this->top->getAccum();
 889                 } else {
 890                         $this->top = self::$false;
 891                         $this->accum =& $this->rootAccum;
 892                 }
 893                 return $temp;
 894         }
 895
 896         public function addPart( $s = '' ) {
 897                 $this->top->addPart( $s );
 898                 $this->accum =& $this->top->getAccum();
 899         }
 900
 901         /**
 902          * @return array
 903          */
 904         public function getFlags() {
 905                 if ( !count( $this->stack ) ) {
 906                         return [
 907                                 'findEquals' => false,
 908                                 'findPipe' => false,
 909                                 'inHeading' => false,
 910                         ];
 911                 } else {
 912                         return $this->top->getFlags();
 913                 }
 914         }
 915 }
 916
 917 /**
 918  * @ingroup Parser
 919  */
 920 class PPDStackElement {
 921         /**
 922          * @var string Opening character (\n for heading)
 923          */
 924         public $open;
 925
 926         /**
 927          * @var string Matching closing character
 928          */
 929         public $close;
 930
 931         /**
 932          * @var string Saved prefix that may affect later processing,
 933          *  e.g. to differentiate `-{{{{` and `{{{{` after later seeing `}}}`.
 934          */
 935         public $savedPrefix = '';
 936
 937         /**
 938          * @var int Number of opening characters found (number of "=" for heading)
 939          */
 940         public $count;
 941
 942         /**
 943          * @var PPDPart[] Array of PPDPart objects describing pipe-separated parts.
 944          */
 945         public $parts;
 946
 947         /**
 948          * @var bool True if the open char appeared at the start of the input line.
 949          *  Not set for headings.
 950          */
 951         public $lineStart;
 952
 953         public $partClass = PPDPart::class;
 954
 955         public function __construct( $data = [] ) {
 956                 $class = $this->partClass;
 957                 $this->parts = [ new $class ];
 958
 959                 foreach ( $data as $name => $value ) {
 960                         $this->$name = $value;
 961                 }
 962         }
 963
 964         public function &getAccum() {
 965                 return $this->parts[count( $this->parts ) - 1]->out;
 966         }
 967
 968         public function addPart( $s = '' ) {
 969                 $class = $this->partClass;
 970                 $this->parts[] = new $class( $s );
 971         }
 972
 973         public function getCurrentPart() {
 974                 return $this->parts[count( $this->parts ) - 1];
 975         }
 976
 977         /**
 978          * @return array
 979          */
 980         public function getFlags() {
 981                 $partCount = count( $this->parts );
 982                 $findPipe = $this->open != "\n" && $this->open != '[';
 983                 return [
 984                         'findPipe' => $findPipe,
 985                         'findEquals' => $findPipe && $partCount > 1 && !isset( $this->parts[$partCount - 1]->eqpos ),
 986                         'inHeading' => $this->open == "\n",
 987                 ];
 988         }
 989
 990         /**
 991          * Get the output string that would result if the close is not found.
 992          *
 993          * @param bool|int $openingCount
 994          * @return string
 995          */
 996         public function breakSyntax( $openingCount = false ) {
 997                 if ( $this->open == "\n" ) {
 998                         $s = $this->savedPrefix . $this->parts[0]->out;
 999                 } else {
1000                         if ( $openingCount === false ) {
1001                                 $openingCount = $this->count;
1002                         }
1003                         $s = substr( $this->open, 0, -1 );
1004                         $s .= str_repeat(
1005                                 substr( $this->open, -1 ),
1006                                 $openingCount - strlen( $s )
1007                         );
1008                         $s = $this->savedPrefix . $s;
1009                         $first = true;
1010                         foreach ( $this->parts as $part ) {
1011                                 if ( $first ) {
1012                                         $first = false;
1013                                 } else {
1014                                         $s .= '|';
1015                                 }
1016                                 $s .= $part->out;
1017                         }
1018                 }
1019                 return $s;
1020         }
1021 }
1022
1023 /**
1024  * @ingroup Parser
1025  */
1026 class PPDPart {
1027         /**
1028          * @var string Output accumulator string
1029          */
1030         public $out;
1031
1032         // Optional member variables:
1033         //   eqpos        Position of equals sign in output accumulator
1034         //   commentEnd   Past-the-end input pointer for the last comment encountered
1035         //   visualEnd    Past-the-end input pointer for the end of the accumulator minus comments
1036
1037         public function __construct( $out = '' ) {
1038                 $this->out = $out;
1039         }
1040 }
1041
1042 /**
1043  * An expansion frame, used as a context to expand the result of preprocessToObj()
1044  * @ingroup Parser
1045  */
1046 // phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
1047 class PPFrame_DOM implements PPFrame {
1048
1049         /**
1050          * @var Preprocessor
1051          */
1052         public $preprocessor;
1053
1054         /**
1055          * @var Parser
1056          */
1057         public $parser;
1058
1059         /**
1060          * @var Title
1061          */
1062         public $title;
1063         public $titleCache;
1064
1065         /**
1066          * Hashtable listing templates which are disallowed for expansion in this frame,
1067          * having been encountered previously in parent frames.
1068          */
1069         public $loopCheckHash;
1070
1071         /**
1072          * Recursion depth of this frame, top = 0
1073          * Note that this is NOT the same as expansion depth in expand()
1074          */
1075         public $depth;
1076
1077         private $volatile = false;
1078         private $ttl = null;
1079
1080         /**
1081          * @var array
1082          */
1083         protected $childExpansionCache;
1084
1085         /**
1086          * Construct a new preprocessor frame.
1087          * @param Preprocessor $preprocessor The parent preprocessor
1088          */
1089         public function __construct( $preprocessor ) {
1090                 $this->preprocessor = $preprocessor;
1091                 $this->parser = $preprocessor->parser;
1092                 $this->title = $this->parser->mTitle;
1093                 $this->titleCache = [ $this->title ? $this->title->getPrefixedDBkey() : false ];
1094                 $this->loopCheckHash = [];
1095                 $this->depth = 0;
1096                 $this->childExpansionCache = [];
1097         }
1098
1099         /**
1100          * Create a new child frame
1101          * $args is optionally a multi-root PPNode or array containing the template arguments
1102          *
1103          * @param bool|array $args
1104          * @param Title|bool $title
1105          * @param int $indexOffset
1106          * @return PPTemplateFrame_DOM
1107          */
1108         public function newChild( $args = false, $title = false, $indexOffset = 0 ) {
1109                 $namedArgs = [];
1110                 $numberedArgs = [];
1111                 if ( $title === false ) {
1112                         $title = $this->title;
1113                 }
1114                 if ( $args !== false ) {
1115                         $xpath = false;
1116                         if ( $args instanceof PPNode ) {
1117                                 $args = $args->node;
1118                         }
1119                         foreach ( $args as $arg ) {
1120                                 if ( $arg instanceof PPNode ) {
1121                                         $arg = $arg->node;
1122                                 }
1123                                 if ( !$xpath || $xpath->document !== $arg->ownerDocument ) {
1124                                         $xpath = new DOMXPath( $arg->ownerDocument );
1125                                 }
1126
1127                                 $nameNodes = $xpath->query( 'name', $arg );
1128                                 $value = $xpath->query( 'value', $arg );
1129                                 if ( $nameNodes->item( 0 )->hasAttributes() ) {
1130                                         // Numbered parameter
1131                                         $index = $nameNodes->item( 0 )->attributes->getNamedItem( 'index' )->textContent;
1132                                         $index = $index - $indexOffset;
1133                                         if ( isset( $namedArgs[$index] ) || isset( $numberedArgs[$index] ) ) {
1134                                                 $this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
1135                                                         wfEscapeWikiText( $this->title ),
1136                                                         wfEscapeWikiText( $title ),
1137                                                         wfEscapeWikiText( $index ) )->text() );
1138                                                 $this->parser->addTrackingCategory( 'duplicate-args-category' );
1139                                         }
1140                                         $numberedArgs[$index] = $value->item( 0 );
1141                                         unset( $namedArgs[$index] );
1142                                 } else {
1143                                         // Named parameter
1144                                         $name = trim( $this->expand( $nameNodes->item( 0 ), PPFrame::STRIP_COMMENTS ) );
1145                                         if ( isset( $namedArgs[$name] ) || isset( $numberedArgs[$name] ) ) {
1146                                                 $this->parser->getOutput()->addWarning( wfMessage( 'duplicate-args-warning',
1147                                                         wfEscapeWikiText( $this->title ),
1148                                                         wfEscapeWikiText( $title ),
1149                                                         wfEscapeWikiText( $name ) )->text() );
1150                                                 $this->parser->addTrackingCategory( 'duplicate-args-category' );
1151                                         }
1152                                         $namedArgs[$name] = $value->item( 0 );
1153                                         unset( $numberedArgs[$name] );
1154                                 }
1155                         }
1156                 }
1157                 return new PPTemplateFrame_DOM( $this->preprocessor, $this, $numberedArgs, $namedArgs, $title );
1158         }
1159
1160         /**
1161          * @throws MWException
1162          * @param string|int $key
1163          * @param string|PPNode_DOM|DOMDocument $root
1164          * @param int $flags
1165          * @return string
1166          */
1167         public function cachedExpand( $key, $root, $flags = 0 ) {
1168                 // we don't have a parent, so we don't have a cache
1169                 return $this->expand( $root, $flags );
1170         }
1171
1172         /**
1173          * @throws MWException
1174          * @param string|PPNode_DOM|DOMDocument $root
1175          * @param int $flags
1176          * @return string
1177          */
1178         public function expand( $root, $flags = 0 ) {
1179                 static $expansionDepth = 0;
1180                 if ( is_string( $root ) ) {
1181                         return $root;
1182                 }
1183
1184                 if ( ++$this->parser->mPPNodeCount > $this->parser->mOptions->getMaxPPNodeCount() ) {
1185                         $this->parser->limitationWarn( 'node-count-exceeded',
1186                                 $this->parser->mPPNodeCount,
1187                                 $this->parser->mOptions->getMaxPPNodeCount()
1188                         );
1189                         return '<span class="error">Node-count limit exceeded</span>';
1190                 }
1191
1192                 if ( $expansionDepth > $this->parser->mOptions->getMaxPPExpandDepth() ) {
1193                         $this->parser->limitationWarn( 'expansion-depth-exceeded',
1194                                 $expansionDepth,
1195                                 $this->parser->mOptions->getMaxPPExpandDepth()
1196                         );
1197                         return '<span class="error">Expansion depth limit exceeded</span>';
1198                 }
1199                 ++$expansionDepth;
1200                 if ( $expansionDepth > $this->parser->mHighestExpansionDepth ) {
1201                         $this->parser->mHighestExpansionDepth = $expansionDepth;
1202                 }
1203
1204                 if ( $root instanceof PPNode_DOM ) {
1205                         $root = $root->node;
1206                 }
1207                 if ( $root instanceof DOMDocument ) {
1208                         $root = $root->documentElement;
1209                 }
1210
1211                 $outStack = [ '', '' ];
1212                 $iteratorStack = [ false, $root ];
1213                 $indexStack = [ 0, 0 ];
1214
1215                 while ( count( $iteratorStack ) > 1 ) {
1216                         $level = count( $outStack ) - 1;
1217                         $iteratorNode =& $iteratorStack[$level];
1218                         $out =& $outStack[$level];
1219                         $index =& $indexStack[$level];
1220
1221                         if ( $iteratorNode instanceof PPNode_DOM ) {
1222                                 $iteratorNode = $iteratorNode->node;
1223                         }
1224
1225                         if ( is_array( $iteratorNode ) ) {
1226                                 if ( $index >= count( $iteratorNode ) ) {
1227                                         // All done with this iterator
1228                                         $iteratorStack[$level] = false;
1229                                         $contextNode = false;
1230                                 } else {
1231                                         $contextNode = $iteratorNode[$index];
1232                                         $index++;
1233                                 }
1234                         } elseif ( $iteratorNode instanceof DOMNodeList ) {
1235                                 if ( $index >= $iteratorNode->length ) {
1236                                         // All done with this iterator
1237                                         $iteratorStack[$level] = false;
1238                                         $contextNode = false;
1239                                 } else {
1240                                         $contextNode = $iteratorNode->item( $index );
1241                                         $index++;
1242                                 }
1243                         } else {
1244                                 // Copy to $contextNode and then delete from iterator stack,
1245                                 // because this is not an iterator but we do have to execute it once
1246                                 $contextNode = $iteratorStack[$level];
1247                                 $iteratorStack[$level] = false;
1248                         }
1249
1250                         if ( $contextNode instanceof PPNode_DOM ) {
1251                                 $contextNode = $contextNode->node;
1252                         }
1253
1254                         $newIterator = false;
1255
1256                         if ( $contextNode === false ) {
1257                                 // nothing to do
1258                         } elseif ( is_string( $contextNode ) ) {
1259                                 $out .= $contextNode;
1260                         } elseif ( is_array( $contextNode ) || $contextNode instanceof DOMNodeList ) {
1261                                 $newIterator = $contextNode;
1262                         } elseif ( $contextNode instanceof DOMNode ) {
1263                                 if ( $contextNode->nodeType == XML_TEXT_NODE ) {
1264                                         $out .= $contextNode->nodeValue;
1265                                 } elseif ( $contextNode->nodeName == 'template' ) {
1266                                         # Double-brace expansion
1267                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1268                                         $titles = $xpath->query( 'title', $contextNode );
1269                                         $title = $titles->item( 0 );
1270                                         $parts = $xpath->query( 'part', $contextNode );
1271                                         if ( $flags & PPFrame::NO_TEMPLATES ) {
1272                                                 $newIterator = $this->virtualBracketedImplode( '{{', '|', '}}', $title, $parts );
1273                                         } else {
1274                                                 $lineStart = $contextNode->getAttribute( 'lineStart' );
1275                                                 $params = [
1276                                                         'title' => new PPNode_DOM( $title ),
1277                                                         'parts' => new PPNode_DOM( $parts ),
1278                                                         'lineStart' => $lineStart ];
1279                                                 $ret = $this->parser->braceSubstitution( $params, $this );
1280                                                 if ( isset( $ret['object'] ) ) {
1281                                                         $newIterator = $ret['object'];
1282                                                 } else {
1283                                                         $out .= $ret['text'];
1284                                                 }
1285                                         }
1286                                 } elseif ( $contextNode->nodeName == 'tplarg' ) {
1287                                         # Triple-brace expansion
1288                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1289                                         $titles = $xpath->query( 'title', $contextNode );
1290                                         $title = $titles->item( 0 );
1291                                         $parts = $xpath->query( 'part', $contextNode );
1292                                         if ( $flags & PPFrame::NO_ARGS ) {
1293                                                 $newIterator = $this->virtualBracketedImplode( '{{{', '|', '}}}', $title, $parts );
1294                                         } else {
1295                                                 $params = [
1296                                                         'title' => new PPNode_DOM( $title ),
1297                                                         'parts' => new PPNode_DOM( $parts ) ];
1298                                                 $ret = $this->parser->argSubstitution( $params, $this );
1299                                                 if ( isset( $ret['object'] ) ) {
1300                                                         $newIterator = $ret['object'];
1301                                                 } else {
1302                                                         $out .= $ret['text'];
1303                                                 }
1304                                         }
1305                                 } elseif ( $contextNode->nodeName == 'comment' ) {
1306                                         # HTML-style comment
1307                                         # Remove it in HTML, pre+remove and STRIP_COMMENTS modes
1308                                         # Not in RECOVER_COMMENTS mode (msgnw) though.
1309                                         if ( ( $this->parser->ot['html']
1310                                                 || ( $this->parser->ot['pre'] && $this->parser->mOptions->getRemoveComments() )
1311                                                 || ( $flags & PPFrame::STRIP_COMMENTS )
1312                                                 ) && !( $flags & PPFrame::RECOVER_COMMENTS )
1313                                         ) {
1314                                                 $out .= '';
1315                                         } elseif ( $this->parser->ot['wiki'] && !( $flags & PPFrame::RECOVER_COMMENTS ) ) {
1316                                                 # Add a strip marker in PST mode so that pstPass2() can
1317                                                 # run some old-fashioned regexes on the result.
1318                                                 # Not in RECOVER_COMMENTS mode (extractSections) though.
1319                                                 $out .= $this->parser->insertStripItem( $contextNode->textContent );
1320                                         } else {
1321                                                 # Recover the literal comment in RECOVER_COMMENTS and pre+no-remove
1322                                                 $out .= $contextNode->textContent;
1323                                         }
1324                                 } elseif ( $contextNode->nodeName == 'ignore' ) {
1325                                         # Output suppression used by <includeonly> etc.
1326                                         # OT_WIKI will only respect <ignore> in substed templates.
1327                                         # The other output types respect it unless NO_IGNORE is set.
1328                                         # extractSections() sets NO_IGNORE and so never respects it.
1329                                         if ( ( !isset( $this->parent ) && $this->parser->ot['wiki'] )
1330                                                 || ( $flags & PPFrame::NO_IGNORE )
1331                                         ) {
1332                                                 $out .= $contextNode->textContent;
1333                                         } else {
1334                                                 $out .= '';
1335                                         }
1336                                 } elseif ( $contextNode->nodeName == 'ext' ) {
1337                                         # Extension tag
1338                                         $xpath = new DOMXPath( $contextNode->ownerDocument );
1339                                         $names = $xpath->query( 'name', $contextNode );
1340                                         $attrs = $xpath->query( 'attr', $contextNode );
1341                                         $inners = $xpath->query( 'inner', $contextNode );
1342                                         $closes = $xpath->query( 'close', $contextNode );
1343                                         if ( $flags & PPFrame::NO_TAGS ) {
1344                                                 $s = '<' . $this->expand( $names->item( 0 ), $flags );
1345                                                 if ( $attrs->length > 0 ) {
1346                                                         $s .= $this->expand( $attrs->item( 0 ), $flags );
1347                                                 }
1348                                                 if ( $inners->length > 0 ) {
1349                                                         $s .= '>' . $this->expand( $inners->item( 0 ), $flags );
1350                                                         if ( $closes->length > 0 ) {
1351                                                                 $s .= $this->expand( $closes->item( 0 ), $flags );
1352                                                         }
1353                                                 } else {
1354                                                         $s .= '/>';
1355                                                 }
1356                                                 $out .= $s;
1357                                         } else {
1358                                                 $params = [
1359                                                         'name' => new PPNode_DOM( $names->item( 0 ) ),
1360                                                         'attr' => $attrs->length > 0 ? new PPNode_DOM( $attrs->item( 0 ) ) : null,
1361                                                         'inner' => $inners->length > 0 ? new PPNode_DOM( $inners->item( 0 ) ) : null,
1362                                                         'close' => $closes->length > 0 ? new PPNode_DOM( $closes->item( 0 ) ) : null,
1363                                                 ];
1364                                                 $out .= $this->parser->extensionSubstitution( $params, $this );
1365                                         }
1366                                 } elseif ( $contextNode->nodeName == 'h' ) {
1367                                         # Heading
1368                                         $s = $this->expand( $contextNode->childNodes, $flags );
1369
1370                                         # Insert a heading marker only for <h> children of <root>
1371                                         # This is to stop extractSections from going over multiple tree levels
1372                                         if ( $contextNode->parentNode->nodeName == 'root' && $this->parser->ot['html'] ) {
1373                                                 # Insert heading index marker
1374                                                 $headingIndex = $contextNode->getAttribute( 'i' );
1375                                                 $titleText = $this->title->getPrefixedDBkey();
1376                                                 $this->parser->mHeadings[] = [ $titleText, $headingIndex ];
1377                                                 $serial = count( $this->parser->mHeadings ) - 1;
1378                                                 $marker = Parser::MARKER_PREFIX . "-h-$serial-" . Parser::MARKER_SUFFIX;
1379                                                 $count = $contextNode->getAttribute( 'level' );
1380                                                 $s = substr( $s, 0, $count ) . $marker . substr( $s, $count );
1381                                                 $this->parser->mStripState->addGeneral( $marker, '' );
1382                                         }
1383                                         $out .= $s;
1384                                 } else {
1385                                         # Generic recursive expansion
1386                                         $newIterator = $contextNode->childNodes;
1387                                 }
1388                         } else {
1389                                 throw new MWException( __METHOD__ . ': Invalid parameter type' );
1390                         }
1391
1392                         if ( $newIterator !== false ) {
1393                                 if ( $newIterator instanceof PPNode_DOM ) {
1394                                         $newIterator = $newIterator->node;
1395                                 }
1396                                 $outStack[] = '';
1397                                 $iteratorStack[] = $newIterator;
1398                                 $indexStack[] = 0;
1399                         } elseif ( $iteratorStack[$level] === false ) {
1400                                 // Return accumulated value to parent
1401                                 // With tail recursion
1402                                 while ( $iteratorStack[$level] === false && $level > 0 ) {
1403                                         $outStack[$level - 1] .= $out;
1404                                         array_pop( $outStack );
1405                                         array_pop( $iteratorStack );
1406                                         array_pop( $indexStack );
1407                                         $level--;
1408                                 }
1409                         }
1410                 }
1411                 --$expansionDepth;
1412                 return $outStack[0];
1413         }
1414
1415         /**
1416          * @param string $sep
1417          * @param int $flags
1418          * @param string|PPNode_DOM|DOMDocument $args,...
1419          * @return string
1420          */
1421         public function implodeWithFlags( $sep, $flags /*, ... */ ) {
1422                 $args = array_slice( func_get_args(), 2 );
1423
1424                 $first = true;
1425                 $s = '';
1426                 foreach ( $args as $root ) {
1427                         if ( $root instanceof PPNode_DOM ) {
1428                                 $root = $root->node;
1429                         }
1430                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1431                                 $root = [ $root ];
1432                         }
1433                         foreach ( $root as $node ) {
1434                                 if ( $first ) {
1435                                         $first = false;
1436                                 } else {
1437                                         $s .= $sep;
1438                                 }
1439                                 $s .= $this->expand( $node, $flags );
1440                         }
1441                 }
1442                 return $s;
1443         }
1444
1445         /**
1446          * Implode with no flags specified
1447          * This previously called implodeWithFlags but has now been inlined to reduce stack depth
1448          *
1449          * @param string $sep
1450          * @param string|PPNode_DOM|DOMDocument $args,...
1451          * @return string
1452          */
1453         public function implode( $sep /*, ... */ ) {
1454                 $args = array_slice( func_get_args(), 1 );
1455
1456                 $first = true;
1457                 $s = '';
1458                 foreach ( $args as $root ) {
1459                         if ( $root instanceof PPNode_DOM ) {
1460                                 $root = $root->node;
1461                         }
1462                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1463                                 $root = [ $root ];
1464                         }
1465                         foreach ( $root as $node ) {
1466                                 if ( $first ) {
1467                                         $first = false;
1468                                 } else {
1469                                         $s .= $sep;
1470                                 }
1471                                 $s .= $this->expand( $node );
1472                         }
1473                 }
1474                 return $s;
1475         }
1476
1477         /**
1478          * Makes an object that, when expand()ed, will be the same as one obtained
1479          * with implode()
1480          *
1481          * @param string $sep
1482          * @param string|PPNode_DOM|DOMDocument $args,...
1483          * @return array
1484          */
1485         public function virtualImplode( $sep /*, ... */ ) {
1486                 $args = array_slice( func_get_args(), 1 );
1487                 $out = [];
1488                 $first = true;
1489
1490                 foreach ( $args as $root ) {
1491                         if ( $root instanceof PPNode_DOM ) {
1492                                 $root = $root->node;
1493                         }
1494                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1495                                 $root = [ $root ];
1496                         }
1497                         foreach ( $root as $node ) {
1498                                 if ( $first ) {
1499                                         $first = false;
1500                                 } else {
1501                                         $out[] = $sep;
1502                                 }
1503                                 $out[] = $node;
1504                         }
1505                 }
1506                 return $out;
1507         }
1508
1509         /**
1510          * Virtual implode with brackets
1511          * @param string $start
1512          * @param string $sep
1513          * @param string $end
1514          * @param string|PPNode_DOM|DOMDocument $args,...
1515          * @return array
1516          */
1517         public function virtualBracketedImplode( $start, $sep, $end /*, ... */ ) {
1518                 $args = array_slice( func_get_args(), 3 );
1519                 $out = [ $start ];
1520                 $first = true;
1521
1522                 foreach ( $args as $root ) {
1523                         if ( $root instanceof PPNode_DOM ) {
1524                                 $root = $root->node;
1525                         }
1526                         if ( !is_array( $root ) && !( $root instanceof DOMNodeList ) ) {
1527                                 $root = [ $root ];
1528                         }
1529                         foreach ( $root as $node ) {
1530                                 if ( $first ) {
1531                                         $first = false;
1532                                 } else {
1533                                         $out[] = $sep;
1534                                 }
1535                                 $out[] = $node;
1536                         }
1537                 }
1538                 $out[] = $end;
1539                 return $out;
1540         }
1541
1542         public function __toString() {
1543                 return 'frame{}';
1544         }
1545
1546         public function getPDBK( $level = false ) {
1547                 if ( $level === false ) {
1548                         return $this->title->getPrefixedDBkey();
1549                 } else {
1550                         return $this->titleCache[$level] ?? false;
1551                 }
1552         }
1553
1554         /**
1555          * @return array
1556          */
1557         public function getArguments() {
1558                 return [];
1559         }
1560
1561         /**
1562          * @return array
1563          */
1564         public function getNumberedArguments() {
1565                 return [];
1566         }
1567
1568         /**
1569          * @return array
1570          */
1571         public function getNamedArguments() {
1572                 return [];
1573         }
1574
1575         /**
1576          * Returns true if there are no arguments in this frame
1577          *
1578          * @return bool
1579          */
1580         public function isEmpty() {
1581                 return true;
1582         }
1583
1584         /**
1585          * @param int|string $name
1586          * @return bool Always false in this implementation.
1587          */
1588         public function getArgument( $name ) {
1589                 return false;
1590         }
1591
1592         /**
1593          * Returns true if the infinite loop check is OK, false if a loop is detected
1594          *
1595          * @param Title $title
1596          * @return bool
1597          */
1598         public function loopCheck( $title ) {
1599                 return !isset( $this->loopCheckHash[$title->getPrefixedDBkey()] );
1600         }
1601
1602         /**
1603          * Return true if the frame is a template frame
1604          *
1605          * @return bool
1606          */
1607         public function isTemplate() {
1608                 return false;
1609         }
1610
1611         /**
1612          * Get a title of frame
1613          *
1614          * @return Title
1615          */
1616         public function getTitle() {
1617                 return $this->title;
1618         }
1619
1620         /**
1621          * Set the volatile flag
1622          *
1623          * @param bool $flag
1624          */
1625         public function setVolatile( $flag = true ) {
1626                 $this->volatile = $flag;
1627         }
1628
1629         /**
1630          * Get the volatile flag
1631          *
1632          * @return bool
1633          */
1634         public function isVolatile() {
1635                 return $this->volatile;
1636         }
1637
1638         /**
1639          * Set the TTL
1640          *
1641          * @param int $ttl
1642          */
1643         public function setTTL( $ttl ) {
1644                 if ( $ttl !== null && ( $this->ttl === null || $ttl < $this->ttl ) ) {
1645                         $this->ttl = $ttl;
1646                 }
1647         }
1648
1649         /**
1650          * Get the TTL
1651          *
1652          * @return int|null
1653          */
1654         public function getTTL() {
1655                 return $this->ttl;
1656         }
1657 }
1658
1659 /**
1660  * Expansion frame with template arguments
1661  * @ingroup Parser
1662  */
1663 // phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
1664 class PPTemplateFrame_DOM extends PPFrame_DOM {
1665
1666         public $numberedArgs, $namedArgs;
1667
1668         /**
1669          * @var PPFrame_DOM
1670          */
1671         public $parent;
1672         public $numberedExpansionCache, $namedExpansionCache;
1673
1674         /**
1675          * @param Preprocessor $preprocessor
1676          * @param bool|PPFrame_DOM $parent
1677          * @param array $numberedArgs
1678          * @param array $namedArgs
1679          * @param bool|Title $title
1680          */
1681         public function __construct( $preprocessor, $parent = false, $numberedArgs = [],
1682                 $namedArgs = [], $title = false
1683         ) {
1684                 parent::__construct( $preprocessor );
1685
1686                 $this->parent = $parent;
1687                 $this->numberedArgs = $numberedArgs;
1688                 $this->namedArgs = $namedArgs;
1689                 $this->title = $title;
1690                 $pdbk = $title ? $title->getPrefixedDBkey() : false;
1691                 $this->titleCache = $parent->titleCache;
1692                 $this->titleCache[] = $pdbk;
1693                 $this->loopCheckHash = /*clone*/ $parent->loopCheckHash;
1694                 if ( $pdbk !== false ) {
1695                         $this->loopCheckHash[$pdbk] = true;
1696                 }
1697                 $this->depth = $parent->depth + 1;
1698                 $this->numberedExpansionCache = $this->namedExpansionCache = [];
1699         }
1700
1701         public function __toString() {
1702                 $s = 'tplframe{';
1703                 $first = true;
1704                 $args = $this->numberedArgs + $this->namedArgs;
1705                 foreach ( $args as $name => $value ) {
1706                         if ( $first ) {
1707                                 $first = false;
1708                         } else {
1709                                 $s .= ', ';
1710                         }
1711                         $s .= "\"$name\":\"" .
1712                                 str_replace( '"', '\\"', $value->ownerDocument->saveXML( $value ) ) . '"';
1713                 }
1714                 $s .= '}';
1715                 return $s;
1716         }
1717
1718         /**
1719          * @throws MWException
1720          * @param string|int $key
1721          * @param string|PPNode_DOM|DOMDocument $root
1722          * @param int $flags
1723          * @return string
1724          */
1725         public function cachedExpand( $key, $root, $flags = 0 ) {
1726                 if ( isset( $this->parent->childExpansionCache[$key] ) ) {
1727                         return $this->parent->childExpansionCache[$key];
1728                 }
1729                 $retval = $this->expand( $root, $flags );
1730                 if ( !$this->isVolatile() ) {
1731                         $this->parent->childExpansionCache[$key] = $retval;
1732                 }
1733                 return $retval;
1734         }
1735
1736         /**
1737          * Returns true if there are no arguments in this frame
1738          *
1739          * @return bool
1740          */
1741         public function isEmpty() {
1742                 return !count( $this->numberedArgs ) && !count( $this->namedArgs );
1743         }
1744
1745         public function getArguments() {
1746                 $arguments = [];
1747                 foreach ( array_merge(
1748                                 array_keys( $this->numberedArgs ),
1749                                 array_keys( $this->namedArgs ) ) as $key ) {
1750                         $arguments[$key] = $this->getArgument( $key );
1751                 }
1752                 return $arguments;
1753         }
1754
1755         public function getNumberedArguments() {
1756                 $arguments = [];
1757                 foreach ( array_keys( $this->numberedArgs ) as $key ) {
1758                         $arguments[$key] = $this->getArgument( $key );
1759                 }
1760                 return $arguments;
1761         }
1762
1763         public function getNamedArguments() {
1764                 $arguments = [];
1765                 foreach ( array_keys( $this->namedArgs ) as $key ) {
1766                         $arguments[$key] = $this->getArgument( $key );
1767                 }
1768                 return $arguments;
1769         }
1770
1771         /**
1772          * @param int $index
1773          * @return string|bool
1774          */
1775         public function getNumberedArgument( $index ) {
1776                 if ( !isset( $this->numberedArgs[$index] ) ) {
1777                         return false;
1778                 }
1779                 if ( !isset( $this->numberedExpansionCache[$index] ) ) {
1780                         # No trimming for unnamed arguments
1781                         $this->numberedExpansionCache[$index] = $this->parent->expand(
1782                                 $this->numberedArgs[$index],
1783                                 PPFrame::STRIP_COMMENTS
1784                         );
1785                 }
1786                 return $this->numberedExpansionCache[$index];
1787         }
1788
1789         /**
1790          * @param string $name
1791          * @return string|bool
1792          */
1793         public function getNamedArgument( $name ) {
1794                 if ( !isset( $this->namedArgs[$name] ) ) {
1795                         return false;
1796                 }
1797                 if ( !isset( $this->namedExpansionCache[$name] ) ) {
1798                         # Trim named arguments post-expand, for backwards compatibility
1799                         $this->namedExpansionCache[$name] = trim(
1800                                 $this->parent->expand( $this->namedArgs[$name], PPFrame::STRIP_COMMENTS ) );
1801                 }
1802                 return $this->namedExpansionCache[$name];
1803         }
1804
1805         /**
1806          * @param int|string $name
1807          * @return string|bool
1808          */
1809         public function getArgument( $name ) {
1810                 $text = $this->getNumberedArgument( $name );
1811                 if ( $text === false ) {
1812                         $text = $this->getNamedArgument( $name );
1813                 }
1814                 return $text;
1815         }
1816
1817         /**
1818          * Return true if the frame is a template frame
1819          *
1820          * @return bool
1821          */
1822         public function isTemplate() {
1823                 return true;
1824         }
1825
1826         public function setVolatile( $flag = true ) {
1827                 parent::setVolatile( $flag );
1828                 $this->parent->setVolatile( $flag );
1829         }
1830
1831         public function setTTL( $ttl ) {
1832                 parent::setTTL( $ttl );
1833                 $this->parent->setTTL( $ttl );
1834         }
1835 }
1836
1837 /**
1838  * Expansion frame with custom arguments
1839  * @ingroup Parser
1840  */
1841 // phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
1842 class PPCustomFrame_DOM extends PPFrame_DOM {
1843
1844         public $args;
1845
1846         public function __construct( $preprocessor, $args ) {
1847                 parent::__construct( $preprocessor );
1848                 $this->args = $args;
1849         }
1850
1851         public function __toString() {
1852                 $s = 'cstmframe{';
1853                 $first = true;
1854                 foreach ( $this->args as $name => $value ) {
1855                         if ( $first ) {
1856                                 $first = false;
1857                         } else {
1858                                 $s .= ', ';
1859                         }
1860                         $s .= "\"$name\":\"" .
1861                                 str_replace( '"', '\\"', $value->__toString() ) . '"';
1862                 }
1863                 $s .= '}';
1864                 return $s;
1865         }
1866
1867         /**
1868          * @return bool
1869          */
1870         public function isEmpty() {
1871                 return !count( $this->args );
1872         }
1873
1874         /**
1875          * @param int|string $index
1876          * @return string|bool
1877          */
1878         public function getArgument( $index ) {
1879                 if ( !isset( $this->args[$index] ) ) {
1880                         return false;
1881                 }
1882                 return $this->args[$index];
1883         }
1884
1885         public function getArguments() {
1886                 return $this->args;
1887         }
1888 }
1889
1890 /**
1891  * @ingroup Parser
1892  */
1893 // phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
1894 class PPNode_DOM implements PPNode {
1895
1896         /**
1897          * @var DOMElement
1898          */
1899         public $node;
1900         public $xpath;
1901
1902         public function __construct( $node, $xpath = false ) {
1903                 $this->node = $node;
1904         }
1905
1906         /**
1907          * @return DOMXPath
1908          */
1909         public function getXPath() {
1910                 if ( $this->xpath === null ) {
1911                         $this->xpath = new DOMXPath( $this->node->ownerDocument );
1912                 }
1913                 return $this->xpath;
1914         }
1915
1916         public function __toString() {
1917                 if ( $this->node instanceof DOMNodeList ) {
1918                         $s = '';
1919                         foreach ( $this->node as $node ) {
1920                                 $s .= $node->ownerDocument->saveXML( $node );
1921                         }
1922                 } else {
1923                         $s = $this->node->ownerDocument->saveXML( $this->node );
1924                 }
1925                 return $s;
1926         }
1927
1928         /**
1929          * @return bool|PPNode_DOM
1930          */
1931         public function getChildren() {
1932                 return $this->node->childNodes ? new self( $this->node->childNodes ) : false;
1933         }
1934
1935         /**
1936          * @return bool|PPNode_DOM
1937          */
1938         public function getFirstChild() {
1939                 return $this->node->firstChild ? new self( $this->node->firstChild ) : false;
1940         }
1941
1942         /**
1943          * @return bool|PPNode_DOM
1944          */
1945         public function getNextSibling() {
1946                 return $this->node->nextSibling ? new self( $this->node->nextSibling ) : false;
1947         }
1948
1949         /**
1950          * @param string $type
1951          *
1952          * @return bool|PPNode_DOM
1953          */
1954         public function getChildrenOfType( $type ) {
1955                 return new self( $this->getXPath()->query( $type, $this->node ) );
1956         }
1957
1958         /**
1959          * @return int
1960          */
1961         public function getLength() {
1962                 if ( $this->node instanceof DOMNodeList ) {
1963                         return $this->node->length;
1964                 } else {
1965                         return false;
1966                 }
1967         }
1968
1969         /**
1970          * @param int $i
1971          * @return bool|PPNode_DOM
1972          */
1973         public function item( $i ) {
1974                 $item = $this->node->item( $i );
1975                 return $item ? new self( $item ) : false;
1976         }
1977
1978         /**
1979          * @return string
1980          */
1981         public function getName() {
1982                 if ( $this->node instanceof DOMNodeList ) {
1983                         return '#nodelist';
1984                 } else {
1985                         return $this->node->nodeName;
1986                 }
1987         }
1988
1989         /**
1990          * Split a "<part>" node into an associative array containing:
1991          *  - name          PPNode name
1992          *  - index         String index
1993          *  - value         PPNode value
1994          *
1995          * @throws MWException
1996          * @return array
1997          */
1998         public function splitArg() {
1999                 $xpath = $this->getXPath();
2000                 $names = $xpath->query( 'name', $this->node );
2001                 $values = $xpath->query( 'value', $this->node );
2002                 if ( !$names->length || !$values->length ) {
2003                         throw new MWException( 'Invalid brace node passed to ' . __METHOD__ );
2004                 }
2005                 $name = $names->item( 0 );
2006                 $index = $name->getAttribute( 'index' );
2007                 return [
2008                         'name' => new self( $name ),
2009                         'index' => $index,
2010                         'value' => new self( $values->item( 0 ) ) ];
2011         }
2012
2013         /**
2014          * Split an "<ext>" node into an associative array containing name, attr, inner and close
2015          * All values in the resulting array are PPNodes. Inner and close are optional.
2016          *
2017          * @throws MWException
2018          * @return array
2019          */
2020         public function splitExt() {
2021                 $xpath = $this->getXPath();
2022                 $names = $xpath->query( 'name', $this->node );
2023                 $attrs = $xpath->query( 'attr', $this->node );
2024                 $inners = $xpath->query( 'inner', $this->node );
2025                 $closes = $xpath->query( 'close', $this->node );
2026                 if ( !$names->length || !$attrs->length ) {
2027                         throw new MWException( 'Invalid ext node passed to ' . __METHOD__ );
2028                 }
2029                 $parts = [
2030                         'name' => new self( $names->item( 0 ) ),
2031                         'attr' => new self( $attrs->item( 0 ) ) ];
2032                 if ( $inners->length ) {
2033                         $parts['inner'] = new self( $inners->item( 0 ) );
2034                 }
2035                 if ( $closes->length ) {
2036                         $parts['close'] = new self( $closes->item( 0 ) );
2037                 }
2038                 return $parts;
2039         }
2040
2041         /**
2042          * Split a "<h>" node
2043          * @throws MWException
2044          * @return array
2045          */
2046         public function splitHeading() {
2047                 if ( $this->getName() !== 'h' ) {
2048                         throw new MWException( 'Invalid h node passed to ' . __METHOD__ );
2049                 }
2050                 return [
2051                         'i' => $this->node->getAttribute( 'i' ),
2052                         'level' => $this->node->getAttribute( 'level' ),
2053                         'contents' => $this->getChildren()
2054                 ];
2055         }
2056 }