includes/parser/Preprocessor_Hash.php
<?php
/**
* Preprocessor using PHP arrays
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup Parser
*/
use MediaWiki\Parser\Parser;
/**
* Differences from DOM schema:
* * attribute nodes are children
* * "<h>" nodes that aren't at the top are replaced with <possible-h>
*
* Nodes are stored in a recursive array data structure. A node store is an
* array where each element may be either a scalar (representing a text node)
* or a "descriptor", which is a two-element array where the first element is
* the node name and the second element is the node store for the children.
*
* Attributes are represented as children that have a node name starting with
* "@", and a single text node child.
*
* @todo: Consider replacing descriptor arrays with objects of a new class.
* Benchmark and measure resulting memory impact.
*
* @ingroup Parser
*/
// phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
class Preprocessor_Hash extends Preprocessor {
/** Cache format version */
protected const CACHE_VERSION = 4;
/** @var int|false Min wikitext size for which to cache DOM tree */
protected $cacheThreshold;
/**
* @see Preprocessor::__construct()
* @param Parser $parser
* @param WANObjectCache|null $wanCache
* @param array $options Additional options include:
* - cacheThreshold: min text size for which to cache DOMs. [Default: false]
*/
public function __construct(
Parser $parser,
WANObjectCache $wanCache = null,
array $options = []
) {
parent::__construct( $parser, $wanCache, $options );
$this->cacheThreshold = $options['cacheThreshold'] ?? false;
}
/**
* @return PPFrame_Hash
*/
public function newFrame() {
return new PPFrame_Hash( $this );
}
/**
* @param array $args
* @return PPCustomFrame_Hash
*/
public function newCustomFrame( $args ) {
return new PPCustomFrame_Hash( $this, $args );
}
/**
* @param array $values
* @return PPNode_Hash_Array
*/
public function newPartNodeArray( $values ) {
$list = [];
foreach ( $values as $k => $val ) {
if ( is_int( $k ) ) {
$store = [ [ 'part', [
[ 'name', [ [ '@index', [ $k ] ] ] ],
[ 'value', [ strval( $val ) ] ],
] ] ];
} else {
$store = [ [ 'part', [
[ 'name', [ strval( $k ) ] ],
'=',
[ 'value', [ strval( $val ) ] ],
] ] ];
}
$list[] = new PPNode_Hash_Tree( $store, 0 );
}
return new PPNode_Hash_Array( $list );
}
public function preprocessToObj( $text, $flags = 0 ) {
if ( $this->disableLangConversion ) {
// Language conversions are globally disabled; implicitly set flag
$flags |= self::DOM_LANG_CONVERSION_DISABLED;
}
$domTreeArray = null;
if (
$this->cacheThreshold !== false &&
strlen( $text ) >= $this->cacheThreshold &&
( $flags & self::DOM_UNCACHED ) != self::DOM_UNCACHED
) {
$domTreeJson = $this->wanCache->getWithSetCallback(
$this->wanCache->makeKey( 'preprocess-hash', sha1( $text ), $flags ),
$this->wanCache::TTL_DAY,
function () use ( $text, $flags, &$domTreeArray ) {
$domTreeArray = $this->buildDomTreeArrayFromText( $text, $flags );
return json_encode(
$domTreeArray,
JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE
);
},
[ 'version' => self::CACHE_VERSION, 'segmentable' => true ]
);
$domTreeArray ??= json_decode( $domTreeJson );
}
$domTreeArray ??= $this->buildDomTreeArrayFromText( $text, $flags );
return new PPNode_Hash_Tree( $domTreeArray, 0 );
}
/**
* @param string $text Wikitext
* @param int $flags Bit field of Preprocessor::DOM_* flags
* @return array JSON-serializable document object model array
*/
private function buildDomTreeArrayFromText( $text, $flags ) {
$forInclusion = ( $flags & self::DOM_FOR_INCLUSION );
$langConversionDisabled = ( $flags & self::DOM_LANG_CONVERSION_DISABLED );
$xmlishElements = $this->parser->getStripList();
$xmlishAllowMissingEndTag = [ 'includeonly', 'noinclude', 'onlyinclude' ];
$enableOnlyinclude = false;
if ( $forInclusion ) {
$ignoredTags = [ 'includeonly', '/includeonly' ];
$ignoredElements = [ 'noinclude' ];
$xmlishElements[] = 'noinclude';
if ( str_contains( $text, '<onlyinclude>' )
&& str_contains( $text, '</onlyinclude>' )
) {
$enableOnlyinclude = true;
}
} else {
$ignoredTags = [ 'noinclude', '/noinclude', 'onlyinclude', '/onlyinclude' ];
$ignoredElements = [ 'includeonly' ];
$xmlishElements[] = 'includeonly';
}
$xmlishRegex = implode( '|', array_merge( $xmlishElements, $ignoredTags ) );
// Use "A" modifier (anchored) instead of "^", because ^ doesn't work with an offset
$elementsRegex = "~(?:$xmlishRegex)(?=\s|\/>|>)|!--~iA";
$stack = new PPDStack_Hash;
$searchBase = "[{<\n";
if ( !$langConversionDisabled ) {
$searchBase .= '-';
}
// For fast reverse searches
$revText = strrev( $text );
$lengthText = strlen( $text );
// Input pointer, starts out pointing to a pseudo-newline before the start
$i = 0;
// Current accumulator. See the doc comment for Preprocessor_Hash for the format.
$accum =& $stack->getAccum();
// True to find equals signs in arguments
$findEquals = false;
// True to take notice of pipe characters
$findPipe = false;
$headingIndex = 1;
// True if $i is inside a possible heading
$inHeading = false;
// True if there are no more greater-than (>) signs right of $i
$noMoreGT = false;
// Map of tag name => true if there are no more closing tags of given type right of $i
$noMoreClosingTag = [];
// True to ignore all input up to the next <onlyinclude>
$findOnlyinclude = $enableOnlyinclude;
// Do a line-start run without outputting an LF character
$fakeLineStart = true;
while ( true ) {
if ( $findOnlyinclude ) {
// Ignore all input up to the next <onlyinclude>
$startPos = strpos( $text, '<onlyinclude>', $i );
if ( $startPos === false ) {
// Ignored section runs to the end
$accum[] = [ 'ignore', [ substr( $text, $i ) ] ];
break;
}
$tagEndPos = $startPos + 13; // past-the-end of <onlyinclude>
$accum[] = [ 'ignore', [ substr( $text, $i, $tagEndPos - $i ) ] ];
$i = $tagEndPos;
$findOnlyinclude = false;
}
if ( $fakeLineStart ) {
$found = 'line-start';
$curChar = '';
} else {
# Find next opening brace, closing brace or pipe
$search = $searchBase;
if ( $stack->top === false ) {
$currentClosing = '';
} else {
$currentClosing = $stack->top->close;
$search .= $currentClosing;
}
if ( $findPipe ) {
$search .= '|';
}
if ( $findEquals ) {
// First equals will be for the template
$search .= '=';
}
$rule = null;
# Output literal section, advance input counter
$literalLength = strcspn( $text, $search, $i );
if ( $literalLength > 0 ) {
self::addLiteral( $accum, substr( $text, $i, $literalLength ) );
$i += $literalLength;
}
if ( $i >= $lengthText ) {
if ( $currentClosing === "\n" ) {
// Do a past-the-end run to finish off the heading
$curChar = '';
$found = 'line-end';
} else {
# All done
break;
}
} else {
$curChar = $curTwoChar = $text[$i];
if ( $i + 1 < $lengthText ) {
$curTwoChar .= $text[$i + 1];
}
if ( $curChar === '|' ) {
$found = 'pipe';
} elseif ( $curChar === '=' ) {
$found = 'equals';
} elseif ( $curChar === '<' ) {
$found = 'angle';
} elseif ( $curChar === "\n" ) {
if ( $inHeading ) {
$found = 'line-end';
} else {
$found = 'line-start';
}
} elseif ( $curTwoChar === $currentClosing ) {
$found = 'close';
$curChar = $curTwoChar;
} elseif ( $curChar === $currentClosing ) {
$found = 'close';
} elseif ( isset( $this->rules[$curTwoChar] ) ) {
$curChar = $curTwoChar;
$found = 'open';
$rule = $this->rules[$curChar];
} elseif ( isset( $this->rules[$curChar] ) ) {
$found = 'open';
$rule = $this->rules[$curChar];
} else {
# Some versions of PHP have a strcspn which stops on
# null characters; ignore these and continue.
# We also may get '-' and '}' characters here which
# don't match -{ or $currentClosing. Add these to
# output and continue.
if ( $curChar === '-' || $curChar === '}' ) {
self::addLiteral( $accum, $curChar );
}
++$i;
continue;
}
}
}
if ( $found === 'angle' ) {
// Handle </onlyinclude>
if ( $enableOnlyinclude
&& substr_compare( $text, '</onlyinclude>', $i, 14 ) === 0
) {
$findOnlyinclude = true;
continue;
}
// Determine element name
if ( !preg_match( $elementsRegex, $text, $matches, 0, $i + 1 ) ) {
// Element name missing or not listed
self::addLiteral( $accum, '<' );
++$i;
continue;
}
$name = $matches[0];
// Handle comments
if ( $name === '!--' ) {
// To avoid leaving blank lines, when a sequence of
// space-separated comments is both preceded and followed by
// a newline (ignoring spaces), then
// trim leading and trailing spaces and the trailing newline.
// Find the end
$endPos = strpos( $text, '-->', $i + 4 );
if ( $endPos === false ) {
// Unclosed comment in input, runs to end
$inner = substr( $text, $i );
$accum[] = [ 'comment', [ $inner ] ];
$i = $lengthText;
} else {
// Search backwards for leading whitespace
// $wsStart is the first char of the comment (first of the leading space or '<')
$wsStart = $i ? ( $i - strspn( $revText, " \t", $lengthText - $i ) ) : 0;
// $wsEnd will be the char *after* the comment (after last space or the '>' if there's no space)
$wsEnd = $endPos + 3; // add length of -->
// Search forwards for trailing whitespace
$wsEnd += strspn( $text, " \t", $wsEnd );
// Keep looking forward as long as we're finding more comments on the line
$comments = [ [ $wsStart, $wsEnd ] ];
while ( substr_compare( $text, '<!--', $wsEnd, 4 ) === 0 ) {
$c = strpos( $text, '-->', $wsEnd + 4 );
if ( $c === false ) {
break;
}
$c += 3; // add length of -->
// Search forwards for trailing whitespace
$c += strspn( $text, " \t", $c );
$comments[] = [ $wsEnd, $c ];
$wsEnd = $c;
}
// Eat the line if possible
// TODO: This could theoretically be done if $wsStart === 0, i.e. for comments at
// the overall start. That's not how Sanitizer::removeHTMLcomments() did it, but
// it's a possible beneficial b/c break.
if ( $wsStart > 0 && substr_compare( $text, "\n", $wsStart - 1, 1 ) === 0
&& substr_compare( $text, "\n", $wsEnd, 1 ) === 0
) {
// Remove leading whitespace from the end of the accumulator
$wsLength = $i - $wsStart;
$endIndex = count( $accum ) - 1;
if ( $wsLength > 0
&& $endIndex >= 0
&& is_string( $accum[$endIndex] )
&& strspn( $accum[$endIndex], " \t", -$wsLength ) === $wsLength
) {
$accum[$endIndex] = substr( $accum[$endIndex], 0, -$wsLength );
}
// Dump all but the last comment to the accumulator
// $endPos includes the newline from the if above, want also eat that
[ $startPos, $endPos ] = array_pop( $comments );
foreach ( $comments as [ $cStartPos, $cEndPos ] ) {
// $cEndPos is the next char, no +1 needed to get correct length between start/end
$inner = substr( $text, $cStartPos, $cEndPos - $cStartPos );
$accum[] = [ 'comment', [ $inner ] ];
}
// Do a line-start run next time to look for headings after the comment
$fakeLineStart = true;
} else {
// No line to eat, just take the comment itself
$startPos = $i;
$endPos += 2;
}
if ( $stack->top ) {
$part = $stack->top->getCurrentPart();
if ( $part->commentEnd !== $wsStart - 1 ) {
$part->visualEnd = $wsStart;
}
// Else comments abutting, no change in visual end
$part->commentEnd = $endPos;
}
$i = $endPos + 1;
$inner = substr( $text, $startPos, $endPos - $startPos + 1 );
$accum[] = [ 'comment', [ $inner ] ];
}
continue;
}
$attrStart = $i + strlen( $name ) + 1;
// Find end of tag
$tagEndPos = $noMoreGT ? false : strpos( $text, '>', $attrStart );
if ( $tagEndPos === false ) {
// Infinite backtrack
// Disable tag search to prevent worst-case O(N^2) performance
$noMoreGT = true;
self::addLiteral( $accum, '<' );
++$i;
continue;
}
$lowerName = strtolower( $name );
// Handle ignored tags
if ( in_array( $lowerName, $ignoredTags ) ) {
$accum[] = [ 'ignore', [ substr( $text, $i, $tagEndPos - $i + 1 ) ] ];
$i = $tagEndPos + 1;
continue;
}
$tagStartPos = $i;
if ( $text[$tagEndPos - 1] === '/' ) {
// Short end tag
$attrEnd = $tagEndPos - 1;
$inner = null;
$i = $tagEndPos + 1;
$close = null;
} else {
$attrEnd = $tagEndPos;
// Find closing tag
if (
!isset( $noMoreClosingTag[$lowerName] ) &&
preg_match( "/<\/" . preg_quote( $name, '/' ) . "\s*>/i",
$text, $matches, PREG_OFFSET_CAPTURE, $tagEndPos + 1 )
) {
[ $close, $closeTagStartPos ] = $matches[0];
$inner = substr( $text, $tagEndPos + 1, $closeTagStartPos - $tagEndPos - 1 );
$i = $closeTagStartPos + strlen( $close );
} else {
// No end tag
if ( in_array( $name, $xmlishAllowMissingEndTag ) ) {
// Let it run out to the end of the text.
$inner = substr( $text, $tagEndPos + 1 );
$i = $lengthText;
$close = null;
} else {
// Don't match the tag, treat opening tag as literal and resume parsing.
$i = $tagEndPos + 1;
self::addLiteral( $accum, substr( $text, $tagStartPos, $tagEndPos + 1 - $tagStartPos ) );
// Cache results, otherwise we have O(N^2) performance for input like <foo><foo><foo>...
$noMoreClosingTag[$lowerName] = true;
continue;
}
}
}
// <includeonly> and <noinclude> just become <ignore> tags
if ( in_array( $lowerName, $ignoredElements ) ) {
$accum[] = [ 'ignore', [ substr( $text, $tagStartPos, $i - $tagStartPos ) ] ];
continue;
}
if ( $attrEnd <= $attrStart ) {
$attr = '';
} else {
// Note that the attr element contains the whitespace between name and attribute,
// this is necessary for precise reconstruction during pre-save transform.
$attr = substr( $text, $attrStart, $attrEnd - $attrStart );
}
$children = [
[ 'name', [ $name ] ],
[ 'attr', [ $attr ] ],
];
if ( $inner !== null ) {
$children[] = [ 'inner', [ $inner ] ];
}
if ( $close !== null ) {
$children[] = [ 'close', [ $close ] ];
}
$accum[] = [ 'ext', $children ];
} elseif ( $found === 'line-start' ) {
// Is this the start of a heading?
// Line break belongs before the heading element in any case
if ( $fakeLineStart ) {
$fakeLineStart = false;
} else {
self::addLiteral( $accum, $curChar );
$i++;
}
// Examine upto 6 characters
$count = strspn( $text, '=', $i, min( $lengthText, 6 ) );
if ( $count === 1 && $findEquals ) {
// DWIM: This looks kind of like a name/value separator.
// Let's let the equals handler have it and break the potential
// heading. This is heuristic, but AFAICT the methods for
// completely correct disambiguation are very complex.
} elseif ( $count > 0 ) {
$piece = [
'open' => "\n",
'close' => "\n",
'parts' => [ new PPDPart_Hash( str_repeat( '=', $count ) ) ],
'startPos' => $i,
'count' => $count,
];
$stack->push( $piece );
$accum =& $stack->getAccum();
$stackFlags = $stack->getFlags();
if ( isset( $stackFlags['findEquals'] ) ) {
$findEquals = $stackFlags['findEquals'];
}
if ( isset( $stackFlags['findPipe'] ) ) {
$findPipe = $stackFlags['findPipe'];
}
if ( isset( $stackFlags['inHeading'] ) ) {
$inHeading = $stackFlags['inHeading'];
}
$i += $count;
}
} elseif ( $found === 'line-end' ) {
$piece = $stack->top;
// A heading must be open, otherwise \n wouldn't have been in the search list
// FIXME: Don't use assert()
// phpcs:ignore MediaWiki.Usage.ForbiddenFunctions.assert
assert( $piece->open === "\n" );
$part = $piece->getCurrentPart();
// Search back through the input to see if it has a proper close.
// Do this using the reversed string since the other solutions
// (end anchor, etc.) are inefficient.
$wsLength = strspn( $revText, " \t", $lengthText - $i );
$searchStart = $i - $wsLength;
if ( $part->commentEnd === $searchStart - 1 ) {
// Comment found at line end
// Search for equals signs before the comment
$searchStart = $part->visualEnd;
$searchStart -= strspn( $revText, " \t", $lengthText - $searchStart );
}
$equalsLength = strspn( $revText, '=', $lengthText - $searchStart );
if ( $equalsLength > 0 ) {
if ( $searchStart - $equalsLength === $piece->startPos ) {
// This is just a single string of equals signs on its own line
// Replicate the doHeadings behavior /={count}(.+)={count}/
// First find out how many equals signs there really are (don't stop at 6)
if ( $equalsLength < 3 ) {
$count = 0;
} else {
$count = min( 6, intval( ( $equalsLength - 1 ) / 2 ) );
}
} else {
$count = min( $equalsLength, $piece->count );
}
if ( $count > 0 ) {
// Normal match, output <h>
$element = [ [ 'possible-h',
array_merge(
[
[ '@level', [ $count ] ],
[ '@i', [ $headingIndex++ ] ]
],
$accum
)
] ];
} else {
// Single equals sign on its own line, count=0
$element = $accum;
}
} else {
// No match, no <h>, just pass down the inner text
$element = $accum;
}
// Unwind the stack
$stack->pop();
$accum =& $stack->getAccum();
$stackFlags = $stack->getFlags();
if ( isset( $stackFlags['findEquals'] ) ) {
$findEquals = $stackFlags['findEquals'];
}
if ( isset( $stackFlags['findPipe'] ) ) {
$findPipe = $stackFlags['findPipe'];
}
if ( isset( $stackFlags['inHeading'] ) ) {
$inHeading = $stackFlags['inHeading'];
}
// Append the result to the enclosing accumulator
array_splice( $accum, count( $accum ), 0, $element );
// Note that we do NOT increment the input pointer.
// This is because the closing linebreak could be the opening linebreak of
// another heading. Infinite loops are avoided because the next iteration MUST
// hit the heading open case above, which unconditionally increments the
// input pointer.
} elseif ( $found === 'open' ) {
# count opening brace characters
$curLen = strlen( $curChar );
$count = $curLen > 1
# allow the final character to repeat
? strspn( $text, $curChar[$curLen - 1], $i + 1 ) + 1
: strspn( $text, $curChar, $i );
$savedPrefix = '';
$lineStart = $i > 0 && $text[$i - 1] === "\n";
if ( $curChar === "-{" && $count > $curLen ) {
// -{ => {{ transition because rightmost wins
$savedPrefix = '-';
$i++;
$curChar = '{';
$count--;
$rule = $this->rules[$curChar];
}
# we need to add to stack only if opening brace count is enough for one of the rules
if ( $count >= $rule['min'] ) {
# Add it to the stack
$piece = [
'open' => $curChar,
'close' => $rule['end'],
'savedPrefix' => $savedPrefix,
'count' => $count,
'lineStart' => $lineStart,
];
$stack->push( $piece );
$accum =& $stack->getAccum();
$stackFlags = $stack->getFlags();
if ( isset( $stackFlags['findEquals'] ) ) {
$findEquals = $stackFlags['findEquals'];
}
if ( isset( $stackFlags['findPipe'] ) ) {
$findPipe = $stackFlags['findPipe'];
}
if ( isset( $stackFlags['inHeading'] ) ) {
$inHeading = $stackFlags['inHeading'];
}
} else {
# Add literal brace(s)
self::addLiteral( $accum, $savedPrefix . str_repeat( $curChar, $count ) );
}
$i += $count;
} elseif ( $found === 'close' ) {
/** @var PPDStackElement_Hash $piece */
$piece = $stack->top;
'@phan-var PPDStackElement_Hash $piece';
# lets check if there are enough characters for closing brace
$maxCount = $piece->count;
if ( $piece->close === '}-' && $curChar === '}' ) {
$maxCount--; # don't try to match closing '-' as a '}'
}
$curLen = strlen( $curChar );
$count = $curLen > 1
? $curLen
: strspn( $text, $curChar, $i, $maxCount );
# check for maximum matching characters (if there are 5 closing
# characters, we will probably need only 3 - depending on the rules)
$rule = $this->rules[$piece->open];
if ( $count > $rule['max'] ) {
# The specified maximum exists in the callback array, unless the caller
# has made an error
$matchingCount = $rule['max'];
} else {
# Count is less than the maximum
# Skip any gaps in the callback array to find the true largest match
# Need to use array_key_exists not isset because the callback can be null
$matchingCount = $count;
while ( $matchingCount > 0 && !array_key_exists( $matchingCount, $rule['names'] ) ) {
--$matchingCount;
}
}
if ( $matchingCount <= 0 ) {
# No matching element found in callback array
# Output a literal closing brace and continue
$endText = substr( $text, $i, $count );
self::addLiteral( $accum, $endText );
$i += $count;
continue;
}
// @phan-suppress-next-line PhanTypeArraySuspiciousNullable
$name = $rule['names'][$matchingCount];
if ( $name === null ) {
// No element, just literal text
$endText = substr( $text, $i, $matchingCount );
$element = $piece->breakSyntax( $matchingCount );
self::addLiteral( $element, $endText );
} else {
# Create XML element
$parts = $piece->parts;
$titleAccum = $parts[0]->out;
unset( $parts[0] );
$children = [];
# The invocation is at the start of the line if lineStart is set in
# the stack, and all opening brackets are used up.
if ( $maxCount === $matchingCount &&
$piece->lineStart &&
$piece->savedPrefix === ''
) {
$children[] = [ '@lineStart', [ 1 ] ];
}
$titleNode = [ 'title', $titleAccum ];
$children[] = $titleNode;
$argIndex = 1;
foreach ( $parts as $part ) {
if ( isset( $part->eqpos ) ) {
$equalsNode = $part->out[$part->eqpos];
$nameNode = [ 'name', array_slice( $part->out, 0, $part->eqpos ) ];
$valueNode = [ 'value', array_slice( $part->out, $part->eqpos + 1 ) ];
$partNode = [ 'part', [ $nameNode, $equalsNode, $valueNode ] ];
$children[] = $partNode;
} else {
$nameNode = [ 'name', [ [ '@index', [ $argIndex++ ] ] ] ];
$valueNode = [ 'value', $part->out ];
$partNode = [ 'part', [ $nameNode, $valueNode ] ];
$children[] = $partNode;
}
}
$element = [ [ $name, $children ] ];
}
# Advance input pointer
$i += $matchingCount;
# Unwind the stack
$stack->pop();
$accum =& $stack->getAccum();
# Re-add the old stack element if it still has unmatched opening characters remaining
if ( $matchingCount < $piece->count ) {
$piece->parts = [ new PPDPart_Hash ];
$piece->count -= $matchingCount;
# do we still qualify for any callback with remaining count?
$min = $this->rules[$piece->open]['min'];
if ( $piece->count >= $min ) {
$stack->push( $piece );
$accum =& $stack->getAccum();
} elseif ( $piece->count === 1 && $piece->open === '{' && $piece->savedPrefix === '-' ) {
$piece->savedPrefix = '';
$piece->open = '-{';
$piece->count = 2;
$piece->close = $this->rules[$piece->open]['end'];
$stack->push( $piece );
$accum =& $stack->getAccum();
} else {
$s = substr( $piece->open, 0, -1 );
$s .= str_repeat(
substr( $piece->open, -1 ),
$piece->count - strlen( $s )
);
self::addLiteral( $accum, $piece->savedPrefix . $s );
}
} elseif ( $piece->savedPrefix !== '' ) {
self::addLiteral( $accum, $piece->savedPrefix );
}
$stackFlags = $stack->getFlags();
if ( isset( $stackFlags['findEquals'] ) ) {
$findEquals = $stackFlags['findEquals'];
}
if ( isset( $stackFlags['findPipe'] ) ) {
$findPipe = $stackFlags['findPipe'];
}
if ( isset( $stackFlags['inHeading'] ) ) {
$inHeading = $stackFlags['inHeading'];
}
# Add XML element to the enclosing accumulator
array_splice( $accum, count( $accum ), 0, $element );
} elseif ( $found === 'pipe' ) {
$findEquals = true; // shortcut for getFlags()
$stack->addPart();
$accum =& $stack->getAccum();
++$i;
} elseif ( $found === 'equals' ) {
$findEquals = false; // shortcut for getFlags()
$accum[] = [ 'equals', [ '=' ] ];
$stack->getCurrentPart()->eqpos = count( $accum ) - 1;
++$i;
}
}
# Output any remaining unclosed brackets
foreach ( $stack->stack as $piece ) {
array_splice( $stack->rootAccum, count( $stack->rootAccum ), 0, $piece->breakSyntax() );
}
# Enable top-level headings
foreach ( $stack->rootAccum as &$node ) {
if ( is_array( $node ) && $node[PPNode_Hash_Tree::NAME] === 'possible-h' ) {
$node[PPNode_Hash_Tree::NAME] = 'h';
}
}
return [ [ 'root', $stack->rootAccum ] ];
}
private static function addLiteral( array &$accum, $text ) {
$n = count( $accum );
if ( $n && is_string( $accum[$n - 1] ) ) {
$accum[$n - 1] .= $text;
} else {
$accum[] = $text;
}
}
}