gluon-web-remote

Web remote Administration for big size of gluon routers
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Parser.php (27412B)


      1 <?php
      2 
      3 /*
      4  * This file is part of the Symfony package.
      5  *
      6  * (c) Fabien Potencier <fabien@symfony.com>
      7  *
      8  * For the full copyright and license information, please view the LICENSE
      9  * file that was distributed with this source code.
     10  */
     11 
     12 namespace Symfony\Component\Yaml;
     13 
     14 use Symfony\Component\Yaml\Exception\ParseException;
     15 
     16 /**
     17  * Parser parses YAML strings to convert them to PHP arrays.
     18  *
     19  * @author Fabien Potencier <fabien@symfony.com>
     20  */
     21 class Parser
     22 {
     23     const BLOCK_SCALAR_HEADER_PATTERN = '(?P<separator>\||>)(?P<modifiers>\+|\-|\d+|\+\d+|\-\d+|\d+\+|\d+\-)?(?P<comments> +#.*)?';
     24     // BC - wrongly named
     25     const FOLDED_SCALAR_PATTERN = self::BLOCK_SCALAR_HEADER_PATTERN;
     26 
     27     private $offset = 0;
     28     private $lines = array();
     29     private $currentLineNb = -1;
     30     private $currentLine = '';
     31     private $refs = array();
     32 
     33     /**
     34      * Constructor.
     35      *
     36      * @param int $offset The offset of YAML document (used for line numbers in error messages)
     37      */
     38     public function __construct($offset = 0)
     39     {
     40         $this->offset = $offset;
     41     }
     42 
     43     /**
     44      * Parses a YAML string to a PHP value.
     45      *
     46      * @param string $value                  A YAML string
     47      * @param bool   $exceptionOnInvalidType true if an exception must be thrown on invalid types (a PHP resource or object), false otherwise
     48      * @param bool   $objectSupport          true if object support is enabled, false otherwise
     49      * @param bool   $objectForMap           true if maps should return a stdClass instead of array()
     50      *
     51      * @return mixed A PHP value
     52      *
     53      * @throws ParseException If the YAML is not valid
     54      */
     55     public function parse($value, $exceptionOnInvalidType = false, $objectSupport = false, $objectForMap = false)
     56     {
     57         if (!preg_match('//u', $value)) {
     58             throw new ParseException('The YAML value does not appear to be valid UTF-8.');
     59         }
     60         $this->currentLineNb = -1;
     61         $this->currentLine = '';
     62         $value = $this->cleanup($value);
     63         $this->lines = explode("\n", $value);
     64 
     65         if (function_exists('mb_internal_encoding') && ((int) ini_get('mbstring.func_overload')) & 2) {
     66             $mbEncoding = mb_internal_encoding();
     67             mb_internal_encoding('UTF-8');
     68         }
     69 
     70         $data = array();
     71         $context = null;
     72         $allowOverwrite = false;
     73         while ($this->moveToNextLine()) {
     74             if ($this->isCurrentLineEmpty()) {
     75                 continue;
     76             }
     77 
     78             // tab?
     79             if ("\t" === $this->currentLine[0]) {
     80                 throw new ParseException('A YAML file cannot contain tabs as indentation.', $this->getRealCurrentLineNb() + 1, $this->currentLine);
     81             }
     82 
     83             $isRef = $mergeNode = false;
     84             if (preg_match('#^\-((?P<leadspaces>\s+)(?P<value>.+?))?\s*$#u', $this->currentLine, $values)) {
     85                 if ($context && 'mapping' == $context) {
     86                     throw new ParseException('You cannot define a sequence item when in a mapping');
     87                 }
     88                 $context = 'sequence';
     89 
     90                 if (isset($values['value']) && preg_match('#^&(?P<ref>[^ ]+) *(?P<value>.*)#u', $values['value'], $matches)) {
     91                     $isRef = $matches['ref'];
     92                     $values['value'] = $matches['value'];
     93                 }
     94 
     95                 // array
     96                 if (!isset($values['value']) || '' == trim($values['value'], ' ') || 0 === strpos(ltrim($values['value'], ' '), '#')) {
     97                     $c = $this->getRealCurrentLineNb() + 1;
     98                     $parser = new self($c);
     99                     $parser->refs = &$this->refs;
    100                     $data[] = $parser->parse($this->getNextEmbedBlock(null, true), $exceptionOnInvalidType, $objectSupport, $objectForMap);
    101                 } else {
    102                     if (isset($values['leadspaces'])
    103                         && preg_match('#^(?P<key>'.Inline::REGEX_QUOTED_STRING.'|[^ \'"\{\[].*?) *\:(\s+(?P<value>.+?))?\s*$#u', $values['value'], $matches)
    104                     ) {
    105                         // this is a compact notation element, add to next block and parse
    106                         $c = $this->getRealCurrentLineNb();
    107                         $parser = new self($c);
    108                         $parser->refs = &$this->refs;
    109 
    110                         $block = $values['value'];
    111                         if ($this->isNextLineIndented()) {
    112                             $block .= "\n".$this->getNextEmbedBlock($this->getCurrentLineIndentation() + strlen($values['leadspaces']) + 1);
    113                         }
    114 
    115                         $data[] = $parser->parse($block, $exceptionOnInvalidType, $objectSupport, $objectForMap);
    116                     } else {
    117                         $data[] = $this->parseValue($values['value'], $exceptionOnInvalidType, $objectSupport, $objectForMap);
    118                     }
    119                 }
    120                 if ($isRef) {
    121                     $this->refs[$isRef] = end($data);
    122                 }
    123             } elseif (preg_match('#^(?P<key>'.Inline::REGEX_QUOTED_STRING.'|[^ \'"\[\{].*?) *\:(\s+(?P<value>.+?))?\s*$#u', $this->currentLine, $values) && (false === strpos($values['key'], ' #') || in_array($values['key'][0], array('"', "'")))) {
    124                 if ($context && 'sequence' == $context) {
    125                     throw new ParseException('You cannot define a mapping item when in a sequence');
    126                 }
    127                 $context = 'mapping';
    128 
    129                 // force correct settings
    130                 Inline::parse(null, $exceptionOnInvalidType, $objectSupport, $objectForMap, $this->refs);
    131                 try {
    132                     $key = Inline::parseScalar($values['key']);
    133                 } catch (ParseException $e) {
    134                     $e->setParsedLine($this->getRealCurrentLineNb() + 1);
    135                     $e->setSnippet($this->currentLine);
    136 
    137                     throw $e;
    138                 }
    139 
    140                 // Convert float keys to strings, to avoid being converted to integers by PHP
    141                 if (is_float($key)) {
    142                     $key = (string) $key;
    143                 }
    144 
    145                 if ('<<' === $key) {
    146                     $mergeNode = true;
    147                     $allowOverwrite = true;
    148                     if (isset($values['value']) && 0 === strpos($values['value'], '*')) {
    149                         $refName = substr($values['value'], 1);
    150                         if (!array_key_exists($refName, $this->refs)) {
    151                             throw new ParseException(sprintf('Reference "%s" does not exist.', $refName), $this->getRealCurrentLineNb() + 1, $this->currentLine);
    152                         }
    153 
    154                         $refValue = $this->refs[$refName];
    155 
    156                         if (!is_array($refValue)) {
    157                             throw new ParseException('YAML merge keys used with a scalar value instead of an array.', $this->getRealCurrentLineNb() + 1, $this->currentLine);
    158                         }
    159 
    160                         foreach ($refValue as $key => $value) {
    161                             if (!isset($data[$key])) {
    162                                 $data[$key] = $value;
    163                             }
    164                         }
    165                     } else {
    166                         if (isset($values['value']) && $values['value'] !== '') {
    167                             $value = $values['value'];
    168                         } else {
    169                             $value = $this->getNextEmbedBlock();
    170                         }
    171                         $c = $this->getRealCurrentLineNb() + 1;
    172                         $parser = new self($c);
    173                         $parser->refs = &$this->refs;
    174                         $parsed = $parser->parse($value, $exceptionOnInvalidType, $objectSupport, $objectForMap);
    175 
    176                         if (!is_array($parsed)) {
    177                             throw new ParseException('YAML merge keys used with a scalar value instead of an array.', $this->getRealCurrentLineNb() + 1, $this->currentLine);
    178                         }
    179 
    180                         if (isset($parsed[0])) {
    181                             // If the value associated with the merge key is a sequence, then this sequence is expected to contain mapping nodes
    182                             // and each of these nodes is merged in turn according to its order in the sequence. Keys in mapping nodes earlier
    183                             // in the sequence override keys specified in later mapping nodes.
    184                             foreach ($parsed as $parsedItem) {
    185                                 if (!is_array($parsedItem)) {
    186                                     throw new ParseException('Merge items must be arrays.', $this->getRealCurrentLineNb() + 1, $parsedItem);
    187                                 }
    188 
    189                                 foreach ($parsedItem as $key => $value) {
    190                                     if (!isset($data[$key])) {
    191                                         $data[$key] = $value;
    192                                     }
    193                                 }
    194                             }
    195                         } else {
    196                             // If the value associated with the key is a single mapping node, each of its key/value pairs is inserted into the
    197                             // current mapping, unless the key already exists in it.
    198                             foreach ($parsed as $key => $value) {
    199                                 if (!isset($data[$key])) {
    200                                     $data[$key] = $value;
    201                                 }
    202                             }
    203                         }
    204                     }
    205                 } elseif (isset($values['value']) && preg_match('#^&(?P<ref>[^ ]+) *(?P<value>.*)#u', $values['value'], $matches)) {
    206                     $isRef = $matches['ref'];
    207                     $values['value'] = $matches['value'];
    208                 }
    209 
    210                 if ($mergeNode) {
    211                     // Merge keys
    212                 } elseif (!isset($values['value']) || '' == trim($values['value'], ' ') || 0 === strpos(ltrim($values['value'], ' '), '#')) {
    213                     // hash
    214                     // if next line is less indented or equal, then it means that the current value is null
    215                     if (!$this->isNextLineIndented() && !$this->isNextLineUnIndentedCollection()) {
    216                         // Spec: Keys MUST be unique; first one wins.
    217                         // But overwriting is allowed when a merge node is used in current block.
    218                         if ($allowOverwrite || !isset($data[$key])) {
    219                             $data[$key] = null;
    220                         }
    221                     } else {
    222                         $c = $this->getRealCurrentLineNb() + 1;
    223                         $parser = new self($c);
    224                         $parser->refs = &$this->refs;
    225                         $value = $parser->parse($this->getNextEmbedBlock(), $exceptionOnInvalidType, $objectSupport, $objectForMap);
    226                         // Spec: Keys MUST be unique; first one wins.
    227                         // But overwriting is allowed when a merge node is used in current block.
    228                         if ($allowOverwrite || !isset($data[$key])) {
    229                             $data[$key] = $value;
    230                         }
    231                     }
    232                 } else {
    233                     $value = $this->parseValue($values['value'], $exceptionOnInvalidType, $objectSupport, $objectForMap);
    234                     // Spec: Keys MUST be unique; first one wins.
    235                     // But overwriting is allowed when a merge node is used in current block.
    236                     if ($allowOverwrite || !isset($data[$key])) {
    237                         $data[$key] = $value;
    238                     }
    239                 }
    240                 if ($isRef) {
    241                     $this->refs[$isRef] = $data[$key];
    242                 }
    243             } else {
    244                 // multiple documents are not supported
    245                 if ('---' === $this->currentLine) {
    246                     throw new ParseException('Multiple documents are not supported.');
    247                 }
    248 
    249                 // 1-liner optionally followed by newline(s)
    250                 if (is_string($value) && $this->lines[0] === trim($value)) {
    251                     try {
    252                         $value = Inline::parse($this->lines[0], $exceptionOnInvalidType, $objectSupport, $objectForMap, $this->refs);
    253                     } catch (ParseException $e) {
    254                         $e->setParsedLine($this->getRealCurrentLineNb() + 1);
    255                         $e->setSnippet($this->currentLine);
    256 
    257                         throw $e;
    258                     }
    259 
    260                     if (is_array($value)) {
    261                         $first = reset($value);
    262                         if (is_string($first) && 0 === strpos($first, '*')) {
    263                             $data = array();
    264                             foreach ($value as $alias) {
    265                                 $data[] = $this->refs[substr($alias, 1)];
    266                             }
    267                             $value = $data;
    268                         }
    269                     }
    270 
    271                     if (isset($mbEncoding)) {
    272                         mb_internal_encoding($mbEncoding);
    273                     }
    274 
    275                     return $value;
    276                 }
    277 
    278                 switch (preg_last_error()) {
    279                     case PREG_INTERNAL_ERROR:
    280                         $error = 'Internal PCRE error.';
    281                         break;
    282                     case PREG_BACKTRACK_LIMIT_ERROR:
    283                         $error = 'pcre.backtrack_limit reached.';
    284                         break;
    285                     case PREG_RECURSION_LIMIT_ERROR:
    286                         $error = 'pcre.recursion_limit reached.';
    287                         break;
    288                     case PREG_BAD_UTF8_ERROR:
    289                         $error = 'Malformed UTF-8 data.';
    290                         break;
    291                     case PREG_BAD_UTF8_OFFSET_ERROR:
    292                         $error = 'Offset doesn\'t correspond to the begin of a valid UTF-8 code point.';
    293                         break;
    294                     default:
    295                         $error = 'Unable to parse.';
    296                 }
    297 
    298                 throw new ParseException($error, $this->getRealCurrentLineNb() + 1, $this->currentLine);
    299             }
    300         }
    301 
    302         if (isset($mbEncoding)) {
    303             mb_internal_encoding($mbEncoding);
    304         }
    305 
    306         return empty($data) ? null : $data;
    307     }
    308 
    309     /**
    310      * Returns the current line number (takes the offset into account).
    311      *
    312      * @return int The current line number
    313      */
    314     private function getRealCurrentLineNb()
    315     {
    316         return $this->currentLineNb + $this->offset;
    317     }
    318 
    319     /**
    320      * Returns the current line indentation.
    321      *
    322      * @return int The current line indentation
    323      */
    324     private function getCurrentLineIndentation()
    325     {
    326         return strlen($this->currentLine) - strlen(ltrim($this->currentLine, ' '));
    327     }
    328 
    329     /**
    330      * Returns the next embed block of YAML.
    331      *
    332      * @param int  $indentation The indent level at which the block is to be read, or null for default
    333      * @param bool $inSequence  True if the enclosing data structure is a sequence
    334      *
    335      * @return string A YAML string
    336      *
    337      * @throws ParseException When indentation problem are detected
    338      */
    339     private function getNextEmbedBlock($indentation = null, $inSequence = false)
    340     {
    341         $oldLineIndentation = $this->getCurrentLineIndentation();
    342 
    343         if (!$this->moveToNextLine()) {
    344             return;
    345         }
    346 
    347         if (null === $indentation) {
    348             $newIndent = $this->getCurrentLineIndentation();
    349 
    350             $unindentedEmbedBlock = $this->isStringUnIndentedCollectionItem($this->currentLine);
    351 
    352             if (!$this->isCurrentLineEmpty() && 0 === $newIndent && !$unindentedEmbedBlock) {
    353                 throw new ParseException('Indentation problem.', $this->getRealCurrentLineNb() + 1, $this->currentLine);
    354             }
    355         } else {
    356             $newIndent = $indentation;
    357         }
    358 
    359         $data = array();
    360         if ($this->getCurrentLineIndentation() >= $newIndent) {
    361             $data[] = substr($this->currentLine, $newIndent);
    362         } else {
    363             $this->moveToPreviousLine();
    364 
    365             return;
    366         }
    367 
    368         if ($inSequence && $oldLineIndentation === $newIndent && isset($data[0][0]) && '-' === $data[0][0]) {
    369             // the previous line contained a dash but no item content, this line is a sequence item with the same indentation
    370             // and therefore no nested list or mapping
    371             $this->moveToPreviousLine();
    372 
    373             return;
    374         }
    375 
    376         $isItUnindentedCollection = $this->isStringUnIndentedCollectionItem($this->currentLine);
    377 
    378         // Comments must not be removed inside a block scalar
    379         $removeCommentsPattern = '~'.self::BLOCK_SCALAR_HEADER_PATTERN.'$~';
    380         $removeComments = !preg_match($removeCommentsPattern, $this->currentLine);
    381 
    382         while ($this->moveToNextLine()) {
    383             $indent = $this->getCurrentLineIndentation();
    384 
    385             if ($indent === $newIndent) {
    386                 $removeComments = !preg_match($removeCommentsPattern, $this->currentLine);
    387             }
    388 
    389             if ($isItUnindentedCollection && !$this->isStringUnIndentedCollectionItem($this->currentLine) && $newIndent === $indent) {
    390                 $this->moveToPreviousLine();
    391                 break;
    392             }
    393 
    394             if ($this->isCurrentLineBlank()) {
    395                 $data[] = substr($this->currentLine, $newIndent);
    396                 continue;
    397             }
    398 
    399             if ($removeComments && $this->isCurrentLineComment()) {
    400                 continue;
    401             }
    402 
    403             if ($indent >= $newIndent) {
    404                 $data[] = substr($this->currentLine, $newIndent);
    405             } elseif (0 == $indent) {
    406                 $this->moveToPreviousLine();
    407 
    408                 break;
    409             } else {
    410                 throw new ParseException('Indentation problem.', $this->getRealCurrentLineNb() + 1, $this->currentLine);
    411             }
    412         }
    413 
    414         return implode("\n", $data);
    415     }
    416 
    417     /**
    418      * Moves the parser to the next line.
    419      *
    420      * @return bool
    421      */
    422     private function moveToNextLine()
    423     {
    424         if ($this->currentLineNb >= count($this->lines) - 1) {
    425             return false;
    426         }
    427 
    428         $this->currentLine = $this->lines[++$this->currentLineNb];
    429 
    430         return true;
    431     }
    432 
    433     /**
    434      * Moves the parser to the previous line.
    435      */
    436     private function moveToPreviousLine()
    437     {
    438         $this->currentLine = $this->lines[--$this->currentLineNb];
    439     }
    440 
    441     /**
    442      * Parses a YAML value.
    443      *
    444      * @param string $value                  A YAML value
    445      * @param bool   $exceptionOnInvalidType True if an exception must be thrown on invalid types false otherwise
    446      * @param bool   $objectSupport          True if object support is enabled, false otherwise
    447      * @param bool   $objectForMap           true if maps should return a stdClass instead of array()
    448      *
    449      * @return mixed A PHP value
    450      *
    451      * @throws ParseException When reference does not exist
    452      */
    453     private function parseValue($value, $exceptionOnInvalidType, $objectSupport, $objectForMap)
    454     {
    455         if (0 === strpos($value, '*')) {
    456             if (false !== $pos = strpos($value, '#')) {
    457                 $value = substr($value, 1, $pos - 2);
    458             } else {
    459                 $value = substr($value, 1);
    460             }
    461 
    462             if (!array_key_exists($value, $this->refs)) {
    463                 throw new ParseException(sprintf('Reference "%s" does not exist.', $value), $this->currentLine);
    464             }
    465 
    466             return $this->refs[$value];
    467         }
    468 
    469         if (preg_match('/^'.self::BLOCK_SCALAR_HEADER_PATTERN.'$/', $value, $matches)) {
    470             $modifiers = isset($matches['modifiers']) ? $matches['modifiers'] : '';
    471 
    472             return $this->parseBlockScalar($matches['separator'], preg_replace('#\d+#', '', $modifiers), (int) abs($modifiers));
    473         }
    474 
    475         try {
    476             return Inline::parse($value, $exceptionOnInvalidType, $objectSupport, $objectForMap, $this->refs);
    477         } catch (ParseException $e) {
    478             $e->setParsedLine($this->getRealCurrentLineNb() + 1);
    479             $e->setSnippet($this->currentLine);
    480 
    481             throw $e;
    482         }
    483     }
    484 
    485     /**
    486      * Parses a block scalar.
    487      *
    488      * @param string $style       The style indicator that was used to begin this block scalar (| or >)
    489      * @param string $chomping    The chomping indicator that was used to begin this block scalar (+ or -)
    490      * @param int    $indentation The indentation indicator that was used to begin this block scalar
    491      *
    492      * @return string The text value
    493      */
    494     private function parseBlockScalar($style, $chomping = '', $indentation = 0)
    495     {
    496         $notEOF = $this->moveToNextLine();
    497         if (!$notEOF) {
    498             return '';
    499         }
    500 
    501         $isCurrentLineBlank = $this->isCurrentLineBlank();
    502         $text = '';
    503 
    504         // leading blank lines are consumed before determining indentation
    505         while ($notEOF && $isCurrentLineBlank) {
    506             // newline only if not EOF
    507             if ($notEOF = $this->moveToNextLine()) {
    508                 $text .= "\n";
    509                 $isCurrentLineBlank = $this->isCurrentLineBlank();
    510             }
    511         }
    512 
    513         // determine indentation if not specified
    514         if (0 === $indentation) {
    515             if (preg_match('/^ +/', $this->currentLine, $matches)) {
    516                 $indentation = strlen($matches[0]);
    517             }
    518         }
    519 
    520         if ($indentation > 0) {
    521             $pattern = sprintf('/^ {%d}(.*)$/', $indentation);
    522 
    523             while (
    524                 $notEOF && (
    525                     $isCurrentLineBlank ||
    526                     preg_match($pattern, $this->currentLine, $matches)
    527                 )
    528             ) {
    529                 if ($isCurrentLineBlank) {
    530                     $text .= substr($this->currentLine, $indentation);
    531                 } else {
    532                     $text .= $matches[1];
    533                 }
    534 
    535                 // newline only if not EOF
    536                 if ($notEOF = $this->moveToNextLine()) {
    537                     $text .= "\n";
    538                     $isCurrentLineBlank = $this->isCurrentLineBlank();
    539                 }
    540             }
    541         } elseif ($notEOF) {
    542             $text .= "\n";
    543         }
    544 
    545         if ($notEOF) {
    546             $this->moveToPreviousLine();
    547         }
    548 
    549         // folded style
    550         if ('>' === $style) {
    551             // folded lines
    552             // replace all non-leading/non-trailing single newlines with spaces
    553             preg_match('/(\n*)$/', $text, $matches);
    554             $text = preg_replace('/(?<!\n|^)\n(?!\n)/', ' ', rtrim($text, "\n"));
    555             $text .= $matches[1];
    556 
    557             // empty separation lines
    558             // remove one newline from each group of non-leading/non-trailing newlines
    559             $text = preg_replace('/[^\n]\n+\K\n(?=[^\n])/', '', $text);
    560         }
    561 
    562         // deal with trailing newlines
    563         if ('' === $chomping) {
    564             $text = preg_replace('/\n+$/', "\n", $text);
    565         } elseif ('-' === $chomping) {
    566             $text = preg_replace('/\n+$/', '', $text);
    567         }
    568 
    569         return $text;
    570     }
    571 
    572     /**
    573      * Returns true if the next line is indented.
    574      *
    575      * @return bool Returns true if the next line is indented, false otherwise
    576      */
    577     private function isNextLineIndented()
    578     {
    579         $currentIndentation = $this->getCurrentLineIndentation();
    580         $EOF = !$this->moveToNextLine();
    581 
    582         while (!$EOF && $this->isCurrentLineEmpty()) {
    583             $EOF = !$this->moveToNextLine();
    584         }
    585 
    586         if ($EOF) {
    587             return false;
    588         }
    589 
    590         $ret = false;
    591         if ($this->getCurrentLineIndentation() > $currentIndentation) {
    592             $ret = true;
    593         }
    594 
    595         $this->moveToPreviousLine();
    596 
    597         return $ret;
    598     }
    599 
    600     /**
    601      * Returns true if the current line is blank or if it is a comment line.
    602      *
    603      * @return bool Returns true if the current line is empty or if it is a comment line, false otherwise
    604      */
    605     private function isCurrentLineEmpty()
    606     {
    607         return $this->isCurrentLineBlank() || $this->isCurrentLineComment();
    608     }
    609 
    610     /**
    611      * Returns true if the current line is blank.
    612      *
    613      * @return bool Returns true if the current line is blank, false otherwise
    614      */
    615     private function isCurrentLineBlank()
    616     {
    617         return '' == trim($this->currentLine, ' ');
    618     }
    619 
    620     /**
    621      * Returns true if the current line is a comment line.
    622      *
    623      * @return bool Returns true if the current line is a comment line, false otherwise
    624      */
    625     private function isCurrentLineComment()
    626     {
    627         //checking explicitly the first char of the trim is faster than loops or strpos
    628         $ltrimmedLine = ltrim($this->currentLine, ' ');
    629 
    630         return $ltrimmedLine[0] === '#';
    631     }
    632 
    633     /**
    634      * Cleanups a YAML string to be parsed.
    635      *
    636      * @param string $value The input YAML string
    637      *
    638      * @return string A cleaned up YAML string
    639      */
    640     private function cleanup($value)
    641     {
    642         $value = str_replace(array("\r\n", "\r"), "\n", $value);
    643 
    644         // strip YAML header
    645         $count = 0;
    646         $value = preg_replace('#^\%YAML[: ][\d\.]+.*\n#u', '', $value, -1, $count);
    647         $this->offset += $count;
    648 
    649         // remove leading comments
    650         $trimmedValue = preg_replace('#^(\#.*?\n)+#s', '', $value, -1, $count);
    651         if ($count == 1) {
    652             // items have been removed, update the offset
    653             $this->offset += substr_count($value, "\n") - substr_count($trimmedValue, "\n");
    654             $value = $trimmedValue;
    655         }
    656 
    657         // remove start of the document marker (---)
    658         $trimmedValue = preg_replace('#^\-\-\-.*?\n#s', '', $value, -1, $count);
    659         if ($count == 1) {
    660             // items have been removed, update the offset
    661             $this->offset += substr_count($value, "\n") - substr_count($trimmedValue, "\n");
    662             $value = $trimmedValue;
    663 
    664             // remove end of the document marker (...)
    665             $value = preg_replace('#\.\.\.\s*$#', '', $value);
    666         }
    667 
    668         return $value;
    669     }
    670 
    671     /**
    672      * Returns true if the next line starts unindented collection.
    673      *
    674      * @return bool Returns true if the next line starts unindented collection, false otherwise
    675      */
    676     private function isNextLineUnIndentedCollection()
    677     {
    678         $currentIndentation = $this->getCurrentLineIndentation();
    679         $notEOF = $this->moveToNextLine();
    680 
    681         while ($notEOF && $this->isCurrentLineEmpty()) {
    682             $notEOF = $this->moveToNextLine();
    683         }
    684 
    685         if (false === $notEOF) {
    686             return false;
    687         }
    688 
    689         $ret = false;
    690         if (
    691             $this->getCurrentLineIndentation() == $currentIndentation
    692             &&
    693             $this->isStringUnIndentedCollectionItem($this->currentLine)
    694         ) {
    695             $ret = true;
    696         }
    697 
    698         $this->moveToPreviousLine();
    699 
    700         return $ret;
    701     }
    702 
    703     /**
    704      * Returns true if the string is un-indented collection item.
    705      *
    706      * @return bool Returns true if the string is un-indented collection item, false otherwise
    707      */
    708     private function isStringUnIndentedCollectionItem()
    709     {
    710         return (0 === strpos($this->currentLine, '- '));
    711     }
    712 }