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class Parser in Lockr 7.3

Parser parses YAML strings to convert them to PHP arrays.

@author Fabien Potencier <fabien@symfony.com>

@final since version 3.4

Hierarchy

  • class \Symfony\Component\Yaml\Parser

Expanded class hierarchy of Parser

3 files declare their use of Parser
DumperTest.php in vendor/symfony/yaml/Tests/DumperTest.php
LintCommand.php in vendor/symfony/yaml/Command/LintCommand.php
ParserTest.php in vendor/symfony/yaml/Tests/ParserTest.php

File

vendor/symfony/yaml/Parser.php, line 24

Namespace

Symfony\Component\Yaml
View source
class Parser {
  const TAG_PATTERN = '(?P<tag>![\\w!.\\/:-]+)';
  const BLOCK_SCALAR_HEADER_PATTERN = '(?P<separator>\\||>)(?P<modifiers>\\+|\\-|\\d+|\\+\\d+|\\-\\d+|\\d+\\+|\\d+\\-)?(?P<comments> +#.*)?';
  private $filename;
  private $offset = 0;
  private $totalNumberOfLines;
  private $lines = [];
  private $currentLineNb = -1;
  private $currentLine = '';
  private $refs = [];
  private $skippedLineNumbers = [];
  private $locallySkippedLineNumbers = [];
  private $refsBeingParsed = [];
  public function __construct() {
    if (\func_num_args() > 0) {
      @trigger_error(sprintf('The constructor arguments $offset, $totalNumberOfLines, $skippedLineNumbers of %s are deprecated and will be removed in 4.0', self::class), E_USER_DEPRECATED);
      $this->offset = func_get_arg(0);
      if (\func_num_args() > 1) {
        $this->totalNumberOfLines = func_get_arg(1);
      }
      if (\func_num_args() > 2) {
        $this->skippedLineNumbers = func_get_arg(2);
      }
    }
  }

  /**
   * Parses a YAML file into a PHP value.
   *
   * @param string $filename The path to the YAML file to be parsed
   * @param int    $flags    A bit field of PARSE_* constants to customize the YAML parser behavior
   *
   * @return mixed The YAML converted to a PHP value
   *
   * @throws ParseException If the file could not be read or the YAML is not valid
   */
  public function parseFile($filename, $flags = 0) {
    if (!is_file($filename)) {
      throw new ParseException(sprintf('File "%s" does not exist.', $filename));
    }
    if (!is_readable($filename)) {
      throw new ParseException(sprintf('File "%s" cannot be read.', $filename));
    }
    $this->filename = $filename;
    try {
      return $this
        ->parse(file_get_contents($filename), $flags);
    } finally {
      $this->filename = null;
    }
  }

  /**
   * Parses a YAML string to a PHP value.
   *
   * @param string $value A YAML string
   * @param int    $flags A bit field of PARSE_* constants to customize the YAML parser behavior
   *
   * @return mixed A PHP value
   *
   * @throws ParseException If the YAML is not valid
   */
  public function parse($value, $flags = 0) {
    if (\is_bool($flags)) {
      @trigger_error('Passing a boolean flag to toggle exception handling is deprecated since Symfony 3.1 and will be removed in 4.0. Use the Yaml::PARSE_EXCEPTION_ON_INVALID_TYPE flag instead.', E_USER_DEPRECATED);
      if ($flags) {
        $flags = Yaml::PARSE_EXCEPTION_ON_INVALID_TYPE;
      }
      else {
        $flags = 0;
      }
    }
    if (\func_num_args() >= 3) {
      @trigger_error('Passing a boolean flag to toggle object support is deprecated since Symfony 3.1 and will be removed in 4.0. Use the Yaml::PARSE_OBJECT flag instead.', E_USER_DEPRECATED);
      if (func_get_arg(2)) {
        $flags |= Yaml::PARSE_OBJECT;
      }
    }
    if (\func_num_args() >= 4) {
      @trigger_error('Passing a boolean flag to toggle object for map support is deprecated since Symfony 3.1 and will be removed in 4.0. Use the Yaml::PARSE_OBJECT_FOR_MAP flag instead.', E_USER_DEPRECATED);
      if (func_get_arg(3)) {
        $flags |= Yaml::PARSE_OBJECT_FOR_MAP;
      }
    }
    if (Yaml::PARSE_KEYS_AS_STRINGS & $flags) {
      @trigger_error('Using the Yaml::PARSE_KEYS_AS_STRINGS flag is deprecated since Symfony 3.4 as it will be removed in 4.0. Quote your keys when they are evaluable instead.', E_USER_DEPRECATED);
    }
    if (false === preg_match('//u', $value)) {
      throw new ParseException('The YAML value does not appear to be valid UTF-8.', -1, null, $this->filename);
    }
    $this->refs = [];
    $mbEncoding = null;
    $e = null;
    $data = null;
    if (2 & (int) ini_get('mbstring.func_overload')) {
      $mbEncoding = mb_internal_encoding();
      mb_internal_encoding('UTF-8');
    }
    try {
      $data = $this
        ->doParse($value, $flags);
    } catch (\Exception $e) {
    } catch (\Throwable $e) {
    }
    if (null !== $mbEncoding) {
      mb_internal_encoding($mbEncoding);
    }
    $this->lines = [];
    $this->currentLine = '';
    $this->refs = [];
    $this->skippedLineNumbers = [];
    $this->locallySkippedLineNumbers = [];
    if (null !== $e) {
      throw $e;
    }
    return $data;
  }
  private function doParse($value, $flags) {
    $this->currentLineNb = -1;
    $this->currentLine = '';
    $value = $this
      ->cleanup($value);
    $this->lines = explode("\n", $value);
    $this->locallySkippedLineNumbers = [];
    if (null === $this->totalNumberOfLines) {
      $this->totalNumberOfLines = \count($this->lines);
    }
    if (!$this
      ->moveToNextLine()) {
      return null;
    }
    $data = [];
    $context = null;
    $allowOverwrite = false;
    while ($this
      ->isCurrentLineEmpty()) {
      if (!$this
        ->moveToNextLine()) {
        return null;
      }
    }

    // Resolves the tag and returns if end of the document
    if (null !== ($tag = $this
      ->getLineTag($this->currentLine, $flags, false)) && !$this
      ->moveToNextLine()) {
      return new TaggedValue($tag, '');
    }
    do {
      if ($this
        ->isCurrentLineEmpty()) {
        continue;
      }

      // tab?
      if ("\t" === $this->currentLine[0]) {
        throw new ParseException('A YAML file cannot contain tabs as indentation.', $this
          ->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
      }
      Inline::initialize($flags, $this
        ->getRealCurrentLineNb(), $this->filename);
      $isRef = $mergeNode = false;
      if (self::preg_match('#^\\-((?P<leadspaces>\\s+)(?P<value>.+))?$#u', rtrim($this->currentLine), $values)) {
        if ($context && 'mapping' == $context) {
          throw new ParseException('You cannot define a sequence item when in a mapping', $this
            ->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
        }
        $context = 'sequence';
        if (isset($values['value']) && self::preg_match('#^&(?P<ref>[^ ]+) *(?P<value>.*)#u', $values['value'], $matches)) {
          $isRef = $matches['ref'];
          $this->refsBeingParsed[] = $isRef;
          $values['value'] = $matches['value'];
        }
        if (isset($values['value'][1]) && '?' === $values['value'][0] && ' ' === $values['value'][1]) {
          @trigger_error($this
            ->getDeprecationMessage('Starting an unquoted string with a question mark followed by a space is deprecated since Symfony 3.3 and will throw \\Symfony\\Component\\Yaml\\Exception\\ParseException in 4.0.'), E_USER_DEPRECATED);
        }

        // array
        if (!isset($values['value']) || '' == trim($values['value'], ' ') || 0 === strpos(ltrim($values['value'], ' '), '#')) {
          $data[] = $this
            ->parseBlock($this
            ->getRealCurrentLineNb() + 1, $this
            ->getNextEmbedBlock(null, true), $flags);
        }
        elseif (null !== ($subTag = $this
          ->getLineTag(ltrim($values['value'], ' '), $flags))) {
          $data[] = new TaggedValue($subTag, $this
            ->parseBlock($this
            ->getRealCurrentLineNb() + 1, $this
            ->getNextEmbedBlock(null, true), $flags));
        }
        else {
          if (isset($values['leadspaces']) && self::preg_match('#^(?P<key>' . Inline::REGEX_QUOTED_STRING . '|[^ \'"\\{\\[].*?) *\\:(\\s+(?P<value>.+?))?\\s*$#u', $this
            ->trimTag($values['value']), $matches)) {

            // this is a compact notation element, add to next block and parse
            $block = $values['value'];
            if ($this
              ->isNextLineIndented()) {
              $block .= "\n" . $this
                ->getNextEmbedBlock($this
                ->getCurrentLineIndentation() + \strlen($values['leadspaces']) + 1);
            }
            $data[] = $this
              ->parseBlock($this
              ->getRealCurrentLineNb(), $block, $flags);
          }
          else {
            $data[] = $this
              ->parseValue($values['value'], $flags, $context);
          }
        }
        if ($isRef) {
          $this->refs[$isRef] = end($data);
          array_pop($this->refsBeingParsed);
        }
      }
      elseif (self::preg_match('#^(?P<key>(?:![^\\s]++\\s++)?(?:' . Inline::REGEX_QUOTED_STRING . '|(?:!?!php/const:)?[^ \'"\\[\\{!].*?)) *\\:(\\s++(?P<value>.+))?$#u', rtrim($this->currentLine), $values) && (false === strpos($values['key'], ' #') || \in_array($values['key'][0], [
        '"',
        "'",
      ]))) {
        if ($context && 'sequence' == $context) {
          throw new ParseException('You cannot define a mapping item when in a sequence', $this->currentLineNb + 1, $this->currentLine, $this->filename);
        }
        $context = 'mapping';
        try {
          $i = 0;
          $evaluateKey = !(Yaml::PARSE_KEYS_AS_STRINGS & $flags);

          // constants in key will be evaluated anyway
          if (isset($values['key'][0]) && '!' === $values['key'][0] && Yaml::PARSE_CONSTANT & $flags) {
            $evaluateKey = true;
          }
          $key = Inline::parseScalar($values['key'], 0, null, $i, $evaluateKey);
        } catch (ParseException $e) {
          $e
            ->setParsedLine($this
            ->getRealCurrentLineNb() + 1);
          $e
            ->setSnippet($this->currentLine);
          throw $e;
        }
        if (!\is_string($key) && !\is_int($key)) {
          $keyType = is_numeric($key) ? 'numeric key' : 'non-string key';
          @trigger_error($this
            ->getDeprecationMessage(sprintf('Implicit casting of %s to string is deprecated since Symfony 3.3 and will throw \\Symfony\\Component\\Yaml\\Exception\\ParseException in 4.0. Quote your evaluable mapping keys instead.', $keyType)), E_USER_DEPRECATED);
        }

        // Convert float keys to strings, to avoid being converted to integers by PHP
        if (\is_float($key)) {
          $key = (string) $key;
        }
        if ('<<' === $key && (!isset($values['value']) || !self::preg_match('#^&(?P<ref>[^ ]+)#u', $values['value'], $refMatches))) {
          $mergeNode = true;
          $allowOverwrite = true;
          if (isset($values['value'][0]) && '*' === $values['value'][0]) {
            $refName = substr(rtrim($values['value']), 1);
            if (!\array_key_exists($refName, $this->refs)) {
              if (false !== ($pos = array_search($refName, $this->refsBeingParsed, true))) {
                throw new ParseException(sprintf('Circular reference [%s, %s] detected for reference "%s".', implode(', ', \array_slice($this->refsBeingParsed, $pos)), $refName, $refName), $this->currentLineNb + 1, $this->currentLine, $this->filename);
              }
              throw new ParseException(sprintf('Reference "%s" does not exist.', $refName), $this
                ->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
            }
            $refValue = $this->refs[$refName];
            if (Yaml::PARSE_OBJECT_FOR_MAP & $flags && $refValue instanceof \stdClass) {
              $refValue = (array) $refValue;
            }
            if (!\is_array($refValue)) {
              throw new ParseException('YAML merge keys used with a scalar value instead of an array.', $this
                ->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
            }
            $data += $refValue;

            // array union
          }
          else {
            if (isset($values['value']) && '' !== $values['value']) {
              $value = $values['value'];
            }
            else {
              $value = $this
                ->getNextEmbedBlock();
            }
            $parsed = $this
              ->parseBlock($this
              ->getRealCurrentLineNb() + 1, $value, $flags);
            if (Yaml::PARSE_OBJECT_FOR_MAP & $flags && $parsed instanceof \stdClass) {
              $parsed = (array) $parsed;
            }
            if (!\is_array($parsed)) {
              throw new ParseException('YAML merge keys used with a scalar value instead of an array.', $this
                ->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
            }
            if (isset($parsed[0])) {

              // If the value associated with the merge key is a sequence, then this sequence is expected to contain mapping nodes
              // and each of these nodes is merged in turn according to its order in the sequence. Keys in mapping nodes earlier
              // in the sequence override keys specified in later mapping nodes.
              foreach ($parsed as $parsedItem) {
                if (Yaml::PARSE_OBJECT_FOR_MAP & $flags && $parsedItem instanceof \stdClass) {
                  $parsedItem = (array) $parsedItem;
                }
                if (!\is_array($parsedItem)) {
                  throw new ParseException('Merge items must be arrays.', $this
                    ->getRealCurrentLineNb() + 1, $parsedItem, $this->filename);
                }
                $data += $parsedItem;

                // array union
              }
            }
            else {

              // If the value associated with the key is a single mapping node, each of its key/value pairs is inserted into the
              // current mapping, unless the key already exists in it.
              $data += $parsed;

              // array union
            }
          }
        }
        elseif ('<<' !== $key && isset($values['value']) && self::preg_match('#^&(?P<ref>[^ ]++) *+(?P<value>.*)#u', $values['value'], $matches)) {
          $isRef = $matches['ref'];
          $this->refsBeingParsed[] = $isRef;
          $values['value'] = $matches['value'];
        }
        $subTag = null;
        if ($mergeNode) {

          // Merge keys
        }
        elseif (!isset($values['value']) || '' === $values['value'] || 0 === strpos($values['value'], '#') || null !== ($subTag = $this
          ->getLineTag($values['value'], $flags)) || '<<' === $key) {

          // hash
          // if next line is less indented or equal, then it means that the current value is null
          if (!$this
            ->isNextLineIndented() && !$this
            ->isNextLineUnIndentedCollection()) {

            // Spec: Keys MUST be unique; first one wins.
            // But overwriting is allowed when a merge node is used in current block.
            if ($allowOverwrite || !isset($data[$key])) {
              if (null !== $subTag) {
                $data[$key] = new TaggedValue($subTag, '');
              }
              else {
                $data[$key] = null;
              }
            }
            else {
              @trigger_error($this
                ->getDeprecationMessage(sprintf('Duplicate key "%s" detected whilst parsing YAML. Silent handling of duplicate mapping keys in YAML is deprecated since Symfony 3.2 and will throw \\Symfony\\Component\\Yaml\\Exception\\ParseException in 4.0.', $key)), E_USER_DEPRECATED);
            }
          }
          else {
            $value = $this
              ->parseBlock($this
              ->getRealCurrentLineNb() + 1, $this
              ->getNextEmbedBlock(), $flags);
            if ('<<' === $key) {
              $this->refs[$refMatches['ref']] = $value;
              if (Yaml::PARSE_OBJECT_FOR_MAP & $flags && $value instanceof \stdClass) {
                $value = (array) $value;
              }
              $data += $value;
            }
            elseif ($allowOverwrite || !isset($data[$key])) {

              // Spec: Keys MUST be unique; first one wins.
              // But overwriting is allowed when a merge node is used in current block.
              if (null !== $subTag) {
                $data[$key] = new TaggedValue($subTag, $value);
              }
              else {
                $data[$key] = $value;
              }
            }
            else {
              @trigger_error($this
                ->getDeprecationMessage(sprintf('Duplicate key "%s" detected whilst parsing YAML. Silent handling of duplicate mapping keys in YAML is deprecated since Symfony 3.2 and will throw \\Symfony\\Component\\Yaml\\Exception\\ParseException in 4.0.', $key)), E_USER_DEPRECATED);
            }
          }
        }
        else {
          $value = $this
            ->parseValue(rtrim($values['value']), $flags, $context);

          // Spec: Keys MUST be unique; first one wins.
          // But overwriting is allowed when a merge node is used in current block.
          if ($allowOverwrite || !isset($data[$key])) {
            $data[$key] = $value;
          }
          else {
            @trigger_error($this
              ->getDeprecationMessage(sprintf('Duplicate key "%s" detected whilst parsing YAML. Silent handling of duplicate mapping keys in YAML is deprecated since Symfony 3.2 and will throw \\Symfony\\Component\\Yaml\\Exception\\ParseException in 4.0.', $key)), E_USER_DEPRECATED);
          }
        }
        if ($isRef) {
          $this->refs[$isRef] = $data[$key];
          array_pop($this->refsBeingParsed);
        }
      }
      else {

        // multiple documents are not supported
        if ('---' === $this->currentLine) {
          throw new ParseException('Multiple documents are not supported.', $this->currentLineNb + 1, $this->currentLine, $this->filename);
        }
        if ($deprecatedUsage = isset($this->currentLine[1]) && '?' === $this->currentLine[0] && ' ' === $this->currentLine[1]) {
          @trigger_error($this
            ->getDeprecationMessage('Starting an unquoted string with a question mark followed by a space is deprecated since Symfony 3.3 and will throw \\Symfony\\Component\\Yaml\\Exception\\ParseException in 4.0.'), E_USER_DEPRECATED);
        }

        // 1-liner optionally followed by newline(s)
        if (\is_string($value) && $this->lines[0] === trim($value)) {
          try {
            $value = Inline::parse($this->lines[0], $flags, $this->refs);
          } catch (ParseException $e) {
            $e
              ->setParsedLine($this
              ->getRealCurrentLineNb() + 1);
            $e
              ->setSnippet($this->currentLine);
            throw $e;
          }
          return $value;
        }

        // try to parse the value as a multi-line string as a last resort
        if (0 === $this->currentLineNb) {
          $previousLineWasNewline = false;
          $previousLineWasTerminatedWithBackslash = false;
          $value = '';
          foreach ($this->lines as $line) {

            // If the indentation is not consistent at offset 0, it is to be considered as a ParseError
            if (0 === $this->offset && !$deprecatedUsage && isset($line[0]) && ' ' === $line[0]) {
              throw new ParseException('Unable to parse.', $this
                ->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
            }
            if ('' === trim($line)) {
              $value .= "\n";
            }
            elseif (!$previousLineWasNewline && !$previousLineWasTerminatedWithBackslash) {
              $value .= ' ';
            }
            if ('' !== trim($line) && '\\' === substr($line, -1)) {
              $value .= ltrim(substr($line, 0, -1));
            }
            elseif ('' !== trim($line)) {
              $value .= trim($line);
            }
            if ('' === trim($line)) {
              $previousLineWasNewline = true;
              $previousLineWasTerminatedWithBackslash = false;
            }
            elseif ('\\' === substr($line, -1)) {
              $previousLineWasNewline = false;
              $previousLineWasTerminatedWithBackslash = true;
            }
            else {
              $previousLineWasNewline = false;
              $previousLineWasTerminatedWithBackslash = false;
            }
          }
          try {
            return Inline::parse(trim($value));
          } catch (ParseException $e) {

            // fall-through to the ParseException thrown below
          }
        }
        throw new ParseException('Unable to parse.', $this
          ->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
      }
    } while ($this
      ->moveToNextLine());
    if (null !== $tag) {
      $data = new TaggedValue($tag, $data);
    }
    if (Yaml::PARSE_OBJECT_FOR_MAP & $flags && !\is_object($data) && 'mapping' === $context) {
      $object = new \stdClass();
      foreach ($data as $key => $value) {
        $object->{$key} = $value;
      }
      $data = $object;
    }
    return empty($data) ? null : $data;
  }
  private function parseBlock($offset, $yaml, $flags) {
    $skippedLineNumbers = $this->skippedLineNumbers;
    foreach ($this->locallySkippedLineNumbers as $lineNumber) {
      if ($lineNumber < $offset) {
        continue;
      }
      $skippedLineNumbers[] = $lineNumber;
    }
    $parser = new self();
    $parser->offset = $offset;
    $parser->totalNumberOfLines = $this->totalNumberOfLines;
    $parser->skippedLineNumbers = $skippedLineNumbers;
    $parser->refs =& $this->refs;
    $parser->refsBeingParsed = $this->refsBeingParsed;
    return $parser
      ->doParse($yaml, $flags);
  }

  /**
   * Returns the current line number (takes the offset into account).
   *
   * @internal
   *
   * @return int The current line number
   */
  public function getRealCurrentLineNb() {
    $realCurrentLineNumber = $this->currentLineNb + $this->offset;
    foreach ($this->skippedLineNumbers as $skippedLineNumber) {
      if ($skippedLineNumber > $realCurrentLineNumber) {
        break;
      }
      ++$realCurrentLineNumber;
    }
    return $realCurrentLineNumber;
  }

  /**
   * Returns the current line indentation.
   *
   * @return int The current line indentation
   */
  private function getCurrentLineIndentation() {
    return \strlen($this->currentLine) - \strlen(ltrim($this->currentLine, ' '));
  }

  /**
   * Returns the next embed block of YAML.
   *
   * @param int  $indentation The indent level at which the block is to be read, or null for default
   * @param bool $inSequence  True if the enclosing data structure is a sequence
   *
   * @return string A YAML string
   *
   * @throws ParseException When indentation problem are detected
   */
  private function getNextEmbedBlock($indentation = null, $inSequence = false) {
    $oldLineIndentation = $this
      ->getCurrentLineIndentation();
    if (!$this
      ->moveToNextLine()) {
      return;
    }
    if (null === $indentation) {
      $newIndent = null;
      $movements = 0;
      do {
        $EOF = false;

        // empty and comment-like lines do not influence the indentation depth
        if ($this
          ->isCurrentLineEmpty() || $this
          ->isCurrentLineComment()) {
          $EOF = !$this
            ->moveToNextLine();
          if (!$EOF) {
            ++$movements;
          }
        }
        else {
          $newIndent = $this
            ->getCurrentLineIndentation();
        }
      } while (!$EOF && null === $newIndent);
      for ($i = 0; $i < $movements; ++$i) {
        $this
          ->moveToPreviousLine();
      }
      $unindentedEmbedBlock = $this
        ->isStringUnIndentedCollectionItem();
      if (!$this
        ->isCurrentLineEmpty() && 0 === $newIndent && !$unindentedEmbedBlock) {
        throw new ParseException('Indentation problem.', $this
          ->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
      }
    }
    else {
      $newIndent = $indentation;
    }
    $data = [];
    if ($this
      ->getCurrentLineIndentation() >= $newIndent) {
      $data[] = substr($this->currentLine, $newIndent);
    }
    elseif ($this
      ->isCurrentLineEmpty() || $this
      ->isCurrentLineComment()) {
      $data[] = $this->currentLine;
    }
    else {
      $this
        ->moveToPreviousLine();
      return;
    }
    if ($inSequence && $oldLineIndentation === $newIndent && isset($data[0][0]) && '-' === $data[0][0]) {

      // the previous line contained a dash but no item content, this line is a sequence item with the same indentation
      // and therefore no nested list or mapping
      $this
        ->moveToPreviousLine();
      return;
    }
    $isItUnindentedCollection = $this
      ->isStringUnIndentedCollectionItem();
    while ($this
      ->moveToNextLine()) {
      $indent = $this
        ->getCurrentLineIndentation();
      if ($isItUnindentedCollection && !$this
        ->isCurrentLineEmpty() && !$this
        ->isStringUnIndentedCollectionItem() && $newIndent === $indent) {
        $this
          ->moveToPreviousLine();
        break;
      }
      if ($this
        ->isCurrentLineBlank()) {
        $data[] = substr($this->currentLine, $newIndent);
        continue;
      }
      if ($indent >= $newIndent) {
        $data[] = substr($this->currentLine, $newIndent);
      }
      elseif ($this
        ->isCurrentLineComment()) {
        $data[] = $this->currentLine;
      }
      elseif (0 == $indent) {
        $this
          ->moveToPreviousLine();
        break;
      }
      else {
        throw new ParseException('Indentation problem.', $this
          ->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
      }
    }
    return implode("\n", $data);
  }

  /**
   * Moves the parser to the next line.
   *
   * @return bool
   */
  private function moveToNextLine() {
    if ($this->currentLineNb >= \count($this->lines) - 1) {
      return false;
    }
    $this->currentLine = $this->lines[++$this->currentLineNb];
    return true;
  }

  /**
   * Moves the parser to the previous line.
   *
   * @return bool
   */
  private function moveToPreviousLine() {
    if ($this->currentLineNb < 1) {
      return false;
    }
    $this->currentLine = $this->lines[--$this->currentLineNb];
    return true;
  }

  /**
   * Parses a YAML value.
   *
   * @param string $value   A YAML value
   * @param int    $flags   A bit field of PARSE_* constants to customize the YAML parser behavior
   * @param string $context The parser context (either sequence or mapping)
   *
   * @return mixed A PHP value
   *
   * @throws ParseException When reference does not exist
   */
  private function parseValue($value, $flags, $context) {
    if (0 === strpos($value, '*')) {
      if (false !== ($pos = strpos($value, '#'))) {
        $value = substr($value, 1, $pos - 2);
      }
      else {
        $value = substr($value, 1);
      }
      if (!\array_key_exists($value, $this->refs)) {
        if (false !== ($pos = array_search($value, $this->refsBeingParsed, true))) {
          throw new ParseException(sprintf('Circular reference [%s, %s] detected for reference "%s".', implode(', ', \array_slice($this->refsBeingParsed, $pos)), $value, $value), $this->currentLineNb + 1, $this->currentLine, $this->filename);
        }
        throw new ParseException(sprintf('Reference "%s" does not exist.', $value), $this->currentLineNb + 1, $this->currentLine, $this->filename);
      }
      return $this->refs[$value];
    }
    if (self::preg_match('/^(?:' . self::TAG_PATTERN . ' +)?' . self::BLOCK_SCALAR_HEADER_PATTERN . '$/', $value, $matches)) {
      $modifiers = isset($matches['modifiers']) ? $matches['modifiers'] : '';
      $data = $this
        ->parseBlockScalar($matches['separator'], preg_replace('#\\d+#', '', $modifiers), (int) abs($modifiers));
      if ('' !== $matches['tag']) {
        if ('!!binary' === $matches['tag']) {
          return Inline::evaluateBinaryScalar($data);
        }
        elseif ('tagged' === $matches['tag']) {
          return new TaggedValue(substr($matches['tag'], 1), $data);
        }
        elseif ('!' !== $matches['tag']) {
          @trigger_error($this
            ->getDeprecationMessage(sprintf('Using the custom tag "%s" for the value "%s" is deprecated since Symfony 3.3. It will be replaced by an instance of %s in 4.0.', $matches['tag'], $data, TaggedValue::class)), E_USER_DEPRECATED);
        }
      }
      return $data;
    }
    try {
      $quotation = '' !== $value && ('"' === $value[0] || "'" === $value[0]) ? $value[0] : null;

      // do not take following lines into account when the current line is a quoted single line value
      if (null !== $quotation && self::preg_match('/^' . $quotation . '.*' . $quotation . '(\\s*#.*)?$/', $value)) {
        return Inline::parse($value, $flags, $this->refs);
      }
      $lines = [];
      while ($this
        ->moveToNextLine()) {

        // unquoted strings end before the first unindented line
        if (null === $quotation && 0 === $this
          ->getCurrentLineIndentation()) {
          $this
            ->moveToPreviousLine();
          break;
        }
        $lines[] = trim($this->currentLine);

        // quoted string values end with a line that is terminated with the quotation character
        if ('' !== $this->currentLine && substr($this->currentLine, -1) === $quotation) {
          break;
        }
      }
      for ($i = 0, $linesCount = \count($lines), $previousLineBlank = false; $i < $linesCount; ++$i) {
        if ('' === $lines[$i]) {
          $value .= "\n";
          $previousLineBlank = true;
        }
        elseif ($previousLineBlank) {
          $value .= $lines[$i];
          $previousLineBlank = false;
        }
        else {
          $value .= ' ' . $lines[$i];
          $previousLineBlank = false;
        }
      }
      Inline::$parsedLineNumber = $this
        ->getRealCurrentLineNb();
      $parsedValue = Inline::parse($value, $flags, $this->refs);
      if ('mapping' === $context && \is_string($parsedValue) && '"' !== $value[0] && "'" !== $value[0] && '[' !== $value[0] && '{' !== $value[0] && '!' !== $value[0] && false !== strpos($parsedValue, ': ')) {
        throw new ParseException('A colon cannot be used in an unquoted mapping value.', $this
          ->getRealCurrentLineNb() + 1, $value, $this->filename);
      }
      return $parsedValue;
    } catch (ParseException $e) {
      $e
        ->setParsedLine($this
        ->getRealCurrentLineNb() + 1);
      $e
        ->setSnippet($this->currentLine);
      throw $e;
    }
  }

  /**
   * Parses a block scalar.
   *
   * @param string $style       The style indicator that was used to begin this block scalar (| or >)
   * @param string $chomping    The chomping indicator that was used to begin this block scalar (+ or -)
   * @param int    $indentation The indentation indicator that was used to begin this block scalar
   *
   * @return string The text value
   */
  private function parseBlockScalar($style, $chomping = '', $indentation = 0) {
    $notEOF = $this
      ->moveToNextLine();
    if (!$notEOF) {
      return '';
    }
    $isCurrentLineBlank = $this
      ->isCurrentLineBlank();
    $blockLines = [];

    // leading blank lines are consumed before determining indentation
    while ($notEOF && $isCurrentLineBlank) {

      // newline only if not EOF
      if ($notEOF = $this
        ->moveToNextLine()) {
        $blockLines[] = '';
        $isCurrentLineBlank = $this
          ->isCurrentLineBlank();
      }
    }

    // determine indentation if not specified
    if (0 === $indentation) {
      if (self::preg_match('/^ +/', $this->currentLine, $matches)) {
        $indentation = \strlen($matches[0]);
      }
    }
    if ($indentation > 0) {
      $pattern = sprintf('/^ {%d}(.*)$/', $indentation);
      while ($notEOF && ($isCurrentLineBlank || self::preg_match($pattern, $this->currentLine, $matches))) {
        if ($isCurrentLineBlank && \strlen($this->currentLine) > $indentation) {
          $blockLines[] = substr($this->currentLine, $indentation);
        }
        elseif ($isCurrentLineBlank) {
          $blockLines[] = '';
        }
        else {
          $blockLines[] = $matches[1];
        }

        // newline only if not EOF
        if ($notEOF = $this
          ->moveToNextLine()) {
          $isCurrentLineBlank = $this
            ->isCurrentLineBlank();
        }
      }
    }
    elseif ($notEOF) {
      $blockLines[] = '';
    }
    if ($notEOF) {
      $blockLines[] = '';
      $this
        ->moveToPreviousLine();
    }
    elseif (!$notEOF && !$this
      ->isCurrentLineLastLineInDocument()) {
      $blockLines[] = '';
    }

    // folded style
    if ('>' === $style) {
      $text = '';
      $previousLineIndented = false;
      $previousLineBlank = false;
      for ($i = 0, $blockLinesCount = \count($blockLines); $i < $blockLinesCount; ++$i) {
        if ('' === $blockLines[$i]) {
          $text .= "\n";
          $previousLineIndented = false;
          $previousLineBlank = true;
        }
        elseif (' ' === $blockLines[$i][0]) {
          $text .= "\n" . $blockLines[$i];
          $previousLineIndented = true;
          $previousLineBlank = false;
        }
        elseif ($previousLineIndented) {
          $text .= "\n" . $blockLines[$i];
          $previousLineIndented = false;
          $previousLineBlank = false;
        }
        elseif ($previousLineBlank || 0 === $i) {
          $text .= $blockLines[$i];
          $previousLineIndented = false;
          $previousLineBlank = false;
        }
        else {
          $text .= ' ' . $blockLines[$i];
          $previousLineIndented = false;
          $previousLineBlank = false;
        }
      }
    }
    else {
      $text = implode("\n", $blockLines);
    }

    // deal with trailing newlines
    if ('' === $chomping) {
      $text = preg_replace('/\\n+$/', "\n", $text);
    }
    elseif ('-' === $chomping) {
      $text = preg_replace('/\\n+$/', '', $text);
    }
    return $text;
  }

  /**
   * Returns true if the next line is indented.
   *
   * @return bool Returns true if the next line is indented, false otherwise
   */
  private function isNextLineIndented() {
    $currentIndentation = $this
      ->getCurrentLineIndentation();
    $movements = 0;
    do {
      $EOF = !$this
        ->moveToNextLine();
      if (!$EOF) {
        ++$movements;
      }
    } while (!$EOF && ($this
      ->isCurrentLineEmpty() || $this
      ->isCurrentLineComment()));
    if ($EOF) {
      return false;
    }
    $ret = $this
      ->getCurrentLineIndentation() > $currentIndentation;
    for ($i = 0; $i < $movements; ++$i) {
      $this
        ->moveToPreviousLine();
    }
    return $ret;
  }

  /**
   * Returns true if the current line is blank or if it is a comment line.
   *
   * @return bool Returns true if the current line is empty or if it is a comment line, false otherwise
   */
  private function isCurrentLineEmpty() {
    return $this
      ->isCurrentLineBlank() || $this
      ->isCurrentLineComment();
  }

  /**
   * Returns true if the current line is blank.
   *
   * @return bool Returns true if the current line is blank, false otherwise
   */
  private function isCurrentLineBlank() {
    return '' == trim($this->currentLine, ' ');
  }

  /**
   * Returns true if the current line is a comment line.
   *
   * @return bool Returns true if the current line is a comment line, false otherwise
   */
  private function isCurrentLineComment() {

    //checking explicitly the first char of the trim is faster than loops or strpos
    $ltrimmedLine = ltrim($this->currentLine, ' ');
    return '' !== $ltrimmedLine && '#' === $ltrimmedLine[0];
  }
  private function isCurrentLineLastLineInDocument() {
    return $this->offset + $this->currentLineNb >= $this->totalNumberOfLines - 1;
  }

  /**
   * Cleanups a YAML string to be parsed.
   *
   * @param string $value The input YAML string
   *
   * @return string A cleaned up YAML string
   */
  private function cleanup($value) {
    $value = str_replace([
      "\r\n",
      "\r",
    ], "\n", $value);

    // strip YAML header
    $count = 0;
    $value = preg_replace('#^\\%YAML[: ][\\d\\.]+.*\\n#u', '', $value, -1, $count);
    $this->offset += $count;

    // remove leading comments
    $trimmedValue = preg_replace('#^(\\#.*?\\n)+#s', '', $value, -1, $count);
    if (1 === $count) {

      // items have been removed, update the offset
      $this->offset += substr_count($value, "\n") - substr_count($trimmedValue, "\n");
      $value = $trimmedValue;
    }

    // remove start of the document marker (---)
    $trimmedValue = preg_replace('#^\\-\\-\\-.*?\\n#s', '', $value, -1, $count);
    if (1 === $count) {

      // items have been removed, update the offset
      $this->offset += substr_count($value, "\n") - substr_count($trimmedValue, "\n");
      $value = $trimmedValue;

      // remove end of the document marker (...)
      $value = preg_replace('#\\.\\.\\.\\s*$#', '', $value);
    }
    return $value;
  }

  /**
   * Returns true if the next line starts unindented collection.
   *
   * @return bool Returns true if the next line starts unindented collection, false otherwise
   */
  private function isNextLineUnIndentedCollection() {
    $currentIndentation = $this
      ->getCurrentLineIndentation();
    $movements = 0;
    do {
      $EOF = !$this
        ->moveToNextLine();
      if (!$EOF) {
        ++$movements;
      }
    } while (!$EOF && ($this
      ->isCurrentLineEmpty() || $this
      ->isCurrentLineComment()));
    if ($EOF) {
      return false;
    }
    $ret = $this
      ->getCurrentLineIndentation() === $currentIndentation && $this
      ->isStringUnIndentedCollectionItem();
    for ($i = 0; $i < $movements; ++$i) {
      $this
        ->moveToPreviousLine();
    }
    return $ret;
  }

  /**
   * Returns true if the string is un-indented collection item.
   *
   * @return bool Returns true if the string is un-indented collection item, false otherwise
   */
  private function isStringUnIndentedCollectionItem() {
    return '-' === rtrim($this->currentLine) || 0 === strpos($this->currentLine, '- ');
  }

  /**
   * A local wrapper for `preg_match` which will throw a ParseException if there
   * is an internal error in the PCRE engine.
   *
   * This avoids us needing to check for "false" every time PCRE is used
   * in the YAML engine
   *
   * @throws ParseException on a PCRE internal error
   *
   * @see preg_last_error()
   *
   * @internal
   */
  public static function preg_match($pattern, $subject, &$matches = null, $flags = 0, $offset = 0) {
    if (false === ($ret = preg_match($pattern, $subject, $matches, $flags, $offset))) {
      switch (preg_last_error()) {
        case PREG_INTERNAL_ERROR:
          $error = 'Internal PCRE error.';
          break;
        case PREG_BACKTRACK_LIMIT_ERROR:
          $error = 'pcre.backtrack_limit reached.';
          break;
        case PREG_RECURSION_LIMIT_ERROR:
          $error = 'pcre.recursion_limit reached.';
          break;
        case PREG_BAD_UTF8_ERROR:
          $error = 'Malformed UTF-8 data.';
          break;
        case PREG_BAD_UTF8_OFFSET_ERROR:
          $error = 'Offset doesn\'t correspond to the begin of a valid UTF-8 code point.';
          break;
        default:
          $error = 'Error.';
      }
      throw new ParseException($error);
    }
    return $ret;
  }

  /**
   * Trim the tag on top of the value.
   *
   * Prevent values such as `!foo {quz: bar}` to be considered as
   * a mapping block.
   */
  private function trimTag($value) {
    if ('!' === $value[0]) {
      return ltrim(substr($value, 1, strcspn($value, " \r\n", 1)), ' ');
    }
    return $value;
  }
  private function getLineTag($value, $flags, $nextLineCheck = true) {
    if ('' === $value || '!' !== $value[0] || 1 !== self::preg_match('/^' . self::TAG_PATTERN . ' *( +#.*)?$/', $value, $matches)) {
      return;
    }
    if ($nextLineCheck && !$this
      ->isNextLineIndented()) {
      return;
    }
    $tag = substr($matches['tag'], 1);

    // Built-in tags
    if ($tag && '!' === $tag[0]) {
      throw new ParseException(sprintf('The built-in tag "!%s" is not implemented.', $tag), $this
        ->getRealCurrentLineNb() + 1, $value, $this->filename);
    }
    if (Yaml::PARSE_CUSTOM_TAGS & $flags) {
      return $tag;
    }
    throw new ParseException(sprintf('Tags support is not enabled. You must use the flag `Yaml::PARSE_CUSTOM_TAGS` to use "%s".', $matches['tag']), $this
      ->getRealCurrentLineNb() + 1, $value, $this->filename);
  }
  private function getDeprecationMessage($message) {
    $message = rtrim($message, '.');
    if (null !== $this->filename) {
      $message .= ' in ' . $this->filename;
    }
    $message .= ' on line ' . ($this
      ->getRealCurrentLineNb() + 1);
    return $message . '.';
  }

}

Members

Namesort descending Modifiers Type Description Overrides
Parser::$currentLine private property
Parser::$currentLineNb private property
Parser::$filename private property
Parser::$lines private property
Parser::$locallySkippedLineNumbers private property
Parser::$offset private property
Parser::$refs private property
Parser::$refsBeingParsed private property
Parser::$skippedLineNumbers private property
Parser::$totalNumberOfLines private property
Parser::BLOCK_SCALAR_HEADER_PATTERN constant
Parser::cleanup private function Cleanups a YAML string to be parsed.
Parser::doParse private function
Parser::getCurrentLineIndentation private function Returns the current line indentation.
Parser::getDeprecationMessage private function
Parser::getLineTag private function
Parser::getNextEmbedBlock private function Returns the next embed block of YAML.
Parser::getRealCurrentLineNb public function Returns the current line number (takes the offset into account).
Parser::isCurrentLineBlank private function Returns true if the current line is blank.
Parser::isCurrentLineComment private function Returns true if the current line is a comment line.
Parser::isCurrentLineEmpty private function Returns true if the current line is blank or if it is a comment line.
Parser::isCurrentLineLastLineInDocument private function
Parser::isNextLineIndented private function Returns true if the next line is indented.
Parser::isNextLineUnIndentedCollection private function Returns true if the next line starts unindented collection.
Parser::isStringUnIndentedCollectionItem private function Returns true if the string is un-indented collection item.
Parser::moveToNextLine private function Moves the parser to the next line.
Parser::moveToPreviousLine private function Moves the parser to the previous line.
Parser::parse public function Parses a YAML string to a PHP value.
Parser::parseBlock private function
Parser::parseBlockScalar private function Parses a block scalar.
Parser::parseFile public function Parses a YAML file into a PHP value.
Parser::parseValue private function Parses a YAML value.
Parser::preg_match public static function A local wrapper for `preg_match` which will throw a ParseException if there is an internal error in the PCRE engine.
Parser::TAG_PATTERN constant
Parser::trimTag private function Trim the tag on top of the value.
Parser::__construct public function