vendor/twig/twig/src/Lexer.php line 430

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  1. <?php
  3. /*
  4.  * This file is part of Twig.
  5.  *
  6.  * (c) Fabien Potencier
  7.  * (c) Armin Ronacher
  8.  *
  9.  * For the full copyright and license information, please view the LICENSE
  10.  * file that was distributed with this source code.
  11.  */
  13. namespace Twig;
  15. use Twig\Error\SyntaxError;
  17. /**
  18.  * @author Fabien Potencier <fabien@symfony.com>
  19.  */
  20. class Lexer
  21. {
  22.     private $isInitialized = false;
  24.     private $tokens;
  25.     private $code;
  26.     private $cursor;
  27.     private $lineno;
  28.     private $end;
  29.     private $state;
  30.     private $states;
  31.     private $brackets;
  32.     private $env;
  33.     private $source;
  34.     private $options;
  35.     private $regexes;
  36.     private $position;
  37.     private $positions;
  38.     private $currentVarBlockLine;
  39.     private array $openingBrackets = ['{', '(', '['];
  40.     private array $closingBrackets = ['}', ')', ']'];
  42.     public const STATE_DATA = 0;
  43.     public const STATE_BLOCK = 1;
  44.     public const STATE_VAR = 2;
  45.     public const STATE_STRING = 3;
  46.     public const STATE_INTERPOLATION = 4;
  48.     public const REGEX_NAME = '/[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*/A';
  49.     public const REGEX_STRING = '/"([^#"\\\\]*(?:\\\\.[^#"\\\\]*)*)"|\'([^\'\\\\]*(?:\\\\.[^\'\\\\]*)*)\'/As';
  51.     public const REGEX_NUMBER = '/(?(DEFINE)
  52.         (?<LNUM>[0-9]+(_[0-9]+)*)               # Integers (with underscores)   123_456
  53.         (?<FRAC>\.(?&LNUM))                     # Fractional part               .456
  54.         (?<EXPONENT>[eE][+-]?(?&LNUM))          # Exponent part                 E+10
  55.         (?<DNUM>(?&LNUM)(?:(?&FRAC))?)          # Decimal number                123_456.456
  56.     )(?:(?&DNUM)(?:(?&EXPONENT))?)              #                               123_456.456E+10
  57.     /Ax';
  59.     public const REGEX_DQ_STRING_DELIM = '/"/A';
  60.     public const REGEX_DQ_STRING_PART = '/[^#"\\\\]*(?:(?:\\\\.|#(?!\{))[^#"\\\\]*)*/As';
  61.     public const REGEX_INLINE_COMMENT = '/#[^\n]*/A';
  62.     public const PUNCTUATION = '()[]{}?:.,|';
  64.     private const SPECIAL_CHARS = [
  65.         'f' => "\f",
  66.         'n' => "\n",
  67.         'r' => "\r",
  68.         't' => "\t",
  69.         'v' => "\v",
  70.     ];
  72.     public function __construct(Environment $env, array $options = [])
  73.     {
  74.         $this->env = $env;
  76.         $this->options = array_merge([
  77.             'tag_comment' => ['{#', '#}'],
  78.             'tag_block' => ['{%', '%}'],
  79.             'tag_variable' => ['{{', '}}'],
  80.             'whitespace_trim' => '-',
  81.             'whitespace_line_trim' => '~',
  82.             'whitespace_line_chars' => ' \t\0\x0B',
  83.             'interpolation' => ['#{', '}'],
  84.         ], $options);
  85.     }
  87.     private function initialize(): void
  88.     {
  89.         if ($this->isInitialized) {
  90.             return;
  91.         }
  93.         // when PHP 7.3 is the min version, we will be able to remove the '#' part in preg_quote as it's part of the default
  94.         $this->regexes = [
  95.             // }}
  96.             'lex_var' => '{
  97.                 \s*
  98.                 (?:'.
  99.                     preg_quote($this->options['whitespace_trim'].$this->options['tag_variable'][1], '#').'\s*'. // -}}\s*
  100.                     '|'.
  101.                     preg_quote($this->options['whitespace_line_trim'].$this->options['tag_variable'][1], '#').'['.$this->options['whitespace_line_chars'].']*'. // ~}}[ \t\0\x0B]*
  102.                     '|'.
  103.                     preg_quote($this->options['tag_variable'][1], '#'). // }}
  104.                 ')
  105.             }Ax',
  107.             // %}
  108.             'lex_block' => '{
  109.                 \s*
  110.                 (?:'.
  111.                     preg_quote($this->options['whitespace_trim'].$this->options['tag_block'][1], '#').'\s*\n?'. // -%}\s*\n?
  112.                     '|'.
  113.                     preg_quote($this->options['whitespace_line_trim'].$this->options['tag_block'][1], '#').'['.$this->options['whitespace_line_chars'].']*'. // ~%}[ \t\0\x0B]*
  114.                     '|'.
  115.                     preg_quote($this->options['tag_block'][1], '#').'\n?'. // %}\n?
  116.                 ')
  117.             }Ax',
  119.             // {% endverbatim %}
  120.             'lex_raw_data' => '{'.
  121.                 preg_quote($this->options['tag_block'][0], '#'). // {%
  122.                 '('.
  123.                     $this->options['whitespace_trim']. // -
  124.                     '|'.
  125.                     $this->options['whitespace_line_trim']. // ~
  126.                 ')?\s*endverbatim\s*'.
  127.                 '(?:'.
  128.                     preg_quote($this->options['whitespace_trim'].$this->options['tag_block'][1], '#').'\s*'. // -%}
  129.                     '|'.
  130.                     preg_quote($this->options['whitespace_line_trim'].$this->options['tag_block'][1], '#').'['.$this->options['whitespace_line_chars'].']*'. // ~%}[ \t\0\x0B]*
  131.                     '|'.
  132.                     preg_quote($this->options['tag_block'][1], '#'). // %}
  133.                 ')
  134.             }sx',
  136.             'operator' => $this->getOperatorRegex(),
  138.             // #}
  139.             'lex_comment' => '{
  140.                 (?:'.
  141.                     preg_quote($this->options['whitespace_trim'].$this->options['tag_comment'][1], '#').'\s*\n?'. // -#}\s*\n?
  142.                     '|'.
  143.                     preg_quote($this->options['whitespace_line_trim'].$this->options['tag_comment'][1], '#').'['.$this->options['whitespace_line_chars'].']*'. // ~#}[ \t\0\x0B]*
  144.                     '|'.
  145.                     preg_quote($this->options['tag_comment'][1], '#').'\n?'. // #}\n?
  146.                 ')
  147.             }sx',
  149.             // verbatim %}
  150.             'lex_block_raw' => '{
  151.                 \s*verbatim\s*
  152.                 (?:'.
  153.                     preg_quote($this->options['whitespace_trim'].$this->options['tag_block'][1], '#').'\s*'. // -%}\s*
  154.                     '|'.
  155.                     preg_quote($this->options['whitespace_line_trim'].$this->options['tag_block'][1], '#').'['.$this->options['whitespace_line_chars'].']*'. // ~%}[ \t\0\x0B]*
  156.                     '|'.
  157.                     preg_quote($this->options['tag_block'][1], '#'). // %}
  158.                 ')
  159.             }Asx',
  161.             'lex_block_line' => '{\s*line\s+(\d+)\s*'.preg_quote($this->options['tag_block'][1], '#').'}As',
  163.             // {{ or {% or {#
  164.             'lex_tokens_start' => '{
  165.                 ('.
  166.                     preg_quote($this->options['tag_variable'][0], '#'). // {{
  167.                     '|'.
  168.                     preg_quote($this->options['tag_block'][0], '#'). // {%
  169.                     '|'.
  170.                     preg_quote($this->options['tag_comment'][0], '#'). // {#
  171.                 ')('.
  172.                     preg_quote($this->options['whitespace_trim'], '#'). // -
  173.                     '|'.
  174.                     preg_quote($this->options['whitespace_line_trim'], '#'). // ~
  175.                 ')?
  176.             }sx',
  177.             'interpolation_start' => '{'.preg_quote($this->options['interpolation'][0], '#').'\s*}A',
  178.             'interpolation_end' => '{\s*'.preg_quote($this->options['interpolation'][1], '#').'}A',
  179.         ];
  181.         $this->isInitialized = true;
  182.     }
  184.     public function tokenize(Source $source): TokenStream
  185.     {
  186.         $this->initialize();
  188.         $this->source = $source;
  189.         $this->code = str_replace(["\r\n", "\r"], "\n", $source->getCode());
  190.         $this->cursor = 0;
  191.         $this->lineno = 1;
  192.         $this->end = \strlen($this->code);
  193.         $this->tokens = [];
  194.         $this->state = self::STATE_DATA;
  195.         $this->states = [];
  196.         $this->brackets = [];
  197.         $this->position = -1;
  199.         // find all token starts in one go
  200.         preg_match_all($this->regexes['lex_tokens_start'], $this->code, $matches, \PREG_OFFSET_CAPTURE);
  201.         $this->positions = $matches;
  203.         while ($this->cursor < $this->end) {
  204.             // dispatch to the lexing functions depending
  205.             // on the current state
  206.             switch ($this->state) {
  207.                 case self::STATE_DATA:
  208.                     $this->lexData();
  209.                     break;
  211.                 case self::STATE_BLOCK:
  212.                     $this->lexBlock();
  213.                     break;
  215.                 case self::STATE_VAR:
  216.                     $this->lexVar();
  217.                     break;
  219.                 case self::STATE_STRING:
  220.                     $this->lexString();
  221.                     break;
  223.                 case self::STATE_INTERPOLATION:
  224.                     $this->lexInterpolation();
  225.                     break;
  226.             }
  227.         }
  229.         $this->pushToken(Token::EOF_TYPE);
  231.         if ($this->brackets) {
  232.             [$expect, $lineno] = array_pop($this->brackets);
  233.             throw new SyntaxError(\sprintf('Unclosed "%s".', $expect), $lineno, $this->source);
  234.         }
  236.         return new TokenStream($this->tokens, $this->source);
  237.     }
  239.     private function lexData(): void
  240.     {
  241.         // if no matches are left we return the rest of the template as simple text token
  242.         if ($this->position == \count($this->positions[0]) - 1) {
  243.             $this->pushToken(Token::TEXT_TYPE, substr($this->code, $this->cursor));
  244.             $this->cursor = $this->end;
  246.             return;
  247.         }
  249.         // Find the first token after the current cursor
  250.         $position = $this->positions[0][++$this->position];
  251.         while ($position[1] < $this->cursor) {
  252.             if ($this->position == \count($this->positions[0]) - 1) {
  253.                 return;
  254.             }
  255.             $position = $this->positions[0][++$this->position];
  256.         }
  258.         // push the template text first
  259.         $text = $textContent = substr($this->code, $this->cursor, $position[1] - $this->cursor);
  261.         // trim?
  262.         if (isset($this->positions[2][$this->position][0])) {
  263.             if ($this->options['whitespace_trim'] === $this->positions[2][$this->position][0]) {
  264.                 // whitespace_trim detected ({%-, {{- or {#-)
  265.                 $text = rtrim($text);
  266.             } elseif ($this->options['whitespace_line_trim'] === $this->positions[2][$this->position][0]) {
  267.                 // whitespace_line_trim detected ({%~, {{~ or {#~)
  268.                 // don't trim \r and \n
  269.                 $text = rtrim($text, " \t\0\x0B");
  270.             }
  271.         }
  272.         $this->pushToken(Token::TEXT_TYPE, $text);
  273.         $this->moveCursor($textContent.$position[0]);
  275.         switch ($this->positions[1][$this->position][0]) {
  276.             case $this->options['tag_comment'][0]:
  277.                 $this->lexComment();
  278.                 break;
  280.             case $this->options['tag_block'][0]:
  281.                 // raw data?
  282.                 if (preg_match($this->regexes['lex_block_raw'], $this->code, $match, 0, $this->cursor)) {
  283.                     $this->moveCursor($match[0]);
  284.                     $this->lexRawData();
  285.                 // {% line \d+ %}
  286.                 } elseif (preg_match($this->regexes['lex_block_line'], $this->code, $match, 0, $this->cursor)) {
  287.                     $this->moveCursor($match[0]);
  288.                     $this->lineno = (int) $match[1];
  289.                 } else {
  290.                     $this->pushToken(Token::BLOCK_START_TYPE);
  291.                     $this->pushState(self::STATE_BLOCK);
  292.                     $this->currentVarBlockLine = $this->lineno;
  293.                 }
  294.                 break;
  296.             case $this->options['tag_variable'][0]:
  297.                 $this->pushToken(Token::VAR_START_TYPE);
  298.                 $this->pushState(self::STATE_VAR);
  299.                 $this->currentVarBlockLine = $this->lineno;
  300.                 break;
  301.         }
  302.     }
  304.     private function lexBlock(): void
  305.     {
  306.         if (!$this->brackets && preg_match($this->regexes['lex_block'], $this->code, $match, 0, $this->cursor)) {
  307.             $this->pushToken(Token::BLOCK_END_TYPE);
  308.             $this->moveCursor($match[0]);
  309.             $this->popState();
  310.         } else {
  311.             $this->lexExpression();
  312.         }
  313.     }
  315.     private function lexVar(): void
  316.     {
  317.         if (!$this->brackets && preg_match($this->regexes['lex_var'], $this->code, $match, 0, $this->cursor)) {
  318.             $this->pushToken(Token::VAR_END_TYPE);
  319.             $this->moveCursor($match[0]);
  320.             $this->popState();
  321.         } else {
  322.             $this->lexExpression();
  323.         }
  324.     }
  326.     private function lexExpression(): void
  327.     {
  328.         // whitespace
  329.         if (preg_match('/\s+/A', $this->code, $match, 0, $this->cursor)) {
  330.             $this->moveCursor($match[0]);
  332.             if ($this->cursor >= $this->end) {
  333.                 throw new SyntaxError(\sprintf('Unclosed "%s".', self::STATE_BLOCK === $this->state ? 'block' : 'variable'), $this->currentVarBlockLine, $this->source);
  334.             }
  335.         }
  337.         // operators
  338.         if (preg_match($this->regexes['operator'], $this->code, $match, 0, $this->cursor)) {
  339.             $operator = preg_replace('/\s+/', ' ', $match[0]);
  340.             if (\in_array($operator, $this->openingBrackets, true)) {
  341.                 $this->checkBrackets($operator);
  342.             }
  343.             $this->pushToken(Token::OPERATOR_TYPE, $operator);
  344.             $this->moveCursor($match[0]);
  345.         }
  346.         // names
  347.         elseif (preg_match(self::REGEX_NAME, $this->code, $match, 0, $this->cursor)) {
  348.             $this->pushToken(Token::NAME_TYPE, $match[0]);
  349.             $this->moveCursor($match[0]);
  350.         }
  351.         // numbers
  352.         elseif (preg_match(self::REGEX_NUMBER, $this->code, $match, 0, $this->cursor)) {
  353.             $this->pushToken(Token::NUMBER_TYPE, 0 + str_replace('_', '', $match[0]));
  354.             $this->moveCursor($match[0]);
  355.         }
  356.         // punctuation
  357.         elseif (str_contains(self::PUNCTUATION, $this->code[$this->cursor])) {
  358.             $this->checkBrackets($this->code[$this->cursor]);
  359.             $this->pushToken(Token::PUNCTUATION_TYPE, $this->code[$this->cursor]);
  360.             ++$this->cursor;
  361.         }
  362.         // strings
  363.         elseif (preg_match(self::REGEX_STRING, $this->code, $match, 0, $this->cursor)) {
  364.             $this->pushToken(Token::STRING_TYPE, $this->stripcslashes(substr($match[0], 1, -1), substr($match[0], 0, 1)));
  365.             $this->moveCursor($match[0]);
  366.         }
  367.         // opening double quoted string
  368.         elseif (preg_match(self::REGEX_DQ_STRING_DELIM, $this->code, $match, 0, $this->cursor)) {
  369.             $this->brackets[] = ['"', $this->lineno];
  370.             $this->pushState(self::STATE_STRING);
  371.             $this->moveCursor($match[0]);
  372.         }
  373.         // inline comment
  374.         elseif (preg_match(self::REGEX_INLINE_COMMENT, $this->code, $match, 0, $this->cursor)) {
  375.             $this->moveCursor($match[0]);
  376.         }
  377.         // unlexable
  378.         else {
  379.             throw new SyntaxError(\sprintf('Unexpected character "%s".', $this->code[$this->cursor]), $this->lineno, $this->source);
  380.         }
  381.     }
  383.     private function stripcslashes(string $str, string $quoteType): string
  384.     {
  385.         $result = '';
  386.         $length = \strlen($str);
  388.         $i = 0;
  389.         while ($i < $length) {
  390.             if (false === $pos = strpos($str, '\\', $i)) {
  391.                 $result .= substr($str, $i);
  392.                 break;
  393.             }
  395.             $result .= substr($str, $i, $pos - $i);
  396.             $i = $pos + 1;
  398.             if ($i >= $length) {
  399.                 $result .= '\\';
  400.                 break;
  401.             }
  403.             $nextChar = $str[$i];
  405.             if (isset(self::SPECIAL_CHARS[$nextChar])) {
  406.                 $result .= self::SPECIAL_CHARS[$nextChar];
  407.             } elseif ('\\' === $nextChar) {
  408.                 $result .= $nextChar;
  409.             } elseif ("'" === $nextChar || '"' === $nextChar) {
  410.                 if ($nextChar !== $quoteType) {
  411.                     trigger_deprecation('twig/twig', '3.12', 'Character "%s" should not be escaped; the "\" character is ignored in Twig 3 but will not be in Twig 4. Please remove the extra "\" character at position %d in "%s" at line %d.', $nextChar, $i + 1, $this->source->getName(), $this->lineno);
  412.                 }
  413.                 $result .= $nextChar;
  414.             } elseif ('#' === $nextChar && $i + 1 < $length && '{' === $str[$i + 1]) {
  415.                 $result .= '#{';
  416.                 ++$i;
  417.             } elseif ('x' === $nextChar && $i + 1 < $length && ctype_xdigit($str[$i + 1])) {
  418.                 $hex = $str[++$i];
  419.                 if ($i + 1 < $length && ctype_xdigit($str[$i + 1])) {
  420.                     $hex .= $str[++$i];
  421.                 }
  422.                 $result .= \chr(hexdec($hex));
  423.             } elseif (ctype_digit($nextChar) && $nextChar < '8') {
  424.                 $octal = $nextChar;
  425.                 while ($i + 1 < $length && ctype_digit($str[$i + 1]) && $str[$i + 1] < '8' && \strlen($octal) < 3) {
  426.                     $octal .= $str[++$i];
  427.                 }
  428.                 $result .= \chr(octdec($octal));
  429.             } else {
  430.                 trigger_deprecation('twig/twig', '3.12', 'Character "%s" should not be escaped; the "\" character is ignored in Twig 3 but will not be in Twig 4. Please remove the extra "\" character at position %d in "%s" at line %d.', $nextChar, $i + 1, $this->source->getName(), $this->lineno);
  431.                 $result .= $nextChar;
  432.             }
  434.             ++$i;
  435.         }
  437.         return $result;
  438.     }
  440.     private function lexRawData(): void
  441.     {
  442.         if (!preg_match($this->regexes['lex_raw_data'], $this->code, $match, \PREG_OFFSET_CAPTURE, $this->cursor)) {
  443.             throw new SyntaxError('Unexpected end of file: Unclosed "verbatim" block.', $this->lineno, $this->source);
  444.         }
  446.         $text = substr($this->code, $this->cursor, $match[0][1] - $this->cursor);
  447.         $this->moveCursor($text.$match[0][0]);
  449.         // trim?
  450.         if (isset($match[1][0])) {
  451.             if ($this->options['whitespace_trim'] === $match[1][0]) {
  452.                 // whitespace_trim detected ({%-, {{- or {#-)
  453.                 $text = rtrim($text);
  454.             } else {
  455.                 // whitespace_line_trim detected ({%~, {{~ or {#~)
  456.                 // don't trim \r and \n
  457.                 $text = rtrim($text, " \t\0\x0B");
  458.             }
  459.         }
  461.         $this->pushToken(Token::TEXT_TYPE, $text);
  462.     }
  464.     private function lexComment(): void
  465.     {
  466.         if (!preg_match($this->regexes['lex_comment'], $this->code, $match, \PREG_OFFSET_CAPTURE, $this->cursor)) {
  467.             throw new SyntaxError('Unclosed comment.', $this->lineno, $this->source);
  468.         }
  470.         $this->moveCursor(substr($this->code, $this->cursor, $match[0][1] - $this->cursor).$match[0][0]);
  471.     }
  473.     private function lexString(): void
  474.     {
  475.         if (preg_match($this->regexes['interpolation_start'], $this->code, $match, 0, $this->cursor)) {
  476.             $this->brackets[] = [$this->options['interpolation'][0], $this->lineno];
  477.             $this->pushToken(Token::INTERPOLATION_START_TYPE);
  478.             $this->moveCursor($match[0]);
  479.             $this->pushState(self::STATE_INTERPOLATION);
  480.         } elseif (preg_match(self::REGEX_DQ_STRING_PART, $this->code, $match, 0, $this->cursor) && '' !== $match[0]) {
  481.             $this->pushToken(Token::STRING_TYPE, $this->stripcslashes($match[0], '"'));
  482.             $this->moveCursor($match[0]);
  483.         } elseif (preg_match(self::REGEX_DQ_STRING_DELIM, $this->code, $match, 0, $this->cursor)) {
  484.             [$expect, $lineno] = array_pop($this->brackets);
  485.             if ('"' != $this->code[$this->cursor]) {
  486.                 throw new SyntaxError(\sprintf('Unclosed "%s".', $expect), $lineno, $this->source);
  487.             }
  489.             $this->popState();
  490.             ++$this->cursor;
  491.         } else {
  492.             // unlexable
  493.             throw new SyntaxError(\sprintf('Unexpected character "%s".', $this->code[$this->cursor]), $this->lineno, $this->source);
  494.         }
  495.     }
  497.     private function lexInterpolation(): void
  498.     {
  499.         $bracket = end($this->brackets);
  500.         if ($this->options['interpolation'][0] === $bracket[0] && preg_match($this->regexes['interpolation_end'], $this->code, $match, 0, $this->cursor)) {
  501.             array_pop($this->brackets);
  502.             $this->pushToken(Token::INTERPOLATION_END_TYPE);
  503.             $this->moveCursor($match[0]);
  504.             $this->popState();
  505.         } else {
  506.             $this->lexExpression();
  507.         }
  508.     }
  510.     private function pushToken($type, $value = ''): void
  511.     {
  512.         // do not push empty text tokens
  513.         if (Token::TEXT_TYPE === $type && '' === $value) {
  514.             return;
  515.         }
  517.         $this->tokens[] = new Token($type, $value, $this->lineno);
  518.     }
  520.     private function moveCursor($text): void
  521.     {
  522.         $this->cursor += \strlen($text);
  523.         $this->lineno += substr_count($text, "\n");
  524.     }
  526.     private function getOperatorRegex(): string
  527.     {
  528.         $expressionParsers = [];
  529.         foreach ($this->env->getExpressionParsers() as $expressionParser) {
  530.             $expressionParsers = array_merge($expressionParsers, [$expressionParser->getName()], $expressionParser->getAliases());
  531.         }
  533.         $expressionParsers = array_combine($expressionParsers, array_map('strlen', $expressionParsers));
  534.         arsort($expressionParsers);
  536.         $regex = [];
  537.         foreach ($expressionParsers as $expressionParser => $length) {
  538.             // an operator that ends with a character must be followed by
  539.             // a whitespace, a parenthesis, an opening map [ or sequence {
  540.             $r = preg_quote($expressionParser, '/');
  541.             if (ctype_alpha($expressionParser[$length - 1])) {
  542.                 $r .= '(?=[\s()\[{])';
  543.             }
  545.             // an operator that begins with a character must not have a dot or pipe before
  546.             if (ctype_alpha($expressionParser[0])) {
  547.                 $r = '(?<![\.\|])'.$r;
  548.             }
  550.             // an operator with a space can be any amount of whitespaces
  551.             $r = preg_replace('/\s+/', '\s+', $r);
  553.             $regex[] = $r;
  554.         }
  556.         return '/'.implode('|', $regex).'/A';
  557.     }
  559.     private function pushState($state): void
  560.     {
  561.         $this->states[] = $this->state;
  562.         $this->state = $state;
  563.     }
  565.     private function popState(): void
  566.     {
  567.         if (0 === \count($this->states)) {
  568.             throw new \LogicException('Cannot pop state without a previous state.');
  569.         }
  571.         $this->state = array_pop($this->states);
  572.     }
  574.     private function checkBrackets(string $code): void
  575.     {
  576.         // opening bracket
  577.         if (\in_array($code, $this->openingBrackets, true)) {
  578.             $this->brackets[] = [$code, $this->lineno];
  579.         } elseif (\in_array($code, $this->closingBrackets, true)) {
  580.             // closing bracket
  581.             if (!$this->brackets) {
  582.                 throw new SyntaxError(\sprintf('Unexpected "%s".', $code), $this->lineno, $this->source);
  583.             }
  585.             [$expect, $lineno] = array_pop($this->brackets);
  586.             if ($code !== str_replace($this->openingBrackets, $this->closingBrackets, $expect)) {
  587.                 throw new SyntaxError(\sprintf('Unclosed "%s".', $expect), $lineno, $this->source);
  588.             }
  589.         }
  590.     }
  591. }