1 files changed, 408 insertions, 0 deletions

diff --git a/inc/Twig/Lexer.php b/inc/Twig/Lexer.php
new file mode 100644
index 00000000..000b038e
--- /dev/null
+++ b/inc/Twig/Lexer.php
@@ -0,0 +1,408 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) 2009 Fabien Potencier
+ * (c) 2009 Armin Ronacher
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Lexes a template string.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class Twig_Lexer implements Twig_LexerInterface
+{
+    protected $tokens;
+    protected $code;
+    protected $cursor;
+    protected $lineno;
+    protected $end;
+    protected $state;
+    protected $states;
+    protected $brackets;
+    protected $env;
+    protected $filename;
+    protected $options;
+    protected $regexes;
+    protected $position;
+    protected $positions;
+    protected $currentVarBlockLine;
+
+    const STATE_DATA            = 0;
+    const STATE_BLOCK           = 1;
+    const STATE_VAR             = 2;
+    const STATE_STRING          = 3;
+    const STATE_INTERPOLATION   = 4;
+
+    const REGEX_NAME            = '/[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*/A';
+    const REGEX_NUMBER          = '/[0-9]+(?:\.[0-9]+)?/A';
+    const REGEX_STRING          = '/"([^#"\\\\]*(?:\\\\.[^#"\\\\]*)*)"|\'([^\'\\\\]*(?:\\\\.[^\'\\\\]*)*)\'/As';
+    const REGEX_DQ_STRING_DELIM = '/"/A';
+    const REGEX_DQ_STRING_PART  = '/[^#"\\\\]*(?:(?:\\\\.|#(?!\{))[^#"\\\\]*)*/As';
+    const PUNCTUATION           = '()[]{}?:.,|';
+
+    public function __construct(Twig_Environment $env, array $options = array())
+    {
+        $this->env = $env;
+
+        $this->options = array_merge(array(
+            'tag_comment'     => array('{#', '#}'),
+            'tag_block'       => array('{%', '%}'),
+            'tag_variable'    => array('{{', '}}'),
+            'whitespace_trim' => '-',
+            'interpolation'   => array('#{', '}'),
+        ), $options);
+
+        $this->regexes = array(
+            'lex_var'             => '/\s*'.preg_quote($this->options['whitespace_trim'].$this->options['tag_variable'][1], '/').'\s*|\s*'.preg_quote($this->options['tag_variable'][1], '/').'/A',
+            'lex_block'           => '/\s*(?:'.preg_quote($this->options['whitespace_trim'].$this->options['tag_block'][1], '/').'\s*|\s*'.preg_quote($this->options['tag_block'][1], '/').')\n?/A',
+            'lex_raw_data'        => '/('.preg_quote($this->options['tag_block'][0].$this->options['whitespace_trim'], '/').'|'.preg_quote($this->options['tag_block'][0], '/').')\s*(?:end%s)\s*(?:'.preg_quote($this->options['whitespace_trim'].$this->options['tag_block'][1], '/').'\s*|\s*'.preg_quote($this->options['tag_block'][1], '/').')/s',
+            'operator'            => $this->getOperatorRegex(),
+            'lex_comment'         => '/(?:'.preg_quote($this->options['whitespace_trim'], '/').preg_quote($this->options['tag_comment'][1], '/').'\s*|'.preg_quote($this->options['tag_comment'][1], '/').')\n?/s',
+            'lex_block_raw'       => '/\s*(raw|verbatim)\s*(?:'.preg_quote($this->options['whitespace_trim'].$this->options['tag_block'][1], '/').'\s*|\s*'.preg_quote($this->options['tag_block'][1], '/').')/As',
+            'lex_block_line'      => '/\s*line\s+(\d+)\s*'.preg_quote($this->options['tag_block'][1], '/').'/As',
+            'lex_tokens_start'    => '/('.preg_quote($this->options['tag_variable'][0], '/').'|'.preg_quote($this->options['tag_block'][0], '/').'|'.preg_quote($this->options['tag_comment'][0], '/').')('.preg_quote($this->options['whitespace_trim'], '/').')?/s',
+            'interpolation_start' => '/'.preg_quote($this->options['interpolation'][0], '/').'\s*/A',
+            'interpolation_end'   => '/\s*'.preg_quote($this->options['interpolation'][1], '/').'/A',
+        );
+    }
+
+    /**
+     * Tokenizes a source code.
+     *
+     * @param string $code     The source code
+     * @param string $filename A unique identifier for the source code
+     *
+     * @return Twig_TokenStream A token stream instance
+     */
+    public function tokenize($code, $filename = null)
+    {
+        if (function_exists('mb_internal_encoding') && ((int) ini_get('mbstring.func_overload')) & 2) {
+            $mbEncoding = mb_internal_encoding();
+            mb_internal_encoding('ASCII');
+        }
+
+        $this->code = str_replace(array("\r\n", "\r"), "\n", $code);
+        $this->filename = $filename;
+        $this->cursor = 0;
+        $this->lineno = 1;
+        $this->end = strlen($this->code);
+        $this->tokens = array();
+        $this->state = self::STATE_DATA;
+        $this->states = array();
+        $this->brackets = array();
+        $this->position = -1;
+
+        // find all token starts in one go
+        preg_match_all($this->regexes['lex_tokens_start'], $this->code, $matches, PREG_OFFSET_CAPTURE);
+        $this->positions = $matches;
+
+        while ($this->cursor < $this->end) {
+            // dispatch to the lexing functions depending
+            // on the current state
+            switch ($this->state) {
+                case self::STATE_DATA:
+                    $this->lexData();
+                    break;
+
+                case self::STATE_BLOCK:
+                    $this->lexBlock();
+                    break;
+
+                case self::STATE_VAR:
+                    $this->lexVar();
+                    break;
+
+                case self::STATE_STRING:
+                    $this->lexString();
+                    break;
+
+                case self::STATE_INTERPOLATION:
+                    $this->lexInterpolation();
+                    break;
+            }
+        }
+
+        $this->pushToken(Twig_Token::EOF_TYPE);
+
+        if (!empty($this->brackets)) {
+            list($expect, $lineno) = array_pop($this->brackets);
+            throw new Twig_Error_Syntax(sprintf('Unclosed "%s"', $expect), $lineno, $this->filename);
+        }
+
+        if (isset($mbEncoding)) {
+            mb_internal_encoding($mbEncoding);
+        }
+
+        return new Twig_TokenStream($this->tokens, $this->filename);
+    }
+
+    protected function lexData()
+    {
+        // if no matches are left we return the rest of the template as simple text token
+        if ($this->position == count($this->positions[0]) - 1) {
+            $this->pushToken(Twig_Token::TEXT_TYPE, substr($this->code, $this->cursor));
+            $this->cursor = $this->end;
+
+            return;
+        }
+
+        // Find the first token after the current cursor
+        $position = $this->positions[0][++$this->position];
+        while ($position[1] < $this->cursor) {
+            if ($this->position == count($this->positions[0]) - 1) {
+                return;
+            }
+            $position = $this->positions[0][++$this->position];
+        }
+
+        // push the template text first
+        $text = $textContent = substr($this->code, $this->cursor, $position[1] - $this->cursor);
+        if (isset($this->positions[2][$this->position][0])) {
+            $text = rtrim($text);
+        }
+        $this->pushToken(Twig_Token::TEXT_TYPE, $text);
+        $this->moveCursor($textContent.$position[0]);
+
+        switch ($this->positions[1][$this->position][0]) {
+            case $this->options['tag_comment'][0]:
+                $this->lexComment();
+                break;
+
+            case $this->options['tag_block'][0]:
+                // raw data?
+                if (preg_match($this->regexes['lex_block_raw'], $this->code, $match, null, $this->cursor)) {
+                    $this->moveCursor($match[0]);
+                    $this->lexRawData($match[1]);
+                // {% line \d+ %}
+                } elseif (preg_match($this->regexes['lex_block_line'], $this->code, $match, null, $this->cursor)) {
+                    $this->moveCursor($match[0]);
+                    $this->lineno = (int) $match[1];
+                } else {
+                    $this->pushToken(Twig_Token::BLOCK_START_TYPE);
+                    $this->pushState(self::STATE_BLOCK);
+                    $this->currentVarBlockLine = $this->lineno;
+                }
+                break;
+
+            case $this->options['tag_variable'][0]:
+                $this->pushToken(Twig_Token::VAR_START_TYPE);
+                $this->pushState(self::STATE_VAR);
+                $this->currentVarBlockLine = $this->lineno;
+                break;
+        }
+    }
+
+    protected function lexBlock()
+    {
+        if (empty($this->brackets) && preg_match($this->regexes['lex_block'], $this->code, $match, null, $this->cursor)) {
+            $this->pushToken(Twig_Token::BLOCK_END_TYPE);
+            $this->moveCursor($match[0]);
+            $this->popState();
+        } else {
+            $this->lexExpression();
+        }
+    }
+
+    protected function lexVar()
+    {
+        if (empty($this->brackets) && preg_match($this->regexes['lex_var'], $this->code, $match, null, $this->cursor)) {
+            $this->pushToken(Twig_Token::VAR_END_TYPE);
+            $this->moveCursor($match[0]);
+            $this->popState();
+        } else {
+            $this->lexExpression();
+        }
+    }
+
+    protected function lexExpression()
+    {
+        // whitespace
+        if (preg_match('/\s+/A', $this->code, $match, null, $this->cursor)) {
+            $this->moveCursor($match[0]);
+
+            if ($this->cursor >= $this->end) {
+                throw new Twig_Error_Syntax(sprintf('Unclosed "%s"', $this->state === self::STATE_BLOCK ? 'block' : 'variable'), $this->currentVarBlockLine, $this->filename);
+            }
+        }
+
+        // operators
+        if (preg_match($this->regexes['operator'], $this->code, $match, null, $this->cursor)) {
+            $this->pushToken(Twig_Token::OPERATOR_TYPE, $match[0]);
+            $this->moveCursor($match[0]);
+        }
+        // names
+        elseif (preg_match(self::REGEX_NAME, $this->code, $match, null, $this->cursor)) {
+            $this->pushToken(Twig_Token::NAME_TYPE, $match[0]);
+            $this->moveCursor($match[0]);
+        }
+        // numbers
+        elseif (preg_match(self::REGEX_NUMBER, $this->code, $match, null, $this->cursor)) {
+            $number = (float) $match[0];  // floats
+            if (ctype_digit($match[0]) && $number <= PHP_INT_MAX) {
+                $number = (int) $match[0]; // integers lower than the maximum
+            }
+            $this->pushToken(Twig_Token::NUMBER_TYPE, $number);
+            $this->moveCursor($match[0]);
+        }
+        // punctuation
+        elseif (false !== strpos(self::PUNCTUATION, $this->code[$this->cursor])) {
+            // opening bracket
+            if (false !== strpos('([{', $this->code[$this->cursor])) {
+                $this->brackets[] = array($this->code[$this->cursor], $this->lineno);
+            }
+            // closing bracket
+            elseif (false !== strpos(')]}', $this->code[$this->cursor])) {
+                if (empty($this->brackets)) {
+                    throw new Twig_Error_Syntax(sprintf('Unexpected "%s"', $this->code[$this->cursor]), $this->lineno, $this->filename);
+                }
+
+                list($expect, $lineno) = array_pop($this->brackets);
+                if ($this->code[$this->cursor] != strtr($expect, '([{', ')]}')) {
+                    throw new Twig_Error_Syntax(sprintf('Unclosed "%s"', $expect), $lineno, $this->filename);
+                }
+            }
+
+            $this->pushToken(Twig_Token::PUNCTUATION_TYPE, $this->code[$this->cursor]);
+            ++$this->cursor;
+        }
+        // strings
+        elseif (preg_match(self::REGEX_STRING, $this->code, $match, null, $this->cursor)) {
+            $this->pushToken(Twig_Token::STRING_TYPE, stripcslashes(substr($match[0], 1, -1)));
+            $this->moveCursor($match[0]);
+        }
+        // opening double quoted string
+        elseif (preg_match(self::REGEX_DQ_STRING_DELIM, $this->code, $match, null, $this->cursor)) {
+            $this->brackets[] = array('"', $this->lineno);
+            $this->pushState(self::STATE_STRING);
+            $this->moveCursor($match[0]);
+        }
+        // unlexable
+        else {
+            throw new Twig_Error_Syntax(sprintf('Unexpected character "%s"', $this->code[$this->cursor]), $this->lineno, $this->filename);
+        }
+    }
+
+    protected function lexRawData($tag)
+    {
+        if (!preg_match(str_replace('%s', $tag, $this->regexes['lex_raw_data']), $this->code, $match, PREG_OFFSET_CAPTURE, $this->cursor)) {
+            throw new Twig_Error_Syntax(sprintf('Unexpected end of file: Unclosed "%s" block', $tag), $this->lineno, $this->filename);
+        }
+
+        $text = substr($this->code, $this->cursor, $match[0][1] - $this->cursor);
+        $this->moveCursor($text.$match[0][0]);
+
+        if (false !== strpos($match[1][0], $this->options['whitespace_trim'])) {
+            $text = rtrim($text);
+        }
+
+        $this->pushToken(Twig_Token::TEXT_TYPE, $text);
+    }
+
+    protected function lexComment()
+    {
+        if (!preg_match($this->regexes['lex_comment'], $this->code, $match, PREG_OFFSET_CAPTURE, $this->cursor)) {
+            throw new Twig_Error_Syntax('Unclosed comment', $this->lineno, $this->filename);
+        }
+
+        $this->moveCursor(substr($this->code, $this->cursor, $match[0][1] - $this->cursor).$match[0][0]);
+    }
+
+    protected function lexString()
+    {
+        if (preg_match($this->regexes['interpolation_start'], $this->code, $match, null, $this->cursor)) {
+            $this->brackets[] = array($this->options['interpolation'][0], $this->lineno);
+            $this->pushToken(Twig_Token::INTERPOLATION_START_TYPE);
+            $this->moveCursor($match[0]);
+            $this->pushState(self::STATE_INTERPOLATION);
+
+        } elseif (preg_match(self::REGEX_DQ_STRING_PART, $this->code, $match, null, $this->cursor) && strlen($match[0]) > 0) {
+            $this->pushToken(Twig_Token::STRING_TYPE, stripcslashes($match[0]));
+            $this->moveCursor($match[0]);
+
+        } elseif (preg_match(self::REGEX_DQ_STRING_DELIM, $this->code, $match, null, $this->cursor)) {
+
+            list($expect, $lineno) = array_pop($this->brackets);
+            if ($this->code[$this->cursor] != '"') {
+                throw new Twig_Error_Syntax(sprintf('Unclosed "%s"', $expect), $lineno, $this->filename);
+            }
+
+            $this->popState();
+            ++$this->cursor;
+        }
+    }
+
+    protected function lexInterpolation()
+    {
+        $bracket = end($this->brackets);
+        if ($this->options['interpolation'][0] === $bracket[0] && preg_match($this->regexes['interpolation_end'], $this->code, $match, null, $this->cursor)) {
+            array_pop($this->brackets);
+            $this->pushToken(Twig_Token::INTERPOLATION_END_TYPE);
+            $this->moveCursor($match[0]);
+            $this->popState();
+        } else {
+            $this->lexExpression();
+        }
+    }
+
+    protected function pushToken($type, $value = '')
+    {
+        // do not push empty text tokens
+        if (Twig_Token::TEXT_TYPE === $type && '' === $value) {
+            return;
+        }
+
+        $this->tokens[] = new Twig_Token($type, $value, $this->lineno);
+    }
+
+    protected function moveCursor($text)
+    {
+        $this->cursor += strlen($text);
+        $this->lineno += substr_count($text, "\n");
+    }
+
+    protected function getOperatorRegex()
+    {
+        $operators = array_merge(
+            array('='),
+            array_keys($this->env->getUnaryOperators()),
+            array_keys($this->env->getBinaryOperators())
+        );
+
+        $operators = array_combine($operators, array_map('strlen', $operators));
+        arsort($operators);
+
+        $regex = array();
+        foreach ($operators as $operator => $length) {
+            // an operator that ends with a character must be followed by
+            // a whitespace or a parenthesis
+            if (ctype_alpha($operator[$length - 1])) {
+                $regex[] = preg_quote($operator, '/').'(?=[\s()])';
+            } else {
+                $regex[] = preg_quote($operator, '/');
+            }
+        }
+
+        return '/'.implode('|', $regex).'/A';
+    }
+
+    protected function pushState($state)
+    {
+        $this->states[] = $this->state;
+        $this->state = $state;
+    }
+
+    protected function popState()
+    {
+        if (0 === count($this->states)) {
+            throw new Exception('Cannot pop state without a previous state');
+        }
+
+        $this->state = array_pop($this->states);
+    }
+}