Twig-1.3.0/lib/Twig/Lexer.php
changeset 4 9a001a04b634
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Twig-1.3.0/lib/Twig/Lexer.php	Tue Oct 25 23:56:28 2011 +0200
@@ -0,0 +1,328 @@
+<?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.
+ *
+ * @package    twig
+ * @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 $brackets;
+
+    protected $env;
+    protected $filename;
+    protected $options;
+    protected $operatorRegex;
+
+    const STATE_DATA  = 0;
+    const STATE_BLOCK = 1;
+    const STATE_VAR   = 2;
+
+    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 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' => '-',
+        ), $options);
+    }
+
+    /**
+     * 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;
+        $this->brackets = array();
+
+        while ($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;
+            }
+        }
+
+        $this->pushToken(Twig_Token::EOF_TYPE);
+
+        if (!empty($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()
+    {
+        $pos = $this->end;
+        $append = '';
+
+        // Find the first token after the cursor
+        foreach (array('tag_comment', 'tag_variable', 'tag_block') as $type) {
+            $tmpPos = strpos($this->code, $this->options[$type][0], $this->cursor);
+            if (false !== $tmpPos && $tmpPos < $pos) {
+                $trimBlock = false;
+                $append = '';
+                $pos = $tmpPos;
+                $token = $this->options[$type][0];
+                if (strpos($this->code, $this->options['whitespace_trim'], $pos) === ($pos + strlen($token))) {
+                    $trimBlock = true;
+                    $append = $this->options['whitespace_trim'];
+                }
+            }
+        }
+
+        // if no matches are left we return the rest of the template as simple text token
+        if ($pos === $this->end) {
+            $this->pushToken(Twig_Token::TEXT_TYPE, substr($this->code, $this->cursor));
+            $this->cursor = $this->end;
+            return;
+        }
+
+        // push the template text first
+        $text = $textContent = substr($this->code, $this->cursor, $pos - $this->cursor);
+        if (true === $trimBlock) {
+            $text = rtrim($text);
+        }
+        $this->pushToken(Twig_Token::TEXT_TYPE, $text);
+        $this->moveCursor($textContent.$token.$append);
+
+        switch ($token) {
+            case $this->options['tag_comment'][0]:
+                $this->lexComment();
+                break;
+
+            case $this->options['tag_block'][0]:
+                // raw data?
+                if (preg_match('/\s*raw\s*'.preg_quote($this->options['tag_block'][1], '/').'/As', $this->code, $match, null, $this->cursor)) {
+                    $this->moveCursor($match[0]);
+                    $this->lexRawData();
+                    $this->state = self::STATE_DATA;
+                // {% line \d+ %}
+                } else if (preg_match('/\s*line\s+(\d+)\s*'.preg_quote($this->options['tag_block'][1], '/').'/As', $this->code, $match, null, $this->cursor)) {
+                    $this->moveCursor($match[0]);
+                    $this->lineno = (int) $match[1];
+                    $this->state = self::STATE_DATA;
+                } else {
+                    $this->pushToken(Twig_Token::BLOCK_START_TYPE);
+                    $this->state = self::STATE_BLOCK;
+                }
+                break;
+
+            case $this->options['tag_variable'][0]:
+                $this->pushToken(Twig_Token::VAR_START_TYPE);
+                $this->state = self::STATE_VAR;
+                break;
+        }
+    }
+
+    protected function lexBlock()
+    {
+        $trimTag = preg_quote($this->options['whitespace_trim'].$this->options['tag_block'][1], '/');
+        $endTag = preg_quote($this->options['tag_block'][1], '/');
+
+        if (empty($this->brackets) && preg_match('/\s*(?:'.$trimTag.'\s*|\s*'.$endTag.')\n?/A', $this->code, $match, null, $this->cursor)) {
+            $this->pushToken(Twig_Token::BLOCK_END_TYPE);
+            $this->moveCursor($match[0]);
+            $this->state = self::STATE_DATA;
+        } else {
+            $this->lexExpression();
+        }
+    }
+
+    protected function lexVar()
+    {
+        $trimTag = preg_quote($this->options['whitespace_trim'].$this->options['tag_variable'][1], '/');
+        $endTag = preg_quote($this->options['tag_variable'][1], '/');
+
+        if (empty($this->brackets) && preg_match('/\s*'.$trimTag.'\s*|\s*'.$endTag.'/A', $this->code, $match, null, $this->cursor)) {
+            $this->pushToken(Twig_Token::VAR_END_TYPE);
+            $this->moveCursor($match[0]);
+            $this->state = self::STATE_DATA;
+        } 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('Unexpected end of file: Unclosed "%s"', $this->state === self::STATE_BLOCK ? 'block' : 'variable'));
+            }
+        }
+
+        // operators
+        if (preg_match($this->getOperatorRegex(), $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)) {
+            $this->pushToken(Twig_Token::NUMBER_TYPE, ctype_digit($match[0]) ? (int) $match[0] : (float) $match[0]);
+            $this->moveCursor($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]);
+        }
+        // unlexable
+        else {
+            throw new Twig_Error_Syntax(sprintf('Unexpected character "%s"', $this->code[$this->cursor]), $this->lineno, $this->filename);
+        }
+    }
+
+    protected function lexRawData()
+    {
+        if (!preg_match('/'.preg_quote($this->options['tag_block'][0], '/').'\s*endraw\s*'.preg_quote($this->options['tag_block'][1], '/').'/s', $this->code, $match, PREG_OFFSET_CAPTURE, $this->cursor)) {
+            throw new Twig_Error_Syntax(sprintf('Unexpected end of file: Unclosed "block"'));
+        }
+        $text = substr($this->code, $this->cursor, $match[0][1] - $this->cursor);
+        $this->pushToken(Twig_Token::TEXT_TYPE, $text);
+        $this->moveCursor($text.$match[0][0]);
+    }
+
+    protected function lexComment()
+    {
+        $commentEndRegex = '/(?:'.preg_quote($this->options['whitespace_trim'], '/')
+                           .preg_quote($this->options['tag_comment'][1], '/').'\s*|'
+                           .preg_quote($this->options['tag_comment'][1], '/').')\n?/s';
+
+        if (!preg_match($commentEndRegex, $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 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()
+    {
+        if (null !== $this->operatorRegex) {
+            return $this->operatorRegex;
+        }
+
+        $operators = array_merge(
+            array('='),
+            array_keys($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, '/').'(?=[ ()])';
+            } else {
+                $regex[] = preg_quote($operator, '/');
+            }
+        }
+
+        return $this->operatorRegex = '/'.implode('|', $regex).'/A';
+    }
+}