Twig-1.3.0/lib/Twig/Parser.php
changeset 4 9a001a04b634
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Twig-1.3.0/lib/Twig/Parser.php	Tue Oct 25 23:56:28 2011 +0200
@@ -0,0 +1,339 @@
+<?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.
+ */
+
+/**
+ * Default parser implementation.
+ *
+ * @package twig
+ * @author  Fabien Potencier <fabien@symfony.com>
+ */
+class Twig_Parser implements Twig_ParserInterface
+{
+    protected $stream;
+    protected $parent;
+    protected $handlers;
+    protected $visitors;
+    protected $expressionParser;
+    protected $blocks;
+    protected $blockStack;
+    protected $macros;
+    protected $env;
+    protected $reservedMacroNames;
+    protected $importedFunctions;
+    protected $tmpVarCount;
+    protected $traits;
+
+    /**
+     * Constructor.
+     *
+     * @param Twig_Environment $env A Twig_Environment instance
+     */
+    public function __construct(Twig_Environment $env)
+    {
+        $this->env = $env;
+    }
+
+    public function getVarName()
+    {
+        return sprintf('__internal_%s_%d', substr($this->env->getTemplateClass($this->stream->getFilename()), strlen($this->env->getTemplateClassPrefix())), ++$this->tmpVarCount);
+    }
+
+    /**
+     * Converts a token stream to a node tree.
+     *
+     * @param  Twig_TokenStream $stream A token stream instance
+     *
+     * @return Twig_Node_Module A node tree
+     */
+    public function parse(Twig_TokenStream $stream)
+    {
+        $this->tmpVarCount = 0;
+
+        // tag handlers
+        $this->handlers = $this->env->getTokenParsers();
+        $this->handlers->setParser($this);
+
+        // node visitors
+        $this->visitors = $this->env->getNodeVisitors();
+
+        if (null === $this->expressionParser) {
+            $this->expressionParser = new Twig_ExpressionParser($this, $this->env->getUnaryOperators(), $this->env->getBinaryOperators());
+        }
+
+        $this->stream = $stream;
+        $this->parent = null;
+        $this->blocks = array();
+        $this->macros = array();
+        $this->traits = array();
+        $this->blockStack = array();
+        $this->importedFunctions = array(array());
+
+        try {
+            $body = $this->subparse(null);
+
+            if (null !== $this->parent) {
+                if (null === $body = $this->filterBodyNodes($body)) {
+                    $body = new Twig_Node();
+                }
+            }
+        } catch (Twig_Error_Syntax $e) {
+            if (null === $e->getTemplateFile()) {
+                $e->setTemplateFile($this->stream->getFilename());
+            }
+
+            throw $e;
+        }
+
+        $node = new Twig_Node_Module($body, $this->parent, new Twig_Node($this->blocks), new Twig_Node($this->macros), new Twig_Node($this->traits), $this->stream->getFilename());
+
+        $traverser = new Twig_NodeTraverser($this->env, $this->visitors);
+
+        return $traverser->traverse($node);
+    }
+
+    public function subparse($test, $dropNeedle = false)
+    {
+        $lineno = $this->getCurrentToken()->getLine();
+        $rv = array();
+        while (!$this->stream->isEOF()) {
+            switch ($this->getCurrentToken()->getType()) {
+                case Twig_Token::TEXT_TYPE:
+                    $token = $this->stream->next();
+                    $rv[] = new Twig_Node_Text($token->getValue(), $token->getLine());
+                    break;
+
+                case Twig_Token::VAR_START_TYPE:
+                    $token = $this->stream->next();
+                    $expr = $this->expressionParser->parseExpression();
+                    $this->stream->expect(Twig_Token::VAR_END_TYPE);
+                    $rv[] = new Twig_Node_Print($expr, $token->getLine());
+                    break;
+
+                case Twig_Token::BLOCK_START_TYPE:
+                    $this->stream->next();
+                    $token = $this->getCurrentToken();
+
+                    if ($token->getType() !== Twig_Token::NAME_TYPE) {
+                        throw new Twig_Error_Syntax('A block must start with a tag name', $token->getLine(), $this->stream->getFilename());
+                    }
+
+                    if (null !== $test && call_user_func($test, $token)) {
+                        if ($dropNeedle) {
+                            $this->stream->next();
+                        }
+
+                        if (1 === count($rv)) {
+                            return $rv[0];
+                        }
+
+                        return new Twig_Node($rv, array(), $lineno);
+                    }
+
+                    $subparser = $this->handlers->getTokenParser($token->getValue());
+                    if (null === $subparser) {
+                        if (null !== $test) {
+                            throw new Twig_Error_Syntax(sprintf('Unexpected tag name "%s" (expecting closing tag for the "%s" tag defined near line %s)', $token->getValue(), $test[0]->getTag(), $lineno), $token->getLine(), $this->stream->getFilename());
+                        }
+
+                        throw new Twig_Error_Syntax(sprintf('Unknown tag name "%s"', $token->getValue()), $token->getLine(), $this->stream->getFilename());
+                    }
+
+                    $this->stream->next();
+
+                    $node = $subparser->parse($token);
+                    if (null !== $node) {
+                        $rv[] = $node;
+                    }
+                    break;
+
+                default:
+                    throw new Twig_Error_Syntax('Lexer or parser ended up in unsupported state.', -1, $this->stream->getFilename());
+            }
+        }
+
+        if (1 === count($rv)) {
+            return $rv[0];
+        }
+
+        return new Twig_Node($rv, array(), $lineno);
+    }
+
+    public function addHandler($name, $class)
+    {
+        $this->handlers[$name] = $class;
+    }
+
+    public function addNodeVisitor(Twig_NodeVisitorInterface $visitor)
+    {
+        $this->visitors[] = $visitor;
+    }
+
+    public function getBlockStack()
+    {
+        return $this->blockStack;
+    }
+
+    public function peekBlockStack()
+    {
+        return $this->blockStack[count($this->blockStack) - 1];
+    }
+
+    public function popBlockStack()
+    {
+        array_pop($this->blockStack);
+    }
+
+    public function pushBlockStack($name)
+    {
+        $this->blockStack[] = $name;
+    }
+
+    public function hasBlock($name)
+    {
+        return isset($this->blocks[$name]);
+    }
+
+    public function setBlock($name, $value)
+    {
+        $this->blocks[$name] = $value;
+    }
+
+    public function hasMacro($name)
+    {
+        return isset($this->macros[$name]);
+    }
+
+    public function setMacro($name, Twig_Node_Macro $node)
+    {
+        if (null === $this->reservedMacroNames) {
+            $this->reservedMacroNames = array();
+            $r = new ReflectionClass($this->env->getBaseTemplateClass());
+            foreach ($r->getMethods() as $method) {
+                $this->reservedMacroNames[] = $method->getName();
+            }
+        }
+
+        if (in_array($name, $this->reservedMacroNames)) {
+            throw new Twig_Error_Syntax(sprintf('"%s" cannot be used as a macro name as it is a reserved keyword', $name), $node->getLine());
+        }
+
+        $this->macros[$name] = $node;
+    }
+
+    public function addTrait($trait)
+    {
+        $this->traits[] = $trait;
+    }
+
+    public function hasTraits()
+    {
+        return count($this->traits) > 0;
+    }
+
+    public function addImportedFunction($alias, $name, Twig_Node_Expression $node)
+    {
+        $this->importedFunctions[0][$alias] = array('name' => $name, 'node' => $node);
+    }
+
+    public function getImportedFunction($alias)
+    {
+        foreach ($this->importedFunctions as $functions) {
+            if (isset($functions[$alias])) {
+                return $functions[$alias];
+            }
+        }
+    }
+
+    public function isMainScope()
+    {
+        return 1 === count($this->importedFunctions);
+    }
+
+    public function pushLocalScope()
+    {
+        array_unshift($this->importedFunctions, array());
+    }
+
+    public function popLocalScope()
+    {
+        array_shift($this->importedFunctions);
+    }
+
+    /**
+     * Gets the expression parser.
+     *
+     * @return Twig_ExpressionParser The expression parser
+     */
+    public function getExpressionParser()
+    {
+        return $this->expressionParser;
+    }
+
+    public function getParent()
+    {
+        return $this->parent;
+    }
+
+    public function setParent($parent)
+    {
+        $this->parent = $parent;
+    }
+
+    /**
+     * Gets the token stream.
+     *
+     * @return Twig_TokenStream The token stream
+     */
+    public function getStream()
+    {
+        return $this->stream;
+    }
+
+    /**
+     * Gets the current token.
+     *
+     * @return Twig_Token The current token
+     */
+    public function getCurrentToken()
+    {
+        return $this->stream->getCurrent();
+    }
+
+    protected function filterBodyNodes(Twig_NodeInterface $node)
+    {
+        // check that the body does not contain non-empty output nodes
+        if (
+            ($node instanceof Twig_Node_Text && !ctype_space($node->getAttribute('data')))
+            ||
+            (!$node instanceof Twig_Node_Text && !$node instanceof Twig_Node_BlockReference && $node instanceof Twig_NodeOutputInterface)
+        ) {
+            throw new Twig_Error_Syntax('A template that extends another one cannot have a body.', $node->getLine(), $this->stream->getFilename());
+        }
+
+        // bypass "set" nodes as they "capture" the output
+        if ($node instanceof Twig_Node_Set) {
+            return $node;
+        }
+
+        if ($node instanceof Twig_NodeOutputInterface) {
+            return;
+        }
+
+        foreach ($node as $k => $n) {
+            if (null !== $n && null === $n = $this->filterBodyNodes($n)) {
+                $node->removeNode($k);
+            }
+        }
+
+        return $node;
+    }
+}