WB 2.08.x

<?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 $stack = array();

    protected $stream;

    protected $parent;

    protected $handlers;

    protected $visitors;

    protected $expressionParser;

    protected $blocks;

    protected $blockStack;

    protected $macros;

    protected $env;

    protected $reservedMacroNames;

    protected $importedSymbols;

    protected $traits;

    protected $embeddedTemplates = array();

    /**

     * Constructor.

     *

     * @param Twig_Environment $env A Twig_Environment instance

     */

    public function __construct(Twig_Environment $env)

    {

        $this->env = $env;

    }

    public function getEnvironment()

    {

        return $this->env;

    }

    public function getVarName()

    {

        return sprintf('__internal_%s', hash('sha1', uniqid(mt_rand(), true), false));

    }

    public function getFilename()

    {

        return $this->stream->getFilename();

    }

    /**

     * 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, $test = null, $dropNeedle = false)

    {

        // push all variables into the stack to keep the current state of the parser

        $vars = get_object_vars($this);

        unset($vars['stack'], $vars['env'], $vars['handlers'], $vars['visitors'], $vars['expressionParser']);

        $this->stack[] = $vars;

        // tag handlers

        if (null === $this->handlers) {

            $this->handlers = $this->env->getTokenParsers();

            $this->handlers->setParser($this);

        }

        // node visitors

        if (null === $this->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->importedSymbols = array(array());

        $this->embeddedTemplates = array();

        try {

            $body = $this->subparse($test, $dropNeedle);

            if (null !== $this->parent) {

                if (null === $body = $this->filterBodyNodes($body)) {

                    $body = new Twig_Node();

                }

            }

        } catch (Twig_Error_Syntax $e) {

            if (!$e->getTemplateFile()) {

                $e->setTemplateFile($this->getFilename());

            }

            if (!$e->getTemplateLine()) {

                $e->setTemplateLine($this->stream->getCurrent()->getLine());

            }

            throw $e;

        }

        $node = new Twig_Node_Module(new Twig_Node_Body(array($body)), $this->parent, new Twig_Node($this->blocks), new Twig_Node($this->macros), new Twig_Node($this->traits), $this->embeddedTemplates, $this->getFilename());

        $traverser = new Twig_NodeTraverser($this->env, $this->visitors);

        $node = $traverser->traverse($node);

        // restore previous stack so previous parse() call can resume working

        foreach (array_pop($this->stack) as $key => $val) {

            $this->$key = $val;

        }

        return $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->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) {

                            $error = sprintf('Unexpected tag name "%s"', $token->getValue());

                            if (is_array($test) && isset($test[0]) && $test[0] instanceof Twig_TokenParserInterface) {

                                $error .= sprintf(' (expecting closing tag for the "%s" tag defined near line %s)', $test[0]->getTag(), $lineno);

                            }

                            throw new Twig_Error_Syntax($error, $token->getLine(), $this->getFilename());

                        }

                        $message = sprintf('Unknown tag name "%s"', $token->getValue());

                        if ($alternatives = $this->env->computeAlternatives($token->getValue(), array_keys($this->env->getTags()))) {

                            $message = sprintf('%s. Did you mean "%s"', $message, implode('", "', $alternatives));

                        }

                        throw new Twig_Error_Syntax($message, $token->getLine(), $this->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.', 0, $this->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 getBlock($name)

    {

        return $this->blocks[$name];

    }

    public function setBlock($name, $value)

    {

        $this->blocks[$name] = new Twig_Node_Body(array($value), array(), $value->getLine());

    }

    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->getFilename());

        }

        $this->macros[$name] = $node;

    }

    public function addTrait($trait)

    {

        $this->traits[] = $trait;

    }

    public function hasTraits()

    {

        return count($this->traits) > 0;

    }

    public function embedTemplate(Twig_Node_Module $template)

    {

        $template->setIndex(mt_rand());

        $this->embeddedTemplates[] = $template;

    }

    public function addImportedSymbol($type, $alias, $name = null, Twig_Node_Expression $node = null)

    {

        $this->importedSymbols[0][$type][$alias] = array('name' => $name, 'node' => $node);

    }

    public function getImportedSymbol($type, $alias)

    {

        foreach ($this->importedSymbols as $functions) {

            if (isset($functions[$type][$alias])) {

                return $functions[$type][$alias];

            }

        }

    }

    public function isMainScope()

    {

        return 1 === count($this->importedSymbols);

    }

    public function pushLocalScope()

    {

        array_unshift($this->importedSymbols, array());

    }

    public function popLocalScope()

    {

        array_shift($this->importedSymbols);

    }

    /**

     * 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)

        ) {

            if (false !== strpos((string) $node, chr(0xEF).chr(0xBB).chr(0xBF))) {

                throw new Twig_Error_Syntax('A template that extends another one cannot have a body but a byte order mark (BOM) has been detected; it must be removed.', $node->getLine(), $this->getFilename());

            }

            throw new Twig_Error_Syntax('A template that extends another one cannot have a body.', $node->getLine(), $this->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;

    }

}