add Twig & refactor poche

4 files changed, 636 insertions, 0 deletions

diff --git a/inc/Twig/NodeVisitor/Escaper.php b/inc/Twig/NodeVisitor/Escaper.php
new file mode 100644
index 00000000..cc4b3d71
--- /dev/null
+++ b/inc/Twig/NodeVisitor/Escaper.php
@@ -0,0 +1,167 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) 2009 Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Twig_NodeVisitor_Escaper implements output escaping.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class Twig_NodeVisitor_Escaper implements Twig_NodeVisitorInterface
+{
+    protected $statusStack = array();
+    protected $blocks = array();
+    protected $safeAnalysis;
+    protected $traverser;
+    protected $defaultStrategy = false;
+    protected $safeVars = array();
+
+    public function __construct()
+    {
+        $this->safeAnalysis = new Twig_NodeVisitor_SafeAnalysis();
+    }
+
+    /**
+     * Called before child nodes are visited.
+     *
+     * @param Twig_NodeInterface $node The node to visit
+     * @param Twig_Environment   $env  The Twig environment instance
+     *
+     * @return Twig_NodeInterface The modified node
+     */
+    public function enterNode(Twig_NodeInterface $node, Twig_Environment $env)
+    {
+        if ($node instanceof Twig_Node_Module) {
+            if ($env->hasExtension('escaper') && $defaultStrategy = $env->getExtension('escaper')->getDefaultStrategy($node->getAttribute('filename'))) {
+                $this->defaultStrategy = $defaultStrategy;
+            }
+            $this->safeVars = array();
+        } elseif ($node instanceof Twig_Node_AutoEscape) {
+            $this->statusStack[] = $node->getAttribute('value');
+        } elseif ($node instanceof Twig_Node_Block) {
+            $this->statusStack[] = isset($this->blocks[$node->getAttribute('name')]) ? $this->blocks[$node->getAttribute('name')] : $this->needEscaping($env);
+        } elseif ($node instanceof Twig_Node_Import) {
+            $this->safeVars[] = $node->getNode('var')->getAttribute('name');
+        }
+
+        return $node;
+    }
+
+    /**
+     * Called after child nodes are visited.
+     *
+     * @param Twig_NodeInterface $node The node to visit
+     * @param Twig_Environment   $env  The Twig environment instance
+     *
+     * @return Twig_NodeInterface The modified node
+     */
+    public function leaveNode(Twig_NodeInterface $node, Twig_Environment $env)
+    {
+        if ($node instanceof Twig_Node_Module) {
+            $this->defaultStrategy = false;
+            $this->safeVars = array();
+        } elseif ($node instanceof Twig_Node_Expression_Filter) {
+            return $this->preEscapeFilterNode($node, $env);
+        } elseif ($node instanceof Twig_Node_Print) {
+            return $this->escapePrintNode($node, $env, $this->needEscaping($env));
+        }
+
+        if ($node instanceof Twig_Node_AutoEscape || $node instanceof Twig_Node_Block) {
+            array_pop($this->statusStack);
+        } elseif ($node instanceof Twig_Node_BlockReference) {
+            $this->blocks[$node->getAttribute('name')] = $this->needEscaping($env);
+        }
+
+        return $node;
+    }
+
+    protected function escapePrintNode(Twig_Node_Print $node, Twig_Environment $env, $type)
+    {
+        if (false === $type) {
+            return $node;
+        }
+
+        $expression = $node->getNode('expr');
+
+        if ($this->isSafeFor($type, $expression, $env)) {
+            return $node;
+        }
+
+        $class = get_class($node);
+
+        return new $class(
+            $this->getEscaperFilter($type, $expression),
+            $node->getLine()
+        );
+    }
+
+    protected function preEscapeFilterNode(Twig_Node_Expression_Filter $filter, Twig_Environment $env)
+    {
+        $name = $filter->getNode('filter')->getAttribute('value');
+
+        $type = $env->getFilter($name)->getPreEscape();
+        if (null === $type) {
+            return $filter;
+        }
+
+        $node = $filter->getNode('node');
+        if ($this->isSafeFor($type, $node, $env)) {
+            return $filter;
+        }
+
+        $filter->setNode('node', $this->getEscaperFilter($type, $node));
+
+        return $filter;
+    }
+
+    protected function isSafeFor($type, Twig_NodeInterface $expression, $env)
+    {
+        $safe = $this->safeAnalysis->getSafe($expression);
+
+        if (null === $safe) {
+            if (null === $this->traverser) {
+                $this->traverser = new Twig_NodeTraverser($env, array($this->safeAnalysis));
+            }
+
+            $this->safeAnalysis->setSafeVars($this->safeVars);
+
+            $this->traverser->traverse($expression);
+            $safe = $this->safeAnalysis->getSafe($expression);
+        }
+
+        return in_array($type, $safe) || in_array('all', $safe);
+    }
+
+    protected function needEscaping(Twig_Environment $env)
+    {
+        if (count($this->statusStack)) {
+            return $this->statusStack[count($this->statusStack) - 1];
+        }
+
+        return $this->defaultStrategy ? $this->defaultStrategy : false;
+    }
+
+    protected function getEscaperFilter($type, Twig_NodeInterface $node)
+    {
+        $line = $node->getLine();
+        $name = new Twig_Node_Expression_Constant('escape', $line);
+        $args = new Twig_Node(array(new Twig_Node_Expression_Constant((string) $type, $line), new Twig_Node_Expression_Constant(null, $line), new Twig_Node_Expression_Constant(true, $line)));
+
+        return new Twig_Node_Expression_Filter($node, $name, $args, $line);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return 0;
+    }
+}
diff --git a/inc/Twig/NodeVisitor/Optimizer.php b/inc/Twig/NodeVisitor/Optimizer.php
new file mode 100644
index 00000000..a254def7
--- /dev/null
+++ b/inc/Twig/NodeVisitor/Optimizer.php
@@ -0,0 +1,246 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) 2010 Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Twig_NodeVisitor_Optimizer tries to optimizes the AST.
+ *
+ * This visitor is always the last registered one.
+ *
+ * You can configure which optimizations you want to activate via the
+ * optimizer mode.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class Twig_NodeVisitor_Optimizer implements Twig_NodeVisitorInterface
+{
+    const OPTIMIZE_ALL         = -1;
+    const OPTIMIZE_NONE        = 0;
+    const OPTIMIZE_FOR         = 2;
+    const OPTIMIZE_RAW_FILTER  = 4;
+    const OPTIMIZE_VAR_ACCESS  = 8;
+
+    protected $loops = array();
+    protected $optimizers;
+    protected $prependedNodes = array();
+    protected $inABody = false;
+
+    /**
+     * Constructor.
+     *
+     * @param integer $optimizers The optimizer mode
+     */
+    public function __construct($optimizers = -1)
+    {
+        if (!is_int($optimizers) || $optimizers > 2) {
+            throw new InvalidArgumentException(sprintf('Optimizer mode "%s" is not valid.', $optimizers));
+        }
+
+        $this->optimizers = $optimizers;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function enterNode(Twig_NodeInterface $node, Twig_Environment $env)
+    {
+        if (self::OPTIMIZE_FOR === (self::OPTIMIZE_FOR & $this->optimizers)) {
+            $this->enterOptimizeFor($node, $env);
+        }
+
+        if (!version_compare(phpversion(), '5.4.0RC1', '>=') && self::OPTIMIZE_VAR_ACCESS === (self::OPTIMIZE_VAR_ACCESS & $this->optimizers) && !$env->isStrictVariables() && !$env->hasExtension('sandbox')) {
+            if ($this->inABody) {
+                if (!$node instanceof Twig_Node_Expression) {
+                    if (get_class($node) !== 'Twig_Node') {
+                        array_unshift($this->prependedNodes, array());
+                    }
+                } else {
+                    $node = $this->optimizeVariables($node, $env);
+                }
+            } elseif ($node instanceof Twig_Node_Body) {
+                $this->inABody = true;
+            }
+        }
+
+        return $node;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function leaveNode(Twig_NodeInterface $node, Twig_Environment $env)
+    {
+        $expression = $node instanceof Twig_Node_Expression;
+
+        if (self::OPTIMIZE_FOR === (self::OPTIMIZE_FOR & $this->optimizers)) {
+            $this->leaveOptimizeFor($node, $env);
+        }
+
+        if (self::OPTIMIZE_RAW_FILTER === (self::OPTIMIZE_RAW_FILTER & $this->optimizers)) {
+            $node = $this->optimizeRawFilter($node, $env);
+        }
+
+        $node = $this->optimizePrintNode($node, $env);
+
+        if (self::OPTIMIZE_VAR_ACCESS === (self::OPTIMIZE_VAR_ACCESS & $this->optimizers) && !$env->isStrictVariables() && !$env->hasExtension('sandbox')) {
+            if ($node instanceof Twig_Node_Body) {
+                $this->inABody = false;
+            } elseif ($this->inABody) {
+                if (!$expression && get_class($node) !== 'Twig_Node' && $prependedNodes = array_shift($this->prependedNodes)) {
+                    $nodes = array();
+                    foreach (array_unique($prependedNodes) as $name) {
+                        $nodes[] = new Twig_Node_SetTemp($name, $node->getLine());
+                    }
+
+                    $nodes[] = $node;
+                    $node = new Twig_Node($nodes);
+                }
+            }
+        }
+
+        return $node;
+    }
+
+    protected function optimizeVariables($node, $env)
+    {
+        if ('Twig_Node_Expression_Name' === get_class($node) && $node->isSimple()) {
+            $this->prependedNodes[0][] = $node->getAttribute('name');
+
+            return new Twig_Node_Expression_TempName($node->getAttribute('name'), $node->getLine());
+        }
+
+        return $node;
+    }
+
+    /**
+     * Optimizes print nodes.
+     *
+     * It replaces:
+     *
+     *   * "echo $this->render(Parent)Block()" with "$this->display(Parent)Block()"
+     *
+     * @param Twig_NodeInterface $node A Node
+     * @param Twig_Environment   $env  The current Twig environment
+     */
+    protected function optimizePrintNode($node, $env)
+    {
+        if (!$node instanceof Twig_Node_Print) {
+            return $node;
+        }
+
+        if (
+            $node->getNode('expr') instanceof Twig_Node_Expression_BlockReference ||
+            $node->getNode('expr') instanceof Twig_Node_Expression_Parent
+        ) {
+            $node->getNode('expr')->setAttribute('output', true);
+
+            return $node->getNode('expr');
+        }
+
+        return $node;
+    }
+
+    /**
+     * Removes "raw" filters.
+     *
+     * @param Twig_NodeInterface $node A Node
+     * @param Twig_Environment   $env  The current Twig environment
+     */
+    protected function optimizeRawFilter($node, $env)
+    {
+        if ($node instanceof Twig_Node_Expression_Filter && 'raw' == $node->getNode('filter')->getAttribute('value')) {
+            return $node->getNode('node');
+        }
+
+        return $node;
+    }
+
+    /**
+     * Optimizes "for" tag by removing the "loop" variable creation whenever possible.
+     *
+     * @param Twig_NodeInterface $node A Node
+     * @param Twig_Environment   $env  The current Twig environment
+     */
+    protected function enterOptimizeFor($node, $env)
+    {
+        if ($node instanceof Twig_Node_For) {
+            // disable the loop variable by default
+            $node->setAttribute('with_loop', false);
+            array_unshift($this->loops, $node);
+        } elseif (!$this->loops) {
+            // we are outside a loop
+            return;
+        }
+
+        // when do we need to add the loop variable back?
+
+        // the loop variable is referenced for the current loop
+        elseif ($node instanceof Twig_Node_Expression_Name && 'loop' === $node->getAttribute('name')) {
+            $this->addLoopToCurrent();
+        }
+
+        // block reference
+        elseif ($node instanceof Twig_Node_BlockReference || $node instanceof Twig_Node_Expression_BlockReference) {
+            $this->addLoopToCurrent();
+        }
+
+        // include without the only attribute
+        elseif ($node instanceof Twig_Node_Include && !$node->getAttribute('only')) {
+            $this->addLoopToAll();
+        }
+
+        // the loop variable is referenced via an attribute
+        elseif ($node instanceof Twig_Node_Expression_GetAttr
+            && (!$node->getNode('attribute') instanceof Twig_Node_Expression_Constant
+                || 'parent' === $node->getNode('attribute')->getAttribute('value')
+               )
+            && (true === $this->loops[0]->getAttribute('with_loop')
+                || ($node->getNode('node') instanceof Twig_Node_Expression_Name
+                    && 'loop' === $node->getNode('node')->getAttribute('name')
+                   )
+               )
+        ) {
+            $this->addLoopToAll();
+        }
+    }
+
+    /**
+     * Optimizes "for" tag by removing the "loop" variable creation whenever possible.
+     *
+     * @param Twig_NodeInterface $node A Node
+     * @param Twig_Environment   $env  The current Twig environment
+     */
+    protected function leaveOptimizeFor($node, $env)
+    {
+        if ($node instanceof Twig_Node_For) {
+            array_shift($this->loops);
+        }
+    }
+
+    protected function addLoopToCurrent()
+    {
+        $this->loops[0]->setAttribute('with_loop', true);
+    }
+
+    protected function addLoopToAll()
+    {
+        foreach ($this->loops as $loop) {
+            $loop->setAttribute('with_loop', true);
+        }
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return 255;
+    }
+}
diff --git a/inc/Twig/NodeVisitor/SafeAnalysis.php b/inc/Twig/NodeVisitor/SafeAnalysis.php
new file mode 100644
index 00000000..c4bbd812
--- /dev/null
+++ b/inc/Twig/NodeVisitor/SafeAnalysis.php
@@ -0,0 +1,131 @@
+<?php
+
+class Twig_NodeVisitor_SafeAnalysis implements Twig_NodeVisitorInterface
+{
+    protected $data = array();
+    protected $safeVars = array();
+
+    public function setSafeVars($safeVars)
+    {
+        $this->safeVars = $safeVars;
+    }
+
+    public function getSafe(Twig_NodeInterface $node)
+    {
+        $hash = spl_object_hash($node);
+        if (isset($this->data[$hash])) {
+            foreach ($this->data[$hash] as $bucket) {
+                if ($bucket['key'] === $node) {
+                    return $bucket['value'];
+                }
+            }
+        }
+    }
+
+    protected function setSafe(Twig_NodeInterface $node, array $safe)
+    {
+        $hash = spl_object_hash($node);
+        if (isset($this->data[$hash])) {
+            foreach ($this->data[$hash] as &$bucket) {
+                if ($bucket['key'] === $node) {
+                    $bucket['value'] = $safe;
+
+                    return;
+                }
+            }
+        }
+        $this->data[$hash][] = array(
+            'key' => $node,
+            'value' => $safe,
+        );
+    }
+
+    public function enterNode(Twig_NodeInterface $node, Twig_Environment $env)
+    {
+        return $node;
+    }
+
+    public function leaveNode(Twig_NodeInterface $node, Twig_Environment $env)
+    {
+        if ($node instanceof Twig_Node_Expression_Constant) {
+            // constants are marked safe for all
+            $this->setSafe($node, array('all'));
+        } elseif ($node instanceof Twig_Node_Expression_BlockReference) {
+            // blocks are safe by definition
+            $this->setSafe($node, array('all'));
+        } elseif ($node instanceof Twig_Node_Expression_Parent) {
+            // parent block is safe by definition
+            $this->setSafe($node, array('all'));
+        } elseif ($node instanceof Twig_Node_Expression_Conditional) {
+            // intersect safeness of both operands
+            $safe = $this->intersectSafe($this->getSafe($node->getNode('expr2')), $this->getSafe($node->getNode('expr3')));
+            $this->setSafe($node, $safe);
+        } elseif ($node instanceof Twig_Node_Expression_Filter) {
+            // filter expression is safe when the filter is safe
+            $name = $node->getNode('filter')->getAttribute('value');
+            $args = $node->getNode('arguments');
+            if (false !== $filter = $env->getFilter($name)) {
+                $safe = $filter->getSafe($args);
+                if (null === $safe) {
+                    $safe = $this->intersectSafe($this->getSafe($node->getNode('node')), $filter->getPreservesSafety());
+                }
+                $this->setSafe($node, $safe);
+            } else {
+                $this->setSafe($node, array());
+            }
+        } elseif ($node instanceof Twig_Node_Expression_Function) {
+            // function expression is safe when the function is safe
+            $name = $node->getAttribute('name');
+            $args = $node->getNode('arguments');
+            $function = $env->getFunction($name);
+            if (false !== $function) {
+                $this->setSafe($node, $function->getSafe($args));
+            } else {
+                $this->setSafe($node, array());
+            }
+        } elseif ($node instanceof Twig_Node_Expression_MethodCall) {
+            if ($node->getAttribute('safe')) {
+                $this->setSafe($node, array('all'));
+            } else {
+                $this->setSafe($node, array());
+            }
+        } elseif ($node instanceof Twig_Node_Expression_GetAttr && $node->getNode('node') instanceof Twig_Node_Expression_Name) {
+            $name = $node->getNode('node')->getAttribute('name');
+            // attributes on template instances are safe
+            if ('_self' == $name || in_array($name, $this->safeVars)) {
+                $this->setSafe($node, array('all'));
+            } else {
+                $this->setSafe($node, array());
+            }
+        } else {
+            $this->setSafe($node, array());
+        }
+
+        return $node;
+    }
+
+    protected function intersectSafe(array $a = null, array $b = null)
+    {
+        if (null === $a || null === $b) {
+            return array();
+        }
+
+        if (in_array('all', $a)) {
+            return $b;
+        }
+
+        if (in_array('all', $b)) {
+            return $a;
+        }
+
+        return array_intersect($a, $b);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return 0;
+    }
+}
diff --git a/inc/Twig/NodeVisitor/Sandbox.php b/inc/Twig/NodeVisitor/Sandbox.php
new file mode 100644
index 00000000..fb27045b
--- /dev/null
+++ b/inc/Twig/NodeVisitor/Sandbox.php
@@ -0,0 +1,92 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) 2009 Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Twig_NodeVisitor_Sandbox implements sandboxing.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class Twig_NodeVisitor_Sandbox implements Twig_NodeVisitorInterface
+{
+    protected $inAModule = false;
+    protected $tags;
+    protected $filters;
+    protected $functions;
+
+    /**
+     * Called before child nodes are visited.
+     *
+     * @param Twig_NodeInterface $node The node to visit
+     * @param Twig_Environment   $env  The Twig environment instance
+     *
+     * @return Twig_NodeInterface The modified node
+     */
+    public function enterNode(Twig_NodeInterface $node, Twig_Environment $env)
+    {
+        if ($node instanceof Twig_Node_Module) {
+            $this->inAModule = true;
+            $this->tags = array();
+            $this->filters = array();
+            $this->functions = array();
+
+            return $node;
+        } elseif ($this->inAModule) {
+            // look for tags
+            if ($node->getNodeTag()) {
+                $this->tags[] = $node->getNodeTag();
+            }
+
+            // look for filters
+            if ($node instanceof Twig_Node_Expression_Filter) {
+                $this->filters[] = $node->getNode('filter')->getAttribute('value');
+            }
+
+            // look for functions
+            if ($node instanceof Twig_Node_Expression_Function) {
+                $this->functions[] = $node->getAttribute('name');
+            }
+
+            // wrap print to check __toString() calls
+            if ($node instanceof Twig_Node_Print) {
+                return new Twig_Node_SandboxedPrint($node->getNode('expr'), $node->getLine(), $node->getNodeTag());
+            }
+        }
+
+        return $node;
+    }
+
+    /**
+     * Called after child nodes are visited.
+     *
+     * @param Twig_NodeInterface $node The node to visit
+     * @param Twig_Environment   $env  The Twig environment instance
+     *
+     * @return Twig_NodeInterface The modified node
+     */
+    public function leaveNode(Twig_NodeInterface $node, Twig_Environment $env)
+    {
+        if ($node instanceof Twig_Node_Module) {
+            $this->inAModule = false;
+
+            return new Twig_Node_SandboxedModule($node, array_unique($this->filters), array_unique($this->tags), array_unique($this->functions));
+        }
+
+        return $node;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getPriority()
+    {
+        return 0;
+    }
+}