--- /dev/null
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) 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.
+ *
+ * @final
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class Twig_NodeVisitor_Optimizer extends Twig_BaseNodeVisitor
+{
+ 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 $loopsTargets = array();
+ protected $optimizers;
+ protected $prependedNodes = array();
+ protected $inABody = false;
+
+ /**
+ * @param int $optimizers The optimizer mode
+ */
+ public function __construct($optimizers = -1)
+ {
+ if (!is_int($optimizers) || $optimizers > (self::OPTIMIZE_FOR | self::OPTIMIZE_RAW_FILTER | self::OPTIMIZE_VAR_ACCESS)) {
+ throw new InvalidArgumentException(sprintf('Optimizer mode "%s" is not valid.', $optimizers));
+ }
+
+ $this->optimizers = $optimizers;
+ }
+
+ protected function doEnterNode(Twig_Node $node, Twig_Environment $env)
+ {
+ if (self::OPTIMIZE_FOR === (self::OPTIMIZE_FOR & $this->optimizers)) {
+ $this->enterOptimizeFor($node, $env);
+ }
+
+ if (PHP_VERSION_ID < 50400 && self::OPTIMIZE_VAR_ACCESS === (self::OPTIMIZE_VAR_ACCESS & $this->optimizers) && !$env->isStrictVariables() && !$env->hasExtension('Twig_Extension_Sandbox')) {
+ if ($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;
+ }
+
+ protected function doLeaveNode(Twig_Node $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() && !$env->hasExtension('Twig_Extension_Sandbox')) {
+ if ($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->getTemplateLine());
+ }
+
+ $nodes[] = $node;
+ $node = new Twig_Node($nodes);
+ }
+ }
+ }
+
+ return $node;
+ }
+
+ protected function optimizeVariables(Twig_NodeInterface $node, Twig_Environment $env)
+ {
+ if ('Twig_Node_Expression_Name' === get_class($node) && $node->isSimple()) {
+ $this->prependedNodes[0][] = $node->getAttribute('name');
+
+ return new Twig_Node_Expression_TempName($node->getAttribute('name'), $node->getTemplateLine());
+ }
+
+ return $node;
+ }
+
+ /**
+ * Optimizes print nodes.
+ *
+ * It replaces:
+ *
+ * * "echo $this->render(Parent)Block()" with "$this->display(Parent)Block()"
+ *
+ * @return Twig_NodeInterface
+ */
+ protected function optimizePrintNode(Twig_NodeInterface $node, Twig_Environment $env)
+ {
+ if (!$node instanceof Twig_Node_Print) {
+ return $node;
+ }
+
+ $exprNode = $node->getNode('expr');
+ if (
+ $exprNode instanceof Twig_Node_Expression_BlockReference ||
+ $exprNode instanceof Twig_Node_Expression_Parent
+ ) {
+ $exprNode->setAttribute('output', true);
+
+ return $exprNode;
+ }
+
+ return $node;
+ }
+
+ /**
+ * Removes "raw" filters.
+ *
+ * @return Twig_NodeInterface
+ */
+ protected function optimizeRawFilter(Twig_NodeInterface $node, Twig_Environment $env)
+ {
+ if ($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.
+ */
+ protected function enterOptimizeFor(Twig_NodeInterface $node, Twig_Environment $env)
+ {
+ if ($node instanceof Twig_Node_For) {
+ // disable the loop variable by default
+ $node->setAttribute('with_loop', false);
+ array_unshift($this->loops, $node);
+ array_unshift($this->loopsTargets, $node->getNode('value_target')->getAttribute('name'));
+ array_unshift($this->loopsTargets, $node->getNode('key_target')->getAttribute('name'));
+ } elseif (!$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')) {
+ $node->setAttribute('always_defined', true);
+ $this->addLoopToCurrent();
+ }
+
+ // optimize access to loop targets
+ elseif ($node instanceof Twig_Node_Expression_Name && in_array($node->getAttribute('name'), $this->loopsTargets)) {
+ $node->setAttribute('always_defined', true);
+ }
+
+ // block reference
+ elseif ($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')) {
+ $this->addLoopToAll();
+ }
+
+ // include function without the with_context=false parameter
+ elseif ($node instanceof Twig_Node_Expression_Function
+ && 'include' === $node->getAttribute('name')
+ && (!$node->getNode('arguments')->hasNode('with_context')
+ || false !== $node->getNode('arguments')->getNode('with_context')->getAttribute('value')
+ )
+ ) {
+ $this->addLoopToAll();
+ }
+
+ // the loop variable is referenced via an attribute
+ elseif ($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.
+ */
+ protected function leaveOptimizeFor(Twig_NodeInterface $node, Twig_Environment $env)
+ {
+ if ($node instanceof Twig_Node_For) {
+ array_shift($this->loops);
+ array_shift($this->loopsTargets);
+ array_shift($this->loopsTargets);
+ }
+ }
+
+ protected function addLoopToCurrent()
+ {
+ $this->loops[0]->setAttribute('with_loop', true);
+ }
+
+ protected function addLoopToAll()
+ {
+ foreach ($this->loops as $loop) {
+ $loop->setAttribute('with_loop', true);
+ }
+ }
+
+ public function getPriority()
+ {
+ return 255;
+ }
+}
projects / yaffs-website / blobdiff