1 files changed, 139 insertions, 0 deletions

diff --git a/inc/Twig/Loader/Chain.php b/inc/Twig/Loader/Chain.php
new file mode 100644
index 00000000..1f1cf065
--- /dev/null
+++ b/inc/Twig/Loader/Chain.php
@@ -0,0 +1,139 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) 2011 Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Loads templates from other loaders.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class Twig_Loader_Chain implements Twig_LoaderInterface, Twig_ExistsLoaderInterface
+{
+    private $hasSourceCache = array();
+    protected $loaders;
+
+    /**
+     * Constructor.
+     *
+     * @param Twig_LoaderInterface[] $loaders An array of loader instances
+     */
+    public function __construct(array $loaders = array())
+    {
+        $this->loaders = array();
+        foreach ($loaders as $loader) {
+            $this->addLoader($loader);
+        }
+    }
+
+    /**
+     * Adds a loader instance.
+     *
+     * @param Twig_LoaderInterface $loader A Loader instance
+     */
+    public function addLoader(Twig_LoaderInterface $loader)
+    {
+        $this->loaders[] = $loader;
+        $this->hasSourceCache = array();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getSource($name)
+    {
+        $exceptions = array();
+        foreach ($this->loaders as $loader) {
+            if ($loader instanceof Twig_ExistsLoaderInterface && !$loader->exists($name)) {
+                continue;
+            }
+
+            try {
+                return $loader->getSource($name);
+            } catch (Twig_Error_Loader $e) {
+                $exceptions[] = $e->getMessage();
+            }
+        }
+
+        throw new Twig_Error_Loader(sprintf('Template "%s" is not defined (%s).', $name, implode(', ', $exceptions)));
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function exists($name)
+    {
+        $name = (string) $name;
+
+        if (isset($this->hasSourceCache[$name])) {
+            return $this->hasSourceCache[$name];
+        }
+
+        foreach ($this->loaders as $loader) {
+            if ($loader instanceof Twig_ExistsLoaderInterface) {
+                if ($loader->exists($name)) {
+                    return $this->hasSourceCache[$name] = true;
+                }
+
+                continue;
+            }
+
+            try {
+                $loader->getSource($name);
+
+                return $this->hasSourceCache[$name] = true;
+            } catch (Twig_Error_Loader $e) {
+            }
+        }
+
+        return $this->hasSourceCache[$name] = false;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getCacheKey($name)
+    {
+        $exceptions = array();
+        foreach ($this->loaders as $loader) {
+            if ($loader instanceof Twig_ExistsLoaderInterface && !$loader->exists($name)) {
+                continue;
+            }
+
+            try {
+                return $loader->getCacheKey($name);
+            } catch (Twig_Error_Loader $e) {
+                $exceptions[] = get_class($loader).': '.$e->getMessage();
+            }
+        }
+
+        throw new Twig_Error_Loader(sprintf('Template "%s" is not defined (%s).', $name, implode(' ', $exceptions)));
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function isFresh($name, $time)
+    {
+        $exceptions = array();
+        foreach ($this->loaders as $loader) {
+            if ($loader instanceof Twig_ExistsLoaderInterface && !$loader->exists($name)) {
+                continue;
+            }
+
+            try {
+                return $loader->isFresh($name, $time);
+            } catch (Twig_Error_Loader $e) {
+                $exceptions[] = get_class($loader).': '.$e->getMessage();
+            }
+        }
+
+        throw new Twig_Error_Loader(sprintf('Template "%s" is not defined (%s).', $name, implode(' ', $exceptions)));
+    }
+}