Add custom twig loader to workaround cache issue

DependencyInjection/Compiler/ThemeCompilerPass.php

@@ -23,9 +23,34 @@ public function process(ContainerBuilder $container)
 
         $container->setAlias('templating.cache_warmer.template_paths', 'liip_theme.templating.cache_warmer.template_paths');
 
+        if (true === $container->hasDefinition('twig')) {
+            $twigLoader = $container->findDefinition('twig.loader');
+            $aliasedTo = $this->resolveAlias('twig.loader', $container);
+            if ($aliasedTo == 'twig.loader.chain') {
+                $methodCalls = $twigLoader->getMethodCalls();
+                foreach($methodCalls as $index => $methodCall) {
+                    if ($methodCall[0] == 'addLoader' && (string) $methodCall[1][0] == 'twig.loader.filesystem') {
+                        $methodCalls[$index] = array($methodCall[0], array(new Reference('liip_theme.twig.loader.filesystem')));
+                    }
+                }
+                $twigLoader->setMethodCalls($methodCalls);
+            } elseif ($aliasedTo == 'twig.loader.filesystem') {
+                $container->setAlias('twig.loader.filesystem', 'liip_theme.twig.loader.filesystem');
+            }
+        }
+
         if (!$container->getParameter('liip_theme.cache_warming')) {
             $container->getDefinition('liip_theme.templating.cache_warmer.template_paths')
                 ->replaceArgument(2, null);
         }
     }
+
+    public function resolveContainerAlias($id, ContainerBuilder $container) {
+        while($container->hasAlias($id)) {
+            $id = $container->getAlias($id);
+        }
+
+        return $id;
+    }
+
 }

Loader/FilesystemLoader.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace Liip\ThemeBundle\Loader;
+
+
+use Liip\ThemeBundle\ActiveTheme;
+use Symfony\Bundle\TwigBundle\Loader\FilesystemLoader as BaseFilesystemLoader;
+use Symfony\Component\Config\FileLocatorInterface;
+use Symfony\Component\Templating\TemplateNameParserInterface;
+
+class FilesystemLoader extends BaseFilesystemLoader
+{
+    public function __construct(FileLocatorInterface $locator, TemplateNameParserInterface $parser, ActiveTheme $activeTheme)
+    {
+        $this->activeTheme = $activeTheme;
+        parent::__construct($locator, $parser);
+    }
+
+    protected function findTemplate($template)
+    {
+        $logicalName = (string)$template;
+        $cacheKey = $logicalName;
+        if($theme = $this->activeTheme->getName()) {
+            $cacheKey = $cacheKey . '|' . $theme;
+        }
+
+        if(isset($this->cache[$cacheKey])) {
+            return $this->cache[$cacheKey];
+        }
+
+        $file = parent::findTemplate($template);
+
+        unset($this->cache[$logicalName]);
+        $this->cache[$cacheKey] = $file;
+
+        return $file;
+    }
+
+}

Resources/config/templating.xml

@@ -9,6 +9,7 @@
         <parameter key="liip_theme.active_theme.class">Liip\ThemeBundle\ActiveTheme</parameter>
         <parameter key="liip_theme.cache_warmer.class">Liip\ThemeBundle\CacheWarmer\TemplatePathsCacheWarmer</parameter>
         <parameter key="liip_theme.theme_auto_detect.class">Liip\ThemeBundle\Helper\DeviceDetection</parameter>
+        <parameter key="liip_theme.twig.loader.filesystem.class">Liip\ThemeBundle\Loader\FilesystemLoader</parameter>
     </parameters>
 
     <services>
@@ -25,6 +26,12 @@
             <argument type="service" id="liip_theme.active_theme" />
         </service>
 
+        <service id="liip_theme.twig.loader.filesystem" class="%liip_theme.twig.loader.filesystem.class%" public="false">
+            <argument type="service" id="templating.locator" />
+            <argument type="service" id="templating.name_parser" />
+            <argument type="service" id="liip_theme.active_theme" />
+        </service>
+
         <service id="liip_theme.file_locator" class="%liip_theme.file_locator.class%" public="false">
             <argument type="service" id="kernel" />
             <argument type="service" id="liip_theme.active_theme" />