Fix "embed" support when used from "template_from_string"

CHANGELOG

@@ -1,5 +1,6 @@
 * 1.38.0 (2019-XX-XX)
 
+ * fixed "embed" support when used from "template_from_string"
  * added the possibility to pass a TemplateWrapper to Twig\Environment::load()
  * improved the performance of the sandbox
  * added a spaceless filter

src/Environment.php

@@ -351,7 +351,7 @@ public function getTemplateClass($name, $index = null)
     {
         $key = $this->getLoader()->getCacheKey($name).$this->optionsHash;
 
-        return $this->templateClassPrefix.hash('sha256', $key).(null === $index ? '' : '_'.$index);
+        return $this->templateClassPrefix.hash('sha256', $key).(null === $index ? '' : '___'.$index);
     }
 
     /**
@@ -443,9 +443,17 @@ public function load($name)
      */
     public function loadTemplate($name, $index = null)
     {
-        $cls = $mainCls = $this->getTemplateClass($name);
+        return $this->loadClass($this->getTemplateClass($name), $name, $index);
+    }
+
+    /**
+     * @internal
+     */
+    public function loadClass($cls, $name, $index = null)
+    {
+        $mainCls = $cls;
         if (null !== $index) {
-            $cls .= '_'.$index;
+            $cls .= '___'.$index;
         }
 
         if (isset($this->loadedTemplates[$cls])) {
@@ -491,7 +499,7 @@ public function loadTemplate($name, $index = null)
             }
 
             if (!class_exists($cls, false)) {
-                throw new RuntimeError(sprintf('Failed to load Twig template "%s", index "%s": cache is corrupted.', $name, $index), -1, $source);
+                throw new RuntimeError(sprintf('Failed to load Twig template "%s", index "%s": cache might be corrupted.', $name, $index), -1, $source);
             }
         }
 

src/Template.php

@@ -351,6 +351,15 @@ protected function loadTemplate($template, $templateName = null, $line = null, $
                 return $template;
             }
 
+            if ($template === $this->getTemplateName()) {
+                $class = get_class($this);
+                if (false !== $pos = strrpos($class, '___', -1)) {
+                    $class = substr($class, 0, $pos);
+                }
+
+                return $this->env->loadClass($class, $template, $index);
+            }
+
             return $this->env->loadTemplate($template, $index);
         } catch (Error $e) {
             if (!$e->getSourceContext()) {

test/Twig/Tests/Fixtures/functions/include_template_from_string.test

@@ -0,0 +1,11 @@
+--TEST--
+"template_from_string" function works in an "include"
+--TEMPLATE--
+{% set embed = '{% embed "embed.twig" %}{% endembed %}' %}
+{{ include(template_from_string(embed)) }}
+--TEMPLATE(embed.twig)--
+Cool
+--DATA--
+return []
+--EXPECT--
+Cool