feature #12022 [HttpKernel] Extract method to instantiate controller …

…in ControllerResolver (danharper)

This PR was merged into the 2.6-dev branch.

Discussion
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[HttpKernel] Extract method to instantiate controller in ControllerResolver

Replaces #10814 to merge into `master` instead of `2.3`.

---

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

Currently it's required to duplicate the entirety of the `getController()` and `createController()` methods just to replace the call to `new` (e.g. with container resolution, instead).

Now it's possible to just override the `instantiateController()` method.

Commits
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88274df [HttpKernel] Extract method to make callable controller in ControllerResolver

src/Symfony/Component/HttpKernel/Controller/ControllerResolver.php

@@ -71,7 +71,7 @@ public function getController(Request $request)
 
         if (false === strpos($controller, ':')) {
             if (method_exists($controller, '__invoke')) {
-                return new $controller();
+                return $this->instantiateController($controller);
             } elseif (function_exists($controller)) {
                 return $controller;
             }
@@ -153,6 +153,18 @@ protected function createController($controller)
             throw new \InvalidArgumentException(sprintf('Class "%s" does not exist.', $class));
         }
 
-        return array(new $class(), $method);
+        return array($this->instantiateController($class), $method);
+    }
+
+    /**
+     * Returns an instantiated controller
+     *
+     * @param string $class A class name
+     *
+     * @return object
+     */
+    protected function instantiateController($class)
+    {
+        return new $class();
     }
 }