minor #14303 [Config][cache factory] check type of callback argument. (aitboudad)

This PR was merged into the 2.7 branch.

Discussion
----------

[Config][cache factory] check type of callback argument.

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Fixed tickets  | #14178
| Tests pass?   | yes
| License       | MIT

/cc @mpdude

Commits
-------

11f798c [Config][cache factory] check type of callback argument.

src/Symfony/Component/Config/ConfigCacheFactory.php

@@ -37,8 +37,11 @@ class ConfigCacheFactory implements ConfigCacheFactoryInterface
      */
     public function cache($file, $callback)
     {
-        $cache = new ConfigCache($file, $this->debug);
+        if (!is_callable($callback)) {
+            throw new \InvalidArgumentException(sprintf('Invalid type for callback argument. Expected callable, but got "%s".', gettype($callback)));
+        }
 
+        $cache = new ConfigCache($file, $this->debug);
         if (!$cache->isFresh()) {
             call_user_func($callback, $cache);
         }

src/Symfony/Component/Config/Tests/ConfigCacheFactoryTest.php

@@ -0,0 +1,28 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Config\Tests;
+
+use Symfony\Component\Config\ConfigCacheFactory;
+
+class ConfigCacheFactoryTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @expectedException \InvalidArgumentException
+     * @expectedExceptionMessage Invalid type for callback argument. Expected callable, but got "object".
+     */
+    public function testCachWithInvalidCallback()
+    {
+        $cacheFactory = new ConfigCacheFactory(true);
+
+        $cacheFactory->cache('file', new \stdClass());
+    }
+}