[DebugBundle] add tests for twig and for the bundle

Author: nicolas-grekas

VarDumper.php

@@ -33,12 +33,12 @@ public static function dump($var)
             };
         }
 
-        return call_user_func(self::$handler, $h);
+        return call_user_func(self::$handler, $var);
     }
 
     public static function setHandler($callable)
     {
-        if (!is_callable($callable, true)) {
+        if (null !== $callable && !is_callable($callable, true)) {
             throw new \InvalidArgumentException('Invalid PHP callback.');
         }
 

phpunit.xml.dist

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/4.1/phpunit.xsd"
+         backupGlobals="false"
+         colors="true"
+         bootstrap="vendor/autoload.php"
+>
+
+    <testsuites>
+        <testsuite name="Symfony VarDumper Component Test Suite">
+            <directory>./Tests/</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+        <whitelist>
+            <directory>./</directory>
+            <exclude>
+                <directory>./Tests</directory>
+                <directory>./Resources</directory>
+                <directory>./vendor</directory>
+            </exclude>
+        </whitelist>
+    </filter>
+</phpunit>