diff --git a/DependencyInjection/Configuration.php b/DependencyInjection/Configuration.php
index 874f51e..dd41b09 100644
--- a/DependencyInjection/Configuration.php
+++ b/DependencyInjection/Configuration.php
@@ -182,7 +182,7 @@ class Configuration implements ConfigurationInterface
                 ->treatNullLike(array())
                 // BC - Renaming 'mappings' node to 'properties'
                 ->beforeNormalization()
-                ->ifTrue(function($v) { return isset($v['mappings']); })
+                ->ifTrue(function($v) { return array_key_exists('mappings', $v); })
                 ->then(function($v) {
                     $v['properties'] = $v['mappings'];
                     unset($v['mappings']);
@@ -213,7 +213,7 @@ class Configuration implements ConfigurationInterface
                     foreach ($v['dynamic_templates'] as $key => $type) {
                         if (is_int($key)) {
                             $dt[] = $type;
-                        } else { 
+                        } else {
                             $dt[][$key] = $type;
                         }
                     }
diff --git a/Tests/Functional/ConfigurationManagerTest.php b/Tests/Functional/ConfigurationManagerTest.php
index 6fdc1d7..7ef02c5 100644
--- a/Tests/Functional/ConfigurationManagerTest.php
+++ b/Tests/Functional/ConfigurationManagerTest.php
@@ -26,7 +26,7 @@ class ConfigurationManagerTest extends WebTestCase
         $index = $manager->getIndexConfiguration('index');
 
         $this->assertEquals('index', $index->getName());
-        $this->assertCount(2, $index->getTypes());
+        $this->assertGreaterThanOrEqual(2, count($index->getTypes()));
         $this->assertInstanceOf('FOS\\ElasticaBundle\\Configuration\\TypeConfig', $index->getType('type'));
         $this->assertInstanceOf('FOS\\ElasticaBundle\\Configuration\\TypeConfig', $index->getType('parent'));
     }
diff --git a/Tests/Functional/app/Basic/config.yml b/Tests/Functional/app/Basic/config.yml
index 607e3cc..9feed34 100644
--- a/Tests/Functional/app/Basic/config.yml
+++ b/Tests/Functional/app/Basic/config.yml
@@ -83,3 +83,5 @@ fos_elastica:
                         type: "parent"
                         property: "parent"
                         identifier: "id"
+                null_mappings:
+                    mappings: ~