diff --git a/Config/Config.php b/Config/Config.php
index 6b34112..7862db3 100644
--- a/Config/Config.php
+++ b/Config/Config.php
@@ -41,7 +41,7 @@ public static function factory(array $param, $class = 'ConfigDefault')
             return new $class($param);
         } else {
             throw new \ErrorException(
-                'Config::factory() - could not instantiate ' . $class . ' - not in self::$whitelist'
+                'Config::factory() - could not instantiate ' . $class
             );
         }
     }
diff --git a/Config/ConfigEnv.php b/Config/ConfigEnv.php
index 4fdf8f7..f7733ed 100644
--- a/Config/ConfigEnv.php
+++ b/Config/ConfigEnv.php
@@ -63,7 +63,7 @@ private function mergeEnvironments($param)
                 $toMerge
             );
         } else {
-            $merged = $config->get($this->defaultEnv);
+            $merged = $config->get($this->defaultEnv, []);
         }
 
         $this->setByArray(
diff --git a/Test/BaseConfigTest.php b/Test/BaseConfigTest.php
index cd452c9..2ba9c68 100644
--- a/Test/BaseConfigTest.php
+++ b/Test/BaseConfigTest.php
@@ -34,7 +34,7 @@ public function setUp()
 
         $this->root = vfsStream::setup('configs');
         $this->configFile = vfsStream::newFile('default.yml')->at($this->root);
-        $this->configFile->setContent(TestData::getYamlConfigFile());
+        $this->configFile->setContent(TestData::getYamlImportConfigFile());
 
         $this->configImportFile = vfsStream::newFile('testimport.yml')->at($this->root);
         $this->configImportFile->setContent(TestData::getYamlImportFile());
diff --git a/Test/TestData.php b/Test/TestData.php
index c576435..05e7b88 100644
--- a/Test/TestData.php
+++ b/Test/TestData.php
@@ -15,6 +15,7 @@ class TestData
     public static function getYamlImportFile()
     {
         return <<<EOT
+---
 testkey_5:
     default: yaddayadda
     my_test: is testing hard
@@ -29,6 +30,38 @@ public static function getYamlImportFile()
     public static function getYamlConfigFile()
     {
         return <<<EOT
+---
+default:
+    testkey_4: 'default test'
+prod:
+    testkey_1: 'testvalue'
+    testkey_2:
+        - dummy1
+        - dummy2
+        - dummy3
+    testkey_3:
+        subkey_1: subvalue1
+        subkey_2: 123
+        subkey_3: ~
+
+stage: []
+test: []
+dev:
+    testkey_2:
+        - 25
+        - 69
+EOT;
+    }
+
+    /**
+     * provide yaml schema testdata
+     *
+     * @return string
+     */
+    public static function getYamlImportConfigFile()
+    {
+        return <<<EOT
+---
 imports:
     - { resource: 'vfs://configs/testimport.yml' }
 default:
@@ -64,6 +97,7 @@ public static function getYamlTimerConfigFile()
         $tomorrow = new \DateTime('tomorrow');
 
         return <<<EOT
+---
 timers:
     example_timer_config_1:
         interval:
diff --git a/Tests/Config/ConfigEnvTest.php b/Tests/Config/ConfigEnvTest.php
index 1f954b7..850333e 100644
--- a/Tests/Config/ConfigEnvTest.php
+++ b/Tests/Config/ConfigEnvTest.php
@@ -52,7 +52,7 @@ public function testFactoryProdWithoutFilecheck()
         // merged environments config
         $config = Config::factory(
             [
-                'file' => $this->getTestYaml(),
+                'file' => TestData::getYamlConfigFile(),
                 'filecheck' => false,
             ],
             'ConfigEnv'