diff --git a/cdist/test/cdist_type/__init__.py b/cdist/test/cdist_type/__init__.py
index e97ce7e6..79f824d3 100644
--- a/cdist/test/cdist_type/__init__.py
+++ b/cdist/test/cdist_type/__init__.py
@@ -146,3 +146,10 @@ class TypeTestCase(test.CdistTestCase):
         cdist_type = core.CdistType(base_path, '__without_boolean_parameters')
         self.assertEqual(cdist_type.boolean_parameters, [])
 
+    def test_with_parameter_defaults(self):
+        base_path = fixtures
+        cdist_type = core.CdistType(base_path, '__with_parameter_defaults')
+        self.assertTrue('optional1' in cdist_type.parameter_defaults)
+        self.assertFalse('optional2' in cdist_type.parameter_defaults)
+        self.assertEqual(cdist_type.parameter_defaults['optional1'], 'value1')
+
diff --git a/cdist/test/cdist_type/fixtures/__with_parameter_defaults/parameter/default/optional1 b/cdist/test/cdist_type/fixtures/__with_parameter_defaults/parameter/default/optional1
new file mode 100644
index 00000000..ef208405
--- /dev/null
+++ b/cdist/test/cdist_type/fixtures/__with_parameter_defaults/parameter/default/optional1
@@ -0,0 +1 @@
+value1
diff --git a/cdist/test/cdist_type/fixtures/__with_parameter_defaults/parameter/optional b/cdist/test/cdist_type/fixtures/__with_parameter_defaults/parameter/optional
new file mode 100644
index 00000000..8174d2a9
--- /dev/null
+++ b/cdist/test/cdist_type/fixtures/__with_parameter_defaults/parameter/optional
@@ -0,0 +1,2 @@
+optional1
+optional2
diff --git a/cdist/test/emulator/__init__.py b/cdist/test/emulator/__init__.py
index 9f6d7000..8c2dcd72 100644
--- a/cdist/test/emulator/__init__.py
+++ b/cdist/test/emulator/__init__.py
@@ -219,6 +219,21 @@ class ArgumentsTestCase(test.CdistTestCase):
         self.assertFalse('optional2' in cdist_object.parameters)
         self.assertEqual(cdist_object.parameters['optional1'], value)
 
+    def test_argument_defaults(self):
+        type_name = '__argument_defaults'
+        object_id = 'some-id'
+        value = 'value1'
+        argv = [type_name, object_id]
+        os.environ.update(self.env)
+        emu = emulator.Emulator(argv)
+        emu.run()
+
+        cdist_type = core.CdistType(self.local.type_path, type_name)
+        cdist_object = core.CdistObject(cdist_type, self.local.object_path, object_id)
+        self.assertTrue('optional1' in cdist_object.parameters)
+        self.assertFalse('optional2' in cdist_object.parameters)
+        self.assertEqual(cdist_object.parameters['optional1'], value)
+
 
 class StdinTestCase(test.CdistTestCase):
 
diff --git a/cdist/test/emulator/fixtures/conf/type/__argument_defaults/parameter/default/optional1 b/cdist/test/emulator/fixtures/conf/type/__argument_defaults/parameter/default/optional1
new file mode 100644
index 00000000..ef208405
--- /dev/null
+++ b/cdist/test/emulator/fixtures/conf/type/__argument_defaults/parameter/default/optional1
@@ -0,0 +1 @@
+value1
diff --git a/cdist/test/emulator/fixtures/conf/type/__argument_defaults/parameter/optional b/cdist/test/emulator/fixtures/conf/type/__argument_defaults/parameter/optional
new file mode 100644
index 00000000..8174d2a9
--- /dev/null
+++ b/cdist/test/emulator/fixtures/conf/type/__argument_defaults/parameter/optional
@@ -0,0 +1,2 @@
+optional1
+optional2