fix-#789: abstract shouldn't be inherited in EmbeddedDocument

docs/changelog.rst

@@ -5,6 +5,7 @@ Changelog
 
 Changes in 0.9.X - DEV
 ======================
+- abstract shouldn't be inherited in EmbeddedDocument # 789
 - Allow specifying the '_cls' as a field for indexes #397
 - Stop ensure_indexes running on a secondaries unless connection is through mongos #746
 - Not overriding default values when loading a subset of fields #399

mongoengine/base/metaclasses.py

@@ -46,8 +46,9 @@ class DocumentMetaclass(type):
                 elif hasattr(base, '_meta'):
                     meta.merge(base._meta)
             attrs['_meta'] = meta
+            attrs['_meta']['abstract'] = False  # 789: EmbeddedDocument shouldn't inherit abstract
 
-        if '_meta' in attrs and attrs['_meta'].get('allow_inheritance', ALLOW_INHERITANCE):
+        if attrs['_meta'].get('allow_inheritance', ALLOW_INHERITANCE):
             StringField = _import_class('StringField')
             attrs['_cls'] = StringField()
 

tests/document/inheritance.py

@@ -397,6 +397,16 @@ class InheritanceTest(unittest.TestCase):
                 meta = {'abstract': True}
         self.assertRaises(ValueError, create_bad_abstract)
 
+    def test_abstract_embedded_documents(self):
+        # 789: EmbeddedDocument shouldn't inherit abstract
+        class A(EmbeddedDocument):
+            meta = {"abstract": True}
+
+        class B(A):
+            pass
+
+        self.assertFalse(B._meta["abstract"])
+
     def test_inherited_collections(self):
         """Ensure that subclassed documents don't override parents'
         collections