Fixed weakref being valid after reload (#374)

docs/changelog.rst

@@ -4,6 +4,7 @@ Changelog
 
 Changes in 0.8.3
 ================
+- Fixed weakref being valid after reload (#374)
 - Fixed queryset.get() respecting no_dereference (#373)
 - Added full_result kwarg to update (#380)
 

mongoengine/document.py

@@ -480,6 +480,7 @@ class Document(BaseDocument):
             value = [self._reload(key, v) for v in value]
             value = BaseList(value, self, key)
         elif isinstance(value, (EmbeddedDocument, DynamicEmbeddedDocument)):
+            value._instance = None
             value._changed_fields = []
         return value
 

tests/queryset/queryset.py

@@ -1613,6 +1613,32 @@ class QuerySetTest(unittest.TestCase):
         self.assertEqual(message.authors[1].name, "Ross")
         self.assertEqual(message.authors[2].name, "Adam")
 
+    def test_reload_embedded_docs_instance(self):
+
+        class SubDoc(EmbeddedDocument):
+            val = IntField()
+
+        class Doc(Document):
+            embedded = EmbeddedDocumentField(SubDoc)
+
+        doc = Doc(embedded=SubDoc(val=0)).save()
+        doc.reload()
+
+        self.assertEqual(doc.pk, doc.embedded._instance.pk)
+
+    def test_reload_list_embedded_docs_instance(self):
+
+        class SubDoc(EmbeddedDocument):
+            val = IntField()
+
+        class Doc(Document):
+            embedded = ListField(EmbeddedDocumentField(SubDoc))
+
+        doc = Doc(embedded=[SubDoc(val=0)]).save()
+        doc.reload()
+
+        self.assertEqual(doc.pk, doc.embedded[0]._instance.pk)
+
     def test_order_by(self):
         """Ensure that QuerySets may be ordered.
         """