use each modifier only with #1673

mongoengine/queryset/transform.py

@@ -344,8 +344,6 @@ def update(_doc_cls=None, **update):
                 if not isinstance(value, (set, tuple, list)):
                     value = [value]
                 value = {key: {'$each': value, '$position': position}}
-            elif isinstance(value, list):
-                value = {key: {'$each': value}}
             else:
                 value = {key: value}
         else:

tests/document/instance.py

@@ -3183,6 +3183,17 @@ class InstanceTest(unittest.TestCase):
         blog.reload()
         self.assertEqual(blog.tags, ['mongodb', 'code', 'python'])
 
+    def test_push_nested_list(self):
+        """Ensure that push update works in nested list"""
+        class BlogPost(Document):
+            slug = StringField()
+            tags = ListField()
+
+        blog = BlogPost(slug="test").save()
+        blog.update(push__tags=["value1", 123])
+        blog.reload()
+        self.assertEqual(blog.tags, [["value1", 123]])
+
 
 if __name__ == '__main__':
     unittest.main()

tests/queryset/queryset.py

@@ -1929,6 +1929,21 @@ class QuerySetTest(unittest.TestCase):
         post.reload()
         self.assertEqual(post.tags, ['scala', 'mongodb', 'python', 'java'])
 
+    def test_update_push_list_of_list(self):
+        """Ensure that the 'push' update operation works in the list of list
+        """
+        class BlogPost(Document):
+            slug = StringField()
+            tags = ListField()
+
+        BlogPost.drop_collection()
+
+        post = BlogPost(slug="test").save()
+
+        BlogPost.objects.filter(slug="test").update(push__tags=["value1", 123])
+        post.reload()
+        self.assertEqual(post.tags, [["value1", 123]])
+
     def test_update_push_and_pull_add_to_set(self):
         """Ensure that the 'pull' update operation works correctly.
         """