From 327e164869e9fd1bda1a7065863bd1ad13981e32 Mon Sep 17 00:00:00 2001
From: Victor <victor.varvaryuk@mindojo.com>
Date: Thu, 4 Aug 2016 08:31:19 +0300
Subject: [PATCH] Fix for #1176 -- similar to
 https://github.com/MongoEngine/mongoengine/pull/982 but for `update`.

---
 AUTHORS                           | 1 +
 README.rst                        | 2 +-
 docs/changelog.rst                | 1 +
 mongoengine/queryset/transform.py | 6 +++++-
 tests/queryset/transform.py       | 4 ++++
 5 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/AUTHORS b/AUTHORS
index 8a983f86..9ed06c7a 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -239,3 +239,4 @@ that much better:
  * Joshua Nedrud (https://github.com/Neurostack)
  * Shu Shen (https://github.com/shushen)
  * xiaost7 (https://github.com/xiaost7)
+ * Victor Varvaryuk
diff --git a/README.rst b/README.rst
index c94ec45c..547ecbd9 100644
--- a/README.rst
+++ b/README.rst
@@ -99,7 +99,7 @@ Some simple examples of what MongoEngine code looks like:
 Tests
 =====
 To run the test suite, ensure you are running a local instance of MongoDB on
-the standard port, and run: ``python setup.py nosetests``.
+the standard port and have installed ``nose`` and ``rednose``, and run: ``python setup.py nosetests``.
 
 To run the test suite on every supported Python version and every supported PyMongo version,
 you can use ``tox``.
diff --git a/docs/changelog.rst b/docs/changelog.rst
index c52f2776..e71b1ff9 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -16,6 +16,7 @@ Changes in 0.10.7 - DEV
 - Fixed AttributeError when initializing EmbeddedDocument with positional args. #681
 - Fixed no_cursor_timeout error with pymongo 3.0+ #1304
 - Replaced map-reduce based QuerySet.sum/average with aggregation-based implementations #1336
+- Fixed support for `__` to escape field names that match operators names in `update` #1351
 
 Changes in 0.10.6
 =================
diff --git a/mongoengine/queryset/transform.py b/mongoengine/queryset/transform.py
index 13302afa..e5e7f83f 100644
--- a/mongoengine/queryset/transform.py
+++ b/mongoengine/queryset/transform.py
@@ -44,7 +44,7 @@ def query(_doc_cls=None, **kwargs):
         if len(parts) > 1 and parts[-1] in MATCH_OPERATORS:
             op = parts.pop()
 
-        # Allw to escape operator-like field name by __
+        # Allow to escape operator-like field name by __
         if len(parts) > 1 and parts[-1] == "":
             parts.pop()
 
@@ -212,6 +212,10 @@ def update(_doc_cls=None, **update):
         if parts[-1] in COMPARISON_OPERATORS:
             match = parts.pop()
 
+        # Allow to escape operator-like field name by __
+        if len(parts) > 1 and parts[-1] == "":
+            parts.pop()
+
         if _doc_cls:
             # Switch field names to proper names [set in Field(name='foo')]
             try:
diff --git a/tests/queryset/transform.py b/tests/queryset/transform.py
index a543317a..1cb8223d 100644
--- a/tests/queryset/transform.py
+++ b/tests/queryset/transform.py
@@ -224,6 +224,10 @@ class TransformTest(unittest.TestCase):
         self.assertEqual(1, Doc.objects(item__type__="axe").count())
         self.assertEqual(1, Doc.objects(item__name__="Heroic axe").count())
 
+        Doc.objects(id=doc.id).update(set__item__type__='sword')
+        self.assertEqual(1, Doc.objects(item__type__="sword").count())
+        self.assertEqual(0, Doc.objects(item__type__="axe").count())
+
     def test_understandable_error_raised(self):
         class Event(Document):
             title = StringField()