From 47f8a126ca167cb8fe020e3cc5604b155dfcdebc Mon Sep 17 00:00:00 2001
From: Arto Jantunen <arto@vainu.io>
Date: Tue, 3 Sep 2019 14:36:06 +0300
Subject: [PATCH] Only set no_cursor_timeout when requested

Previously this was always set for all requests. The parameter is only
documented as supported for certain queries, so this was probably wrong.

Mongo version 4.2 fails update queries that have this parameter set making
mongoengine unusable there. Fixes #2148.
---
 mongoengine/queryset/base.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mongoengine/queryset/base.py b/mongoengine/queryset/base.py
index ba3ac95a..ffa099ac 100644
--- a/mongoengine/queryset/base.py
+++ b/mongoengine/queryset/base.py
@@ -1576,7 +1576,9 @@ class BaseQuerySet(object):
         if self._snapshot:
             msg = "The snapshot option is not anymore available with PyMongo 3+"
             warnings.warn(msg, DeprecationWarning)
-        cursor_args = {"no_cursor_timeout": not self._timeout}
+        cursor_args = {}
+        if not self._timeout:
+            cursor_args["no_cursor_timeout"] = True
 
         if self._loaded_fields:
             cursor_args[fields_name] = self._loaded_fields.as_dict()