From 6663bf1f7d5a43633e6434a5dd8ea8f8eccdd616 Mon Sep 17 00:00:00 2001
From: ThiefMaster <adrian@planetcoding.net>
Date: Fri, 27 Apr 2018 13:38:35 +0200
Subject: [PATCH] Fix registering partials as view functions

---
 CHANGES.rst              | 1 +
 flask/blueprints.py      | 2 +-
 tests/test_blueprints.py | 3 +++
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/CHANGES.rst b/CHANGES.rst
index c6415447b7..9ad5bb36a5 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -9,6 +9,7 @@ Version 1.0.1
 
 unreleased
 
+-   Fix registering partials (with no ``__name__``) as view functions
 
 Version 1.0
 -----------
diff --git a/flask/blueprints.py b/flask/blueprints.py
index d633685fbd..0a6ccfb76e 100644
--- a/flask/blueprints.py
+++ b/flask/blueprints.py
@@ -201,7 +201,7 @@ def add_url_rule(self, rule, endpoint=None, view_func=None, **options):
         """
         if endpoint:
             assert '.' not in endpoint, "Blueprint endpoints should not contain dots"
-        if view_func:
+        if view_func and hasattr(view_func, '__name__'):
             assert '.' not in view_func.__name__, "Blueprint view function name should not contain dots"
         self.record(lambda s:
             s.add_url_rule(rule, endpoint, view_func, **options))
diff --git a/tests/test_blueprints.py b/tests/test_blueprints.py
index 7984a815e6..a26312416e 100644
--- a/tests/test_blueprints.py
+++ b/tests/test_blueprints.py
@@ -9,6 +9,7 @@
     :license: BSD, see LICENSE for more details.
 """
 
+import functools
 import pytest
 
 import flask
@@ -382,6 +383,8 @@ def foo_foo_foo():
         )
     )
 
+    bp.add_url_rule('/bar/456', endpoint='foofoofoo', view_func=functools.partial(foo_foo_foo))
+
     app.register_blueprint(bp, url_prefix='/py')
 
     assert client.get('/py/foo').data == b'bp.foo'