Fix registering partials as view functions

CHANGES.rst

@@ -9,6 +9,7 @@ Version 1.0.1
 
 unreleased
 
+-   Fix registering partials (with no ``__name__``) as view functions
 
 Version 1.0
 -----------

flask/blueprints.py

@@ -201,7 +201,7 @@ class Blueprint(_PackageBoundObject):
         """
         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))

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 test_route_decorator_custom_endpoint_with_dots(app, client):
         )
     )
 
+    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'