if `_app_url` is given it takes precedence

2 files changed, 16 insertions, 7 deletions

diff --git a/pyramid/config/routes.py b/pyramid/config/routes.py
index f4f9ac888..642c72701 100644
--- a/pyramid/config/routes.py
+++ b/pyramid/config/routes.py
@@ -394,13 +394,14 @@ class RoutesConfiguratorMixin(object):
             pattern = parsed.path
 
             def external_url_pregenerator(request, elements, kw):
-              if '_scheme' in kw and parsed.scheme != kw['_scheme']:
-                scheme = kw['_scheme']
-              elif parsed.scheme:
-                scheme = parsed.scheme
-              else:
-                scheme = request.scheme
-              kw['_app_url'] = '{0}://{1}'.format(scheme, parsed.netloc)
+              if not '_app_url' in kw:
+                if '_scheme' in kw and parsed.scheme != kw['_scheme']:
+                  scheme = kw['_scheme']
+                elif parsed.scheme:
+                  scheme = parsed.scheme
+                else:
+                  scheme = request.scheme
+                kw['_app_url'] = '{0}://{1}'.format(scheme, parsed.netloc)
               return elements, kw
 
           pregenerator = external_url_pregenerator
diff --git a/pyramid/tests/test_url.py b/pyramid/tests/test_url.py
index c7b8cfca1..197dfb3eb 100644
--- a/pyramid/tests/test_url.py
+++ b/pyramid/tests/test_url.py
@@ -1062,6 +1062,14 @@ class Test_external_static_url_integration(unittest.TestCase):
             'https://acme.org/path/bar')
 
 
+    def test_generate_external_url_with_explicit_app_url(self):
+        self.config.add_route('acme', 'http://acme.org/path/{foo}')
+        request = self._makeRequest()
+        request.registry = self.config.registry
+        self.assertEqual(request.route_url('acme', foo='bar', _app_url='http://fakeme.com'),
+            'http://fakeme.com/path/bar')
+
+
 class DummyContext(object):
     def __init__(self, next=None):
         self.next = next