Make remora_url preserve trailing slashes (bug 565401)

apps/cake/tests.py

@@ -162,3 +162,7 @@ class TestHelpers(TestCase):
         # UTF-8 strings
         url = remora_url(ctx, u'/tags/Hallo und tschüß')
         eq_(url, '/en-US/firefox/tags/Hallo%20und%20tsch%C3%BC%C3%9F')
+
+        # Trailing slashes are kept if present.
+        eq_(remora_url(ctx, '/foo'), '/en-US/firefox/foo')
+        eq_(remora_url(ctx, '/foo/'), '/en-US/firefox/foo/')

apps/cake/urlresolvers.py

@@ -15,6 +15,7 @@ def remora_url(url, lang=None, app=None, prefix=''):
     if app is None:
         app = getattr(prefixer, 'app', settings.DEFAULT_APP)
 
-    url_parts = [p.strip('/') for p in (prefix, lang, app, url) if p]
+    url_parts = [p for p in (
+        prefix.strip('/'), lang, app, url.lstrip('/')) if p]
 
     return url_fix('/'+'/'.join(url_parts))