Fixed how mimeparse receives the list of acceptable formats. Thanks t…

…o bartels & acdha for the report & for looking into possible solutions.

tastypie/utils/mime.py

@@ -25,7 +25,12 @@ def determine_format(request, serializer, default_format='application/json'):
 
     # Try to fallback on the Accepts header.
     if request.META.get('HTTP_ACCEPT', '*/*') != '*/*':
-        best_format = mimeparse.best_match(serializer.supported_formats, request.META['HTTP_ACCEPT'])
+        formats = serializer.supported_formats or []
+        # Reverse the list, because mimeparse is weird like that. See also
+        # https://github.com/toastdriven/django-tastypie/issues#issue/12 for
+        # more information.
+        formats.reverse()
+        best_format = mimeparse.best_match(formats, request.META['HTTP_ACCEPT'])
 
         if best_format:
             return best_format

tests/core/tests/utils.py

@@ -60,3 +60,6 @@ def test_determine_format(self):
 
         request.META = {'HTTP_ACCEPT': 'application/json; charset=UTF-8'}
         self.assertEqual(determine_format(request, serializer), 'application/json')
+
+        request.META = {'HTTP_ACCEPT': 'text/javascript,application/json'}
+        self.assertEqual(determine_format(request, serializer), 'application/json')