Fix distinct bug

graphene_django/fields.py

@@ -67,6 +67,10 @@ def get_manager(self):
 
     @classmethod
     def merge_querysets(cls, default_queryset, queryset):
+        if default_queryset.query.distinct and not queryset.query.distinct:
+            queryset = queryset.distinct()
+        elif queryset.query.distinct and not default_queryset.query.distinct:
+            default_queryset = default_queryset.distinct()
         return queryset & default_queryset
 
     @classmethod

graphene_django/tests/models.py

@@ -19,6 +19,10 @@ class FilmDetails(models.Model):
 
 
 class Film(models.Model):
+    genre = models.CharField(max_length=2, help_text='Genre', choices=[
+        ('do', 'Documentary'),
+        ('ot', 'Other')
+    ], default='ot')
     reporters = models.ManyToManyField('Reporter',
                                        related_name='films')
 

graphene_django/tests/test_query.py

@@ -5,6 +5,8 @@
 from django.utils.functional import SimpleLazyObject
 from py.test import raises
 
+from django.db.models import Q
+
 import graphene
 from graphene.relay import Node
 
@@ -17,6 +19,8 @@
     Article,
     CNNReporter,
     Reporter,
+	Film,
+	FilmDetails,
 )
 
 pytestmark = pytest.mark.django_db
@@ -431,6 +435,60 @@ class Query(graphene.ObjectType):
     assert result.data == expected
 
 
+@pytest.mark.skipif(not DJANGO_FILTER_INSTALLED,
+                    reason="django-filter should be installed")
+def test_should_query_node_filtering_with_distinct_queryset():
+    class FilmType(DjangoObjectType):
+
+        class Meta:
+            model = Film
+            interfaces = (Node, )
+            filter_fields = ('genre',)
+
+    class Query(graphene.ObjectType):
+        films = DjangoConnectionField(FilmType)
+
+        # def resolve_all_reporters_with_berlin_films(self, args, context, info):
+        #    return Reporter.objects.filter(Q(films__film__location__contains="Berlin") | Q(a_choice=1))
+
+        def resolve_films(self, info, **args):
+            return Film.objects.filter(Q(details__location__contains="Berlin") | Q(genre__in=['ot'])).distinct()
+
+    f = Film.objects.create(
+    )
+    fd = FilmDetails.objects.create(
+        location="Berlin",
+        film=f
+    )
+
+    schema = graphene.Schema(query=Query)
+    query = '''
+        query NodeFilteringQuery {
+            films {
+                edges {
+                    node {
+                        genre
+                    }
+                }
+            }
+        }
+    '''
+
+    expected = {
+        'films': {
+            'edges': [{
+                'node': {
+                    'genre': 'OT'
+                }
+            }]
+        }
+    }
+
+    result = schema.execute(query)
+    assert not result.errors
+    assert result.data == expected
+
+
 @pytest.mark.skipif(not DJANGO_FILTER_INSTALLED,
                     reason="django-filter should be installed")
 def test_should_query_node_multiple_filtering():
@@ -676,7 +734,7 @@ class Query(graphene.ObjectType):
 
         def resolve_all_reporters(self, info, **args):
             return Promise.resolve([Reporter(id=1)])
-    
+
     schema = graphene.Schema(query=Query)
     query = '''
         query ReporterPromiseConnectionQuery {
@@ -724,7 +782,7 @@ class Query(graphene.ObjectType):
 
         def resolve_all_reporters(self, info, **args):
             return Reporter.objects.all()
-    
+
     schema = graphene.Schema(query=Query)
     query = '''
         query ReporterLastQuery {
@@ -779,7 +837,7 @@ class Query(graphene.ObjectType):
 
         def resolve_all_reporters(self, info, **args):
             return Reporter.objects.all()
-    
+
     schema = graphene.Schema(query=Query)
     query = '''
         query ReporterLastQuery {
@@ -1012,7 +1070,7 @@ def test_proxy_model_fails():
     """
     This test asserts that if you try to query for a proxy model,
     that query will fail with:
-        GraphQLError('Expected value of type "CNNReporterType" but got: 
+        GraphQLError('Expected value of type "CNNReporterType" but got:
             CNNReporter.',)
 
     This is because a proxy model has the identical model definition