fix: declaration of required variable in filters v2 (#1136)

* fix: declaration of required variable

* Add unit test

* Fix flaky test

* Formatting

* Fix for python 2.7

Co-authored-by: Thomas Leonard <thomas@loftorbital.com>

graphene_django/converter.py

@@ -69,7 +69,11 @@ def convert_choices_to_named_enum_with_descriptions(name, choices):
         def description(self):
             return named_choices_descriptions[self.name]
 
-    return Enum(name, list(named_choices), type=EnumWithDescriptionsType)
+    if named_choices == []:
+        # Python 2.7 doesn't handle enums with lists with zero entries, but works okay with empty sets
+        named_choices = set()
+
+    return Enum(name, named_choices, type=EnumWithDescriptionsType)
 
 
 def generate_enum_name(django_model_meta, field):

graphene_django/filter/tests/test_enum_filtering.py

@@ -135,10 +135,22 @@ def test_filter_enum_field_schema_type(schema):
         in schema_str
     )
 
-    assert (
-        """type Query {
-  allReporters(offset: Int, before: String, after: String, first: Int, last: Int): ReporterTypeConnection
-  allArticles(offset: Int, before: String, after: String, first: Int, last: Int, lang: ArticleLang, lang_In: [ArticleLang], reporter_AChoice: ReporterAChoice, reporter_AChoice_In: [ReporterAChoice]): ArticleTypeConnection
-}"""
-        in schema_str
+    filters = {
+        "offset": "Int",
+        "before": "String",
+        "after": "String",
+        "first": "Int",
+        "last": "Int",
+        "lang": "ArticleLang",
+        "lang_In": "[ArticleLang]",
+        "reporter_AChoice": "ReporterAChoice",
+        "reporter_AChoice_In": "[ReporterAChoice]",
+    }
+
+    all_articles_filters = (
+        schema_str.split("  allArticles(")[1]
+        .split("): ArticleTypeConnection\n")[0]
+        .split(", ")
     )
+    for filter_field, gql_type in filters.items():
+        assert "{}: {}".format(filter_field, gql_type) in all_articles_filters

graphene_django/filter/tests/test_fields.py

@@ -16,7 +16,7 @@ pytestmark = []
 
 if DJANGO_FILTER_INSTALLED:
     import django_filters
-    from django_filters import FilterSet, NumberFilter
+    from django_filters import FilterSet, NumberFilter, OrderingFilter
 
     from graphene_django.filter import (
         GlobalIDFilter,
@@ -1216,3 +1216,22 @@ def test_filter_string_contains():
     assert result.data == {
         "people": {"edges": [{"node": {"name": "Joe"}}, {"node": {"name": "Bob"}},]}
     }
+
+
+def test_only_custom_filters():
+    class ReporterFilter(FilterSet):
+        class Meta:
+            model = Reporter
+            fields = []
+
+        some_filter = OrderingFilter(fields=("name",))
+
+    class ReporterFilterNode(DjangoObjectType):
+        class Meta:
+            model = Reporter
+            interfaces = (Node,)
+            fields = "__all__"
+            filterset_class = ReporterFilter
+
+    field = DjangoFilterConnectionField(ReporterFilterNode)
+    assert_arguments(field, "some_filter")

graphene_django/filter/utils.py

@@ -39,6 +39,7 @@ def get_filtering_args_from_filterset(filterset_class, type):
     registry = type._meta.registry
     for name, filter_field in six.iteritems(filterset_class.base_filters):
         filter_type = filter_field.lookup_expr
+        required = filter_field.extra.get("required", False)
         field_type = None
         form_field = None
 
@@ -49,8 +50,6 @@ def get_filtering_args_from_filterset(filterset_class, type):
             or isinstance(filter_field, ArrayFilter)
         ):
             # Get the filter field for filters that are no explicitly declared.
-
-            required = filter_field.extra.get("required", False)
             if filter_type == "isnull":
                 field = graphene.Boolean(required=required)
             else: