Merge pull request #3045 from paxnovem/issue_3042

Fixed many=False issue on related fields

rest_framework/relations.py

@@ -42,6 +42,7 @@ class RelatedField(Field):
             'Relational fields should not provide a `queryset` argument, '
             'when setting read_only=`True`.'
         )
+        kwargs.pop('many', None)
         super(RelatedField, self).__init__(**kwargs)
 
     def __new__(cls, *args, **kwargs):

tests/test_relations.py

@@ -48,6 +48,11 @@ class TestPrimaryKeyRelatedField(APISimpleTestCase):
         representation = self.field.to_representation(self.instance)
         assert representation == self.instance.pk
 
+    def test_explicit_many_false(self):
+        field = serializers.PrimaryKeyRelatedField(queryset=self.queryset, many=False)
+        instance = field.to_internal_value(self.instance.pk)
+        assert instance is self.instance
+
 
 class TestProxiedPrimaryKeyRelatedField(APISimpleTestCase):
     def setUp(self):