Add CurrentUserDefault case

rest_framework/metadata.py

@@ -131,6 +131,9 @@ class SimpleMetadata(BaseMetadata):
         for attr in attrs:
             value = getattr(field, attr, None)
             if value is not None and value != '' and value != empty:
+                if hasattr(value, '__call__'):
+                    value.set_context(field)
+                    value = value()
                 field_info[attr] = force_text(value, strings_only=True)
 
         if getattr(field, 'child', None):

tests/test_metadata.py

@@ -77,6 +77,7 @@ class TestMetadata:
                 )
             )
             nested_field = NestedField()
+            defaultuser_field = serializers.HiddenField(default=serializers.CurrentUserDefault())
 
         class ExampleView(views.APIView):
             """Example view."""
@@ -84,7 +85,10 @@ class TestMetadata:
                 pass
 
             def get_serializer(self):
-                return ExampleSerializer()
+                if self.request:
+                    return ExampleSerializer(context={'request': self.request})
+                else:
+                    return ExampleSerializer()
 
         view = ExampleView.as_view()
         response = view(request=request)
@@ -166,6 +170,13 @@ class TestMetadata:
                                 'label': 'B'
                             }
                         }
+                    },
+                    'defaultuser_field': {
+                        'type': 'field',
+                        'required': False,
+                        'read_only': False,
+                        'label': 'Defaultuser field',
+                        'default': 'AnonymousUser'
                     }
                 }
             }