Check exclude fields correctly (#873)

graphene_django/tests/test_types.py

@@ -319,7 +319,7 @@ def test_django_objecttype_fields_exclude_type_checking():
 
 
 @with_local_registry
-def test_django_objecttype_fields_exclude_exist_on_model():
+def test_django_objecttype_fields_exist_on_model():
     with pytest.warns(UserWarning, match=r"Field name .* doesn't exist"):
 
         class Reporter(DjangoObjectType):
@@ -350,6 +350,42 @@ def test_django_objecttype_fields_exclude_exist_on_model():
     assert len(record) == 0
 
 
+@with_local_registry
+def test_django_objecttype_exclude_fields_exist_on_model():
+    with pytest.warns(
+        UserWarning,
+        match=r"Django model .* does not have a field or attribute named .*",
+    ):
+
+        class Reporter(DjangoObjectType):
+            class Meta:
+                model = ReporterModel
+                exclude = ["foo"]
+
+    # Don't warn if selecting a custom field
+    with pytest.warns(
+        UserWarning,
+        match=r"Excluding the custom field .* on DjangoObjectType .* has no effect.",
+    ):
+
+        class Reporter3(DjangoObjectType):
+            custom_field = String()
+
+            class Meta:
+                model = ReporterModel
+                exclude = ["custom_field"]
+
+    # Don't warn on exclude fields
+    with pytest.warns(None) as record:
+
+        class Reporter4(DjangoObjectType):
+            class Meta:
+                model = ReporterModel
+                exclude = ["email", "first_name"]
+
+    assert len(record) == 0
+
+
 class TestDjangoObjectType:
     @pytest.fixture
     def PetModel(self):

graphene_django/types.py

@@ -65,10 +65,7 @@ def construct_fields(
 def validate_fields(type_, model, fields, only_fields, exclude_fields):
     # Validate the given fields against the model's fields and custom fields
     all_field_names = set(fields.keys())
-    for fields_list in (only_fields, exclude_fields):
-        if not fields_list:
-            continue
-        for name in fields_list:
+    for name in only_fields or ():
         if name in all_field_names:
             continue
 
@@ -99,6 +96,35 @@ def validate_fields(type_, model, fields, only_fields, exclude_fields):
                 )
             )
 
+    # Validate exclude fields
+    for name in exclude_fields or ():
+        if name in all_field_names:
+            # Field is a custom field
+            warnings.warn(
+                (
+                    'Excluding the custom field "{field_name} on DjangoObjectType "{type_}" has no effect. '
+                    'Either remove the custom field or remove the field from the "exclude" list.'
+                ).format(
+                    field_name=name,
+                    app_label=model._meta.app_label,
+                    object_name=model._meta.object_name,
+                    type_=type_,
+                )
+            )
+        else:
+            if not hasattr(model, name):
+                warnings.warn(
+                    (
+                        'Django model "{app_label}.{object_name}" does not have a field or attribute named "{field_name}". '
+                        'Consider removing the field from the "exclude" list of DjangoObjectType "{type_}" because it has no effect'
+                    ).format(
+                        field_name=name,
+                        app_label=model._meta.app_label,
+                        object_name=model._meta.object_name,
+                        type_=type_,
+                    )
+                )
+
 
 class DjangoObjectTypeOptions(ObjectTypeOptions):
     model = None  # type: Model