fix test-cov and add extra config check

Author: Ksauder

ninja/orm/metaclass.py

@@ -80,6 +80,13 @@ def __new__(
     ):
         meta_conf = None
 
+        if "Config" in namespace:
+            config_keys = {k for k, _ in getmembers(namespace["Config"])}
+            if any(k in config_keys for k in MetaConf.model_fields.keys()):
+                raise ConfigError(
+                    "class `Config` cannot be used to configure ModelSchema. Use `Meta` instead"
+                )
+
         if "Meta" in namespace:
             conf_class = namespace["Meta"]
             conf_dict = {

tests/test_orm_metaclass.py

@@ -132,10 +132,29 @@ class Meta:
                 fields = "__all__"
 
     class CategorySchema5(ModelSchema):
-        class Config:
+        class Meta:
             model = Category
             fields = "__all__"
 
+    with pytest.raises(
+        ConfigError,
+        match=f"Field title from model {Category} already exists in the Schema",
+    ):
+
+        class CategorySchema6(CategorySchema5):
+            class Meta(CategorySchema5.Meta):
+                fields = ["title"]
+
+    with pytest.raises(
+        ConfigError,
+        match="class `Config` cannot be used to configure ModelSchema. Use `Meta` instead",
+    ):
+
+        class CategorySchema7(ModelSchema):
+            class Config:
+                model = Category
+                fields = "__all__"
+
 
 def test_optional():
     class OptModel(models.Model):