raise error when given extra fields for dataclasses

src/glorpen/config/config.py

@@ -116,14 +116,18 @@ def _get_default_factory(cls, field: dataclasses.Field):
     def _from_dataclass(self, data: typing.Dict, cls):
         kwargs = {}
         errors = {}
-        # TODO: error on when more fields are provided
+        known_fields = set()
         for field in dataclasses.fields(cls):
+            known_fields.add(field.name)
             try:
                 kwargs[field.name] = self._as_model(data.get(field.name), field.type, metadata=field.metadata,
                     default_factory=self._get_default_factory(field))
             except ValueError as e:
                 errors[field.name] = e
 
+        for extra_field in set(data.keys()).difference(known_fields):
+            errors[extra_field] = ValueError("Extra field")
+
         if errors:
             raise CollectionValueError(errors)
 

tests/test_config.py

@@ -39,6 +39,17 @@ class Data:
         assert m.value_field == "default-value"
         assert m.optional_field is None
 
+    def test_too_many_properties(self):
+        c = create_config()
+        c.register_type(SimpleTypes)
+
+        @dataclasses.dataclass
+        class Data:
+            a_prop: str
+
+        with pytest.raises(ValueError, match="Extra field"):
+            c.to_model({"a_prop": "asd", "test": "test"}, Data)
+
     def test_validation_with_asserts(self):
         c = create_config()
         c.register_type(SimpleTypes)