Merge pull request #36 from nyanpasu64/validate-yaml

Validate parameters when loading YAML config

ovgenpy/config.py

@@ -88,20 +88,9 @@ class _ConfigMixin:
 
     # SafeConstructor.construct_yaml_object() uses __setstate__ to load objects.
     def __setstate__(self, state):
-        """ Checks that all fields match their correct types. """
-        self.__dict__.update(state)
-        for field in fields(self):
-            key = field.name
-            value = getattr(self, key)
-            typ = field.type
-
-            # # FIXME crashes on generics, https://github.com/Stewori/pytypes ?
-            # if not isinstance(value, typ):
-            #     name = type(self).__name__
-            #     raise OvgenError(f'{name}.{key} was supplied {repr(value)}, should be of type {typ.__name__}')
-
-        if hasattr(self, '__post_init__'):
-            self.__post_init__()
+        """Call the dataclass constructor, to ensure all parameters are valid."""
+        new = type(self)(**state)
+        self.__dict__ = new.__dict__
 
 
 def register_enum(cls: type):

tests/test_config.py

@@ -71,21 +71,27 @@ b: b
 '''
 
 
-@pytest.mark.xfail(strict=True)
-def test_load_type_checking():
+def test_argument_validation():
+    """ Ensure that loading config via YAML catches missing and invalid parameters. """
     @register_config
-    class Foo:
-        foo: int
-        bar: int
+    class Config:
+        a: int
+
+    yaml.load('''\
+!Config
+  a: 1
+''')
+
+    with pytest.raises(TypeError):
+        yaml.load('!Config {}')
+
+    with pytest.raises(TypeError):
+        yaml.load('''\
+!Config
+  a: 1
+  b: 1
+''')
 
-    s = '''\
-!Foo
-foo: "foo"
-bar: "bar"
-'''
-    with pytest.raises(OvgenError) as e:
-        print(yaml.load(s))
-    print(e)
 
 
 def test_load_post_init():