inheritance bug, fix #49

HISTORY.rst

@@ -10,6 +10,7 @@ v0.3.0 (TBC)
 * ``raise_exception`` removed, Models now always raise exceptions #44
 * instance method validators removed TODO
 * django-restful-framework benchmarks added #47
+* fix inheritance bug #49
 
 v0.2.1 (2017-06-07)
 ...................

pydantic/main.py

@@ -55,7 +55,7 @@ class MetaModel(type):
             fields[var_name] = Field.infer(
                 name=var_name,
                 value=value,
-                annotation=annotations and annotations.pop(var_name, None),
+                annotation=annotations.pop(var_name, None) if annotations else None,
                 class_validators=class_validators,
                 config=config,
             )

pydantic/validators.py

@@ -124,6 +124,9 @@ def find_validators(type_):
     if type_ is Any:
         return []
     for val_type, validators in _VALIDATORS:
-        if issubclass(type_, val_type):
-            return validators
+        try:
+            if issubclass(type_, val_type):
+                return validators
+        except TypeError as e:
+            raise TypeError(f'error checking inheritance of {type_!r} (type: {type(type_)})') from e
     raise ConfigError(f'no validator found for {type_}')

tests/test_complex.py

@@ -426,3 +426,22 @@ def test_values_order():
 
     m = Model(c=30, b=20, a=10)
     assert list(m) == [('a', 10), ('b', 20), ('c', 30)]
+
+
+def test_inheritance():
+    class Foo(BaseModel):
+        a: float = ...
+
+    class Bar(Foo):
+        x: float = 12.3
+        a = 123
+
+    assert Bar().values() == {'x': 12.3, 'a': 123}
+
+
+def test_invalid_type():
+    with pytest.raises(TypeError) as exc_info:
+        class Model(BaseModel):
+            x: 43 = 123
+
+    assert "error checking inheritance of 43 (type: <class 'int'>)" in str(exc_info)