Extend and simplify bug fix.

bump version

pure_interface/__init__.py

@@ -7,4 +7,4 @@
 from .adaption import adapts, register_adapter, AdapterTracker, adapt_args
 from .delegation import Delegate
 
-__version__ = '8.0.0'
+__version__ = '8.0.1'

pure_interface/interface.py

@@ -402,20 +402,12 @@ def _ensure_everything_is_abstract(attributes):
     return namespace, functions, interface_method_signatures, interface_attribute_names
 
 
-def _readonly_attribute(name, namespace):
-    # if the attribute is a property with a getter but no setter then it is read-only
-    prop = namespace.get(name)
-    if isinstance(prop, property):
-        if prop.fset is None:
-            return True
-    return False
-
-
 def _ensure_annotations(names, namespace):
     # annotations need to be kept in order, add base-class names first
+    # we only want dataclass annotations for attributes that don't already exist
     annotations = {}
     for name in names:
-        if name not in annotations and not _readonly_attribute(name, namespace):
+        if name not in annotations and name not in namespace:
             annotations[name] = Any
     annotations.update(namespace.get('__annotations__', {}))
     namespace['__annotations__'] = annotations

tests/mypy_source.py

@@ -23,7 +23,7 @@ class MyInterface(BaseInterface, pure_interface.Interface):
 
     @abc.abstractmethod
     def weight(self, arg: int) -> str:
-        pass
+        """weight of the thing."""
 
     @property
     def height(self) -> float:

tests/test_dataclass_support.py

@@ -67,5 +67,19 @@ def foo(self):
                 return 'a={}, b={}, c={}'.format(self.a, self.b, self.c)
 
         f = RoFoo(a=1, c=3)
+        self.assertEqual({'a', 'c'}, set(RoFoo.__annotations__.keys()))
         self.assertEqual(1, f.a)
         self.assertEqual('str', f.b)
+
+    def test_attr_present(self):
+        @dataclass
+        class AFoo(IFoo):
+            a = 10
+
+            def foo(self):
+                return 'a={}, b={}, c={}'.format(self.a, self.b, self.c)
+
+        f = AFoo(b='str')
+        self.assertEqual({'b'}, set(AFoo.__annotations__.keys()))
+        self.assertEqual(10, f.a)
+        self.assertEqual('str', f.b)