Field supports cooperative inheritance through **kwargs

README.rst

@@ -1,4 +1,4 @@
-declare 0.9.6
+declare 0.9.7
 ========
 :Build: |build|_ |coverage|_
 :Documentation: http://declare.readthedocs.org/

declare.py

@@ -3,7 +3,7 @@
 import uuid
 __all__ = ["ModelMetaclass", "Field", "TypeDefinition",
            "TypeEngine", "DeclareException"]
-__version__ = "0.9.6"
+__version__ = "0.9.7"
 
 missing = object()
 # These engines can't be cleared
@@ -253,7 +253,7 @@ def __contains__(self, typedef):
 _fixed_engines["global"] = TypeEngine("global")
 
 
-class TypeDefinition(object):
+class TypeDefinition:
     '''
     Translates between python types and backend/storage/transport types
 
@@ -347,8 +347,8 @@ def instanceof(obj, classinfo):
         return False
 
 
-class Field(object):
-    def __init__(self, typedef=None, **kwargs):
+class Field:
+    def __init__(self, *, typedef=None, **kwargs):
         self._model_name = None
         if typedef is None:
             self.typedef = typedef
@@ -361,6 +361,7 @@ def __init__(self, typedef=None, **kwargs):
                 raise TypeError(("Expected {} to be None, instance of "
                                  "TypeDefinition, or subclass of"
                                  "TypeDefinition".format(typedef)))
+        super().__init__(**kwargs)
 
     @property
     def model_name(self):

setup.py

@@ -1,13 +1,9 @@
 """ Setup file """
 import os
-import re
 from setuptools import setup, find_packages
 
 HERE = os.path.abspath(os.path.dirname(__file__))
 README = open(os.path.join(HERE, 'README.rst')).read()
-CHANGES = open(os.path.join(HERE, 'CHANGES.rst')).read()
-# Remove custom RST extensions for pypi
-CHANGES = re.sub(r'\(\s*:(issue|pr|sha):.*?\)', '', CHANGES)
 
 
 def get_version():
@@ -28,7 +24,7 @@ def get_version():
         name='declare',
         version=get_version(),
         description="Declarative scaffolding for frameworks",
-        long_description=README + '\n\n' + CHANGES,
+        long_description=README,
         classifiers=[
             'Development Status :: 4 - Beta',
             'Intended Audience :: Developers',

tests/test_field.py

@@ -105,3 +105,18 @@ def test_wrong_typedef_type():
 
     with pytest.raises(TypeError):
         Field(typedef=int)
+
+
+def test_cooperate_inheritance():
+
+    ''' unused kwargs are delegated to other __init__ methods in the MRO '''
+    class OtherBase:
+        def __init__(self, *, foo, **kwargs):
+            self.foo = foo
+            super().__init__(**kwargs)
+
+    class Class(Field, OtherBase):
+        pass
+
+    obj = Class(typedef=TypeDefinition, foo='bar')
+    assert obj.foo == 'bar'