Added printing requirements

zope/interface/tests/odd.py

@@ -0,0 +1,129 @@
+##############################################################################
+#
+# Copyright (c) 2003 Zope Foundation and Contributors.
+# All Rights Reserved.
+#
+# This software is subject to the provisions of the Zope Public License,
+# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
+# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
+# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
+# FOR A PARTICULAR PURPOSE.
+#
+##############################################################################
+"""Odd meta class that doesn't subclass type.
+
+This is used for testing support for ExtensionClass in new interfaces.
+
+  >>> class A(object):
+  ...     __metaclass__ = MetaClass
+  ...     a = 1
+  ...
+  >>> A.__name__
+  'A'
+  >>> A.__bases__ == (object,)
+  True
+  >>> class B(object):
+  ...     __metaclass__ = MetaClass
+  ...     b = 1
+  ...
+  >>> class C(A, B): pass
+  ...
+  >>> C.__name__
+  'C'
+  >>> int(C.__bases__ == (A, B))
+  1
+  >>> a = A()
+  >>> aa = A()
+  >>> a.a
+  1
+  >>> aa.a
+  1
+  >>> aa.a = 2
+  >>> a.a
+  1
+  >>> aa.a
+  2
+  >>> c = C()
+  >>> c.a
+  1
+  >>> c.b
+  1
+  >>> c.b = 2
+  >>> c.b
+  2
+  >>> C.c = 1
+  >>> c.c
+  1
+  >>> import sys
+  >>> if sys.version[0] == '2': # This test only makes sense under Python 2.x
+  ...     from types import ClassType
+  ...     assert not isinstance(C, (type, ClassType))
+  
+  >>> int(C.__class__.__class__ is C.__class__)
+  1
+"""
+
+# class OddClass is an odd meta class
+
+class MetaMetaClass(type):
+
+    def __getattribute__(self, name):
+        if name == '__class__':
+            return self
+        return type.__getattribute__(self, name)
+    
+
+class MetaClass(object):
+    """Odd classes
+    """
+    __metaclass__ = MetaMetaClass
+
+    def __init__(self, name, bases, dict):
+        self.__name__ = name
+        self.__bases__ = bases
+        self.__dict__.update(dict)
+
+    def __call__(self):
+        return OddInstance(self)
+
+    def __getattr__(self, name):
+        for b in self.__bases__:
+            v = getattr(b, name, self)
+            if v is not self:
+                return v
+        raise AttributeError(name)
+
+    def __repr__(self):
+        return "<odd class %s at %s>" % (self.__name__, hex(id(self)))
+
+class OddInstance(object):
+
+    def __init__(self, cls):
+        self.__dict__['__class__'] = cls
+
+    def __getattribute__(self, name):
+        dict = object.__getattribute__(self, '__dict__')
+        if name == '__dict__':
+            return dict
+        v = dict.get(name, self)
+        if v is not self:
+            return v
+        return getattr(dict['__class__'], name)
+
+    def __setattr__(self, name, v):
+        self.__dict__[name] = v
+
+    def __delattr__(self, name):
+        del self.__dict__[name]
+
+    def __repr__(self):
+        return "<odd %s instance at %s>" % (
+            self.__class__.__name__, hex(id(self)))
+        
+
+
+# DocTest:
+if __name__ == "__main__":
+    import doctest, __main__
+    doctest.testmod(__main__, isprivate=lambda *a: False)