#
# version: 1 (2004-03-05)
#
class ObjectMerger:
"""
Object 'Merger'.
Returns an instance that takes methods from two given instances/objects.
In order, as if one have the subclass methods of the other.
"""
def __init__(self, super, _self):
self.___super = super
self.___self = _self
def __getattr__ ( self, name ):
if not name.startswith('___'):
super = self.___super
_self = self.___self
if hasattr(_self, name):
return getattr(_self, name)
elif hasattr(super, name):
return getattr(super, name)
return getattr(ObjectMerger, name)
if __name__=='__main__':
import unittest
class test1:
def a(self): pass
def b(self): pass
class test2:
def a(self): pass
def c(self): pass
class testObjectMerger(unittest.TestCase):
def test_merged_instances_method_priority (self):
"""Test priority of methods"""
c1 = test1()
c2 = test2()
m = ObjectMerger(c1, c2)
self.assertEqual(m.a, c2.a)
self.assertEqual(m.b, c1.b)
self.assertEqual(m.c, c2.c)
def test_merged_objects_with_one_noninstance (self):
"""Test mix of instance and object(string)"""
c1 = test1()
c2 = 'hola carlos'
m = ObjectMerger(c1, c2)
self.assertEqual(m.a, c1.a)
#can't compare functions directly because:
# 1. it seems that after first get function is copied..
# or something
# 2. don't know why python fails comparing the function..
self.assertEqual(m.__len__(), c2.__len__())
self.assertEqual(m.b, c1.b)
suite = unittest.TestSuite()
suite.addTest(unittest.makeSuite(testObjectMerger))
unittest.TextTestRunner(verbosity=2).run(suite)
