# Test case for property
# more tests are in test_descr
import sys
import unittest
from test.test_support import run_unittest
class PropertyBase(Exception):
pass
class PropertyGet(PropertyBase):
pass
class PropertySet(PropertyBase):
pass
class PropertyDel(PropertyBase):
pass
class BaseClass(object):
def __init__(self):
self._spam = 5
@property
def spam(self):
"""BaseClass.getter"""
return self._spam
@spam.setter
def spam(self, value):
self._spam = value
@spam.deleter
def spam(self):
del self._spam
class SubClass(BaseClass):
@BaseClass.spam.getter
def spam(self):
"""SubClass.getter"""
raise PropertyGet(self._spam)
@spam.setter
def spam(self, value):
raise PropertySet(self._spam)
@spam.deleter
def spam(self):
raise PropertyDel(self._spam)
class PropertyDocBase(object):
_spam = 1
def _get_spam(self):
return self._spam
spam = property(_get_spam, doc="spam spam spam")
class PropertyDocSub(PropertyDocBase):
@PropertyDocBase.spam.getter
def spam(self):
"""The decorator does not use this doc string"""
return self._spam
class PropertySubNewGetter(BaseClass):
@BaseClass.spam.getter
def spam(self):
"""new docstring"""
return 5
class PropertyNewGetter(object):
@property
def spam(self):
"""original docstring"""
return 1
@spam.getter
def spam(self):
"""new docstring"""
return 8
class PropertyTests(unittest.TestCase):
def test_property_decorator_baseclass(self):
# see #1620
base = BaseClass()
self.assertEqual(base.spam, 5)
self.assertEqual(base._spam, 5)
base.spam = 10
self.assertEqual(base.spam, 10)
self.assertEqual(base._spam, 10)
delattr(base, "spam")
self.assertTrue(not hasattr(base, "spam"))
self.assertTrue(not hasattr(base, "_spam"))
base.spam = 20
self.assertEqual(base.spam, 20)
self.assertEqual(base._spam, 20)
def test_property_decorator_subclass(self):
# see #1620
sub = SubClass()
self.assertRaises(PropertyGet, getattr, sub, "spam")
self.assertRaises(PropertySet, setattr, sub, "spam", None)
self.assertRaises(PropertyDel, delattr, sub, "spam")
@unittest.skipIf(sys.flags.optimize >= 2,
"Docstrings are omitted with -O2 and above")
def test_property_decorator_subclass_doc(self):
sub = SubClass()
self.assertEqual(sub.__class__.spam.__doc__, "SubClass.getter")
@unittest.skipIf(sys.flags.optimize >= 2,
"Docstrings are omitted with -O2 and above")
def test_property_decorator_baseclass_doc(self):
base = BaseClass()
self.assertEqual(base.__class__.spam.__doc__, "BaseClass.getter")
def test_property_decorator_doc(self):
base = PropertyDocBase()
sub = PropertyDocSub()
self.assertEqual(base.__class__.spam.__doc__, "spam spam spam")
self.assertEqual(sub.__class__.spam.__doc__, "spam spam spam")
@unittest.skipIf(sys.flags.optimize >= 2,
"Docstrings are omitted with -O2 and above")
def test_property_getter_doc_override(self):
newgettersub = PropertySubNewGetter()
self.assertEqual(newgettersub.spam, 5)
self.assertEqual(newgettersub.__class__.spam.__doc__, "new docstring")
newgetter = PropertyNewGetter()
self.assertEqual(newgetter.spam, 8)
self.assertEqual(newgetter.__class__.spam.__doc__, "new docstring")
# Issue 5890: subclasses of property do not preserve method __doc__ strings
class PropertySub(property):
"""This is a subclass of property"""
class PropertySubSlots(property):
"""This is a subclass of property that defines __slots__"""
__slots__ = ()
class PropertySubclassTests(unittest.TestCase):
def test_slots_docstring_copy_exception(self):
try:
class Foo(object):
@PropertySubSlots
def spam(self):
"""Trying to copy this docstring will raise an exception"""
return 1
except AttributeError:
pass
else:
raise Exception("AttributeError not raised")
@unittest.skipIf(sys.flags.optimize >= 2,
"Docstrings are omitted with -O2 and above")
def test_docstring_copy(self):
class Foo(object):
@PropertySub
def spam(self):
"""spam wrapped in property subclass"""
return 1
self.assertEqual(
Foo.spam.__doc__,
"spam wrapped in property subclass")
@unittest.skipIf(sys.flags.optimize >= 2,
"Docstrings are omitted with -O2 and above")
def test_property_setter_copies_getter_docstring(self):
class Foo(object):
def __init__(self): self._spam = 1
@PropertySub
def spam(self):
"""spam wrapped in property subclass"""
return self._spam
@spam.setter
def spam(self, value):
"""this docstring is ignored"""
self._spam = value
foo = Foo()
self.assertEqual(foo.spam, 1)
foo.spam = 2
self.assertEqual(foo.spam, 2)
self.assertEqual(
Foo.spam.__doc__,
"spam wrapped in property subclass")
class FooSub(Foo):
@Foo.spam.setter
def spam(self, value):
"""another ignored docstring"""
self._spam = 'eggs'
foosub = FooSub()
self.assertEqual(foosub.spam, 1)
foosub.spam = 7
self.assertEqual(foosub.spam, 'eggs')
self.assertEqual(
FooSub.spam.__doc__,
"spam wrapped in property subclass")
@unittest.skipIf(sys.flags.optimize >= 2,
"Docstrings are omitted with -O2 and above")
def test_property_new_getter_new_docstring(self):
class Foo(object):
@PropertySub
def spam(self):
"""a docstring"""
return 1
@spam.getter
def spam(self):
"""a new docstring"""
return 2
self.assertEqual(Foo.spam.__doc__, "a new docstring")
class FooBase(object):
@PropertySub
def spam(self):
"""a docstring"""
return 1
class Foo2(FooBase):
@FooBase.spam.getter
def spam(self):
"""a new docstring"""
return 2
self.assertEqual(Foo.spam.__doc__, "a new docstring")
def test_main():
run_unittest(PropertyTests, PropertySubclassTests)
if __name__ == '__main__':
test_main()