Issue #5647: MutableSet.__iand__() no longer mutates self during iteration.

This commit is contained in:
Raymond Hettinger 2009-04-01 18:55:57 +00:00
parent 3e7a65f565
commit 38f57a1c75
2 changed files with 28 additions and 4 deletions

View File

@ -286,10 +286,9 @@ class MutableSet(Set):
self.add(value)
return self
def __iand__(self, c):
for value in self:
if value not in c:
self.discard(value)
def __iand__(self, it):
for value in (self - it):
self.discard(value)
return self
def __ixor__(self, it):

View File

@ -311,6 +311,25 @@ class TestOneTrickPonyABCs(ABCTestCase):
B.register(C)
self.failUnless(issubclass(C, B))
class WithSet(MutableSet):
def __init__(self, it=()):
self.data = set(it)
def __len__(self):
return len(self.data)
def __iter__(self):
return iter(self.data)
def __contains__(self, item):
return item in self.data
def add(self, item):
self.data.add(item)
def discard(self, item):
self.data.discard(item)
class TestCollectionABCs(ABCTestCase):
@ -347,6 +366,12 @@ class TestCollectionABCs(ABCTestCase):
self.validate_abstract_methods(MutableSet, '__contains__', '__iter__', '__len__',
'add', 'discard')
def test_issue_5647(self):
# MutableSet.__iand__ mutated the set during iteration
s = WithSet('abcd')
s &= WithSet('cdef') # This used to fail
self.assertEqual(set(s), set('cd'))
def test_issue_4920(self):
# MutableSet.pop() method did not work
class MySet(collections.MutableSet):