Issue #9214: Fix set operations on KeysView and ItemsView.
diff --git a/Lib/_abcoll.py b/Lib/_abcoll.py
index 7890e97..d3e23c1 100644
--- a/Lib/_abcoll.py
+++ b/Lib/_abcoll.py
@@ -393,6 +393,10 @@
class KeysView(MappingView, Set):
+ @classmethod
+ def _from_iterable(self, it):
+ return set(it)
+
def __contains__(self, key):
return key in self._mapping
@@ -405,6 +409,10 @@
class ItemsView(MappingView, Set):
+ @classmethod
+ def _from_iterable(self, it):
+ return set(it)
+
def __contains__(self, item):
key, value = item
try:
diff --git a/Lib/test/test_collections.py b/Lib/test/test_collections.py
index 85bf248..be41fcd 100644
--- a/Lib/test/test_collections.py
+++ b/Lib/test/test_collections.py
@@ -13,7 +13,7 @@
from collections import Hashable, Iterable, Iterator
from collections import Sized, Container, Callable
from collections import Set, MutableSet
-from collections import Mapping, MutableMapping
+from collections import Mapping, MutableMapping, KeysView, ItemsView, UserDict
from collections import Sequence, MutableSequence
from collections import ByteString
@@ -516,6 +516,31 @@
self.validate_abstract_methods(MutableMapping, '__contains__', '__iter__', '__len__',
'__getitem__', '__setitem__', '__delitem__')
+ def test_MutableMapping_subclass(self):
+ # Test issue 9214
+ mymap = UserDict()
+ mymap['red'] = 5
+ self.assert_(isinstance(mymap.keys(), Set))
+ self.assert_(isinstance(mymap.keys(), KeysView))
+ self.assert_(isinstance(mymap.items(), Set))
+ self.assert_(isinstance(mymap.items(), ItemsView))
+
+ mymap = UserDict()
+ mymap['red'] = 5
+ z = mymap.keys() | {'orange'}
+ self.assertEqual(type(z), set)
+ list(z)
+ mymap['blue'] = 7 # Shouldn't affect 'z'
+ self.assertEqual(sorted(z), ['orange', 'red'])
+
+ mymap = UserDict()
+ mymap['red'] = 5
+ z = mymap.items() | {('orange', 3)}
+ self.assertEqual(type(z), set)
+ list(z)
+ mymap['blue'] = 7 # Shouldn't affect 'z'
+ self.assertEqual(sorted(z), [('orange', 3), ('red', 5)])
+
def test_Sequence(self):
for sample in [tuple, list, bytes, str]:
self.assertTrue(isinstance(sample(), Sequence))
diff --git a/Misc/NEWS b/Misc/NEWS
index 9a48c5e..d88a483 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -95,6 +95,9 @@
Library
-------
+- Issue #9214: Set operations on KeysView or ItemsView in the collections
+ module now correctly return a set. (Patch by Eli Bendersky.)
+
- Issue #9617: Signals received during a low-level write operation aren't
ignored by the buffered IO layer anymore.