diff options
Diffstat (limited to 'Lib/weakref.py')
| -rw-r--r-- | Lib/weakref.py | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/Lib/weakref.py b/Lib/weakref.py index 33b8cbc..a4ecadc 100644 --- a/Lib/weakref.py +++ b/Lib/weakref.py @@ -322,6 +322,7 @@ class WeakKeyDictionary(collections.MutableMapping): # A list of dead weakrefs (keys to be removed) self._pending_removals = [] self._iterating = set() + self._dirty_len = False if dict is not None: self.update(dict) @@ -338,13 +339,23 @@ class WeakKeyDictionary(collections.MutableMapping): except KeyError: pass + def _scrub_removals(self): + d = self.data + self._pending_removals = [k for k in self._pending_removals if k in d] + self._dirty_len = False + def __delitem__(self, key): + self._dirty_len = True del self.data[ref(key)] def __getitem__(self, key): return self.data[ref(key)] def __len__(self): + if self._dirty_len and self._pending_removals: + # self._pending_removals may still contain keys which were + # explicitly removed, we have to scrub them (see issue #21173). + self._scrub_removals() return len(self.data) - len(self._pending_removals) def __repr__(self): @@ -417,6 +428,7 @@ class WeakKeyDictionary(collections.MutableMapping): return list(self.data) def popitem(self): + self._dirty_len = True while True: key, value = self.data.popitem() o = key() @@ -424,6 +436,7 @@ class WeakKeyDictionary(collections.MutableMapping): return o, value def pop(self, key, *args): + self._dirty_len = True return self.data.pop(ref(key), *args) def setdefault(self, key, default=None): |