Decouple weakref containers from UserDict
and teach them to use ABC instead.
More work left to do later. Still need to
modernize the API of the dictlike objects to
more closely match regulars dicts.
diff --git a/Lib/weakref.py b/Lib/weakref.py
index a9c05d8..b2546f7 100644
--- a/Lib/weakref.py
+++ b/Lib/weakref.py
@@ -9,7 +9,7 @@
# they are called this instead of "ref" to avoid name collisions with
# the module-global ref() function imported from _weakref.
-import UserDict
+import collections
from _weakref import (
getweakrefcount,
@@ -30,7 +30,7 @@
"WeakSet"]
-class WeakValueDictionary(UserDict.UserDict):
+class WeakValueDictionary(collections.MutableMapping):
"""Mapping class that references values weakly.
Entries in the dictionary will be discarded when no strong
@@ -48,7 +48,8 @@
if self is not None:
del self.data[wr.key]
self._remove = remove
- UserDict.UserDict.__init__(self, *args, **kw)
+ self.data = d = {}
+ d.update(*args, **kw)
def __getitem__(self, key):
o = self.data[key]()
@@ -57,6 +58,12 @@
else:
return o
+ def __delitem__(self, key):
+ del self.data[key]
+
+ def __len__(self):
+ return sum(wr() is not None for wr in self.data.values())
+
def __contains__(self, key):
try:
o = self.data[key]()
@@ -187,6 +194,7 @@
L.append(o)
return L
+collections.MutableMapping.register(WeakValueDictionary)
class KeyedRef(ref):
"""Specialized reference that includes a key corresponding to the value.
@@ -209,7 +217,7 @@
super().__init__(ob, callback)
-class WeakKeyDictionary(UserDict.UserDict):
+class WeakKeyDictionary(collections.MutableMapping):
""" Mapping class that references keys weakly.
Entries in the dictionary will be discarded when there is no
@@ -235,6 +243,9 @@
def __getitem__(self, key):
return self.data[ref(key)]
+ def __len__(self):
+ return len(self.data)
+
def __repr__(self):
return "<WeakKeyDictionary at %s>" % id(self)
@@ -339,3 +350,5 @@
d[ref(key, self._remove)] = value
if len(kwargs):
self.update(kwargs)
+
+collections.MutableMapping.register(WeakKeyDictionary)