Author: michael.foord
Date: Mon Mar 29 22:04:23 2010
New Revision: 79493
Log:
Backport of weakref.WeakSet and tests from Python 3.
Added:
python/trunk/Lib/_weakrefset.py (contents, props changed)
python/trunk/Lib/test/test_weakset.py (contents, props changed)
Modified:
python/trunk/Doc/library/weakref.rst
python/trunk/Lib/unittest/test/test_result.py
python/trunk/Lib/weakref.py
python/trunk/Misc/NEWS
Modified: python/trunk/Doc/library/weakref.rst
==============================================================================
--- python/trunk/Doc/library/weakref.rst (original)
+++ python/trunk/Doc/library/weakref.rst Mon Mar 29 22:04:23 2010
@@ -209,6 +209,14 @@
.. versionadded:: 2.5
+.. class:: WeakSet([elements])
+
+ Set class that keeps weak references to its elements. An element will be
+ discarded when no strong reference to it exists any more.
+
+ .. versionadded:: 2.7
+
+
.. data:: ReferenceType
The type object for weak references objects.
Added: python/trunk/Lib/_weakrefset.py
==============================================================================
--- (empty file)
+++ python/trunk/Lib/_weakrefset.py Mon Mar 29 22:04:23 2010
@@ -0,0 +1,212 @@
+# Access WeakSet through the weakref module.
+# This code is separated-out because it is needed
+# by abc.py to load everything else at startup.
+
+from _weakref import ref
+
+__all__ = ['WeakSet']
+
+
+class _IterationGuard(object):
+ # This context manager registers itself in the current iterators of the
+ # weak container, such as to delay all removals until the context manager
+ # exits.
+ # This technique should be relatively thread-safe (since sets are).
+
+ def __init__(self, weakcontainer):
+ # Don't create cycles
+ self.weakcontainer = ref(weakcontainer)
+
+ def __enter__(self):
+ w = self.weakcontainer()
+ if w is not None:
+ w._iterating.add(self)
+ return self
+
+ def __exit__(self, e, t, b):
+ w = self.weakcontainer()
+ if w is not None:
+ s = w._iterating
+ s.remove(self)
+ if not s:
+ w._commit_removals()
+
+
+class WeakSet(object):
+ def __init__(self, data=None):
+ self.data = set()
+ def _remove(item, selfref=ref(self)):
+ self = selfref()
+ if self is not None:
+ if self._iterating:
+ self._pending_removals.append(item)
+ else:
+ self.data.discard(item)
+ self._remove = _remove
+ # A list of keys to be removed
+ self._pending_removals = []
+ self._iterating = set()
+ if data is not None:
+ self.update(data)
+
+ def _commit_removals(self):
+ l = self._pending_removals
+ discard = self.data.discard
+ while l:
+ discard(l.pop())
+
+ def __iter__(self):
+ with _IterationGuard(self):
+ for itemref in self.data:
+ item = itemref()
+ if item is not None:
+ yield item
+
+ def __len__(self):
+ return sum(x() is not None for x in self.data)
+
+ def __contains__(self, item):
+ return ref(item) in self.data
+
+ def __reduce__(self):
+ return (self.__class__, (list(self),),
+ getattr(self, '__dict__', None))
+
+ __hash__ = None
+
+ def add(self, item):
+ if self._pending_removals:
+ self._commit_removals()
+ self.data.add(ref(item, self._remove))
+
+ def clear(self):
+ if self._pending_removals:
+ self._commit_removals()
+ self.data.clear()
+
+ def copy(self):
+ return self.__class__(self)
+
+ def pop(self):
+ if self._pending_removals:
+ self._commit_removals()
+ while True:
+ try:
+ itemref = self.data.pop()
+ except KeyError:
+ raise KeyError('pop from empty WeakSet')
+ item = itemref()
+ if item is not None:
+ return item
+
+ def remove(self, item):
+ if self._pending_removals:
+ self._commit_removals()
+ self.data.remove(ref(item))
+
+ def discard(self, item):
+ if self._pending_removals:
+ self._commit_removals()
+ self.data.discard(ref(item))
+
+ def update(self, other):
+ if self._pending_removals:
+ self._commit_removals()
+ if isinstance(other, self.__class__):
+ self.data.update(other.data)
+ else:
+ for element in other:
+ self.add(element)
+
+ def __ior__(self, other):
+ self.update(other)
+ return self
+
+ # Helper functions for simple delegating methods.
+ def _apply(self, other, method):
+ if not isinstance(other, self.__class__):
+ other = self.__class__(other)
+ newdata = method(other.data)
+ newset = self.__class__()
+ newset.data = newdata
+ return newset
+
+ def difference(self, other):
+ return self._apply(other, self.data.difference)
+ __sub__ = difference
+
+ def difference_update(self, other):
+ if self._pending_removals:
+ self._commit_removals()
+ if self is other:
+ self.data.clear()
+ else:
+ self.data.difference_update(ref(item) for item in other)
+ def __isub__(self, other):
+ if self._pending_removals:
+ self._commit_removals()
+ if self is other:
+ self.data.clear()
+ else:
+ self.data.difference_update(ref(item) for item in other)
+ return self
+
+ def intersection(self, other):
+ return self._apply(other, self.data.intersection)
+ __and__ = intersection
+
+ def intersection_update(self, other):
+ if self._pending_removals:
+ self._commit_removals()
+ self.data.intersection_update(ref(item) for item in other)
+ def __iand__(self, other):
+ if self._pending_removals:
+ self._commit_removals()
+ self.data.intersection_update(ref(item) for item in other)
+ return self
+
+ def issubset(self, other):
+ return self.data.issubset(ref(item) for item in other)
+ __lt__ = issubset
+
+ def __le__(self, other):
+ return self.data <= set(ref(item) for item in other)
+
+ def issuperset(self, other):
+ return self.data.issuperset(ref(item) for item in other)
+ __gt__ = issuperset
+
+ def __ge__(self, other):
+ return self.data >= set(ref(item) for item in other)
+
+ def __eq__(self, other):
+ if not isinstance(other, self.__class__):
+ return NotImplemented
+ return self.data == set(ref(item) for item in other)
+
+ def symmetric_difference(self, other):
+ return self._apply(other, self.data.symmetric_difference)
+ __xor__ = symmetric_difference
+
+ def symmetric_difference_update(self, other):
+ if self._pending_removals:
+ self._commit_removals()
+ if self is other:
+ self.data.clear()
+ else:
+ self.data.symmetric_difference_update(ref(item) for item in other)
+ def __ixor__(self, other):
+ if self._pending_removals:
+ self._commit_removals()
+ if self is other:
+ self.data.clear()
+ else:
+ self.data.symmetric_difference_update(ref(item) for item in other)
+ return self
+
+ def union(self, other):
+ return self._apply(other, self.data.union)
+ __or__ = union
+
+ def isdisjoint(self, other):
+ return len(self.intersection(other)) == 0
Added: python/trunk/Lib/test/test_weakset.py
==============================================================================
--- (empty file)
+++ python/trunk/Lib/test/test_weakset.py Mon Mar 29 22:04:23 2010
@@ -0,0 +1,376 @@
+import unittest
+from test import test_support
+from weakref import proxy, ref, WeakSet
+import operator
+import copy
+import string
+import os
+from random import randrange, shuffle
+import sys
+import warnings
+import collections
+import gc
+import contextlib
+
+
+class Foo:
+ pass
+
+class SomeClass(object):
+ def __init__(self, value):
+ self.value = value
+ def __eq__(self, other):
+ if type(other) != type(self):
+ return False
+ return other.value == self.value
+
+ def __ne__(self, other):
+ return not self.__eq__(other)
+
+ def __hash__(self):
+ return hash((SomeClass, self.value))
+
+class TestWeakSet(unittest.TestCase):
+
+ def setUp(self):
+ # need to keep references to them
+ self.items = [SomeClass(c) for c in ('a', 'b', 'c')]
+ self.items2 = [SomeClass(c) for c in ('x', 'y', 'z')]
+ self.letters = [SomeClass(c) for c in string.ascii_letters]
+ self.s = WeakSet(self.items)
+ self.d = dict.fromkeys(self.items)
+ self.obj = SomeClass('F')
+ self.fs = WeakSet([self.obj])
+
+ def test_methods(self):
+ weaksetmethods = dir(WeakSet)
+ for method in dir(set):
+ if method == 'test_c_api' or method.startswith('_'):
+ continue
+ self.assertIn(method, weaksetmethods,
+ "WeakSet missing method " + method)
+
+ def test_new_or_init(self):
+ self.assertRaises(TypeError, WeakSet, [], 2)
+
+ def test_len(self):
+ self.assertEqual(len(self.s), len(self.d))
+ self.assertEqual(len(self.fs), 1)
+ del self.obj
+ self.assertEqual(len(self.fs), 0)
+
+ def test_contains(self):
+ for c in self.letters:
+ self.assertEqual(c in self.s, c in self.d)
+ self.assertRaises(TypeError, self.s.__contains__, [[]])
+ self.assertIn(self.obj, self.fs)
+ del self.obj
+ self.assertNotIn(SomeClass('F'), self.fs)
+
+ def test_union(self):
+ u = self.s.union(self.items2)
+ for c in self.letters:
+ self.assertEqual(c in u, c in self.d or c in self.items2)
+ self.assertEqual(self.s, WeakSet(self.items))
+ self.assertEqual(type(u), WeakSet)
+ self.assertRaises(TypeError, self.s.union, [[]])
+ for C in set, frozenset, dict.fromkeys, list, tuple:
+ x = WeakSet(self.items + self.items2)
+ c = C(self.items2)
+ self.assertEqual(self.s.union(c), x)
+
+ def test_or(self):
+ i = self.s.union(self.items2)
+ self.assertEqual(self.s | set(self.items2), i)
+ self.assertEqual(self.s | frozenset(self.items2), i)
+
+ def test_intersection(self):
+ i = self.s.intersection(self.items2)
+ for c in self.letters:
+ self.assertEqual(c in i, c in self.d and c in self.items2)
+ self.assertEqual(self.s, WeakSet(self.items))
+ self.assertEqual(type(i), WeakSet)
+ for C in set, frozenset, dict.fromkeys, list, tuple:
+ x = WeakSet([])
+ self.assertEqual(self.s.intersection(C(self.items2)), x)
+
+ def test_isdisjoint(self):
+ self.assertTrue(self.s.isdisjoint(WeakSet(self.items2)))
+ self.assertTrue(not self.s.isdisjoint(WeakSet(self.letters)))
+
+ def test_and(self):
+ i = self.s.intersection(self.items2)
+ self.assertEqual(self.s & set(self.items2), i)
+ self.assertEqual(self.s & frozenset(self.items2), i)
+
+ def test_difference(self):
+ i = self.s.difference(self.items2)
+ for c in self.letters:
+ self.assertEqual(c in i, c in self.d and c not in self.items2)
+ self.assertEqual(self.s, WeakSet(self.items))
+ self.assertEqual(type(i), WeakSet)
+ self.assertRaises(TypeError, self.s.difference, [[]])
+
+ def test_sub(self):
+ i = self.s.difference(self.items2)
+ self.assertEqual(self.s - set(self.items2), i)
+ self.assertEqual(self.s - frozenset(self.items2), i)
+
+ def test_symmetric_difference(self):
+ i = self.s.symmetric_difference(self.items2)
+ for c in self.letters:
+ self.assertEqual(c in i, (c in self.d) ^ (c in self.items2))
+ self.assertEqual(self.s, WeakSet(self.items))
+ self.assertEqual(type(i), WeakSet)
+ self.assertRaises(TypeError, self.s.symmetric_difference, [[]])
+
+ def test_xor(self):
+ i = self.s.symmetric_difference(self.items2)
+ self.assertEqual(self.s ^ set(self.items2), i)
+ self.assertEqual(self.s ^ frozenset(self.items2), i)
+
+ def test_sub_and_super(self):
+ pl, ql, rl = map(lambda s: [SomeClass(c) for c in s], ['ab', 'abcde', 'def'])
+ p, q, r = map(WeakSet, (pl, ql, rl))
+ self.assertTrue(p < q)
+ self.assertTrue(p <= q)
+ self.assertTrue(q <= q)
+ self.assertTrue(q > p)
+ self.assertTrue(q >= p)
+ self.assertFalse(q < r)
+ self.assertFalse(q <= r)
+ self.assertFalse(q > r)
+ self.assertFalse(q >= r)
+ self.assertTrue(set('a').issubset('abc'))
+ self.assertTrue(set('abc').issuperset('a'))
+ self.assertFalse(set('a').issubset('cbs'))
+ self.assertFalse(set('cbs').issuperset('a'))
+
+ def test_gc(self):
+ # Create a nest of cycles to exercise overall ref count check
+ s = WeakSet(Foo() for i in range(1000))
+ for elem in s:
+ elem.cycle = s
+ elem.sub = elem
+ elem.set = WeakSet([elem])
+
+ def test_subclass_with_custom_hash(self):
+ # Bug #1257731
+ class H(WeakSet):
+ def __hash__(self):
+ return int(id(self) & 0x7fffffff)
+ s=H()
+ f=set()
+ f.add(s)
+ self.assertIn(s, f)
+ f.remove(s)
+ f.add(s)
+ f.discard(s)
+
+ def test_init(self):
+ s = WeakSet()
+ s.__init__(self.items)
+ self.assertEqual(s, self.s)
+ s.__init__(self.items2)
+ self.assertEqual(s, WeakSet(self.items2))
+ self.assertRaises(TypeError, s.__init__, s, 2);
+ self.assertRaises(TypeError, s.__init__, 1);
+
+ def test_constructor_identity(self):
+ s = WeakSet(self.items)
+ t = WeakSet(s)
+ self.assertNotEqual(id(s), id(t))
+
+ def test_hash(self):
+ self.assertRaises(TypeError, hash, self.s)
+
+ def test_clear(self):
+ self.s.clear()
+ self.assertEqual(self.s, WeakSet([]))
+ self.assertEqual(len(self.s), 0)
+
+ def test_copy(self):
+ dup = self.s.copy()
+ self.assertEqual(self.s, dup)
+ self.assertNotEqual(id(self.s), id(dup))
+
+ def test_add(self):
+ x = SomeClass('Q')
+ self.s.add(x)
+ self.assertIn(x, self.s)
+ dup = self.s.copy()
+ self.s.add(x)
+ self.assertEqual(self.s, dup)
+ self.assertRaises(TypeError, self.s.add, [])
+ self.fs.add(Foo())
+ self.assertTrue(len(self.fs) == 1)
+ self.fs.add(self.obj)
+ self.assertTrue(len(self.fs) == 1)
+
+ def test_remove(self):
+ x = SomeClass('a')
+ self.s.remove(x)
+ self.assertNotIn(x, self.s)
+ self.assertRaises(KeyError, self.s.remove, x)
+ self.assertRaises(TypeError, self.s.remove, [])
+
+ def test_discard(self):
+ a, q = SomeClass('a'), SomeClass('Q')
+ self.s.discard(a)
+ self.assertNotIn(a, self.s)
+ self.s.discard(q)
+ self.assertRaises(TypeError, self.s.discard, [])
+
+ def test_pop(self):
+ for i in range(len(self.s)):
+ elem = self.s.pop()
+ self.assertNotIn(elem, self.s)
+ self.assertRaises(KeyError, self.s.pop)
+
+ def test_update(self):
+ retval = self.s.update(self.items2)
+ self.assertEqual(retval, None)
+ for c in (self.items + self.items2):
+ self.assertIn(c, self.s)
+ self.assertRaises(TypeError, self.s.update, [[]])
+
+ def test_update_set(self):
+ self.s.update(set(self.items2))
+ for c in (self.items + self.items2):
+ self.assertIn(c, self.s)
+
+ def test_ior(self):
+ self.s |= set(self.items2)
+ for c in (self.items + self.items2):
+ self.assertIn(c, self.s)
+
+ def test_intersection_update(self):
+ retval = self.s.intersection_update(self.items2)
+ self.assertEqual(retval, None)
+ for c in (self.items + self.items2):
+ if c in self.items2 and c in self.items:
+ self.assertIn(c, self.s)
+ else:
+ self.assertNotIn(c, self.s)
+ self.assertRaises(TypeError, self.s.intersection_update, [[]])
+
+ def test_iand(self):
+ self.s &= set(self.items2)
+ for c in (self.items + self.items2):
+ if c in self.items2 and c in self.items:
+ self.assertIn(c, self.s)
+ else:
+ self.assertNotIn(c, self.s)
+
+ def test_difference_update(self):
+ retval = self.s.difference_update(self.items2)
+ self.assertEqual(retval, None)
+ for c in (self.items + self.items2):
+ if c in self.items and c not in self.items2:
+ self.assertIn(c, self.s)
+ else:
+ self.assertNotIn(c, self.s)
+ self.assertRaises(TypeError, self.s.difference_update, [[]])
+ self.assertRaises(TypeError, self.s.symmetric_difference_update, [[]])
+
+ def test_isub(self):
+ self.s -= set(self.items2)
+ for c in (self.items + self.items2):
+ if c in self.items and c not in self.items2:
+ self.assertIn(c, self.s)
+ else:
+ self.assertNotIn(c, self.s)
+
+ def test_symmetric_difference_update(self):
+ retval = self.s.symmetric_difference_update(self.items2)
+ self.assertEqual(retval, None)
+ for c in (self.items + self.items2):
+ if (c in self.items) ^ (c in self.items2):
+ self.assertIn(c, self.s)
+ else:
+ self.assertNotIn(c, self.s)
+ self.assertRaises(TypeError, self.s.symmetric_difference_update, [[]])
+
+ def test_ixor(self):
+ self.s ^= set(self.items2)
+ for c in (self.items + self.items2):
+ if (c in self.items) ^ (c in self.items2):
+ self.assertIn(c, self.s)
+ else:
+ self.assertNotIn(c, self.s)
+
+ def test_inplace_on_self(self):
+ t = self.s.copy()
+ t |= t
+ self.assertEqual(t, self.s)
+ t &= t
+ self.assertEqual(t, self.s)
+ t -= t
+ self.assertEqual(t, WeakSet())
+ t = self.s.copy()
+ t ^= t
+ self.assertEqual(t, WeakSet())
+
+ def test_eq(self):
+ # issue 5964
+ self.assertTrue(self.s == self.s)
+ self.assertTrue(self.s == WeakSet(self.items))
+ self.assertFalse(self.s == set(self.items))
+ self.assertFalse(self.s == list(self.items))
+ self.assertFalse(self.s == tuple(self.items))
+ self.assertFalse(self.s == 1)
+
+ def test_weak_destroy_while_iterating(self):
+ # Issue #7105: iterators shouldn't crash when a key is implicitly removed
+ # Create new items to be sure no-one else holds a reference
+ items = [SomeClass(c) for c in ('a', 'b', 'c')]
+ s = WeakSet(items)
+ it = iter(s)
+ next(it) # Trigger internal iteration
+ # Destroy an item
+ del items[-1]
+ gc.collect() # just in case
+ # We have removed either the first consumed items, or another one
+ self.assertIn(len(list(it)), [len(items), len(items) - 1])
+ del it
+ # The removal has been committed
+ self.assertEqual(len(s), len(items))
+
+ def test_weak_destroy_and_mutate_while_iterating(self):
+ # Issue #7105: iterators shouldn't crash when a key is implicitly removed
+ items = [SomeClass(c) for c in string.ascii_letters]
+ s = WeakSet(items)
+ @contextlib.contextmanager
+ def testcontext():
+ try:
+ it = iter(s)
+ next(it)
+ # Schedule an item for removal and recreate it
+ u = SomeClass(str(items.pop()))
+ gc.collect() # just in case
+ yield u
+ finally:
+ it = None # should commit all removals
+
+ with testcontext() as u:
+ self.assertNotIn(u, s)
+ with testcontext() as u:
+ self.assertRaises(KeyError, s.remove, u)
+ self.assertNotIn(u, s)
+ with testcontext() as u:
+ s.add(u)
+ self.assertIn(u, s)
+ t = s.copy()
+ with testcontext() as u:
+ s.update(t)
+ self.assertEqual(len(s), len(t))
+ with testcontext() as u:
+ s.clear()
+ self.assertEqual(len(s), 0)
+
+
+def test_main(verbose=None):
+ test_support.run_unittest(TestWeakSet)
+
+if __name__ == "__main__":
+ test_main(verbose=True)
Modified: python/trunk/Lib/unittest/test/test_result.py
==============================================================================
--- python/trunk/Lib/unittest/test/test_result.py (original)
+++ python/trunk/Lib/unittest/test/test_result.py Mon Mar 29 22:04:23 2010
@@ -24,6 +24,7 @@
self.assertEqual(result.testsRun, 0)
self.assertEqual(result.shouldStop, False)
+
# "This method can be called to signal that the set of tests being
# run should be aborted by setting the TestResult's shouldStop
# attribute to True."
Modified: python/trunk/Lib/weakref.py
==============================================================================
--- python/trunk/Lib/weakref.py (original)
+++ python/trunk/Lib/weakref.py Mon Mar 29 22:04:23 2010
@@ -20,6 +20,8 @@
ProxyType,
ReferenceType)
+from _weakrefset import WeakSet
+
from exceptions import ReferenceError
@@ -27,7 +29,7 @@
__all__ = ["ref", "proxy", "getweakrefcount", "getweakrefs",
"WeakKeyDictionary", "ReferenceError", "ReferenceType", "ProxyType",
- "CallableProxyType", "ProxyTypes", "WeakValueDictionary"]
+ "CallableProxyType", "ProxyTypes", "WeakValueDictionary", 'WeakSet']
class WeakValueDictionary(UserDict.UserDict):
Modified: python/trunk/Misc/NEWS
==============================================================================
--- python/trunk/Misc/NEWS (original)
+++ python/trunk/Misc/NEWS Mon Mar 29 22:04:23 2010
@@ -37,6 +37,8 @@
True/False. This makes Fraction <=> complex comparisons consistent with
int <=> complex, float <=> complex, and complex <=> complex comparisons.
+- Addition of ``WeakSet`` to the ``weakref`` module.
+
- logging: Added LOG_FTP to SysLogHandler and updated documentation.
- Issue #8205: Remove the "Modules" directory from sys.path when Python is
