Backport of weakref.WeakSet and tests from Python 3.
diff --git a/Lib/test/test_weakset.py b/Lib/test/test_weakset.py
new file mode 100644
index 0000000..b4774ce
--- /dev/null
+++ b/Lib/test/test_weakset.py
@@ -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)