test_weakset.py 文件源码

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 = [ustr(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))