def __reduce_ex__(self, *args, **kwargs):
# The `list` reduce function returns an iterator as the fourth element
# that is normally used for repopulating. Since we only inherit from
# `list` for `isinstance` backward compatibility (Refs #17413) we
# nullify this iterator as it would otherwise result in duplicate
# entries. (Refs #23594)
info = super(UserList, self).__reduce_ex__(*args, **kwargs)
return info[:3] + (None, None)
# Utilities for time zone support in DateTimeField et al.
python类UserList()的实例源码
def __init__(self, initlist=[], allowedElems=[]):
collections.UserList.__init__(self, [_f for _f in initlist if _f])
self.allowedElems = sorted(allowedElems)
def __reduce_ex__(self, *args, **kwargs):
# The `list` reduce function returns an iterator as the fourth element
# that is normally used for repopulating. Since we only inherit from
# `list` for `isinstance` backward compatibility (Refs #17413) we
# nullify this iterator as it would otherwise result in duplicate
# entries. (Refs #23594)
info = super(UserList, self).__reduce_ex__(*args, **kwargs)
return info[:3] + (None, None)
# Utilities for time zone support in DateTimeField et al.
def test_writelines_userlist(self):
l = UserList([b'ab', b'cd', b'ef'])
writer = self.MockRawIO()
bufio = self.tp(writer, 8)
bufio.writelines(l)
bufio.flush()
self.assertEqual(b''.join(writer._write_stack), b'abcdef')
def test_writelines_userlist(self):
l = UserList(['ab', 'cd', 'ef'])
buf = self.BytesIO()
txt = self.TextIOWrapper(buf)
txt.writelines(l)
txt.flush()
self.assertEqual(buf.getvalue(), b'abcdef')
def test_join(self):
# join now works with any sequence type
# moved here, because the argument order is
# different in string.join (see the test in
# test.test_string.StringTest.test_join)
self.checkequal('a b c d', ' ', 'join', ['a', 'b', 'c', 'd'])
self.checkequal('abcd', '', 'join', ('a', 'b', 'c', 'd'))
self.checkequal('bd', '', 'join', ('', 'b', '', 'd'))
self.checkequal('ac', '', 'join', ('a', '', 'c', ''))
self.checkequal('w x y z', ' ', 'join', Sequence())
self.checkequal('abc', 'a', 'join', ('abc',))
self.checkequal('z', 'a', 'join', UserList(['z']))
self.checkequal('a.b.c', '.', 'join', ['a', 'b', 'c'])
self.assertRaises(TypeError, '.'.join, ['a', 'b', 3])
for i in [5, 25, 125]:
self.checkequal(((('a' * i) + '-') * i)[:-1], '-', 'join',
['a' * i] * i)
self.checkequal(((('a' * i) + '-') * i)[:-1], '-', 'join',
('a' * i,) * i)
#self.checkequal(str(BadSeq1()), ' ', 'join', BadSeq1())
self.checkequal('a b c', ' ', 'join', BadSeq2())
self.checkraises(TypeError, ' ', 'join')
self.checkraises(TypeError, ' ', 'join', 7)
self.checkraises(TypeError, ' ', 'join', [1, 2, bytes()])
try:
def f():
yield 4 + ""
self.fixtype(' ').join(f())
except TypeError as e:
if '+' not in str(e):
self.fail('join() ate exception message')
else:
self.fail('exception not raised')
def test_basic_proxy(self):
o = C()
self.check_proxy(o, weakref.proxy(o))
L = collections.UserList()
p = weakref.proxy(L)
self.assertFalse(p, "proxy for empty UserList should be false")
p.append(12)
self.assertEqual(len(L), 1)
self.assertTrue(p, "proxy for non-empty UserList should be true")
p[:] = [2, 3]
self.assertEqual(len(L), 2)
self.assertEqual(len(p), 2)
self.assertIn(3, p, "proxy didn't support __contains__() properly")
p[1] = 5
self.assertEqual(L[1], 5)
self.assertEqual(p[1], 5)
L2 = collections.UserList(L)
p2 = weakref.proxy(L2)
self.assertEqual(p, p2)
## self.assertEqual(repr(L2), repr(p2))
L3 = collections.UserList(range(10))
p3 = weakref.proxy(L3)
self.assertEqual(L3[:], p3[:])
self.assertEqual(L3[5:], p3[5:])
self.assertEqual(L3[:5], p3[:5])
self.assertEqual(L3[2:5], p3[2:5])
def test_add_specials(self):
u = UserList("spam")
u2 = u + "eggs"
self.assertEqual(u2, list("spameggs"))
def test_iadd(self):
super().test_iadd()
u = [0, 1]
u += UserList([0, 1])
self.assertEqual(u, [0, 1, 0, 1])
def test_recursion(self):
# Check that comparison for recursive objects fails gracefully
from collections import UserList
a = UserList()
b = UserList()
a.append(b)
b.append(a)
self.assertRaises(RuntimeError, operator.eq, a, b)
self.assertRaises(RuntimeError, operator.ne, a, b)
self.assertRaises(RuntimeError, operator.lt, a, b)
self.assertRaises(RuntimeError, operator.le, a, b)
self.assertRaises(RuntimeError, operator.gt, a, b)
self.assertRaises(RuntimeError, operator.ge, a, b)
b.append(17)
# Even recursive lists of different lengths are different,
# but they cannot be ordered
self.assertTrue(not (a == b))
self.assertTrue(a != b)
self.assertRaises(RuntimeError, operator.lt, a, b)
self.assertRaises(RuntimeError, operator.le, a, b)
self.assertRaises(RuntimeError, operator.gt, a, b)
self.assertRaises(RuntimeError, operator.ge, a, b)
a.append(17)
self.assertRaises(RuntimeError, operator.eq, a, b)
self.assertRaises(RuntimeError, operator.ne, a, b)
a.insert(0, 11)
b.insert(0, 12)
self.assertTrue(not (a == b))
self.assertTrue(a != b)
self.assertTrue(a < b)
def testWritelinesUserList(self):
# verify writelines with instance sequence
l = UserList([b'1', b'2'])
self.f.writelines(l)
self.f.close()
self.f = self.open(TESTFN, 'rb')
buf = self.f.read()
self.assertEqual(buf, b'12')
def testWritelinesIntegersUserList(self):
# verify writelines with integers in UserList
l = UserList([1,2,3])
self.assertRaises(TypeError, self.f.writelines, l)
def test_precomputed(self):
for func, data, elem, expected in self.precomputedCases:
self.assertEqual(func(data, elem), expected)
self.assertEqual(func(UserList(data), elem), expected)
def testWritelinesUserList(self):
l = UserList([b'123', b'456'])
self.f.writelines(l)
self.f.close()
self.f = _FileIO(TESTFN, 'rb')
buf = self.f.read()
self.assertEqual(buf, b'123456')
def test_varargs(self):
f = self.makeCallable('a, b=1, *c')
self.assertEqualCallArgs(f, '2')
self.assertEqualCallArgs(f, '2, 3')
self.assertEqualCallArgs(f, '2, 3, 4')
self.assertEqualCallArgs(f, '*(2,3,4)')
self.assertEqualCallArgs(f, '2, *[3,4]')
self.assertEqualCallArgs(f, '2, 3, *collections.UserList([4])')
def __reduce_ex__(self, *args, **kwargs):
# The `list` reduce function returns an iterator as the fourth element
# that is normally used for repopulating. Since we only inherit from
# `list` for `isinstance` backward compatibility (Refs #17413) we
# nullify this iterator as it would otherwise result in duplicate
# entries. (Refs #23594)
info = super(UserList, self).__reduce_ex__(*args, **kwargs)
return info[:3] + (None, None)
# Utilities for time zone support in DateTimeField et al.
def __reduce_ex__(self, *args, **kwargs):
# The `list` reduce function returns an iterator as the fourth element
# that is normally used for repopulating. Since we only inherit from
# `list` for `isinstance` backward compatibility (Refs #17413) we
# nullify this iterator as it would otherwise result in duplicate
# entries. (Refs #23594)
info = super(UserList, self).__reduce_ex__(*args, **kwargs)
return info[:3] + (None, None)
# Utilities for time zone support in DateTimeField et al.
def __reduce_ex__(self, *args, **kwargs):
# The `list` reduce function returns an iterator as the fourth element
# that is normally used for repopulating. Since we only inherit from
# `list` for `isinstance` backward compatibility (Refs #17413) we
# nullify this iterator as it would otherwise result in duplicate
# entries. (Refs #23594)
info = super(UserList, self).__reduce_ex__(*args, **kwargs)
return info[:3] + (None, None)
# Utilities for time zone support in DateTimeField et al.
def __reduce_ex__(self, *args, **kwargs):
# The `list` reduce function returns an iterator as the fourth element
# that is normally used for repopulating. Since we only inherit from
# `list` for `isinstance` backward compatibility (Refs #17413) we
# nullify this iterator as it would otherwise result in duplicate
# entries. (Refs #23594)
info = super(UserList, self).__reduce_ex__(*args, **kwargs)
return info[:3] + (None, None)
# Utilities for time zone support in DateTimeField et al.
def __init__(self, initlist=[], allowedElems=[]):
collections.UserList.__init__(self, [_f for _f in initlist if _f])
self.allowedElems = sorted(allowedElems)
