cpython/Lib/test/test_slice.py

147 lines
4.5 KiB
Python

# tests for slice objects; in particular the indices method.
import unittest
import weakref
from cPickle import loads, dumps
from test import test_support
import sys
class SliceTest(unittest.TestCase):
def test_constructor(self):
self.assertRaises(TypeError, slice)
self.assertRaises(TypeError, slice, 1, 2, 3, 4)
def test_repr(self):
self.assertEqual(repr(slice(1, 2, 3)), "slice(1, 2, 3)")
def test_hash(self):
# Verify clearing of SF bug #800796
self.assertRaises(TypeError, hash, slice(5))
with self.assertRaises(TypeError):
slice(5).__hash__()
def test_cmp(self):
s1 = slice(1, 2, 3)
s2 = slice(1, 2, 3)
s3 = slice(1, 2, 4)
self.assertEqual(s1, s2)
self.assertNotEqual(s1, s3)
class Exc(Exception):
pass
class BadCmp(object):
def __eq__(self, other):
raise Exc
__hash__ = None # Silence Py3k warning
s1 = slice(BadCmp())
s2 = slice(BadCmp())
self.assertRaises(Exc, cmp, s1, s2)
self.assertEqual(s1, s1)
s1 = slice(1, BadCmp())
s2 = slice(1, BadCmp())
self.assertEqual(s1, s1)
self.assertRaises(Exc, cmp, s1, s2)
s1 = slice(1, 2, BadCmp())
s2 = slice(1, 2, BadCmp())
self.assertEqual(s1, s1)
self.assertRaises(Exc, cmp, s1, s2)
def test_members(self):
s = slice(1)
self.assertEqual(s.start, None)
self.assertEqual(s.stop, 1)
self.assertEqual(s.step, None)
s = slice(1, 2)
self.assertEqual(s.start, 1)
self.assertEqual(s.stop, 2)
self.assertEqual(s.step, None)
s = slice(1, 2, 3)
self.assertEqual(s.start, 1)
self.assertEqual(s.stop, 2)
self.assertEqual(s.step, 3)
class AnyClass:
pass
obj = AnyClass()
s = slice(obj)
self.assertTrue(s.stop is obj)
def test_indices(self):
self.assertEqual(slice(None ).indices(10), (0, 10, 1))
self.assertEqual(slice(None, None, 2).indices(10), (0, 10, 2))
self.assertEqual(slice(1, None, 2).indices(10), (1, 10, 2))
self.assertEqual(slice(None, None, -1).indices(10), (9, -1, -1))
self.assertEqual(slice(None, None, -2).indices(10), (9, -1, -2))
self.assertEqual(slice(3, None, -2).indices(10), (3, -1, -2))
# issue 3004 tests
self.assertEqual(slice(None, -9).indices(10), (0, 1, 1))
self.assertEqual(slice(None, -10).indices(10), (0, 0, 1))
self.assertEqual(slice(None, -11).indices(10), (0, 0, 1))
self.assertEqual(slice(None, -10, -1).indices(10), (9, 0, -1))
self.assertEqual(slice(None, -11, -1).indices(10), (9, -1, -1))
self.assertEqual(slice(None, -12, -1).indices(10), (9, -1, -1))
self.assertEqual(slice(None, 9).indices(10), (0, 9, 1))
self.assertEqual(slice(None, 10).indices(10), (0, 10, 1))
self.assertEqual(slice(None, 11).indices(10), (0, 10, 1))
self.assertEqual(slice(None, 8, -1).indices(10), (9, 8, -1))
self.assertEqual(slice(None, 9, -1).indices(10), (9, 9, -1))
self.assertEqual(slice(None, 10, -1).indices(10), (9, 9, -1))
self.assertEqual(
slice(-100, 100 ).indices(10),
slice(None).indices(10)
)
self.assertEqual(
slice(100, -100, -1).indices(10),
slice(None, None, -1).indices(10)
)
self.assertEqual(slice(-100L, 100L, 2L).indices(10), (0, 10, 2))
self.assertEqual(range(10)[::sys.maxint - 1], [0])
self.assertRaises(OverflowError, slice(None).indices, 1L<<100)
def test_setslice_without_getslice(self):
tmp = []
class X(object):
def __setslice__(self, i, j, k):
tmp.append((i, j, k))
x = X()
with test_support.check_py3k_warnings():
x[1:2] = 42
self.assertEqual(tmp, [(1, 2, 42)])
def test_pickle(self):
s = slice(10, 20, 3)
for protocol in (0,1,2):
t = loads(dumps(s, protocol))
self.assertEqual(s, t)
self.assertEqual(s.indices(15), t.indices(15))
self.assertNotEqual(id(s), id(t))
def test_cycle(self):
class myobj(): pass
o = myobj()
o.s = slice(o)
w = weakref.ref(o)
o = None
test_support.gc_collect()
self.assertIsNone(w())
def test_main():
test_support.run_unittest(SliceTest)
if __name__ == "__main__":
test_main()