def test_sequence_not_copied(self):
x, y, z = [1, 2, 3], [4, 5, 6], [7, 8, 9]
seq1 = SequenceZip(x, y, z)
self.assertEqual(seq1[-1], (3, 6, 9))
x[-1], z[-1] = z[-1], x[-1]
self.assertEqual(seq1[-1], (9, 6, 3))
many_large_sequences = [range(1000000) for _ in range(100)]
seq2 = SequenceZip(*many_large_sequences)
self.assertEqual(seq2[-1], (999999, ) * 100)
def test_slicing(self):
seq = SequenceZip(range(5), [1, 2, 3, 4], 'hiya!')
self.assertEqual(list(seq[0:2]), [
(0, 1, 'h'),
(1, 2, 'i'),
])
self.assertEqual(list(seq[1:-1]), [
(1, 2, 'i'),
(2, 3, 'y'),
])
self.assertEqual(list(seq[:-1]), [
(0, 1, 'h'),
(1, 2, 'i'),
(2, 3, 'y'),
])
self.assertEqual(list(seq[-3:]), [
(1, 2, 'i'),
(2, 3, 'y'),
(3, 4, 'a'),
])
self.assertEqual(list(seq[:2]), [
(0, 1, 'h'),
(1, 2, 'i'),
])
self.assertEqual(list(seq[::-1]), [
(3, 4, 'a'),
(2, 3, 'y'),
(1, 2, 'i'),
(0, 1, 'h'),
])
self.assertEqual(list(seq[::-2]), [
(3, 4, 'a'),
(1, 2, 'i'),
])
self.assertEqual(type(seq[-2:]), SequenceZip)
def test_iterable(self):
seq = SequenceZip(range(5), [1, 2, 4], 'hello there')
self.assertEqual(list(seq), [
(0, 1, 'h'),
(1, 2, 'e'),
(2, 4, 'l'),
])
def test_indexing(self):
seq = SequenceZip(range(5), [1, 2, 4], 'hello there')
self.assertEqual(seq[0], (0, 1, 'h'))
self.assertEqual(seq[2], (2, 4, 'l'))
self.assertEqual(seq[-1], seq[2])
with self.assertRaises(IndexError):
seq[3]
def test_equality(self):
seq1 = SequenceZip([1, 2, 3], [4, 5, 6], [7, 8, 9])
seq2 = SequenceZip([1, 2, 3], [4, 5, 6], [7, 8, 9, 0])
seq3 = SequenceZip([1, 2, 3], [4, 5, 4], [7, 8, 9, 0])
self.assertEqual(seq1, seq2)
self.assertNotEqual(seq1, seq3)
self.assertNotEqual(seq1, list(seq2))
from collections import UserList
class SillySequence(UserList):
def __getitem__(self, index):
if not isinstance(index, slice):
raise AssertionError(
"Equality check shouldn't iterate over elements")
return super().__getitem__(index)
def __eq__(self, other):
return self.data == other.data
a = SillySequence([4, 5, 6, 7])
b = SillySequence([4, 5, 6, 7])
c = SillySequence([1, 2, 3, 4])
self.assertEqual(SequenceZip(a, c, b), SequenceZip(b, c, a))
self.assertNotEqual(SequenceZip(c, a, b), SequenceZip(b, c, a))
def test_constructor(self):
SequenceZip([1, 2, 3, 4])
SequenceZip(range(5), [1, 2, 3, 4])
SequenceZip(range(5), [1, 2, 3, 4], 'hello there')
SequenceZip([1], [3], [4, 5], [7], [8, 9])
def test_nice_string_representation(self):
seq = SequenceZip(range(5), [1, 3], 'hiya')
self.assertEqual(
repr(seq),
"SequenceZip(range(0, 5), [1, 3], 'hiya')",
)
def test_length(self):
self.assertEqual(len(SequenceZip([1, 2, 3, 4])), 4)
self.assertEqual(len(SequenceZip(range(5), [1, 2, 3, 4])), 4)
self.assertEqual(len(SequenceZip(range(5), [1, 2, 4], 'hiya')), 3)