1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
# Python test set -- built-in functions
import test.test_support, unittest
import sys
import pickle
import itertools
import warnings
warnings.filterwarnings("ignore", "integer argument expected",
DeprecationWarning, "unittest")
# pure Python implementations (3 args only), for comparison
def pyrange(start, stop, step):
if (start - stop) // step < 0:
# replace stop with next element in the sequence of integers
# that are congruent to start modulo step.
stop += (start - stop) % step
while start != stop:
yield start
start += step
def pyrange_reversed(start, stop, step):
stop += (start - stop) % step
return pyrange(stop - step, start - step, -step)
class XrangeTest(unittest.TestCase):
def assert_iterators_equal(self, xs, ys, test_id, limit=None):
# check that an iterator xs matches the expected results ys,
# up to a given limit.
if limit is not None:
xs = itertools.islice(xs, limit)
ys = itertools.islice(ys, limit)
sentinel = object()
pairs = itertools.izip_longest(xs, ys, fillvalue=sentinel)
for i, (x, y) in enumerate(pairs):
if x == y:
continue
elif x == sentinel:
self.fail('{}: iterator ended unexpectedly '
'at position {}; expected {}'.format(test_id, i, y))
elif y == sentinel:
self.fail('{}: unexpected excess element {} at '
'position {}'.format(test_id, x, i))
else:
self.fail('{}: wrong element at position {};'
'expected {}, got {}'.format(test_id, i, y, x))
def assert_xranges_equivalent(self, x, y):
# Check that two xrange objects are equivalent, in the sense of the
# associated sequences being the same. We want to use this for large
# xrange objects, so instead of converting to lists and comparing
# directly we do a number of indirect checks.
if len(x) != len(y):
self.fail('{} and {} have different '
'lengths: {} and {} '.format(x, y, len(x), len(y)))
if len(x) >= 1:
if x[0] != y[0]:
self.fail('{} and {} have different initial '
'elements: {} and {} '.format(x, y, x[0], y[0]))
if x[-1] != y[-1]:
self.fail('{} and {} have different final '
'elements: {} and {} '.format(x, y, x[-1], y[-1]))
if len(x) >= 2:
x_step = x[1] - x[0]
y_step = y[1] - y[0]
if x_step != y_step:
self.fail('{} and {} have different step: '
'{} and {} '.format(x, y, x_step, y_step))
def test_xrange(self):
self.assertEqual(list(xrange(3)), [0, 1, 2])
self.assertEqual(list(xrange(1, 5)), [1, 2, 3, 4])
self.assertEqual(list(xrange(0)), [])
self.assertEqual(list(xrange(-3)), [])
self.assertEqual(list(xrange(1, 10, 3)), [1, 4, 7])
self.assertEqual(list(xrange(5, -5, -3)), [5, 2, -1, -4])
a = 10
b = 100
c = 50
self.assertEqual(list(xrange(a, a+2)), [a, a+1])
self.assertEqual(list(xrange(a+2, a, -1L)), [a+2, a+1])
self.assertEqual(list(xrange(a+4, a, -2)), [a+4, a+2])
seq = list(xrange(a, b, c))
self.assertIn(a, seq)
self.assertNotIn(b, seq)
self.assertEqual(len(seq), 2)
seq = list(xrange(b, a, -c))
self.assertIn(b, seq)
self.assertNotIn(a, seq)
self.assertEqual(len(seq), 2)
seq = list(xrange(-a, -b, -c))
self.assertIn(-a, seq)
self.assertNotIn(-b, seq)
self.assertEqual(len(seq), 2)
self.assertRaises(TypeError, xrange)
self.assertRaises(TypeError, xrange, 1, 2, 3, 4)
self.assertRaises(ValueError, xrange, 1, 2, 0)
self.assertRaises(OverflowError, xrange, 10**100, 10**101, 10**101)
self.assertRaises(TypeError, xrange, 0, "spam")
self.assertRaises(TypeError, xrange, 0, 42, "spam")
self.assertEqual(len(xrange(0, sys.maxint, sys.maxint-1)), 2)
self.assertRaises(OverflowError, xrange, -sys.maxint, sys.maxint)
self.assertRaises(OverflowError, xrange, 0, 2*sys.maxint)
r = xrange(-sys.maxint, sys.maxint, 2)
self.assertEqual(len(r), sys.maxint)
self.assertRaises(OverflowError, xrange, -sys.maxint-1, sys.maxint, 2)
def test_pickling(self):
testcases = [(13,), (0, 11), (-22, 10), (20, 3, -1),
(13, 21, 3), (-2, 2, 2)]
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
for t in testcases:
r = xrange(*t)
self.assertEqual(list(pickle.loads(pickle.dumps(r, proto))),
list(r))
M = min(sys.maxint, sys.maxsize)
large_testcases = testcases + [
(0, M, 1),
(M, 0, -1),
(0, M, M - 1),
(M // 2, M, 1),
(0, -M, -1),
(0, -M, 1 - M),
(-M, M, 2),
(-M, M, 1024),
(-M, M, 10585),
(M, -M, -2),
(M, -M, -1024),
(M, -M, -10585),
]
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
for t in large_testcases:
r = xrange(*t)
r_out = pickle.loads(pickle.dumps(r, proto))
self.assert_xranges_equivalent(r_out, r)
def test_repr(self):
# Check that repr of an xrange is a valid representation
# of that xrange.
# Valid xranges have at most min(sys.maxint, sys.maxsize) elements.
M = min(sys.maxint, sys.maxsize)
testcases = [
(13,),
(0, 11),
(-22, 10),
(20, 3, -1),
(13, 21, 3),
(-2, 2, 2),
(0, M, 1),
(M, 0, -1),
(0, M, M - 1),
(M // 2, M, 1),
(0, -M, -1),
(0, -M, 1 - M),
(-M, M, 2),
(-M, M, 1024),
(-M, M, 10585),
(M, -M, -2),
(M, -M, -1024),
(M, -M, -10585),
]
for t in testcases:
r = xrange(*t)
r_out = eval(repr(r))
self.assert_xranges_equivalent(r, r_out)
def test_range_iterators(self):
# see issue 7298
limits = [base + jiggle
for M in (2**32, 2**64)
for base in (-M, -M//2, 0, M//2, M)
for jiggle in (-2, -1, 0, 1, 2)]
test_ranges = [(start, end, step)
for start in limits
for end in limits
for step in (-2**63, -2**31, -2, -1, 1, 2)]
for start, end, step in test_ranges:
try:
iter1 = xrange(start, end, step)
except OverflowError:
pass
else:
iter2 = pyrange(start, end, step)
test_id = "xrange({}, {}, {})".format(start, end, step)
# check first 100 entries
self.assert_iterators_equal(iter1, iter2, test_id, limit=100)
try:
iter1 = reversed(xrange(start, end, step))
except OverflowError:
pass
else:
iter2 = pyrange_reversed(start, end, step)
test_id = "reversed(xrange({}, {}, {}))".format(start, end, step)
self.assert_iterators_equal(iter1, iter2, test_id, limit=100)
def test_main():
test.test_support.run_unittest(XrangeTest)
if __name__ == "__main__":
test_main()
|