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
|
# This file is part of Hypothesis, which may be found at
# https://github.com/HypothesisWorks/hypothesis/
#
# Copyright the Hypothesis Authors.
# Individual contributors are listed in AUTHORS.rst and the git log.
#
# This Source Code Form is subject to the terms of the Mozilla Public License,
# v. 2.0. If a copy of the MPL was not distributed with this file, You can
# obtain one at https://mozilla.org/MPL/2.0/.
import pytest
from hypothesis import HealthCheck, Verbosity, assume, example, given, reject, settings
from hypothesis.errors import Flaky, Unsatisfiable, UnsatisfiedAssumption
from hypothesis.internal.conjecture.engine import MIN_TEST_CALLS
from hypothesis.strategies import booleans, composite, integers, lists, random_module
from tests.common.utils import no_shrink
class Nope(Exception):
pass
def test_fails_only_once_is_flaky():
first_call = [True]
@given(integers())
def rude(x):
if first_call[0]:
first_call[0] = False
raise Nope()
with pytest.raises(Flaky):
rude()
def test_gives_flaky_error_if_assumption_is_flaky():
seen = set()
@given(integers())
@settings(verbosity=Verbosity.quiet)
def oops(s):
assume(s not in seen)
seen.add(s)
raise AssertionError
with pytest.raises(Flaky):
oops()
def test_does_not_attempt_to_shrink_flaky_errors():
values = []
@settings(database=None)
@given(integers())
def test(x):
values.append(x)
assert len(values) != 1
with pytest.raises(Flaky):
test()
# We try a total of ten calls in the generation phase, each usually a
# unique value, looking briefly (and unsuccessfully) for another bug.
assert 1 < len(set(values)) <= MIN_TEST_CALLS
# We don't try any new values while shrinking, just execute the test
# twice more (to check for flakiness and to raise the bug to the user).
assert set(values) == set(values[:-2])
class SatisfyMe(Exception):
pass
@composite
def single_bool_lists(draw):
n = draw(integers(0, 20))
result = [False] * (n + 1)
result[n] = True
return result
@example([True, False, False, False], [3], None)
@example([False, True, False, False], [3], None)
@example([False, False, True, False], [3], None)
@example([False, False, False, True], [3], None)
@settings(deadline=None)
@given(lists(booleans()) | single_bool_lists(), lists(integers(1, 3)), random_module())
def test_failure_sequence_inducing(building, testing, rnd):
buildit = iter(building)
testit = iter(testing)
def build(x):
try:
assume(not next(buildit))
except StopIteration:
pass
return x
@given(integers().map(build))
@settings(
verbosity=Verbosity.quiet,
database=None,
suppress_health_check=HealthCheck.all(),
phases=no_shrink,
)
def test(x):
try:
i = next(testit)
except StopIteration:
return
if i == 1:
return
elif i == 2:
reject()
else:
raise Nope()
try:
test()
except (Nope, Unsatisfiable, Flaky):
pass
except UnsatisfiedAssumption:
raise SatisfyMe() from None
|
