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# coding=utf-8
#
# This file is part of Hypothesis, which may be found at
# https://github.com/HypothesisWorks/hypothesis-python
#
# Most of this work is copyright (C) 2013-2015 David R. MacIver
# (david@drmaciver.com), but it contains contributions by others. See
# CONTRIBUTING.rst for a full list of people who may hold copyright, and
# consult the git log if you need to determine who owns an individual
# contribution.
#
# 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 http://mozilla.org/MPL/2.0/.
#
# END HEADER
from __future__ import division, print_function, absolute_import
import pytest
from hypothesis import given, assume, reject, example, settings, Verbosity
from hypothesis.errors import Flaky, Unsatisfiable, UnsatisfiedAssumption
from hypothesis.strategies import lists, booleans, integers, composite, \
random_module
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)
assert False
with pytest.raises(Flaky):
oops()
def test_does_not_attempt_to_shrink_flaky_errors():
values = []
@given(integers())
def test(x):
values.append(x)
assert len(values) != 1
with pytest.raises(Flaky):
test()
assert len(set(values)) == 1
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(max_examples=0)
@given(
lists(booleans(), average_size=20) | single_bool_lists(),
lists(integers(1, 3), average_size=20), 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,
perform_health_check=False, max_shrinks=0
)
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()
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