def test_does_not_falsify_if_all_args_given():
verifier = Verifier()
verifier.falsify = None
@given(int, int, verifier=verifier)
def foo(x, y):
pass
foo(1, 2)
def test_a_verifier_retrieves_previous_failing_examples_from_the_database():
database = ExampleDatabase()
verifier = Verifier(settings=hs.Settings(database=database))
verifier.falsify(lambda x: x < 11, int)
called = []
def save_calls(t):
called.append(t)
return False
verifier2 = Verifier(settings=hs.Settings(database=database))
verifier2.falsify(save_calls, int)
assert called[0] == 11
assert all(0 <= x <= 11 for x in called)
from hypothesis.internal.verifier import Verifier
hs.Settings.default.max_examples = 1000
TestStandardDescriptorFeatures1 = strategy_test_suite(datetime)
TestStandardDescriptorFeatures2 = strategy_test_suite(
timezone_aware_datetime)
TestStandardDescriptorFeatures3 = strategy_test_suite(naive_datetime)
TestStandardDescriptorFeatures4 = strategy_test_suite(one_of((
naive_datetime,
timezone_aware_datetime,
)))
falsify = Verifier().falsify
def test_can_find_after_the_year_2000():
falsify(lambda x: x.year > 2000, datetime)
def test_can_find_before_the_year_2000():
falsify(lambda x: x.year < 2000, datetime)
def test_can_find_each_month():
for i in hrange(1, 12):
falsify(lambda x: x.month != i, datetime)
def test_french_names_may_have_an_accent():
Verifier().falsify(lambda x: 'é' not in x,
FakeFactory('name', locale='fr_FR'))
def test_can_falsify_in_derandomize_mode():
settings = Settings(derandomize=True)
v = Verifier(settings=settings)
v.falsify(lambda x: x > 0, int)
def test_verifier_explodes_when_you_mix_random_and_derandom():
settings = Settings(derandomize=True)
with pytest.raises(ValueError):
Verifier(settings=settings, random=Random())
# coding=utf-8 # Copyright (C) 2013-2015 David R. MacIver ([email protected]) # This file is part of Hypothesis (https://github.com/DRMacIver/hypothesis) # 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 hypothesis.internal.verifier import Verifier import hypothesis.settings as hs settings = hs.Settings(max_examples=100, timeout=4) small_verifier = Verifier(settings=settings, )
def given(*generator_arguments, **generator_kwargs):
"""A decorator for turning a test function that accepts arguments into a
randomized test.
This is the main entry point to Hypothesis. See the full tutorial
for details of its behaviour.
"""
if 'verifier' in generator_kwargs:
verifier = generator_kwargs.pop('verifier')
verifier.start_time = time.time()
else:
verifier = Verifier(
settings=generator_kwargs.pop('settings', None),
random=generator_kwargs.pop('random', None),
)
if not (generator_arguments or generator_kwargs):
raise InvalidArgument(
'given must be called with at least one argument')
def run_test_with_generator(test):
original_argspec = inspect.getargspec(test)
if original_argspec.varargs:
raise InvalidArgument('varargs are not supported with @given')
extra_kwargs = [
k for k in generator_kwargs if k not in original_argspec.args
]
if extra_kwargs and not original_argspec.keywords:
raise InvalidArgument(
'%s() got an unexpected keyword argument %r' %
(test.__name__, extra_kwargs[0]))
if (len(generator_arguments) > len(original_argspec.args)):
raise InvalidArgument(
('Too many positional arguments for %s() (got %d but'
' expected at most %d') %
(test.__name__, len(generator_arguments),
len(original_argspec.args)))
arguments = original_argspec.args + sorted(extra_kwargs)
specifiers = list(generator_arguments)
for a in arguments:
if a in generator_kwargs:
specifiers.append(generator_kwargs[a])
argspec = inspect.ArgSpec(args=arguments,
keywords=original_argspec.keywords,
varargs=original_argspec.varargs,
defaults=tuple(
map(HypothesisProvided, specifiers)))
@copy_argspec(test.__name__, argspec)
def wrapped_test(*arguments, **kwargs):
selfy = None
# Because we converted all kwargs to given into real args and
# error if we have neither args nor kwargs, this should always
# be valid
assert argspec.args
selfy = kwargs.get(argspec.args[0])
if isinstance(selfy, HypothesisProvided):
selfy = None
if selfy is not None:
setup_example = getattr(selfy, 'setup_example', None)
teardown_example = getattr(selfy, 'teardown_example', None)
else:
setup_example = None
teardown_example = None
setup_example = setup_example or (lambda: None)
teardown_example = teardown_example or (lambda ex: None)
if not any(
isinstance(x, HypothesisProvided)
for xs in (arguments, kwargs.values()) for x in xs):
# All arguments have been satisfied without needing to invoke
# hypothesis
setup_example()
try:
test(*arguments, **kwargs)
finally:
teardown_example((arguments, kwargs))
return
def convert_to_specifier(v):
if isinstance(v, HypothesisProvided):
return v.value
else:
return just(v)
given_specifier = (tuple(map(convert_to_specifier, arguments)), {
k: convert_to_specifier(v)
for k, v in kwargs.items()
})
def to_falsify(xs):
testargs, testkwargs = xs
try:
test(*testargs, **testkwargs)
return True
except UnsatisfiedAssumption as e:
raise e
except Exception: # pylint: disable=broad-except
return False
to_falsify.__name__ = test.__name__
to_falsify.__qualname__ = getattr(test, '__qualname__',
test.__name__)
if _debugging_return_failing_example.value:
return verifier.falsify(
to_falsify,
given_specifier,
setup_example=setup_example,
teardown_example=teardown_example,
)[0]
try:
falsifying_example = verifier.falsify(
to_falsify,
given_specifier,
setup_example=setup_example,
teardown_example=teardown_example,
)[0]
except Unfalsifiable:
return
try:
false_args, false_kwargs = falsifying_example
current_reporter()(
'Falsifying example: %s(%s)' %
(test.__name__, arg_string(
test,
false_args,
false_kwargs,
)))
# We run this one final time so we get good errors
# Otherwise we would have swallowed all the reports of it
# actually having gone wrong.
test(*false_args, **false_kwargs)
finally:
teardown_example(falsifying_example)
# If we get here then something has gone wrong: We found a counter
# example but it didn't fail when we invoked it again.
raise Flaky(test, falsifying_example)
wrapped_test.__name__ = test.__name__
wrapped_test.__doc__ = test.__doc__
wrapped_test.verifier = verifier
wrapped_test.is_hypothesis_test = True
return wrapped_test
return run_test_with_generator
def test_slow_failing_test_1(x):
time.sleep(0.05)
assert not calls[0]
calls[0] = 1
@fails
@given(int, settings=timeout_settings)
def test_slow_failing_test_2(x):
time.sleep(0.05)
assert not calls[1]
calls[1] = 1
@fails
@given(int, verifier=Verifier(settings=timeout_settings))
def test_slow_failing_test_3(x):
time.sleep(0.05)
assert not calls[2]
calls[2] = 1
@fails
@given(int, verifier=Verifier(settings=timeout_settings))
def test_slow_failing_test_4(x):
time.sleep(0.05)
assert not calls[3]
calls[3] = 1
@fails
def strategy_test_suite(specifier, max_examples=100, random=None):
settings = Settings(
database=None,
max_examples=max_examples,
average_list_length=2.0,
)
random = random or Random()
verifier = Verifier(settings=settings, random=random)
strat = strategy(specifier, settings)
specifier_test = given(TemplatesFor(specifier), settings=settings)
class ValidationSuite(TestCase):
def __repr__(self):
return 'strategy_test_suite(%s)' % (show(specifier), )
@given(specifier, settings=settings)
def test_does_not_error(self, value):
pass
def test_can_give_example(self):
strat.example()
@specifier_test
def test_is_basic(self, value):
def is_basic(v):
return isinstance(
v, integer_types + (list, type(None), text_type)) and (
not isinstance(v, list) or all(is_basic(w) for w in v))
supposedly_basic = strat.to_basic(value)
self.assertTrue(is_basic(supposedly_basic), repr(supposedly_basic))
@specifier_test
def test_can_round_trip_through_the_database(self, template):
empty_db = ExampleDatabase(backend=SQLiteBackend(':memory:'), )
try:
storage = empty_db.storage_for(specifier)
storage.save(template)
values = list(storage.fetch())
assert len(values) == 1
assert strat.to_basic(template) == strat.to_basic(values[0])
finally:
empty_db.close()
@specifier_test
def test_template_is_hashable(self, template):
hash(template)
@specifier_test
def test_can_minimize_to_empty(self, template):
simplest = list(strat.simplify_such_that(template,
lambda x: True))[-1]
assert list(strat.simplify(simplest)) == []
@given(Random, verifier=verifier)
def test_can_perform_all_basic_operations(self, random):
parameter = strat.draw_parameter(random)
template = strat.draw_template(BuildContext(random), parameter)
minimal_template = list(
strat.simplify_such_that(template, lambda x: True))[-1]
strat.reify(minimal_template)
assert (strat.to_basic(minimal_template) == strat.to_basic(
strat.from_basic(strat.to_basic(minimal_template))))
return ValidationSuite
def smallest_tree(predicate):
d = NAryTree(int, int, int)
strat = strategy(d)
v = Verifier()
return strat.reify(v.falsify(lambda t: not predicate(t), d)[0])
def smallest_tree(predicate):
d = NAryTree(int, int, int)
strat = strategy(d)
v = Verifier()
return strat.reify(v.falsify(lambda t: not predicate(t), d)[0])
def test_a_verifier_can_still_do_its_thing_if_a_saved_example_fails():
database = ExampleDatabase()
verifier = Verifier(settings=hs.Settings(database=database))
verifier.falsify(lambda x: x < 11, int)
verifier2 = Verifier(settings=hs.Settings(database=database))
verifier2.falsify(lambda x: x < 100, int)
def test_a_verifier_saves_any_failing_examples_in_its_database():
database = ExampleDatabase()
verifier = Verifier(settings=hs.Settings(database=database))
counterexample = verifier.falsify(lambda x: x > 0, int)
saved = list(database.storage_for((int, )).fetch())
assert saved == [counterexample]