def build_chooser(stream):
index = [-1]
choice_count = [0]
context = current_build_context()
context.mark_captured()
def choice(values):
if not values:
raise IndexError('Cannot choose from empty sequence')
k = len(values) - 1
if k == 0:
chosen = 0
else:
mask = _right_saturate(k)
while True:
index[0] += 1
probe = stream[index[0]] & mask
if probe <= k:
chosen = probe
break
choice_count[0] += 1
result = values[chosen]
with context.local():
note('Choice #%d: %r' % (choice_count[0], result))
return result
return choice
def run_state_machine(factory, data):
machine = factory()
check_type(GenericStateMachine, machine, "state_machine_factory()")
data.conjecture_data.hypothesis_runner = machine
n_steps = settings.stateful_step_count
should_continue = cu.many(data.conjecture_data,
min_size=1,
max_size=n_steps,
average_size=n_steps)
print_steps = (current_build_context().is_final
or current_verbosity() >= Verbosity.debug)
try:
if print_steps:
machine.print_start()
machine.check_invariants()
while should_continue.more():
value = data.conjecture_data.draw(machine.steps())
if print_steps:
machine.print_step(value)
machine.execute_step(value)
machine.check_invariants()
finally:
if print_steps:
machine.print_end()
machine.teardown()
def build_chooser(stream):
index = [-1]
choice_count = [0]
context = current_build_context()
context.mark_captured()
def choice(values):
if not values:
raise IndexError('Cannot choose from empty sequence')
k = len(values) - 1
if k == 0:
chosen = 0
else:
mask = _right_saturate(k)
while True:
index[0] += 1
probe = stream[index[0]] & mask
if probe <= k:
chosen = probe
break
choice_count[0] += 1
result = values[chosen]
with context.local():
note('Choice #%d: %r' % (choice_count[0], result))
return result
return choice
def run_state_machine(factory, data):
machine = factory()
check_type(GenericStateMachine, machine, "state_machine_factory()")
data.conjecture_data.hypothesis_runner = machine
n_steps = settings.stateful_step_count
should_continue = cu.many(
data.conjecture_data, min_size=1, max_size=n_steps, average_size=n_steps
)
print_steps = (
current_build_context().is_final or current_verbosity() >= Verbosity.debug
)
try:
if print_steps:
machine.print_start()
machine.check_invariants()
while should_continue.more():
value = data.conjecture_data.draw(machine.steps())
if print_steps:
machine.print_step(value)
machine.execute_step(value)
machine.check_invariants()
finally:
if print_steps:
machine.print_end()
machine.teardown()
def reify(self, template):
context = current_build_context()
context.mark_captured()
def do_reify(t):
with context.local():
return self.source_strategy.reify(t)
return template.stream.map(do_reify)
def reify(self, template):
context = current_build_context()
context.mark_captured()
def do_reify(t):
with context.local():
return self.source_strategy.reify(t)
return template.stream.map(do_reify)
def reify(self, value):
context = current_build_context()
if not hasattr(context, SHARED_STRATEGY_ATTRIBUTE):
setattr(context, SHARED_STRATEGY_ATTRIBUTE, {})
sharing = getattr(context, SHARED_STRATEGY_ATTRIBUTE)
key = self.key or self
if key in sharing:
value.used = False
else:
value.used = True
sharing[key] = self.base.reify(value.base)
return sharing[key]
def reify(self, value):
context = current_build_context()
if not hasattr(context, SHARED_STRATEGY_ATTRIBUTE):
setattr(context, SHARED_STRATEGY_ATTRIBUTE, {})
sharing = getattr(context, SHARED_STRATEGY_ATTRIBUTE)
key = self.key or self
if key in sharing:
value.used = False
else:
value.used = True
sharing[key] = self.base.reify(value.base)
return sharing[key]
def run_state_machine(factory, data):
machine = factory()
if isinstance(machine, GenericStateMachine) and not isinstance(
machine, RuleBasedStateMachine):
note_deprecation(
"%s inherits from GenericStateMachine, which is deprecated. Use a "
"RuleBasedStateMachine, or a test function with st.data(), instead."
% (type(machine).__name__, ),
since="2019-05-29",
)
else:
check_type(RuleBasedStateMachine, machine,
"state_machine_factory()")
data.conjecture_data.hypothesis_runner = machine
n_steps = settings.stateful_step_count
should_continue = cu.many(data.conjecture_data,
min_size=1,
max_size=n_steps,
average_size=n_steps)
print_steps = (current_build_context().is_final
or current_verbosity() >= Verbosity.debug)
try:
if print_steps:
machine.print_start()
machine.check_invariants()
while should_continue.more():
value = data.conjecture_data.draw(machine.steps())
# Assign 'result' here in case 'execute_step' fails below
result = multiple()
try:
result = machine.execute_step(value)
finally:
if print_steps:
# 'result' is only used if the step has target bundles.
# If it does, and the result is a 'MultipleResult',
# then 'print_step' prints a multi-variable assignment.
machine.print_step(value, result)
machine.check_invariants()
finally:
if print_steps:
machine.print_end()
machine.teardown()
def check_invariants(self, settings):
for invar in self.invariants():
if self._initialize_rules_to_run and not invar.check_during_init:
continue
if not all(precond(self) for precond in invar.preconditions):
continue
if (current_build_context().is_final
or settings.verbosity >= Verbosity.debug):
report(f"state.{invar.function.__name__}()")
result = invar.function(self)
if result is not None:
fail_health_check(
settings,
"The return value of an @invariant is always ignored, but "
f"{invar.function.__qualname__} returned {result!r} "
"instead of None",
HealthCheck.return_value,
)
def run_state_machine(factory, data):
machine = factory()
if isinstance(machine, GenericStateMachine) and not isinstance(
machine, RuleBasedStateMachine
):
note_deprecation(
"%s inherits from GenericStateMachine, which is deprecated. Use a "
"RuleBasedStateMachine, or a test function with st.data(), instead."
% (type(machine).__name__,),
since="2019-05-29",
)
else:
check_type(RuleBasedStateMachine, machine, "state_machine_factory()")
data.conjecture_data.hypothesis_runner = machine
n_steps = settings.stateful_step_count
should_continue = cu.many(
data.conjecture_data, min_size=1, max_size=n_steps, average_size=n_steps
)
print_steps = (
current_build_context().is_final or current_verbosity() >= Verbosity.debug
)
try:
if print_steps:
machine.print_start()
machine.check_invariants()
while should_continue.more():
value = data.conjecture_data.draw(machine.steps())
if print_steps:
machine.print_step(value)
machine.execute_step(value)
machine.check_invariants()
finally:
if print_steps:
machine.print_end()
machine.teardown()
def test_current_build_context_is_current():
with bc() as a:
assert current_build_context() is a
def test_raises_if_current_build_context_out_of_context():
with pytest.raises(InvalidArgument):
current_build_context()
def do_draw(self, data):
return Chooser(current_build_context(), data)
def test_current_build_context_is_current():
with bc() as a:
assert current_build_context() is a
def test_raises_if_current_build_context_out_of_context():
with pytest.raises(InvalidArgument):
current_build_context()
def execute_step(self, step):
assert current_build_context().is_final
def run_state_machine(factory, data):
machine = factory()
if not isinstance(machine, _GenericStateMachine):
raise InvalidArgument(
"Expected RuleBasedStateMachine but state_machine_factory() "
"returned %r (type=%s)" % (machine, type(machine).__name__))
data.conjecture_data.hypothesis_runner = machine
print_steps = (current_build_context().is_final
or current_verbosity() >= Verbosity.debug)
try:
if print_steps:
machine.print_start()
machine.check_invariants()
max_steps = settings.stateful_step_count
steps_run = 0
cd = data.conjecture_data
while True:
# We basically always want to run the maximum number of steps,
# but need to leave a small probability of terminating early
# in order to allow for reducing the number of steps once we
# find a failing test case, so we stop with probability of
# 2 ** -16 during normal operation but force a stop when we've
# generated enough steps.
cd.start_example(STATE_MACHINE_RUN_LABEL)
if steps_run == 0:
cd.draw_bits(16, forced=1)
elif steps_run >= max_steps:
cd.draw_bits(16, forced=0)
break
else:
# All we really care about is whether this value is zero
# or non-zero, so if it's > 1 we discard it and insert a
# replacement value after
cd.start_example(SHOULD_CONTINUE_LABEL)
should_continue_value = cd.draw_bits(16)
if should_continue_value > 1:
cd.stop_example(discard=True)
cd.draw_bits(16,
forced=int(bool(should_continue_value)))
else:
cd.stop_example()
if should_continue_value == 0:
break
steps_run += 1
value = data.conjecture_data.draw(machine.steps())
# Assign 'result' here in case 'execute_step' fails below
result = multiple()
try:
result = machine.execute_step(value)
finally:
if print_steps:
# 'result' is only used if the step has target bundles.
# If it does, and the result is a 'MultipleResult',
# then 'print_step' prints a multi-variable assignment.
machine.print_step(value, result)
machine.check_invariants()
data.conjecture_data.stop_example()
finally:
if print_steps:
machine.print_end()
machine.teardown()
def execute_step(self, step):
cb = current_build_context()
if not cb.is_final:
assert 0 not in bytearray(step)
def execute_step(self, step):
cb = current_build_context()
if not cb.is_final:
assert 0 not in bytearray(step)
def execute_step(self, step):
assert current_build_context().is_final
def steps(self):
cb = current_build_context()
if cb.is_final:
return binary(min_size=1, max_size=1)
else:
return binary(min_size=1024, max_size=1024)
def action(self, d):
if current_build_context().is_final:
d.draw(binary(min_size=1, max_size=1))
else:
buffer = binary(min_size=1024, max_size=1024)
assert 0 not in buffer
def steps(self):
cb = current_build_context()
if cb.is_final:
return binary(min_size=1, max_size=1)
else:
return binary(min_size=1024, max_size=1024)
def action(self):
assert current_build_context().is_final
def run_state_machine(factory, data):
cd = data.conjecture_data
machine = factory()
check_type(RuleBasedStateMachine, machine, "state_machine_factory()")
cd.hypothesis_runner = machine
print_steps = (current_build_context().is_final
or current_verbosity() >= Verbosity.debug)
try:
if print_steps:
report("state = %s()" % (machine.__class__.__name__, ))
machine.check_invariants()
max_steps = settings.stateful_step_count
steps_run = 0
while True:
# We basically always want to run the maximum number of steps,
# but need to leave a small probability of terminating early
# in order to allow for reducing the number of steps once we
# find a failing test case, so we stop with probability of
# 2 ** -16 during normal operation but force a stop when we've
# generated enough steps.
cd.start_example(STATE_MACHINE_RUN_LABEL)
if steps_run == 0:
cd.draw_bits(16, forced=1)
elif steps_run >= max_steps:
cd.draw_bits(16, forced=0)
break
else:
# All we really care about is whether this value is zero
# or non-zero, so if it's > 1 we discard it and insert a
# replacement value after
cd.start_example(SHOULD_CONTINUE_LABEL)
should_continue_value = cd.draw_bits(16)
if should_continue_value > 1:
cd.stop_example(discard=True)
cd.draw_bits(16,
forced=int(bool(should_continue_value)))
else:
cd.stop_example()
if should_continue_value == 0:
break
steps_run += 1
# Choose a rule to run, preferring an initialize rule if there are
# any which have not been run yet.
if machine._initialize_rules_to_run:
init_rules = [
st.tuples(st.just(rule),
st.fixed_dictionaries(rule.arguments))
for rule in machine._initialize_rules_to_run
]
rule, data = cd.draw(st.one_of(init_rules))
machine._initialize_rules_to_run.remove(rule)
else:
rule, data = cd.draw(machine._rules_strategy)
# Pretty-print the values this rule was called with *before* calling
# _add_result_to_targets, to avoid printing arguments which are also
# a return value using the variable name they are assigned to.
# See https://github.com/HypothesisWorks/hypothesis/issues/2341
if print_steps:
data_to_print = {
k: machine._pretty_print(v)
for k, v in data.items()
}
# Assign 'result' here in case executing the rule fails below
result = multiple()
try:
data = dict(data)
for k, v in list(data.items()):
if isinstance(v, VarReference):
data[k] = machine.names_to_values[v.name]
result = rule.function(machine, **data)
if rule.targets:
if isinstance(result, MultipleResults):
for single_result in result.values:
machine._add_result_to_targets(
rule.targets, single_result)
else:
machine._add_result_to_targets(
rule.targets, result)
finally:
if print_steps:
# 'result' is only used if the step has target bundles.
# If it does, and the result is a 'MultipleResult',
# then 'print_step' prints a multi-variable assignment.
machine._print_step(rule, data_to_print, result)
machine.check_invariants()
cd.stop_example()
finally:
if print_steps:
report("state.teardown()")
machine.teardown()
def do_draw(self, data):
return Chooser(current_build_context(), data)
