def mutate(self) -> None:
"""Apply mutation at test suite level."""
assert self._test_case_factory, "Can only mutate with test case factory."
changed = False
# Mutate existing test cases.
for test in self._tests:
if randomness.next_float() < 1.0 / self.size():
test.mutate()
if test.has_changed():
changed = True
# Randomly add new test cases.
alpha = config.INSTANCE.test_insertion_probability
exponent = 1
while (randomness.next_float() <= pow(alpha, exponent)
and self.size() < config.INSTANCE.max_size):
self.add_test(self._test_case_factory.get_test_case())
exponent += 1
changed = True
# Remove any tests that have no more statements left.
self._tests = [t for t in self._tests if t.size() > 0]
if changed:
self.set_changed(True)
def mutate(self) -> None:
"""Each statement is mutated with probability 1/l."""
changed = False
if (config.INSTANCE.chop_max_length
and self.size() >= config.INSTANCE.chromosome_length):
last_mutatable_position = self._get_last_mutatable_statement()
if last_mutatable_position is not None:
self.chop(last_mutatable_position)
changed = True
if randomness.next_float() <= config.INSTANCE.test_delete_probability:
if self._mutation_delete():
changed = True
if randomness.next_float() <= config.INSTANCE.test_change_probability:
if self._mutation_change():
changed = True
if randomness.next_float() <= config.INSTANCE.test_insert_probability:
if self._mutation_insert():
changed = True
if changed:
self.set_changed(True)
def mutate(self) -> None:
"""Apply mutation at test suite level."""
assert (
self._test_case_chromosome_factory is not None
), "Mutation is not possibly without test case chromosome factory"
changed = False
# Mutate existing test cases.
for test in self._test_case_chromosomes:
if randomness.next_float() < 1.0 / self.size():
test.mutate()
if test.has_changed():
changed = True
# Randomly add new test cases.
alpha = config.configuration.test_insertion_probability
exponent = 1
while (randomness.next_float() <= pow(alpha, exponent)
and self.size() < config.configuration.max_size):
self.add_test_case_chromosome(
self._test_case_chromosome_factory.get_chromosome())
exponent += 1
changed = True
# Remove any tests that have no more statements left.
self._test_case_chromosomes = [
t for t in self._test_case_chromosomes if t.size() > 0
]
if changed:
self.set_changed(True)
def mutate(self) -> None:
changed = False
if (config.configuration.chop_max_length
and self.size() >= config.configuration.chromosome_length):
last_mutatable_position = self.get_last_mutatable_statement()
if last_mutatable_position is not None:
self._test_case.chop(last_mutatable_position)
changed = True
# In case mutation removes all calls on the SUT.
backup = self.test_case.clone()
if randomness.next_float(
) <= config.configuration.test_delete_probability:
if self._mutation_delete():
changed = True
if randomness.next_float(
) <= config.configuration.test_change_probability:
if self._mutation_change():
changed = True
if randomness.next_float(
) <= config.configuration.test_insert_probability:
if self._mutation_insert():
changed = True
assert self._test_factory, "Required for mutation"
if not self._test_factory.has_call_on_sut(self._test_case):
self._test_case = backup
self._mutation_insert()
if changed:
self.set_changed(True)
def _mutate_parameters(self, p_per_param: float) -> bool:
"""
Mutates args and kwargs with the given probability.
:param p_per_param: The probability for one parameter to be mutated.
"""
changed = False
for arg in range(len(self.args)):
if randomness.next_float() < p_per_param:
changed |= self._mutate_parameter(arg)
for kwarg in self.kwargs.keys():
if randomness.next_float() < p_per_param:
changed |= self._mutate_parameter(kwarg)
return changed
def delta(self) -> None:
assert self._value is not None
working_on = list(self._value)
p_perform_action = 1.0 / 3.0
if randomness.next_float() < p_perform_action and len(working_on) > 0:
working_on = self._random_deletion(working_on)
if randomness.next_float() < p_perform_action and len(working_on) > 0:
working_on = self._random_replacement(working_on)
if randomness.next_float() < p_perform_action:
working_on = self._random_insertion(working_on)
self._value = "".join(working_on)
def _random_replacement(working_on: List[str]) -> List[str]:
p_per_char = 1.0 / len(working_on)
return [
randomness.next_char()
if randomness.next_float() < p_per_char else char
for char in working_on
]
def insert_random_statement(self, test_case: tc.TestCase,
last_position: int) -> int:
"""Insert a random statement up to the given position.
If the insertion was successful, the position at which the statement was inserted
is returned, otherwise -1.
Args:
test_case: The test case to add the statement to
last_position: The last position before that the statement is inserted
Returns:
The index the statement was inserted to, otherwise -1
"""
old_size = test_case.size()
rand = randomness.next_float()
position = randomness.next_int(0, last_position + 1)
if rand <= config.INSTANCE.insertion_uut:
success = self.insert_random_call(test_case, position)
else:
success = self.insert_random_call_on_object(test_case, position)
if test_case.size() - old_size > 1:
position += test_case.size() - old_size - 1
if success:
return position
return -1
def _mutation_insert(self) -> bool:
"""With exponentially decreasing probability, insert statements at a
random position.
Returns:
Whether or not the test case was changed
"""
changed = False
alpha = config.configuration.statement_insertion_probability
exponent = 1
while (randomness.next_float() <= pow(alpha, exponent)
and self.size() < config.configuration.chromosome_length):
assert self._test_factory, "Mutation requires a test factory."
max_position = self.get_last_mutatable_statement()
if max_position is None:
# No mutatable statement found, so start at the first position.
max_position = 0
else:
# Also include the position after the last mutatable statement.
max_position += 1
position = self._test_factory.insert_random_statement(
self._test_case, max_position)
exponent += 1
if 0 <= position < self.size():
changed = True
return changed
def _get_variable_fallback(
self,
test_case: tc.TestCase,
parameter_type: Optional[Type],
position: int,
recursion_depth: int,
allow_none: bool,
) -> Optional[vr.VariableReference]:
"""Best effort approach to return some kind of matching variable."""
objects = test_case.get_objects(parameter_type, position)
# No objects to choose from, so either create random type variable or use None.
if not objects:
if config.INSTANCE.guess_unknown_types and randomness.next_float(
) <= 0.85:
return self._create_random_type_variable(
test_case, position, recursion_depth, allow_none)
if allow_none:
return self._create_none(test_case, parameter_type, position,
recursion_depth)
raise ConstructionFailedException(
f"No objects for type {parameter_type}")
# Could not create, so re-use an existing variable.
self._logger.debug("Choosing from %d existing objects: %s",
len(objects), objects)
reference = randomness.choice(objects)
self._logger.debug("Use existing object of type %s: %s",
parameter_type, reference)
return reference
def _attempt_generation(
self,
test_case: tc.TestCase,
parameter_type: Optional[Type],
position: int,
recursion_depth: int,
allow_none: bool,
exclude: Optional[vr.VariableReference] = None,
) -> Optional[vr.VariableReference]:
# We only select a concrete type e.g. from a union, when we are forced to choose one.
parameter_type = self._test_cluster.select_concrete_type(
parameter_type)
if not parameter_type:
return None
if allow_none and randomness.next_float(
) <= config.INSTANCE.none_probability:
return self._create_none(test_case, parameter_type, position,
recursion_depth)
if is_primitive_type(parameter_type):
return self._create_primitive(
test_case,
parameter_type,
position,
recursion_depth,
)
if type_generators := self._test_cluster.get_generators_for(
parameter_type):
return self._attempt_generation_for_type(test_case, position,
recursion_depth,
allow_none,
type_generators)
def _random_insertion(self) -> bool:
changed = False
pos = 0
if len(self._elements) > 0:
pos = randomness.next_int(0, len(self._elements) + 1)
# This is so ugly...
key_type = (get_args(self.ret_val.variable_type)[0]
if get_args(self.ret_val.variable_type) else None)
val_type = (get_args(self.ret_val.variable_type)[1]
if get_args(self.ret_val.variable_type) else None)
possibles_keys = self.test_case.get_objects(key_type,
self.get_position())
possibles_values = self.test_case.get_objects(val_type,
self.get_position())
alpha = 0.5
exponent = 1
while randomness.next_float() <= pow(alpha, exponent):
exponent += 1
if len(possibles_keys) > 0 and len(possibles_values) > 0:
self._elements.insert(
pos,
(
randomness.choice(possibles_keys),
randomness.choice(possibles_values),
),
)
changed = True
return changed
def mutate(self) -> bool:
changed = False
if (randomness.next_float() <
config.Configuration.test_delete_probability
and len(self._elements) > 0):
changed |= self._random_deletion()
if (randomness.next_float() <
config.Configuration.test_change_probability
and len(self._elements) > 0):
changed |= self._random_replacement()
if randomness.next_float(
) < config.Configuration.test_insert_probability:
changed |= self._random_insertion()
return changed
def randomize_value(self) -> None:
if (config.INSTANCE.constant_seeding
and StaticConstantSeeding().has_ints
and randomness.next_float() <= 0.90):
self._value = StaticConstantSeeding().random_int
else:
self._value = int(randomness.next_gaussian() *
config.INSTANCE.max_int)
def _random_deletion(self) -> bool:
p_per_element = 1.0 / len(self._elements)
previous_length = len(self._elements)
self._elements = [
element for element in self._elements
if randomness.next_float() >= p_per_element
]
return previous_length != len(self._elements)
def randomize_value(self) -> None:
if (config.INSTANCE.constant_seeding
and StaticConstantSeeding().has_strings
and randomness.next_float() <= 0.90):
self._value = StaticConstantSeeding().random_string
else:
length = randomness.next_int(0, config.INSTANCE.string_length + 1)
self._value = randomness.next_string(length)
def randomize_value(self) -> None:
if (config.INSTANCE.constant_seeding
and StaticConstantSeeding().has_floats
and randomness.next_float() <= 0.90):
self._value = StaticConstantSeeding().random_float
else:
val = randomness.next_gaussian() * config.INSTANCE.max_int
precision = randomness.next_int(0, 7)
self._value = round(val, precision)
def delta(self) -> None:
assert self._value is not None
probability = randomness.next_float()
if probability < 1.0 / 3.0:
self._value += randomness.next_gaussian() * config.INSTANCE.max_delta
elif probability < 2.0 / 3.0:
self._value += randomness.next_gaussian()
else:
self._value = round(self._value, randomness.next_int(0, 7))
def get_test_case(self) -> tc.TestCase:
if (
config.configuration.initial_population_seeding
and initpopseeding.initialpopulationseeding.has_tests
and randomness.next_float()
<= config.configuration.seeded_testcases_reuse_probability
):
return initpopseeding.initialpopulationseeding.seeded_testcase
return self._delegate.get_test_case()
def cross_over(self, parent1: T, parent2: T):
if parent1.size() < 2 or parent2.size() < 2:
return
split_point = randomness.next_float()
position1 = floor((parent1.size() - 1) * split_point) + 1
position2 = floor((parent2.size() - 1) * split_point) + 1
clone1 = parent1.clone()
clone2 = parent2.clone()
parent1.cross_over(clone2, position1, position2)
parent2.cross_over(clone1, position2, position1)
def get_index(self, population: List[T]) -> int:
"""Provides an index in the population that is chosen by rank selection.
Make sure that the population is sorted. The fittest chromosomes have to
come first."""
random_value = randomness.next_float()
bias = config.INSTANCE.rank_bias
return int(
len(population) *
((bias - sqrt(bias**2 - (4.0 *
(bias - 1.0) * random_value))) / 2.0 /
(bias - 1.0)))
def _random_replacement(self) -> bool:
p_per_element = 1.0 / len(self._elements)
changed = False
for i, elem in enumerate(self._elements):
if randomness.next_float() < p_per_element:
# TODO(fk) what if the current type is not correct?
replace = randomness.choice(
self.test_case.get_objects(elem.variable_type,
self.get_position()) + [elem])
self._elements[i] = replace
changed |= replace != elem
return changed
def mutate(self) -> bool:
if randomness.next_float(
) >= config.INSTANCE.change_parameter_probability:
return False
objects = self.test_case.get_objects(self.source.variable_type,
self.get_position())
objects.remove(self.source)
if len(objects) > 0:
self.source = randomness.choice(objects)
return True
return False
def mutate(self) -> bool:
if randomness.next_float(
) >= config.INSTANCE.change_parameter_probability:
return False
changed = False
mutable_param_count = self._mutable_argument_count()
if mutable_param_count > 0:
p_per_param = 1.0 / mutable_param_count
changed |= self._mutate_special_parameters(p_per_param)
changed |= self._mutate_parameters(p_per_param)
return changed
def _random_insertion(working_on: List[str]) -> List[str]:
pos = 0
if len(working_on) > 0:
pos = randomness.next_int(0, len(working_on) + 1)
alpha = 0.5
exponent = 1
while (randomness.next_float() <= pow(alpha, exponent)
and len(working_on) < config.INSTANCE.string_length):
exponent += 1
working_on = working_on[:pos] + [randomness.next_char()
] + working_on[pos:]
return working_on
def _mutate_special_parameters(self, p_per_param: float) -> bool:
# We mutate the callee here, as the special parameter.
if randomness.next_float() < p_per_param:
callee = self.callee
objects = self.test_case.get_objects(callee.variable_type,
self.get_position())
objects.remove(callee)
if len(objects) > 0:
self.callee = randomness.choice(objects)
return True
return False
def _random_insertion(working_on: List[int]) -> List[int]:
pos = 0
if len(working_on) > 0:
pos = randomness.next_int(0, len(working_on) + 1)
alpha = 0.5
exponent = 1
while (
randomness.next_float() <= pow(alpha, exponent)
and len(working_on) < config.configuration.bytes_length
):
exponent += 1
working_on = working_on[:pos] + [randomness.next_byte()] + working_on[pos:]
return working_on
def _mutation_delete(self) -> bool:
last_mutatable_statement = self._get_last_mutatable_statement()
if last_mutatable_statement is None:
return False
changed = False
p_per_statement = 1.0 / (last_mutatable_statement + 1)
for idx in reversed(range(last_mutatable_statement + 1)):
if idx >= self.size():
continue
if randomness.next_float() <= p_per_statement:
changed |= self._delete_statement(idx)
return changed
def randomize_value(self) -> None:
use_seed = (
randomness.next_float()
<= config.configuration.seeded_primitives_reuse_probability
)
if (
config.configuration.dynamic_constant_seeding
and dynamic_constant_seeding.has_ints
and use_seed
and config.configuration.constant_seeding
and randomness.next_float()
<= config.configuration.seeded_dynamic_values_reuse_probability
):
self._value = dynamic_constant_seeding.random_int
elif (
config.configuration.constant_seeding
and static_constant_seeding.has_ints
and use_seed
):
self._value = static_constant_seeding.random_int
else:
self._value = int(randomness.next_gaussian() * config.configuration.max_int)
def evolve(self) -> None:
"""Evolve the current population and replace it with a new one."""
new_generation = []
new_generation.extend(self.elitism())
while not self.is_next_population_full(new_generation):
parent1 = self._selection_function.select(self._population, 1)[0]
parent2 = self._selection_function.select(self._population, 1)[0]
offspring1 = parent1.clone()
offspring2 = parent2.clone()
try:
if randomness.next_float() <= config.INSTANCE.crossover_rate:
self._crossover_function.cross_over(offspring1, offspring2)
offspring1.mutate()
offspring2.mutate()
except ConstructionFailedException as ex:
self._logger.info("Crossover/Mutation failed: %s", ex)
continue
fitness_parents = min(parent1.get_fitness(), parent2.get_fitness())
fitness_offspring = min(offspring1.get_fitness(), offspring2.get_fitness())
length_parents = (
parent1.total_length_of_test_cases + parent2.total_length_of_test_cases
)
length_offspring = (
offspring1.total_length_of_test_cases
+ offspring2.total_length_of_test_cases
)
best_individual = self._get_best_individual()
if (fitness_offspring < fitness_parents) or (
fitness_offspring == fitness_parents
and length_offspring <= length_parents
):
for offspring in [offspring1, offspring2]:
if (
offspring.total_length_of_test_cases
<= 2 * best_individual.total_length_of_test_cases
):
new_generation.append(offspring)
else:
new_generation.append(randomness.choice([parent1, parent2]))
else:
new_generation.append(parent1)
new_generation.append(parent2)
self._population = new_generation
self._sort_population()
StatisticsTracker().current_individual(self._get_best_individual())
