def get_spec(self):
spec = Specification('sample')
spec.add_variable(Variable('set', '[int]bool', 1))
procedure = Procedure('merge_6', 15)
procedure.add_parameter(Parameter('set1', '[int]bool'))
procedure.add_modifies('set')
procedure.add_ensures(
'(forall i:int :: set[i] == (old(set)[i] || set1[i]))')
procedure.set_implementation('assume false;')
spec.set_merge(procedure)
gteq = Function('gteq', 5)
gteq.add_param(Parameter('set1', '[int]bool'))
gteq.add_param(Parameter('set2', '[int]bool'))
gteq.set_return('bool')
spec.set_gteq(gteq)
spec.set_preface(
'var set:[int]bool;\n//@gteq\nfunction gteq(set1:[int]bool, set2:[int]bool) returns(bool)\n{(forall i:int :: set2[i] ==> set1[i])}'
)
procedure = Procedure('add', 15)
procedure.add_parameter(Parameter('value', 'int'))
procedure.add_modifies('set')
procedure.add_ensures(
'(forall i:int :: (i == value ==> set[i] == true) && (i != value ==> set[i] == old(set)[i]))'
)
procedure.set_implementation('set[value] := true;')
spec.add_procedure(procedure)
return spec
def extract_function(self, spec, position):
spec_text = ''.join(spec)
semi_colon_index = spec_text.index(';')
bracket_index = spec_text.index('{')
function_end = min(semi_colon_index, bracket_index)
function_text = spec_text[:function_end].strip()
fun_name = function_text[9:function_text.index('(')].strip()
function = Function(fun_name, position)
param_spec = function_text[function_text.index('(') +
1:function_text.index(')')].strip()
for each in self.__get_params(param_spec):
function.add_param(each)
returndt = self.__get_returndt(function_text)
function.set_return(returndt)
if bracket_index > 1:
implementation = spec_text[bracket_index +
1:spec_text.index('}')].strip()
function.implementation = implementation
return function
def test_check_not_monotonicity(self):
spec = Specification('sample')
spec.add_variable(Variable('set', '[int]bool', 1))
procedure = Procedure('remove', 15)
procedure.add_parameter(Parameter('value', 'int'))
procedure.add_modifies('set')
procedure.set_implementation('set[value] := false;')
spec.add_procedure(procedure)
gteq = Function('gteq', 5)
gteq.add_param(Parameter('one', '[int]bool'))
gteq.add_param(Parameter('two', '[int]bool'))
gteq.set_return('bool')
spec.set_gteq(gteq)
spec.set_preface(
'var set:[int]bool;\n//@gteq\nfunction gteq(set1:[int]bool, set2:[int]bool) returns(bool)\n{(forall i:int :: set2[i] ==> set1[i])}'
)
checker = ConvergenceChecker()
with pytest.raises(ConvergenceError):
checker.check_monotonicity(spec, procedure)
def test_check_lub(self):
spec = Specification('sample')
spec.add_variable(Variable('set', '[int]bool', 1))
procedure = Procedure('merge_6', 15)
procedure.add_parameter(Parameter('set1', '[int]bool'))
procedure.add_modifies('set')
procedure.add_ensures(
'(forall i:int :: set[i] == (old(set)[i] || set1[i]))')
procedure.set_implementation('assume false;')
spec.set_merge(procedure)
gteq = Function('gteq', 5)
gteq.add_param(Parameter('set1', '[int]bool'))
gteq.add_param(Parameter('set2', '[int]bool'))
gteq.set_return('bool')
spec.set_gteq(gteq)
spec.set_preface(
'var set:[int]bool;\n//@gteq\nfunction gteq(set1:[int]bool, set2:[int]bool) returns(bool)\n{(forall i:int :: set2[i] ==> set1[i])}'
)
checker = ConvergenceChecker()
assert checker.check_lub(spec) == True
def test_stable_pair(self):
spec = Specification('sample')
spec.add_variable(Variable('counter', 'int', 1))
procedure = Procedure('inc', 15)
procedure.add_parameter(Parameter('value', 'int'))
procedure.add_modifies('counter')
procedure.add_requires('value > 0')
procedure.set_implementation('counter := counter + value;')
spec.add_procedure(procedure)
merge = Procedure('merge', 15)
merge.add_parameter(Parameter('counter1', 'int'))
merge.add_modifies('counter')
merge.set_implementation('counter := (if counter1 > counter then counter1 else counter);')
spec.set_merge(merge)
invariant = Function('inv', 10)
invariant.add_param(Parameter('counter', 'int'))
invariant.set_return('bool')
spec.set_invariant(invariant)
spec.set_preface('var counter :int;\n//@invariant\nfunction inv(counter:int) returns(bool)\n{\n counter >= 0\n}')
checker = SafetyChecker()
assert checker.check_stability(spec, procedure) == True
def test_unsafe_proc(self):
spec = Specification('sample')
spec.add_variable(Variable('counter', 'int', 1))
procedure = Procedure('dec', 15)
procedure.add_parameter(Parameter('value', 'int'))
procedure.add_modifies('counter')
procedure.set_implementation('counter := counter - value;')
spec.add_procedure(procedure)
merge = Procedure('merge', 15)
merge.add_parameter(Parameter('counter1', 'int'))
merge.add_modifies('counter')
merge.set_implementation('counter := (if counter1 > counter then counter1 else counter);')
spec.set_merge(merge)
invariant = Function('inv', 10)
invariant.add_param(Parameter('counter', 'int'))
invariant.set_return('bool')
spec.set_invariant(invariant)
spec.set_preface('var counter :int;\n//@invariant\nfunction inv(counter:int) returns(bool)\n{\n counter >= 0\n}')
checker = SafetyChecker()
with pytest.raises(SafetyError):
checker.check_safety(spec, procedure)
def test_check_monotonicity(self):
spec = Specification('sample')
spec.add_variable(Variable('set', '[int]bool', 1))
procedure = Procedure('add', 15)
procedure.add_parameter(Parameter('value', 'int'))
procedure.add_modifies('set')
procedure.add_ensures(
'(forall i:int :: (i == value ==> set[i] == true) && (i != value ==> set[i] == old(set)[i]))'
)
procedure.set_implementation('set[value] := true;')
spec.add_procedure(procedure)
gteq = Function('gteq', 5)
gteq.add_param(Parameter('set1', '[int]bool'))
gteq.add_param(Parameter('set2', '[int]bool'))
gteq.set_return('bool')
spec.set_gteq(gteq)
spec.set_preface(
'var set:[int]bool;\n//@gteq\nfunction gteq(set1:[int]bool, set2:[int]bool) returns(bool)\n{(forall i:int :: set2[i] ==> set1[i])}'
)
checker = ConvergenceChecker()
assert checker.check_monotonicity(spec, procedure) == True