def parse(self, spec_name, spec_text):
specification = Specification(spec_name)
import ipdb
preface = []
procedure_lines = []
for i, line in enumerate(spec_text):
if line.strip().startswith('@invariant'):
invariant = self.extract_function(spec_text[i + 1:], i + 2)
specification.set_invariant(invariant)
if line.strip().startswith('@gteq'):
gteq = self.extract_function(spec_text[i + 1:], i + 2)
specification.set_gteq(gteq)
if line.strip().startswith('@merge'):
end = self.get_end(spec_text[i + 1:], i + 1)
procedure_lines = procedure_lines + list(range(i + 1, end + 1))
merge = self.extract_procedure(spec_text[i + 1:end + 1], i + 1)
specification.set_merge(merge)
if line.strip().startswith('procedure ') and not spec_text[
i - 1].startswith('@merge'):
end = self.get_end(spec_text[i:], i)
procedure_lines = procedure_lines + list(range(i, end + 1))
procedure = self.extract_procedure(spec_text[i:end + 1], i)
specification.add_procedure(procedure)
if line.strip().startswith('@'):
preface.append('//' + line)
elif i in procedure_lines:
preface.append('//' + line)
else:
preface.append(line)
if line.strip().startswith('var ') and i not in procedure_lines:
variable = self.extract_variable(spec_text[i:], i + 1)
specification.add_variable(variable)
specification.set_preface(''.join(preface))
return specification
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 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_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