def test_rule_has_consequence_when_false_different_field():
def condition(subject):
return subject['fruit'] == 'strawberry'
def consequence(subject):
subject['color'] = 'red'
rule = Rule('all strawberries are red', condition, consequence, {'fruit': 'strawberry'}, ('fruit',))
assert rule.has_consequence(condition) is False
def test_rule_has_consequence_when_true():
def condition(subject):
return subject['fruit'] == 'strawberry'
def consequence(subject):
subject['color'] = 'red'
rule = Rule('all strawberries are red', condition, consequence, {'fruit': 'strawberry'}, ('fruit',))
assert rule.has_consequence({'color': 'red'})
def test_rule_evaluate_returns_true_when_rule_pass():
def condition(subject):
return subject['fruit'] == 'strawberry'
def consequence(subject):
subject['color'] = 'red'
rule = Rule('all strawberries are red', condition, consequence, {'fruit': 'strawberry'}, ('fruit',))
assert rule.evaluate({'fruit': 'strawberry'})
def test_rule_evaluate_raise_error_when_applied_to_subject_without_rule_field():
def condition(subject):
return subject['fruit'] == 'strawberry'
def consequence(subject):
subject['color'] = 'red'
s = {}
rule = Rule('all strawberries are red', condition, consequence, {'fruit': 'strawberry'}, ('fruit',))
with pytest.raises(Rule.RuleNotApplyException):
rule.evaluate(s)
def test_rule_evaluate_does_not_apply_consequence_when_false():
def condition(subject):
return subject['fruit'] == 'strawberry'
def consequence(subject):
subject['color'] = 'red'
s = {'fruit': 'lime'}
rule = Rule('all strawberries are red', condition, consequence, {'fruit': 'strawberry'}, ('fruit',))
rule.evaluate(s)
assert s.get('color') is None
