def test_cycle_check_yields_false_for_no_cycles(self):
# given
t1 = Task('t1')
t2 = Task('t2')
t1.dependants.append(t2)
# expect
self.assertFalse(t1.contains_dependency_cycle())
self.assertFalse(t2.contains_dependency_cycle())
def test_cycle_check_yields_false_for_trees(self):
# given
t1 = Task('t1')
t2 = Task('t2')
t3 = Task('t3')
t4 = Task('t4')
t1.dependants.append(t2)
t1.dependants.append(t3)
t2.dependants.append(t4)
t3.dependants.append(t4)
# expect
self.assertFalse(t1.contains_dependency_cycle())
self.assertFalse(t2.contains_dependency_cycle())
self.assertFalse(t3.contains_dependency_cycle())
self.assertFalse(t4.contains_dependency_cycle())
def test_cycle_check_yields_true_for_long_cycles(self):
# given
t1 = Task('t1')
t2 = Task('t2')
t3 = Task('t3')
t4 = Task('t4')
t5 = Task('t5')
t6 = Task('t6')
t1.dependants.append(t2)
t2.dependants.append(t3)
t3.dependants.append(t4)
t4.dependants.append(t5)
t5.dependants.append(t6)
t6.dependants.append(t1)
# expect
self.assertTrue(t1.contains_dependency_cycle())
self.assertTrue(t2.contains_dependency_cycle())
self.assertTrue(t3.contains_dependency_cycle())
self.assertTrue(t4.contains_dependency_cycle())
self.assertTrue(t5.contains_dependency_cycle())
self.assertTrue(t6.contains_dependency_cycle())
