'If depends on past isn\'t set in the task then the previous dagrun should be
ignored, even though there is no previous_ti which would normally fail the dep'

def test_not_depends_on_past(self):

    task = self._get_task(depends_on_past=False, start_date=datetime(2016, 1, 1), wait_for_downstream=False)
    prev_ti = Mock(task=task, state=State.SUCCESS, are_dependents_done=Mock(return_value=True), execution_date=datetime(2016, 1, 2))
    ti = Mock(task=task, previous_ti=prev_ti, execution_date=datetime(2016, 1, 3))
    dep_context = DepContext(ignore_depends_on_past=False)
    self.assertTrue(PrevDagrunDep().is_met(ti=ti, dep_context=dep_context))
