def test_reference_tasks():
x = Task("x")
y = Task("y")
z = Task("z")
f = Flow(name="test", tasks=[x, y, z])
f.set_reference_tasks([y])
assert f.reference_tasks() == {y}
f2 = FlowSchema().load(FlowSchema().dump(f))
assert f2.reference_tasks() == {t for t in f2.tasks if t.name == "y"}
def test_flow_run_state_determined_by_reference_tasks():
flow = Flow(name="test")
t1 = ErrorTask()
t2 = SuccessTask(trigger=prefect.triggers.all_finished)
flow.add_edge(t1, t2)
flow.set_reference_tasks([t1])
flow_state = flow.run()
assert isinstance(flow_state, Failed)
assert isinstance(flow_state.result[t1], Failed)
assert isinstance(flow_state.result[t2], Success)
def test_flow_run_state_not_determined_by_reference_tasks_if_terminal_tasks_are_not_finished():
flow = Flow(name="test")
t1 = ErrorTask()
t2 = RaiseRetryTask(trigger=prefect.triggers.all_finished)
flow.add_edge(t1, t2)
flow.set_reference_tasks([t1])
flow_state = FlowRunner(flow=flow).run(return_tasks=flow.tasks)
assert flow_state.is_running()
assert flow_state.result[t1].is_failed()
assert flow_state.result[t2].is_retrying()
def test_serialize_flow_sorts_nested_schemas():
a = Parameter("a", default=1)
b = Parameter("b", default=2)
c = Task("c")
d = Task("d")
f = Flow("test")
d.set_upstream(c, flow=f)
c.set_upstream(b, flow=f).set_upstream(a, flow=f)
f.set_reference_tasks([d, c])
# Must use `f.serialize` instead of `FlowSchema().dump` because task slugs
# are not guaranteed to be set yet
serialized = f.serialize()
assert [param["slug"] for param in serialized["parameters"]] == ["a", "b"]
assert [task["slug"] for task in serialized["tasks"]] == ["a", "b", "c-1", "d-1"]
assert [
(edge["upstream_task"]["slug"], edge["downstream_task"]["slug"])
for edge in serialized["edges"]
] == [("a", "c-1"), ("b", "c-1"), ("c-1", "d-1")]
assert [task["slug"] for task in serialized["reference_tasks"]] == ["c-1", "d-1"]
