import pkg/asynctest import pkg/questionable import pkg/chronos import pkg/upraises import codex/utils/asyncstatemachine import ../helpers/eventually type State1 = ref object of State State2 = ref object of State State3 = ref object of State State4 = ref object of State var runs, cancellations, errors = [0, 0, 0, 0] method `$`(state: State1): string = "State1" method `$`(state: State2): string = "State2" method `$`(state: State3): string = "State3" method `$`(state: State4): string = "State4" method run(state: State1, machine: Machine): Future[?State] {.async.} = inc runs[0] return some State(State2.new()) method run(state: State2, machine: Machine): Future[?State] {.async.} = inc runs[1] try: await sleepAsync(1.hours) except CancelledError: inc cancellations[1] raise method run(state: State3, machine: Machine): Future[?State] {.async.} = inc runs[2] method run(state: State4, machine: Machine): Future[?State] {.async.} = inc runs[3] raise newException(ValueError, "failed") method onMoveToNextStateEvent*(state: State): ?State {.base, upraises:[].} = discard method onMoveToNextStateEvent(state: State2): ?State = some State(State3.new()) method onMoveToNextStateEvent(state: State3): ?State = some State(State1.new()) method onError(state: State1, error: ref CatchableError): ?State = inc errors[0] method onError(state: State2, error: ref CatchableError): ?State = inc errors[1] method onError(state: State3, error: ref CatchableError): ?State = inc errors[2] method onError(state: State4, error: ref CatchableError): ?State = inc errors[3] some State(State2.new()) suite "async state machines": var machine: Machine proc moveToNextStateEvent(state: State): ?State = state.onMoveToNextStateEvent() setup: runs = [0, 0, 0, 0] cancellations = [0, 0, 0, 0] errors = [0, 0, 0, 0] machine = Machine.new() test "should call run on start state": machine.start(State1.new()) check eventually runs[0] == 1 test "moves to next state when run completes": machine.start(State1.new()) check eventually runs == [1, 1, 0, 0] test "state2 moves to state3 on event": machine.start(State2.new()) machine.schedule(moveToNextStateEvent) check eventually runs == [0, 1, 1, 0] test "state transition will cancel the running state": machine.start(State2.new()) machine.schedule(moveToNextStateEvent) check eventually cancellations == [0, 1, 0, 0] test "scheduled events are handled one after the other": machine.start(State2.new()) machine.schedule(moveToNextStateEvent) machine.schedule(moveToNextStateEvent) check eventually runs == [1, 2, 1, 0] test "stops scheduling and current state": machine.start(State2.new()) await sleepAsync(1.millis) machine.stop() machine.schedule(moveToNextStateEvent) await sleepAsync(1.millis) check runs == [0, 1, 0, 0] check cancellations == [0, 1, 0, 0] test "forwards errors to error handler": machine.start(State4.new()) check eventually errors == [0, 0, 0, 1] and runs == [0, 1, 0, 1] test "error handler ignores CancelledError": machine.start(State2.new()) machine.schedule(moveToNextStateEvent) check eventually cancellations == [0, 1, 0, 0] check errors == [0, 0, 0, 0] test "queries properties of the current state": proc description(state: State): string = $state machine.start(State2.new()) check eventually machine.query(description) == some "State2" machine.schedule(moveToNextStateEvent) check eventually machine.query(description) == some "State3" test "stops handling queries when stopped": proc description(state: State): string = $state machine.start(State2.new()) check eventually machine.query(description).isSome machine.stop() check machine.query(description).isNone