statelyai/xstate xstate@4.20.1

on GitHub

Patch Changes

• 99bc5fb9 #2275 Thanks @davidkpiano! - The SpawnedActorRef TypeScript interface has been deprecated in favor of a unified ActorRef interface, which contains the following:

  interface ActorRef<TEvent extends EventObject, TEmitted = any>
    extends Subscribable<TEmitted> {
    send: (event: TEvent) => void;
    id: string;
    subscribe(observer: Observer<T>): Subscription;
    subscribe(
      next: (value: T) => void,
      error?: (error: any) => void,
      complete?: () => void
    ): Subscription;
    getSnapshot: () => TEmitted | undefined;
  }

  For simpler actor-ref-like objects, the BaseActorRef<TEvent> interface has been introduced.

  interface BaseActorRef<TEvent extends EventObject> {
    send: (event: TEvent) => void;
  }

• 38e6a5e9 #2334 Thanks @davidkpiano! - When using a model type in createMachine<typeof someModel>(...), TypeScript will no longer compile machines that are missing the context property in the machine configuration:

  const machine = createMachine<typeof someModel>({
    // missing context - will give a TS error!
    // context: someModel.initialContext,
    initial: 'somewhere',
    states: {
      somewhere: {}
    }
  });

• 5f790ba5 #2320 Thanks @davidkpiano! - The typing for InvokeCallback have been improved for better event constraints when using the sendBack parameter of invoked callbacks:

  invoke: () => (sendBack, receive) => {
    // Will now be constrained to events that the parent machine can receive
    sendBack({ type: 'SOME_EVENT' });
  };

• 2de3ec3e #2272 Thanks @davidkpiano! - The state.meta value is now calculated directly from state.configuration. This is most useful when starting a service from a persisted state:

    const machine = createMachine({
      id: 'test',
      initial: 'first',
      states: {
        first: {
          meta: {
            name: 'first state'
          }
        },
        second: {
          meta: {
            name: 'second state'
          }
        }
      }
    });
  
    const service = interpret(machine);
  
    service.start('second'); // `meta` will be computed
  
    // the state will have
    // meta: {
    //   'test.second': {
    //     name: 'second state'
    //   }
    // }
  });