Types for data: (context, event) => are 'any'

[lukehorvat]

Hi. I have the following foo state that invokes a child machine with context determined by an event:

foo: {
  invoke: {
    src: ChildMachine,
    data: (context, event) => ({
      mode: event.type === 'ONE' ? 1 : event.type === 'TWO' ? 2 : undefined,
    }),
    onDone: 'bar',
  },
},

The (context, event) => part gives a TS error:

Parameter 'context' implicitly has an 'any' type.
Parameter 'event' implicitly has an 'any' type.

Why doesn't it know the parameter types?

I fixed the error for now by being more explicit, but it doesn't feel nice:

foo: {
  invoke: {
    src: ChildMachine,
    data: (context: ParentContext, event: ParentEvents): Partial<ChildContext> => ({
      mode: event.type === 'ONE' ? 1 : event.type === 'TWO' ? 2 : undefined,
    }),
    onDone: 'bar',
  },
},

Side note: is it possible to define data the serialized way?

[Andarist]

Thank you for the report - I've started working on fixing this. The problem is that currently any is included in some union types and this always makes the whole union equal to any.

Side note: is it possible to define data the serialized way?

You could use services to do that though - you would just have to return ChildMachine.withContext(/* ... */) from a service creator based on received arguments (context and event).

[lukehorvat]

Just tried v4.11.0. Works great. Thanks!