@xstate/test Supporting functions when defining event cases

[dalwlad]

Description

In the current @xstate/test version (0.4.1), when defining the event test config, at the moment, cases can be an array of event data.

Feature request

It would be convenient to be able to access the testContext the same way it's possible today when defining the event exec function

Additional context

Ideally we would be able to do something like in the below code snippet

const testModel = createModel(machine).withEvents({
  eventName: {
    exec: [async] (testData, event) => {
      /* ... */
    },

    /* Current API */
    cases: [
      eventOne,
      eventTwo,
      ...
    ],
    
    /* Possible API 1 */
    cases: [async] (testData) => [
      {
        foo: testData.bar,
        baz: testData.baz
      },
    ],

    /* Possible API 2 */
    cases: [
      [async] (testData) => ({
        foo: testData.bar
      }),
      [async] (testData) => ({
        baz: testData.baz
      })
    ]
});

[SimeonC]

Found this in an issue marked as enhancement, as I found both that issue and this discussion at different times and they aren't linked thought I'd leave a comment. Looks like David prefers API 1 😆 #824

[dalwlad]

Thanks @SimeonC, seems to be the exact feature I'm looking for