@xstate/test - How to parametrize tests?

[a-y-u-s-h]

We can parametrize actions, activities, guards and services as a string while writing out the representation of state machine. I really like this pattern and in my all projects I keep the JSON/YAML representation separate from actions JS in their own YAML files. I would like to know if there's a way yet to allow us to parametrize test functions or whether that's on the todo list (not sure where that is).

Docs say that test key should be present in meta key, and if I describe my machine in YAML file, there's no way I can attach an async function for puppeteer in YAML file, so it needs to live somewhere else. For example, if this is the state machine (with tests):

const toggleMachine = Machine({
  id: 'toggle',
  initial: 'inactive',
  states: {
    inactive: {
      on: {
        /* ... */
      },
      meta: {
        test: async (page) => {
          await page.waitFor('input:checked');
        }
      }
    },
    active: {
      on: {
        /* ... */
      },
      meta: {
        test: async (page) => {
          await page.waitFor('input:not(:checked)');
        }
      }
    }
  }
});

It would be awesome to write it as (if not already supported):

id: toggle
initial: inactive
states:
  inactive:
    on:
      activate: active
    meta:
      test: test-inactive-state
  active:
    on:
      deactivate: inactive
    meta:
      test: test-active-state

Or maybe not inside meta but an optional tests key maybe:

id: toggle
initial: inactive
states:
  inactive:
    tests:
      - test-inactive-state
    on:
      activate: active
  active:
    tests:
      - test-active-state
    on:
      deactivate: inactive

And then add those test-inactive-state and test-active-state functions later inside an options object, when I pass it to interpret or maybe createModel. Is it not supported or not documented yet?

[davidkpiano]

I'll consider this for the next major version of @xstate/test - seems like a good idea.

[a-y-u-s-h]

Thanks!

[Andarist]

@a-y-u-s-h could u open a new issue about this? It would be easier to track this feature request if it would be an issue

[a-y-u-s-h]

Sure. Awesome!