fix: support for DefineComponent shim

[pikax]

Support for the DefineComponent type

There's an issue with the passing the data function:

// TODO it should work
 mount(ShimedComponent, {
   data() {
     return {
       a: 1
     }
   }
})

[cexbrayat]

@pikax I gave it a try in one of my projects and it's a bit better indeed (no more issue on mount 👍).

But I still have issues with the type of vm.

For example, if your component looks like:

export default defineComponent({
  name: 'HelloWorld',
  props: {
    msg: String,
  },
  setup() {
    return { user: reactive({ name: 'Cédric' }) };
  }
});

then mounting this component in a test succeeds, but vm does not expose user:

describe('HelloWorld.vue', () => {
  it('renders props.msg when passed', () => {
    const msg = 'new message'
    const wrapper = shallowMount(HelloWorld, {
      props: { msg }
    })
    expect(wrapper.text()).toMatch(msg)
    expect(wrapper.vm.user.name).toBe('Cédric');
  })
})

This last line does not compile with Vue 3.0.1 and this patch of VTU:

tests/unit/example.spec.ts:11:28 - error TS2339: Property 'name' does not exist on type 'never'.
    11     expect(wrapper.vm.user.name).toBe('Cédric');

But it does compile with Vue v3.0.0. So maybe this is something to fix in vue-next... WDYT?

[pikax]

Can you provide a full example?

It works on my side

[lmiller1990]

Good to merge this? Seems this should go out asap - or do we want to wait on @cexbrayat to confirm his issue with data?

Thanks guys, you rock 👍

[cexbrayat]

@pikax this is exactly this use case, but using a SFC

See cexbrayat/vue-301-shims@819bab0
Even with your fix, there is still an issue with wrapper.vm