vue: Clarify what the return value of the callback param does in render

[lwkchan]

I'm currently learning vue-testing-library and had some trouble trying to set up vuex instance with simple-vuex. I found out elsewhere that a possible way to do this would be to use the callback parameter to return a store like the below

const store = createVuexStore(new RootStore())

// doesn't work because `createVuexStore(new RootStore())` is already an instance of `Vuex.Store`
render(MyComponent, {props: {happy: true}, store})

render(MyComponent, {props: {happy: true}}, () => ({ store }))

I think I could have noticed this sooner if the documentation described this line in the code: https://github.com/testing-library/vue-testing-library/blob/2312e180b12df3c599e8aa8a0ee85dcff7b108e7/src/vue-testing-library.js#L52. This is what i have tried to do in my proposed change above.

[afontcu]

Hi! Thank you for this!

I agree that docs should explain how to the returned value for the callback function works (btw, there's an example test in the repo using vue-i18n).

However, I feel the addition could be improved a bit. Do you think you could rephrase it to explain that the callback function merges its return value back to the options? I wouldn't link to vue test utils to avoid confusion, and maybe link to the example test I shared above? Would that have helped you?

[lwkchan]

thank you for your feedback @afontcu. I agree that mentioning the merge would make it clearer. I think the vue-i18n example was where I saw that the store could be added in the callback, so I have included that link as well as you suggested 😄

[afontcu]

Looks great 😃 thank you!