Improve types for mocks and provide in config options

[cesalberca]

This PR allows users of TypeScript to use bracket notation without the need to cast to any.

Before:

;(config.mocks as any)['foo'] = {
  bar: 'baz'
}

After:

config.mocks['foo'] = {
  bar: 'baz'
}

Also, continuing work from this PR: #874, I set allowSyntheticDefaultImports to true in order to import default export without errors.

[eddyerburgh]

Is this PR complete?

[cesalberca]

Yes it is! However I'm still confused about the signaturee of methods: https://vue-test-utils.vuejs.org/api/#config. Is config.methods an object that receives a function that returns an object? Or an object that receives a function that declares some functions?

[eddyerburgh]

No, it's an object that's merged into component instance methods. The example is confusing, can you please replace it with this:

config.methods['getData'] = () => {}

[cesalberca]

If it's an object then the docs are not correct as:

config.methods['errors'] = () => {
  any: () => false
}

Is equivalent to:

config.methods['errors'] = function() {
 // This is a labeled statement inside the function, not an object
 any: () => false
}

If we wanted an object the docs should be as follows:

config.methods['errors'] = () => ({
  any: () => false
})

Note the parenthesis.

[eddyerburgh]

Yes that's why I asked if you could replace the example. As you said, it's incorrect.

[cesalberca]

Aaah, alright then! I'll change it then

[eddyerburgh]

Can you fix the linting error please?

https://circleci.com/gh/vuejs/vue-test-utils/7489?utm_campaign=vcs-integration-link&utm_medium=referral&utm_source=github-build-link

[cesalberca]

Done, ready to merge!

[eddyerburgh]

Great work, thanks :)