feat(types): RouterConfig for multiple components (#3217)

[javiertury]

Closes #3217

The test demonstrates that with correct typings, typescript is able to infer that route is of type Route on its own.

             abc: route => route.params,

[posva]

Thanks for this!

[javiertury]

Done

[posva]

Thanks a lot. Let me just move the children next to components as well and I will merge this

[andersbc]

The associated commit broke my ts use case

I have a custom interface for my Router configuration, e.g.:

// file: routes.ts
// ...
import { RouteConfig } from 'vue-router'

interface MyRouteConfig extends RouteConfig {
  meta?: MyMeta; // <- defined elsewhere
}

export const routes: Array<MyRouteConfig> = [
  // ... the usual route configuration, with my added meta-thing
]

After the commit, the RouteConfig is now a union type, i.e.. RouteConfig = RouteConfigSingleView | RouteConfigMultipleViews

However, typescript can't extend from union types, because "An interface can only extend an object type or intersection of object types with statically known members"

What I really need is to extends the new RouteConfigMultipleViews type, but it doesn't get exported. Any chance of exporting it? Thanks :-)

[javiertury]

That was a case I missed.

They are trying to fix it in #3234. Personally I think that using a generic RouteConfig<Meta = any> as proposed in this comment is a good solution.

[posva]

FYI, adding a generic to the type should go through an RFC because is not that simple of a change