Insufficient error information

[tomsseisums]

I am setting up Vue environment with webpack, flow and eslint and testing out how it works.

Apparently, it didn't take much time to hit an interesting case.

---

Code:

// @flow
type DataFactory = () => { msg: string, bingo?: number }

type ModuleType = {
  +name: string,
  data: DataFactory
}

export default ({
  name: 'HelloWorld',
  data () {
    return {
      msg: 'Welcome to Your Vue.js App',
      bingo: 'string'
    }
  }
} : ModuleType)

Interactive version @ flow.org

---

The type DataFactory requires that if bingo is provided, it should be a number. As can be seen in the export, it's a string.

On flow.org, that results in quite an expressive error:

9: export default ({                   
                   ^ object literal. This type is incompatible with
17: } : ModuleType)
        ^ object type
   Property `data` is incompatible:
      11:   data () {
                 ^ function. This type is incompatible with
      6:   data: DataFactory           
                 ^ function type
         This parameter is incompatible:
            12:     return {               
                           ^ object literal. This type is incompatible with
            2: type DataFactory = () => { msg: string, bingo?: number }                            
                                        ^ object type
               Property `bingo` is incompatible:
                  14:       bingo: 'string'                 
                                   ^ string. This type is incompatible with
                  2: type DataFactory = () => { msg: string, bingo?: number }
                                                                     ^ number

Where as with eslint, I get:

> yarn lint --no-color --format codeframe
yarn run v1.3.2
$ eslint --ext .js,.vue src --no-color --format codeframe
error: object literal:  This type is incompatible with 'object type'. See line 17 (flowtype-errors/show-errors) at src\components\HelloWorld.vue:33:17:
  31 | }
  32 |
> 33 | export default ({
     |                 ^
  34 |   name: 'HelloWorld',
  35 |   data () {
  36 |     return {


1 error found.
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

Which appears to be the first message reported (matches the one on flow.org), though, the least descriptive one.

Is it a configuration error or a bug or missing feature or...?

[jdmota]

Flow's output changed since this issue was reported. Do you still think that we should output more information? Or can this be closed? Thanks

[tomsseisums]

I haven't expanded upon this ever since.