Flow 0.57.3 shows no errors

[on3iro]

I tried flow 0.57.3 inside various projects where I used 0.56.0 before.
I made a few errors on purpose, which the old version showed correctly.
On 0.57.3 however flow says No Errors.

Am I doing something wrong or does the current version not work?

On a side-note:
Following the offical documentation I am using
a disjoint Union for redux actions. I was expecting flow to throw an error if I do not provide
cases for every action in my reducer, but flow somehow seems to be fine with that.

// types
const INIT = 'INIT'
const USER_FETCH_SUCCESS = 'USER_FETCH_SUCCESS'
const USER_FETCH_FAIL = 'USER_FETCH_FAIL'

type User = {
  +id: string,
  +name: string,
  +age: number
}

type Init = {| type: typeof INIT |}
type UserFetchSuccess = {| type: typeof USER_FETCH_SUCCESS, payload: User |}
type UserFetchFail = {| type: typeof USER_FETCH_FAIL, payload: Object |}

type Action = Init | UserFetchSuccess | UserFetchFail

// Reducer
const fakeUserReducer = (state: State = {
  loading: false,
  user: null,
  error: null
}, action: Action): State => {
  switch (action.type) {
    case INIT:
      return loop(
        {...state, loading: true},
        Cmd.run(fetchUser, {
          successActionCreator: userFetchSuccessfulAction,
          failActionCreator: userFetchFailedAction,
          args: ['userA']
        })
      )

    case USER_FETCH_SUCCESS:
      return { ...state, user: action.payload, loading: false }

     // Flow wont throw an error, even if this case is missing
    // case USER_FETCH_FAIL:
      // return { ...state, error: action.payload, loading: false }

    default:
      return state
  }
}

[apsavin]

Maybe related to facebook/flow#5105

[apsavin]

@on3iro see facebook/flow#5180

[mroch]

seems to be a flow issue, not a flow-bin issue.