Break a promise

broken.js

const broken = (promise, state = {
  pending:  true,
  settled:  false,
  
  resolved: false,
  rejected: false,
  
  value: undefined,
  error: undefined,
}) => (
  promise.then(
    x => {
      state.resolved = true
      state.value    = x
    },
    x => {
      state.rejected = true
      state.error    = x
    }
  ),
  
  promise.finally(() => {
    state.pending = false 
    state.settled = true
  }),
  
  Object.keys(state)
    .map(flag => ({
      [flag]: () => state[flag]
    })
    .reduce(Object.assign, {})
)