code: function resolveOptions (accumulator, resolveReducer) {
    const url = resolveUrl(accumulator)
    const specOptions = accumulator.reducer.spec.options
    return resolveReducer(accumulator, specOptions).then(acc => {
      const options = getRequestOptions(url, acc.value)
      return utils.assign(accumulator, { options })
    })
  }
docs: Resolve options object
  @param {Accumulator} accumulator
  @param {Function} resolveReducer
  @return {Promise<Accumulator>}