Function getUnexpectedStateShapeWarningMessage

src/combineReducers.ts:14–60

(
  inputState: object,
  reducers: { [key: string]: Reducer<any, any, any> },
  action: Action,
  unexpectedKeyCache: { [key: string]: true }
)

import { kindOf } from class="st">'./utils/kindOf'

function getUnexpectedStateShapeWarningMessage(
  inputState: object,
  reducers: { [key: string]: Reducer<any, any, any> },
  action: Action,
  unexpectedKeyCache: { [key: string]: true }
) {
  const reducerKeys = Object.keys(reducers)
  const argumentName =
    action && action.type === ActionTypes.INIT
      ? class="st">'preloadedState argument passed to createStore'
      : class="st">'previous state received by the reducer'

  if (reducerKeys.length === 0) {
    return (
      class="st">'Store does not have a valid reducer. Make sure the argument passed ' +
      class="st">'to combineReducers is an object whose values are reducers.'
    )
  }

  if (!isPlainObject(inputState)) {
    return (
      `The ${argumentName} has unexpected type of "${kindOf(
        inputState
      )}". Expected argument to be an object with the following ` +
      `keys: class="st">"${reducerKeys.join('", class="st">"')}"`
    )
  }

  const unexpectedKeys = Object.keys(inputState).filter(
    key => !reducers.hasOwnProperty(key) && !unexpectedKeyCache[key]
  )

  unexpectedKeys.forEach(key => {
    unexpectedKeyCache[key] = true
  })

  if (action && action.type === ActionTypes.REPLACE) return

  if (unexpectedKeys.length > 0) {
    return (
      `Unexpected ${unexpectedKeys.length > 1 ? class="st">'keys' : class="st">'key'} ` +
      `class="st">"${unexpectedKeys.join('", class="st">"')}" found in ${argumentName}. ` +
      `Expected to find one of the known reducer keys instead: ` +
      `class="st">"${reducerKeys.join('", class="st">"')}". Unexpected keys will be ignored.`
    )
  }
}

function assertReducerShape(reducers: {
  [key: string]: Reducer<any, any, any>