DEFAULT_HANDLER returns undefined

[imdkva]

Value of data of a new state is undefined when machine.next(STATE) called without payload arguments. Reason is DEFAULT_HANDLER receives undefined as last arg

[antongolub]

Can not reproduce. Could you add a bit more details?

• cyclone version
• machine config

Any transition handler gets previously stored data as the first arg. If optional payload is empty, args length is still equal 1, and DEFAULT_HANDLER works like identity — returns the prev value.

Have a look:

export const DEFAULT_HANDLER: IHandler = (...args) => args.pop()

public next (state: IState, ...payload: Array<IAny>): IMachine {
    if (this.key) {
      throw new MachineError(LOCK_VIOLATION)
    }

    const handler = Machine.getHandler(state, this.history, this.transitions)
    const current = this.current()
    const data = handler(current.data, ...payload)
    const id = generateId()
    const date = generateDate()

    this.history.push({
      state,
      data,
      id,
      date
    })

    if (this.history.length > Machine.getHistoryLimit(this.opts.historySize)) {
      log.debug('history limit reached')
      this.history.shift()
    }

    return this
  }