Function createNotifyManager

packages/query-core/src/notifyManager.ts:17–96

()

export const defaultScheduler: ScheduleFunction = systemSetTimeoutZero

export function createNotifyManager() {
  let queue: Array<NotifyCallback> = []
  let transactions = 0
  let notifyFn: NotifyFunction = (callback) => {
    callback()
  }
  let batchNotifyFn: BatchNotifyFunction = (callback: () => void) => {
    callback()
  }
  let scheduleFn = defaultScheduler

  const schedule = (callback: NotifyCallback): void => {
    if (transactions) {
      queue.push(callback)
    } else {
      scheduleFn(() => {
        notifyFn(callback)
      })
    }
  }
  const flush = (): void => {
    const originalQueue = queue
    queue = []
    if (originalQueue.length) {
      scheduleFn(() => {
        batchNotifyFn(() => {
          originalQueue.forEach((callback) => {
            notifyFn(callback)
          })
        })
      })
    }
  }

  return {
    batch: <T>(callback: () => T): T => {
      let result
      transactions++
      try {
        result = callback()
      } finally {
        transactions--
        if (!transactions) {
          flush()
        }
      }
      return result
    },
    /**
     * All calls to the wrapped function will be batched.
     */
    batchCalls: <T extends Array<unknown>>(
      callback: BatchCallsCallback<T>,
    ): BatchCallsCallback<T> => {
      return (...args) => {
        schedule(() => {
          callback(...args)
        })