Method add

packages/next/src/server/lib/async-callback-set.ts:4–6

(callback: () => Promise<void>)

  private callbacks: (() => Promise<void>)[] = []

  public add(callback: () => Promise<void>) {
    this.callbacks.push(callback)
  }

  public async runAll(): Promise<void> {
    if (!this.callbacks.length) {