第 46 课：顺序重复关闭的幂等契约

import { describe, expect, it } from "@ohos/hypium";
class FakeHandle {
  releaseCount: number = 0;
  async release(): Promise<void> {
    this.releaseCount += 1;
    await Promise.resolve();
  }
}
class Channel {
  private closed: boolean = false;
  private handle: FakeHandle;
  constructor(handle: FakeHandle) { this.handle = handle; }
  async close(): Promise<void> {
    if (this.closed) { return; }
    await this.handle.release();
    this.closed = true;
  }
}
export default function sequentialCloseTest(): void {
  describe("sequential close", () => {
    it("repeatedCloseReleasesOnce", 0, async () => {
      const handle: FakeHandle = new FakeHandle();
      const channel: Channel = new Channel(handle);
      await channel.close();
      await channel.close();
      expect(handle.releaseCount).assertEqual(1);
    });
  });
}