beforeEach([, fn][, options])

• fn <Function> | <AsyncFunction> 钩子函数。如果钩子使用回调，则回调函数作为第二个参数传入。默认值：空操作函数。

  ¥fn <Function> | <AsyncFunction> The hook function. If the hook uses callbacks, the callback function is passed as the second argument. Default: A no-op function.

• options <Object> 钩子的配置选项。支持以下属性：

  ¥options <Object> Configuration options for the hook. The following properties are supported:

  • signal <AbortSignal> 允许中止正在进行的钩子。

    ¥signal <AbortSignal> Allows aborting an in-progress hook.

  • timeout <number> 钩子会在几毫秒后失败。如果未指定，则子测试从其父测试继承此值。默认值：Infinity。

    ¥timeout <number> A number of milliseconds the hook will fail after. If unspecified, subtests inherit this value from their parent. Default: Infinity.

此函数用于创建一个在当前套件的每个子测试之前运行的钩子。

¥This function is used to create a hook running before each subtest of the current suite.

describe('tests', async () => {
  beforeEach(() => t.diagnostic('about to run a test'));
  it('is a subtest', () => {
    assert.ok('some relevant assertion here');
  });
}); 拷贝