freeCodeCamp/curriculum/challenges/chinese/06-quality-assurance/quality-assurance-and-testi.../test-if-an-object-is-an-ins...

2.8 KiB

id title challengeType forumTopicId dashedName
587d824e367417b2b2512c57 测试对象是否是构造函数的实例 2 301605 test-if-an-object-is-an-instance-of-a-constructor

--description--

请注意,本项目在这个 Replit 项目的基础上进行开发。你也可以从 GitHub 上克隆。

#instanceOf 断言一个对象是一个构造器的实例。

--instructions--

tests/1_unit-tests.js 中,Objects 套件里标有 #18 的测试下,将每个 assert 改成 assert.instanceOfassert.notInstanceOf 方法,通过测试(结果应该返回 true)。 不要修改传给断言的参数。

--hints--

应通过所有测试。

(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=17').then(
    (data) => {
      assert.equal(data.state, 'passed');
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );

应该为第一个断言选择正确的方法:instanceOfnotInstanceOf

(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=17').then(
    (data) => {
      assert.equal(
        data.assertions[0].method,
        'notInstanceOf',
        'myCar is not an instance of Plane'
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );

应该为第二个断言选择正确的方法:instanceOfnotInstanceOf

(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=17').then(
    (data) => {
      assert.equal(
        data.assertions[1].method,
        'instanceOf',
        'airlinePlane is an instance of Plane'
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );

应该为第三个断言选择正确的方法:instanceOfnotInstanceOf

(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=17').then(
    (data) => {
      assert.equal(
        data.assertions[2].method,
        'instanceOf',
        'everything is an Object in JavaScript...'
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );

应该为第四个断言选择正确的方法:instanceOfnotInstanceOf

(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=17').then(
    (data) => {
      assert.equal(
        data.assertions[3].method,
        'notInstanceOf',
        'myCar.wheels is not an instance of String'
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );

--solutions--

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*/