freeCodeCamp/curriculum/challenges/espanol/06-quality-assurance/quality-assurance-and-testing-with-chai/test-if-an-object-is-an-instance-of-a-constructor.md

id	title	challengeType	forumTopicId	dashedName
587d824e367417b2b2512c57	Test if an Object is an Instance of a Constructor	2	301605	test-if-an-object-is-an-instance-of-a-constructor

--description--

As a reminder, this project is being built upon the following starter project on Repl.it, or cloned from GitHub.

#instanceOf asserts that an object is an instance of a constructor.

--instructions--

Within tests/1_unit-tests.js under the test labelled #18 in the Objects suite, change each assert to either assert.instanceOf or assert.notInstanceOf to make the test pass (should evaluate to true). Do not alter the arguments passed to the asserts.

--hints--

All tests should pass.

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

You should choose the correct method for the first assertion - instanceOf vs. notInstanceOf.

(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);
    }
  );

You should choose the correct method for the second assertion - instanceOf vs. notInstanceOf.

(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);
    }
  );

You should choose the correct method for the third assertion - instanceOf vs. notInstanceOf.

(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);
    }
  );

You should choose the correct method for the fourth assertion - instanceOf vs. notInstanceOf.

(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--

/**
  Backend challenges don't need solutions, 
  because they would need to be tested against a full working project. 
  Please check our contributing guidelines to learn more.
*/