freeCodeCamp/curriculum/challenges/english/06-quality-assurance/quality-assurance-and-testing-with-chai/learn-how-javascript-assertions-work.md

id	title	challengeType	forumTopicId	dashedName
587d824a367417b2b2512c46	Learn How JavaScript Assertions Work	2	301589	learn-how-javascript-assertions-work

--description--

Working on these challenges will involve you writing your code using one of the following methods:

• Clone this GitHub repo and complete these challenges locally.
• Use our Replit starter project to complete these challenges.
• Use a site builder of your choice to complete the project. Be sure to incorporate all the files from our GitHub repo.

When you are done, make sure a working demo of your project is hosted somewhere public. Then submit the URL to it in the Solution Link field.

--instructions--

Within tests/1_unit-tests.js under the test labelled #1 in the Basic Assertions suite, change each assert to either assert.isNull or assert.isNotNull 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=0').then(
    (data) => {
      assert.equal(data.state, 'passed');
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );

You should choose the correct method for the first assertion - isNull vs. isNotNull.

(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=0').then(
    (data) => {
      assert.equal(data.assertions[0].method, 'isNull', 'Null is null');
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );

You should choose the correct method for the second assertion - isNull vs. isNotNull.

(getUserInput) =>
  $.get(getUserInput('url') + '/_api/get-tests?type=unit&n=0').then(
    (data) => {
      assert.equal(data.assertions[1].method, 'isNotNull', '1 is not null');
    },
    (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.
*/