freeCodeCamp Challenge Guide: Learn How JavaScript Assertions Work

Learn How JavaScript Assertions Work

Problem Explanation

To begin, locate the file “tests/1_unit_tests.js”.

This file contains multiple suites of tests for the project, and this first challenge requires you to make the tests in /** 1 */ to pass.


Hint 1

The two lines in the test should be changed from to either assert.isNull() or assert.isNotNull().


Solution 1 (Click to Show/Hide)
/** 1 - Use assert.isNull() or assert.isNotNull() to make the tests pass. **/
test('#isNull, #isNotNull', function() {
    'this is an optional error description - e.g. null is null'
  assert.isNotNull(1, '1 is not null');
1 Like