In this exercise you will be separating a test into setup, exercise, and verify phases. This distinct and well-defined separation of steps makes your test more reliable, maintainable, and expressive.

The phases are defined as follows:

  • Setup - create objects, variables, and set conditions that your test depends on

  • Exercise - execute the functionality you are testing

  • Verify - check your expectations against the result of the exercise phase. You can use the assert library here

Clear separation of each phase makes a test easier to read, change, and validate.



The same test is written twice – once in a naive approach, once using setup, exercise, and verify phases.

Run the test suite.


Both tests have errors! The test output will tell you which line threw an error for each test.

Following the examples below, fix both tests using the correct call to .pop().

const arr = ['entry1', 'entry2']; ['entry1', 'entry2'].pop(); // for naive test arr.pop(); // for 3phase test

Which test approach was easier to read and edit? Answer this for yourself then move on to the next exercise.

Sign up to start coding

Mini Info Outline Icon
By signing up for Codecademy, you agree to Codecademy's Terms of Service & Privacy Policy.
Already have an account?