Lab Instructions: Unit Testing

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Task 1: Add Jest as a devDependency

Open terminal. Make sure that it's pointing to jest-testing directory.
Install the jest npm package using the npm install command and the --save-dev flag.
Verify that the installation was completed successfully by opening the package.json file and confirming that the "devDependencies" entry lists jest similar to the following:

"devDependencies": {
    "jest": "^28.0.0"
}

Task 2: Update the test entry

In the package.json file, locate the "scripts" entry, and inside of it, update the test entry to jest.

Task 3: Code the timesTwo function

Open the timesTwo.js file and add a function named timesTwo. The function should take number as input and return the value 2 multiplied by the number. Export the timesTwo function as a module.

Task 4: Write the first test

Code a test call with the following arguments:

1. The description that reads: "returns the number times 2".
2. The second argument should expect the call to the timesTwo function, when passed the number 10, to be 20.
   
   

Task 5: Run the first test

With the terminal pointed at the jest-testing directory, run the test script using npm.