01 - Set up test framework.md

Practical 1 - Set up a test framework

Objectives

• Create a test project/framework for an existing app
• Install a test runner
• Set the test runner to run when npm test is called
• Install an assertion library
• Run the "test suite" with a green result

Extensions

None

Set-up steps

1. Pre-req: Visual Studio Code is installed
2. Pre-req: Git is installed
3. Clone the Demo repository:
   • git clone https://github.com/mjhilton/testing-workshop-demos
4. Check out the Start Point for Prac 1:
   • git checkout Prac01-StartPoint
   • This references a defined tag in the repository, you must use exactly this name
5. Create a branch to make your changes on without impacting the main repo:
   • git checkout -b Prac01
   • This branch is your own working space, you can call it anything you want

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Practical steps

1. Install Mocha and add it as a dev dependency for our project
2. Install Chai and add it as a dev dependency for our project
3. Update your package.json so that mocha is executed when npm test is called
4. Create an empty test file under the test folder
5. Run npm test and ensure the result is green/no errors: "0 passing"

Solutions

Here's a step-by-step walkthrough of the practical steps, for if you get stuck :)

1. Install Mocha and add it as a dev dependency for our project
   • npm install --save-dev Mocha
2. Install Chai and add it as a dev dependency for our project
   • npm install --save-dev chai
3. Update your package.json so that mocha is executed when npm test is called
   • Open package.json
   • Find the scripts array
   • Ensure it contains a test script, which executes mocha, like this:

     "scripts": {
         "test": "mocha"
     }

4. Create an empty test file under the test folder
   • Call it name-to-number-service-tests.js
5. Run npm test and ensure the result is green/no errors: "0 passing"