Measuring the coverage of your code

Code coverage is one of the most used and understandable metrics to evaluate the quality of a piece of software. If a test exercises a particular portion of code, the code is said to be covered. This suggests that that particular portion of code is working correctly and has less chance of containing bugs.

Getting ready

Before measuring your code coverage, ensure that you complete the Adding some Karma to your workflow recipe as we will be using Karma to help us.

How to do it...

Create a new directory and place a file named package.json in it. Inside it, write the following:

{
 "name": "learning-code-coverage",
 "version": "1.0.0"
}

This creates an npm project. In the same directory, run the following command to install our dependencies:

npm install vue karma karma jasmine karma-jasmine karma-coverage karma-chrome-launcher --save-dev

The package.json file changes accordingly.

The karma-coverage plugin uses the underlying software, Istanbul, to measure and display...