JavaScript Code Coverage Tools for Web Application Developers

To measure code coverage, we should use tools that can measure the depth of testing done by the testing types during the test execution phase. To do so, we use tools that instrument the website source code by adding different counters and analyzers that in return report back the percentage of lines of code covered by testing and the percentage of statements and branches. With that, we can assess the overall coverage and quality of our product.

For the JavaScript development language, the most used tool is Istanbul, which also uses the Babel plugin. Most leading test automation frameworks have a plugin for Istanbul, making it the most recommended tool for measuring code coverage.