There are two ways to test web applications:
The mocha-loader executes your code with the mocha framework. If you run the code it’ll show the results in the web page.
Tip: when using
! in the bash command line, you must escape it by prepending a
webpack 'mocha!./test.js' testBundle.js # index.html is a HTML page which loads testBundle.js open index.html
The webpack-dev-server will automatically create a HTML page which loads the script. It also re-executes the tests when files have changed.
webpack-dev-server 'mocha!./test.js' --hot --inline --output-filename test.js open http://localhost:8080/test
--hot and it’ll only execute tests which have changed or have changed dependencies.
You can use webpack with karma. Add
"webpack" as preprocessor to your karma config.
If you write your web app only in CommonJs and don’t use loaders or other webpack-specific features, you can test it in node.js. Just use a node.js testing framework, i. e. mocha.
If you use webpack-specific features it may not be possible to run the code with node.js. webpack allows to configure a target system: i. e. you can compile code so that it can run in node.js (configuration option
target: "node"). Then use a node.js testing framework to run the bundle.
webpack test.js /tmp/testBundle.js --target node mocha /tmp/testBundle.js
Hint: You can use the
null-loaderfor stylesheets instead of the
style-loaderdoesn’t work in node.js as it requires a DOM.
To make debugging tests easier, you can add source map support using node-source-map-support:
webpack test.js /tmp/testBundle.js --target node mocha --require source-map-support/register /tmp/testBundle.js
Make sure to configure the
devtool option to output the source map.