The tests present here are used to test the generated HTML from rustdoc. The goal is to prevent unsound/unexpected GUI changes. This is using the [browser-ui-test] framework to do so. It works as follows: It wraps [puppeteer] to send commands to a web browser in order to navigate and test what's being currently displayed in the web page. You can find more information and its documentation in its [repository][browser-ui-test]. If you need to have more information on the tests run, you can use `--test-args`: ```bash $ ./x.py test src/test/rustdoc-gui --stage 1 --test-args --debug ``` If you don't want to run in headless mode (helpful to debug sometimes), you can use `--no-headless`: ```bash $ ./x.py test src/test/rustdoc-gui --stage 1 --test-args --no-headless ``` To see the supported options, use `--help`. Important to be noted: if the chromium instance crashes when you run it, you might need to use `--no-sandbox` to make it work: ```bash $ ./x.py test src/test/rustdoc-gui --stage 1 --test-args --no-sandbox ``` [browser-ui-test]: https://github.com/GuillaumeGomez/browser-UI-test/ [puppeteer]: https://pptr.dev/