[keycloak-dev] Htmlunit vs PhantomJS vs Chrome

[Stian Thorgersen]

We've picked Htmlunit as the default browser to run tests with due to it
being the fastest. Downside is that it simply doesn't work very well for
all tests, especially those heavy on the javascript side of things like
testing the JavaScript adapter and admin console.

Just saw that Chrome is actually bringing a headless option to Chrome 59
[1]. This is really nice as it allows headless testing with a real browser,
not just an emulated browser.

Ideally if this is fast we could use it as the default browser instead of
htmlunit. Obviously waiting until it's released on all platforms. If it's
not as fast as htmlunit then maybe there is a compromise.

The default browser would still be htmlunit. Then individual tests could be
marked (with an annotation on the class or on the WebDriver field). Those
marked would use Chrome in headless mode instead of htmlunit. Obviously
-Dbrowser would continue to override the browser in either case.

Thoughts? Anyone interested in giving the new headless Chrome option a spin
and evaluating how fast it is compared to htmlunit?

[1] https://developers.google.com/web/updates/2017/04/headless-chrome