update testing doc 3.0 with a11y paragraph

[lemoustachiste]

Adding a paragraph about how to set up accessibility testing in a test suite. I did lose way too much of my time trying to get a11ySuite to work only to discover that this is not the right way any more.

[ghost]

Thanks! I will take a look as soon as possible

[ghost]

Thanks again @lemoustachiste and sorry for the delay.

There's nothing in the web-component-tester changelog about a11y-suite no longer working, so I'm curious as to whether something needs to be fixed rather than changing the docs to outline a new process.

What makes you say that a11y-suite is no longer the right way to do it - were you given this info by someone on the Polymer team or did you see a commit somewhere that removed support for it?

Can you point me in the right direction by linking a team member/commit/etc so I can check in with the team? :) Thank you in advance

Ping @aomarks

[aomarks]

I'm not really familiar with axe/pwa-helpers, @notwaldorf does this look reasonable?

[lemoustachiste]

@katejeffreys, no worries.

I am a newcomer to Polymer and I initially tried to implement everything following the docs, only to hit walls (and I tried many ways to go about them).

I had a11ySuite implemented as documented, but that was definitely not working (and I did spend a solid amount of time there). I posted on stackoverflow, as well as on the slack channel, and this is what I got: https://stackoverflow.com/questions/50517884/polymer-3-0-a11ysuite-testing-error.

Resorting to the approach described in the PR worked, and seeing that pwa-starter-kit (which seems to be a more solid reference than the docs) used that too, I thought this was the new way.

[ghost]

@lemoustachiste thanks for the clarification!

@usergenic, @rictic, the most recent entry about a11y in the web-components-tester changelog mentions that users should import a11ySuite from wct-browser-legacy. The web-component-tester README still says it uses a11ySuite.

From looking at the pre-monorepo history of the web-component-tester changelog, it looks like Fred had something to do with this so I'm not sure who to ask.

Can either of you confirm

1. Should importing a11ySuite from wct-browser-legacy still work for users of web-component-tester?
2. Should the testing docs recommend and describe how to use axe-core for accessibility testing?