Add support for setting DOM focus via the wiki testable statements

[joanmarie]

We have several tests (e.g. aria-activedescendant) which require setting DOM focus on an element. And I can add this manually to an already generated test as a step, e.g.:

      {
         "type" : "event",
         "element" : "test",
         "event" : "focus",
         "title": "Put focus on test element"
      },

Is this the desired way to do DOM focus? If not, what is? But if so.... Looking at make_tests.pl:

      } elsif ($type eq "event") {
        print STDERR "Event support from wikis is not yet implemnted at line #lineCounter\n";

Since we are currently doing wiki-based testable statements, it would be great to solve this problem so the aria-activedescendant tests don't have to be run manually.

[joanmarie]

Updated link for make_tests.pl: https://github.com/w3c/web-platform-tests/blob/master/wai-aria/tools/make_tests.pl#L282

[joanmarie]

Syntax in spec for event: https://spec-ops.github.io/atta-api/index.html#event

[joanmarie]

Tests in the wiki using the syntax (sans description, but...), start here: https://www.w3.org/wiki/ARIA_1.1_Testable_Statements#application_activedescendant

[joanmarie]

Sample output when using make_tests.pl to generate tests from wiki:

Event support from wikis is not yet implemnted at line #lineCounter
Event support from wikis is not yet implemnted at line #lineCounter
Event support from wikis is not yet implemnted at line #lineCounter
Event support from wikis is not yet implemnted at line #lineCounter

[halindrome]

We need a wiki syntax for the event... which I thought we had specified.

[joanmarie]

Isn't the syntax we specified what I commented above?

[halindrome]

No. That's the JSON structure.

[halindrome]

Question: do you think that the JSON you are putting in the activedescendant tests actually works? ATTAcomm has support for it - it calls focus. But my understanding was that focus was not portable and didn't necessarily emulate a user setting focus reliably.

[joanmarie]

It doesn't cause an accessible focus event to be emitted, but if I remove that step from the json, I get new failures, namely that the element lacks STATE_FOCUSED.