Maybe throw NotSupportedError for createEvent('touchevent')

[zcorpan]

See w3c/touch-events#64

Depends on w3c/touch-events#111

Closes #952

• At least two implementers are interested (and none opposed):
  • Already implemented in Chromium, Gecko, WebKit.
• Tests are written and can be reviewed and commented upon at:
  • DOM: Test document.createEvent('touchevent') web-platform-tests/wpt#33605
  • DOM: Remove TouchEvent from someNonCreateableEvents web-platform-tests/wpt#33811
• Implementation bugs are filed:
  • Chrome: N/A
  • Firefox: N/A
  • Safari: N/A
  • Deno (only for aborting and events): ?
  • Node.js (only for aborting and events): ?

(See WHATWG Working Mode: Changes for more details.)

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[annevk]

Thanks for tackling this!

[zcorpan]

Via BrowserStack, I checked the tests in Safari 15.4 on an iPhone 13, Chrome and Firefox on Android 12 on a Google Pixel 6. There were no surprises other than a test bug which I've submitted a fix for at web-platform-tests/wpt#33811

I haven't checked Deno or Node, other than the results for the relevant tests are MISSING for Deno on wpt.fyi: https://wpt.fyi/results/dom/nodes/Document-createEvent.https.html?sha=937311ebfd&label=master&max-count=1&product=chrome&product=edge&product=firefox&product=safari&product=deno

[zcorpan]

When at least one of w3c/touch-events#115 and w3c/touch-events#114 are merged (and the term flows through to be visible to the bikeshed build server), the build error should go away.

[zcorpan]

CI is green now

[annevk]

Does this close #952? What about https://bugzilla.mozilla.org/show_bug.cgi?id=1693172?

[zcorpan]

Does this close #952?

Yes.

What about https://bugzilla.mozilla.org/show_bug.cgi?id=1693172?

Hmm. I thought Firefox exposed window.TouchEvent, since it passes the relevant test in https://wpt.fyi/results/touch-events/idlharness.window.html?label=experimental&label=master&aligned

But running the test locally on macOS desktop Firefox it's not exposed. Maybe it's a difference between Linux and macOS?

In any case, we should indeed make a decision whether window.TouchEvent should exist when "expose legacy touch event APIs" is false.

What's specified now in the touch events spec + this PR matches Chromium, but seemingly not Safari or Firefox.