[Enter] keyPress on HTMLAnchorElement

[ph-fritsche]

• @testing-library/user-event version: 13
• Chrome 89.0.4389.90

When investigating #554 I stumbled over a strange behavior:
The browser (Chrome) does not fire a keypress event for [Enter] on an HTMLAnchorElement.
It does fire the keypress event (but no click) if the keydown occured on another element and the keydown event handler moved the focus to the HTMLAnchorElement.

Reproduction repository:

Using this to play around with events: https://codesandbox.io/s/keyevent-vtdcc?file=/src/App.js

Suggested solution:

This needs more investigation on how exactly browsers handle keyPress for [Enter]

[ph-fritsche]

There are also keypress events with repeat: true.
Also the click event triggered per Enter has pointerId: -1

[ph-fritsche]

The behavior for Enter on <a href="something"/> is inconsistent across browsers.

In Chrome:
On a keydown with repeat=false, the browser dispatches a click event. The following keypress is omitted.
If the keydown occurred on another element, the behavior of that element is applied and the keypress is dispatched as usual.

In Firefox:
On a keypress, the browser dispatches a click event.

I couldn't find any specification on this, it seems to be up to the browser vendor how to handle interaction with hyperlinks.
So for the moment I think we'll stick to the easier implementation.