Bug: Keydown events supply incorrect values for event.code

[spthiel]

Describe the bug
When using element.trigger('keydown.xyz'), some keys incorrectly pass the keyCode as code to handlers of KeyboardEvents.

This fundamentally breaks testing for keyboard navigation when f.ex. a dropdown has to be tested for keydown.home, keydown.end, space and enter where a handler with check for event.code is the best practice

To Reproduce
https://stackblitz.com/edit/github-bbenms?file=src%2FButton.vue&view=editor

->
Event.code logs a string representation of Event.keyCode for various keys.
Tested keys that do not work correctly: Home, End, Enter, Space, Escape

Expected behavior
Event.code should correctly log the name of the key

Related information:

  System:
    OS: Linux 5.15 Linux Mint 21.3 (Virginia)
    CPU: (20) x64 12th Gen Intel(R) Core(TM) i7-12700H
    Memory: 14.30 GB / 31.02 GB
    Container: Yes
    Shell: 0.96.0 - /home/n/.cargo/bin/nu
  npmPackages:
    @vue/test-utils: ^2.4.5 => 2.4.6 
    vitest: ^1.5.0 => 1.6.0 
    vue: ^3.5.12 => 3.5.12 

Additional context

[cexbrayat]

Yes, I think this behavior is there for backward compatibility (see

test-utils/src/createDomEvent.ts

Lines 102 to 117 in 3988a31

	// get the keyCode for backwards compat
	const keyCode =
	keyCodesByKeyName[keyModifiers[0]] ||
	(options && (options.keyCode || options.code))
	const eventProperties = {
	...systemModifiersMeta, // shiftKey, metaKey etc
	...options, // What the user passed in as the second argument to #trigger
	bubbles: meta.bubbles,
	cancelable: meta.cancelable,
	// Any derived options should go here
	keyCode,
	code: options.code || keyCode,
	// if we have a `key`, use it, otherwise dont set anything (allows user to pass custom key)
	...(keyModifiers[0] ? { key: keyModifiers[0] } : {})
	}

)

Feel free to open a PR if you think that could be omproved without breaking existing applciations 👍

[spthiel]

for backward compatibility

What kind of backwards compatability are we talking here? To my knowledge Event.code has never used to house the keyCode.
This seems to me to just break web standard

[cexbrayat]

keyCode was a thing but is deprecated https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode

But as I said, we're welcoming any contribution to improve this use case

[spthiel]

keyCode was a thing but is deprecated

Yes I understand keyCode was deprecated but "code" wasn't and was never used to save a number.
I can contribute here but my idea would be to just remove the "backwards compatibility"

[spthiel]

(see)

Actually looking at your code snippet it seems this issue would already be partially solved if a new version was built due to #2434 which would at least allow the 2nd test case in the repro to succeed