feat(keyboard): keep key pressed for multiple keydown events

[patricklizon]

What:

Trigger multiple keydown events in a single key press

Why:

As requested in #618

How:

I followed @ph-fritsche suggestions #618 (comment)

• added repeatModifier detection at getNextKeyDef
• added repeatKey to keyboardState

Checklist:

• Documentation
• Tests
• Ready to be merged
  

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[ph-fritsche]

First of all thanks a lot for taking the time to contribute. ❤️

The implementation does not properly solve the issue yet.

When a key is pressed in the browser, the browser dispatches a keydown event every n ms.
(Usually there is a primary delay before the key is considered "pressed" and then there is a secondary delay between each of the keydown events until the key is released or another one is either pressed or released - both usually according to some system setting.)

For each of the keydown events there might be the default behavior of a keypress and depending on the active element an input event.

Instead of dispatching each event multiple times the whole implementation needs to loop for fireKeyDownTimes.

[patricklizon]

@ph-fritsche Thank you for explaining how triggering keyboard events work in browser. That's great something I was not aware of. It's great learning opportunity for me, I'll definitely dig deeper into the topic and the source code of library 🙂

[ph-fritsche]

I started with a review but achieving this while keeping the code readable required quite some refactoring so I opened a PR.

[ph-fritsche]

I just noticed that we might leak state into another call if the last key def has a repeat modifier and keyboardState is reused on another call.

[codecov]

Codecov Report

Merging #728 (2a46dc2) into main (fcbdf21) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##              main      #728   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           51        51           
  Lines          994      1005   +11     
  Branches       413       408    -5     
=========================================
+ Hits           994      1005   +11     

Impacted Files	Coverage Δ
src/keyboard/getNextKeyDef.ts	100.00% <100.00%> (ø)
src/keyboard/keyboardImplementation.ts	100.00% <100.00%> (ø)

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[ph-fritsche]

Looks good to me now.

[ph-fritsche]

@patricklizon Could you file a PR for the docs?
https://github.com/testing-library/testing-library-docs/blob/main/docs/ecosystem-user-event.mdx

[ph-fritsche]

@all-contributors add @patricklizon code

[allcontributors]

@ph-fritsche

I've put up a pull request to add @patricklizon! 🎉

[github-actions]

🎉 This PR is included in version 13.5.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

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