Replace event.keyCode with event.key

[joedolson]

Much of the scripting across non-React JS WordPress codebase uses event.keyCode to manage keyboard events. keyCode has been deprecated for many years, and we really only need to maintain backwards compatibility with this as long as we supported Internet Explorer, since IE11 continued to have buggy support for event.key.

event.code still has unreliable support, which makes this harder to implement, but event.key is widely supported.

In many cases, using event.key is more predictable, as is is less dependent on physical keyboard layout.

[rishabhwp]

I’d like to work on this issue and submit a PR updating the codebase to use event.key instead of event.keyCode.

[jonsurrell]

​There's an entire @wordpress/keycodes package that relies on keyCode. I wonder how best to handle that. Much of the package defines constants to deal with keyCode. Do you have thoughts on what should be done with that package?

[joedolson]

@jonsurrell I'd say that having a package that depends on a deprecated property continuing to be supported is a bit risky. But it does have the advantage that it's already abstracted, so if it needs to be updated at some point, that should be pretty manageable.

I'm more concerned about the core scripting, because it's not abstracted, so if any browser actually removed keyCode, it would be a pretty big project to resolve it. I think that the abstractions in @wordpress/keycodes make that a much easier task.

I don't honestly think there's a lot of risk here - there's just too much dependence on keyCode across the web for it to be removed, but we can reduce the surface of the problem pretty easily.

Trac ticket: https://core.trac.wordpress.org/ticket/63759

This PR replaces the deprecated keyCode property with key in key event handlers within the media folder.

Trac ticket: https://core.trac.wordpress.org/ticket/63759

This PR replaces the deprecated keyCode property with key in key event handlers within the admin and lib folder.

Trac ticket: https://core.trac.wordpress.org/ticket/63759

This PR replaces the deprecated keyCode property with key in key event handlers within the theme folder.

Trac ticket: https://core.trac.wordpress.org/ticket/63759

This PR replaces the deprecated keyCode property with key in key event handlers within the wp folder.

There are multiple files that require replacing event.keyCode with event.key. I realized that combining all changes into a single PR would result in too many file modifications, making it difficult to review and test effectively.
To keep things manageable, I’ve decided to create separate PRs for each set of changes.

I’m closing this PR for now. Please let me know if you have any concerns or suggestions.

I think that makes sense. The logical thing is probably to transform the ticket into a task and add smaller tickets to progress towards completion.