Element.focusNextChild/focusPreviousChild do not respect hidden property

[KJ7LNW]

Summary

Element.prototype.focusNextChild and Element.prototype.focusPreviousChild do not check the hidden property before giving focus to children. This causes arrow key navigation to reach hidden elements in collapsible widgets like SelectList and SelectListMulti.

Expected Behavior

When a SelectList is collapsed, pressing UP/DOWN arrow keys should not navigate to the hidden menu items. Only the master button should be focusable when the dropdown is closed.

Actual Behavior

Arrow keys navigate through all children including those with hidden = true, causing focus to move to invisible elements.

Root Cause

Document.focusNext() and Document.focusPrevious() correctly check !currentElement.hidden before calling giveFocusTo_() (Document.js lines 243, 252, 267).

However, Element.focusNextChild() and Element.focusPreviousChild() (Element.js lines 543-569, 573+) call giveFocusTo_() unconditionally without checking the hidden property.

Suggested Fix

Add hidden check in Element.focusNextChild before giveFocusTo_:

// Current (Element.js ~line 562):
focusAware = this.document.giveFocusTo_( this.children[ index ] , type ) ;

// Suggested fix:
if ( ! this.children[ index ].hidden ) {
    focusAware = this.document.giveFocusTo_( this.children[ index ] , type ) ;
}

Same change needed in focusPreviousChild.

Environment

• terminal-kit version: 3.1.2
• Node.js version: 22.x
• Platform: Linux

Workaround

We are currently patching Element.prototype.focusNextChild and Element.prototype.focusPreviousChild at module load to add the hidden check, matching the behavior in Document.focusNext.

[cronvel]

Navigation should be mostly done using TAB and shift-TAB.
Can you provide a minimal sample code of an UI with the expected vs actual behavior?

I have very little time for this project, so a fix would happen only if it requires minimal work/attention (sorry, that's the most I can afford at the moment).

[KJ7LNW]

Can you provide a minimal sample code of an UI with the expected vs actual behavior?

I've monkey patched the fix for my own internal purposes. Basically, if you just create a pull down and populate it, then pressing up and down will s will select and cycle through things that are not visible instead of doing nothing or perhaps extending the existing menu. I don't have a trivial example at the moment, but if something comes along I will post it.

I have very little time for this project, so a fix would happen only if it requires minimal work/attention (sorry, that's the most I can afford at the moment).

That's okay. I don't mean to distract you from more important things. What I'm doing is experimentation and it's not production. I'm not in a hurry for anything.

Mostly I'm documenting issues as I find them so that if someone else has an issue they can find it, and maybe someone will propose a solution or provide a pull request.