command-palette launch is very slow in v1.25.0-beta

[t9md]

Description

Launching by command-palette:toggle is very slow in Atom-v1.25.0-beta.
Why? render-on-visible #101 feature not working correctly because incorrect {visible} options is passed to elementForItem.

What is happening now on command-palette:toggle is "render initial 10 items" then "immediately render all items" because of incorrect visible state determination in atom-select-list

I created PR atom/atom-select-list#25 to fix this.
No change required on command-palette side.

Steps to Reproduce

launch command-palette:toggle

Expected behavior: [What you expect to happen]

Actual behavior: [What actually happens]

Reproduces how often: [What percentage of the time does it reproduce?]

Versions

Atom v1.24.0 have no issue
Atom v1.25.0 and later have issue

[t9md]

If atom/atom-select-list#25 get merged and using that version of select-list will fix this issue.
No change required on command-palette's code.

[t9md]

You can notice big DEALY between timing from mini-editor-open to mini-editor-focus(by blue-border).

• Before fix: big GAP between mini-editor-open to blue-border-focus-indicator. Typing text is not immediately inputed to mini-editor
• After fix: no GAP, immediate focused-blue-border on open mini-editor. Can start typing immediately

Before fix (current atom-beta v1.25.0-beta2)

After fix (using atom/atom-select-list#25):

Detail of what's happenning

Command rendered in 2 steps.
step 1 render 10 command, then show mini-editor(its' OK).
step 2 render rest of all items(over 700 if installed vim-mode-plus), which make command-palette's UX really slow.

Step 2 rendering is just unnecessary rendering since its invisible item. But because of BUG it's happening.

It spend long time for visibilityObserver.change related function call.
Which actually rendering all command(over 700 command in my case since I'm vim-mode-plus user).
This is just bug, fixed it in atom/atom-select-list#25.

[daviwil]

Fixed by atom/atom-select-list#25