Popup tracking

[WIP] An implementation of the Popup API from vim in Neovim. Hope to upstream when complete

Goals

Provide an API that is compatible with the vim popup_* APIs. After stablization and any required features are merged into Neovim, we can upstream this and expose the API in vimL to create better compatibility.

Notices

• 2021-09-19: we now follow Vim’s convention of the first line/column of the screen being indexed 1, so that 0 can be used for centering.
• 2021-08-19: we now follow Vim’s default to noautocmd on popup creation. This can be overriden with vim_options.noautocmd=false

List of Neovim Features Required:

• Key handlers (used for popup_filter)
• scrollbar for floating windows
  • scrollbar
  • scrollbarhighlight
  • thumbhighlight

Optional:

• Add forced transparency to a floating window.
  • Apparently overrides text?
  • This is for the mask feature flag

Unlikely (due to technical difficulties):

• Add textprop wrappers?
  • textprop
  • textpropwin
  • textpropid
• “close”
  • But this is mostly because I don’t know how to use mouse APIs in nvim. If someone knows. please make an issue in the repo, and maybe we can get it sorted out.

Unlikely (due to not sure if people are using):

• tabpage

Progress

Suported Features:

• what
  • string
  • list of strings
• popup_create-arguments
  • border
  • borderchars
  • col
  • cursorline
  • highlight
  • line
  • {max,min}{height,width}
  • [?] moved
    • “any”
    • “word”
    • “WORD”
    • “expr”
    • (list options)
  • padding
  • [?] pos
    • Somewhat implemented. Doesn’t work with borders though.
  • posinvert
  • time
  • title
  • wrap
  • zindex

All known unimplemented vim features at the moment

• firstline
• hidden
• ~ pos
• fixed
• filter
• filtermode
• mapping
• callback
• mouse:
  • mousemoved
  • close
  • drag
  • resize
• (not implemented in vim yet) flip