async vim+neovim

[prabirshrestha]

Given that both neovim and vim now supports jobs and channels are there any plans to add async sources?

Shougo is also rewriting unite https://github.com/Shougo/denite.nvim

[mattn]

Possible but not stable

[prabirshrestha]

@mattn wanted to know if there has been any update to this.

I'm trying to implement a proof of concept async FindAllReferences for https://github.com/prabirshrestha/vim-ts so would like to have something like function! ctrlp#ts#findAllReferences()#asyncinit or some api so i can call ctrlp#add(....)

[prabirshrestha]

I prototyped this with vim-lsp and quickpick and created a plugin called quickpick-lsp.vim. I used an example of LspWorkspaceSymbols since a project could contain hundreds and thousands of results and need to cancel previous requests and request a new one.

Here is an api I came up for ctrlp. The core of this is to support a new property called events that would allow us to hookup to different events such as user changing the search text and then give us apis to set the items/append items/clearitems/set busy indicators. Debounce is also pretty common so would be good to have a first class debounce support. The api is completly backwards compatible which means existing sources don't need to be migrated.

call add(g:ctrlp_ext_vars, {
    \ 'init': 'ctrlp#lsp#init()',
    \ 'events': 'ctrlp#lsp#events',
        \ 'debounce': 250,
    \ 'accept': 'ctrlp#async#accept',
    \ 'lname': 'LspWorkspaceSymbols',
    \ 'sname': 'LSPWorkSym',
    \ 'type': 'tabs',
    \ })

function! ctrlp#lsp#events(type, ctx) abort
    if a:type == 'change'
        call s:cancel(a:ctx)
        call s:search(a:ctx)
    elseif a:type == 'init'
        call s:search(a:ctx)
    elseif a:type == 'close'
        call s:cancel(a:ctx)
    endif
endfunction

function! s:cancel(ctx) abort
    if has_key(a:ctx.data, 'timer')
        call timer_stop(a:ctx.data.timer)
        call remove(a:ctx.data, 'timer')
    endif
endfunction

function! s:search(ctx) abort
    call a:ctx.set_busy(1)
    let a:ctx.data = { 'counter': 0, 'items': [], 'total': 5 }
    let a:ctx.data.timer = timer_start(500, function('s:add_items', [a:ctx]), { 'repeat': a:ctx.data.total })
endfunction

function s:callback(ctx) abort
    let a:ctx.data.counter += 1
    call add(a:ctx.items, a:ctx.data.counter)
    call a:ctx.set_items(a:items)
    if a:ctx.data.total == a:ctx.data.counter
        call a:ctx.data.set_busy(0)
    endif
endfunction

Here is another example where it could be really useful such as searching and installing NPM packages.

What are your thoughts on introducing this new api?

[prabirshrestha]

Actually even got a simpler api working which is very similar to existing ctrlp apis. https://github.com/prabirshrestha/ctrlp.vim/tree/events

It introduces several new apis.

• [x] ctrlp#input to get the current search term
• [x] change event to listen to the change in search term
• [x] ctrlp#set(lines) to set the lines. to clear use ctrl#set([])
• [x] ctrlp#get() to get the lines
• [x] ctrlp#update() to force re-render once you set.
• [ ] implement user_data for set so in accepts can get the value and do something with it.
• [ ] implement busy indicator. using ctrlp#busy(1)

cal add(g:ctrlp_ext_vars, {
    \ 'init': 'ctrlp#month#init()',
    \ 'change': 'ctrlp#month#change()',
    \ 'accept': 'ctrlp#month#accept',
    \ 'lname': 'month',
    \ 'sname': 'month',
    \ 'type': 'tabe',
    \ })

let s:months= ["January","February","March","April","May","June","July","August","September","October","November","December"]
fu! ctrlp#month#change()
    let l:input = ctrlp#input()
    call ctrlp#set(filter(copy(s:months), 'v:val =~ l:input'))
    call ctrlp#update()
endf

Will try implementing vim-lsp SearchWorkspaceSymbols on this now.

[prabirshrestha]

Sent a PR at https://github.com/ctrlpvim/ctrlp.vim/pull/543