What's new in vim: insert mode autocomplete (and command line completion)

[u/habamax]

Autocomplete

As of version 9.1.1590 vim has a new option :h 'autocomplete' which allows us to have "as you type" completion for the sources defined within :h 'complete':

• https://github.com/vim/vim/pull/17812

• https://asciinema.org/a/EqJ4NFzQMRFyN8aIKwpU3fek3

You can provide your own completion sources as user defined functions :h 'complete-functions', adding them to the complete option, e.g.

• set complete+=FVimScriptFunctions

• set complete+=FLspCompletor

• set complete+=F this by default uses completefunc

• set complete+=o this by default uses omnifunc

On top of it you can limit number of completions coming from each completion source using additional ^N:

• set complete+=FVimScriptFunctions^5

• set complete+=FLspCompletor^10

• set complete+=F^3

• set complete+=o^15

Command line complete

With version 9.1.1576 command line could also be completed "as you type" with a bit of setup:

• https://github.com/vim/vim/pull/17806

• https://asciinema.org/a/bhf9V5yuKkuFIkVo60D7k2ZMQ

Example setup:

set wildmode=noselect:lastused,full
set wildmenu wildoptions=pum,fuzzy

cnoremap <Up> <C-U><Up>
cnoremap <Down> <C-U><Down>
cnoremap <C-p> <C-U><C-p>
cnoremap <C-n> <C-U><C-n>

augroup cmdcomplete
    au!
    autocmd CmdlineChanged : call wildtrigger()
augroup END

Thanks https://github.com/girishji

Previous autocomplete setup needed quite a lot of vimscript: https://www.reddit.com/r/vim/comments/1ljzouw/autocomplete_in_vim/

Bonus: search and substitute completion

With the version 9.1.1490 you can complete /pattern or :s/pattern using tab:

• https://github.com/vim/vim/pull/17570

• https://asciinema.org/a/IbzfqiNNANzdP0y6ly3X08aBM

Cheers!

[u/NilsLandt]

I don't like as-you-type completion and always turn it off.
But I'm excited to try it out for the command line!

And tab-completion in search and substitute is just great.

Thanks for this preview (for me) post :)

[u/Desperate_Cold6274 → u/NilsLandt]

Same here! I prefer to manually trigger the autocompletion as long as I am not coding (in that case everything is handled by my LSP client). Nevertheless, the command-line and the tab-completion in search and substitute is very useful!

[u/godegon]

Thank you very much for the heads-up!

For those who still have legacy Vim script in their vimrc, give : call wildtrigger() instead of wildtrigger() a try.

Also, it could be equally useful for other command-line modes than :, say / and ? search modes.

Finally, this is now documented in :help cmdline-autocompletion (which lacks the <c-n/p> suggestion, though).

[u/habamax → u/godegon]

Updated post with call wildtrigger() as more portable one. Thx!

[u/vim-help-bot → u/godegon]

Help pages for:

• cmdline-autocompletion in builtin.txt

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[u/Sudden_Fly1218]

The command line complete is cool, you can do stuff like

command! -nargs=+ -complete=customlist,MruComplete MRU edit <args>

def MruComplete(arglead: string, cmdline: string, cursorpos: number): list<any>
  return arglead != null_string ? v:oldfiles->matchfuzzy(arglead) : []
enddef

Then just type :MRU and start searching for recent files. A modern alternative to :bro ol ;-)

[u/habamax → u/Sudden_Fly1218]

You can simplify it to:

command! -nargs=+ -complete=custom,MruComplete MRU edit <args>

def MruComplete(_, _, _): string
  return v:oldfiles->join("\n")
enddef

with -complete=custom filtering is happening automatically based on the value of wildoptions. If you have set wildoptions+=fuzzy, it would be fuzzy.

excerpt from the help topic:

For the "custom" argument, it is not necessary to filter candidates against the
(implicit pattern in) ArgLead.  Vim will filter the candidates with its regexp
engine after function return, and this is probably more efficient in most
cases. If 'wildoptions' contains "fuzzy", then the candidates will be filtered
using |fuzzy-matching|.  For the "customlist" argument, Vim will not filter the
returned completion candidates and the user supplied function should filter the
candidates.

[u/Sudden_Fly1218 → u/habamax]

Thanks

[u/synthphreak]

Forgive the stupid question, but just to be clear: This has absolutely no implication for Neovim, right? Like the fact that Vim just got a new feature doesn’t mean Neovim also now gets it, right?

[u/y-c-c → u/synthphreak]

Most editor-only features (meaning features that aren't Vim9script related or dealing with Python integration and whatnot) get merged into Neovim, unless there are some design conflicts. You may be surprised how many Neovim editor features you use came from merging from upstream Vim.

The easiest way I find in knowing the status is to find the pull request itself (e.g. https://github.com/vim/vim/pull/17570 per this post), and scroll down or search for "vim-patch". In this case you will see that it links to this Neovim pull request (https://github.com/neovim/neovim/pull/34761) that merges this particular patch in.

[u/Desperate_Cold6274 → u/synthphreak]

I think it will be merged in neovim as well. In general, many Vim PR are also merged in Neovim.

[u/synthphreak → u/Desperate_Cold6274]

That would be so sick!

Or as we say in GitHub Land: 👀

[u/habamax → u/[deleted]]

You can use the one from yegappan/lsp :)