coq.nvim 🐔

Named after the famous theorem prover

coq also means 鸡 in français québécois, and I guess 🥖.

Fast as FUCK and loads of features.

Faster Than Pure Lua

• Native C in-memory B-trees

• SQLite VM interrupts

• Coroutine based incremental & interruptible scheduler

• TCP-esque flow control

More details at the PERFORMANCE.md

Features

Note: Due to compression, reality is faster than gifs

Fast as fuck

• Results on every keystroke

• Throttling? Never heard of her

• Real time performance statistics

• Look at the gifs! The bottom few are the fastest when I didn’t slow down on purpose to show features.

Fuzzy Search

• Typo resistant

• Recency bonus

• Proximity bonus

• Weighted average of relative ranks & ensemble metrics

Error correction: cour -> colour_space, flgr -> flag_group, nasp -> Namespace

Preview

• Press key to view documentation in big buffer

• Auto open preview on side with most space

• Customizable location: n, s, w, e

• Ubiquitous: Tags, LSP, TreeSitter, Paths, Snippets

LSP

• Incremental completion

• Client-side caching

• Multi-server completion (i.e. tailwind + cssls)

• Multi-encoding utf-8, utf-16, utf-32

• Header imports

• Snippet Support

Install the Nvim Official LSP integration

Requires 2 lines of change to support LSP snippets

local lsp = require "lspconfig"
local coq = require "coq" -- add this

lsp.<server>.setup(<stuff...>)                              -- before
lsp.<server>.setup(coq.lsp_ensure_capabilities(<stuff...>)) -- after

Snippets

• Over 9000 built-in snippets

• 99% of LSP grammar, 95% of Vim grammar

• Press key to jump to next edit region.

• Linked regions

• Custom snippets with Live Repl

The % statistic comes from compiling the 10,000 snippets

TreeSitter

• Shows context

• Partial document parsing

• Auto-disable if document is too big

• Unicode ready

Treesitter is still unstable in nvim0.5: slow and crash prone

The promise is that Treesitter will have real time parsing on every keystroke, but it’s actually too slow on big files.

The Treesitter source only parses a limited number of lines about the cursor and only on Idle events due to unrealized performance promises.

CTags

• LSP like

• Incremental & automatic background compilation

• Non-blocking

Requires Universal CTags, NOT ctags

# MacOS
brew uninstall ctags           # bad
brew install   universal-ctags # good

# Ubuntu
apt remove  ctags              # bad
apt install universal-ctags    # good

Paths

• Preview contents

• $VARIABLE expansion, %EVEN_UNDER_WINDOWS%

• Relative to both cwd and file path

Buffers

• Real time completion

• Fast in files with thousands of lines

Registers

• words Last yank 0 + custom a-z coq_settings.clients.registers.words

• lines coq_settings.clients.registers.lines (a-z)

Tmux

Tabnine

• CPU preserving flow control

• Auto download & install & update

• Platform specific cgroupv2 & taskpolicy core pinning / CPU management.

T9 is disabled by default, I might remove it, if they do not improve the CPU usage. Their own bug tracker.

Enable via: coq_settings.clients.tabnine.enabled=true

Modular lua sources & external third party integrations

• Even faster than pure lua! (transparent sqlite caching)

• Tons of built-ins

• External third party plugins too

• Easy to hack

Shown above: shell repl.

Some other built-ins:

• nvim lua API

• vim runtime: ada, c, clojure, css, haskell, html, js, php, syntax

• scientific calculator

• comment banners

• moo!

• vimtex

• orgmode.nvim

• vim dadbod

• nvim-dap

Statistics

:COQstats

Validating config parser

• Prevents typos & type errors in your config

Here I make a type error on purpose inputting string instead of an integer.

Pretty

• Customizable

If you can’t see icons properly:

Either set let g:coq_settings = { 'display.icons.mode': 'none' } to disable icons, or install a supported font

Install

Windows requires symlinks support in git.

git config --global core.symlinks true

Needs python virtual env

apt install --yes -- python3-venv

Minimum version: python:3.8.2, nvim: 0.5, sqlite: recentish

Documentation

To start coq

" the [-s, --shut-up] flag will remove the greeting message
:COQnow [--shut-up]

🌟 If required, it will ask you to run :COQdeps, please run it and do :COQnow again.

There is built-in help command

:COQhelp [--web] [topic]

• :COQhelp config

• :COQhelp keybind

• :COQhelp snips

• :COQhelp fuzzy

• :COQhelp comp

• :COQhelp display

• :COQhelp sources

• :COQhelp misc

• :COQhelp perf

• :COQhelp stats

• :COQhelp custom_sources

FAQ

Default hotkeys?

Always:

When completion menu is open:

Unbound:

When hovering over a result, entering any key [a-z] will select it

This is a vim thing, I have zero control over :(

. Repeat

Set coq_settings.keymap.repeat to a hotkey.

See :COQhelp keybind for details

Flickering

By default, the old results are cleared on each keystroke, so the popup menu is closed right away.

You can disable this: at the cost of having stale results shown until the new ones come in.

let g:coq_settings = { 'display.pum.fast_close': v:false }

This is not the default because some LSP servers are very slow (ie. tailwindcss), leading to stale results being shown for too long.

Autostart COQ

let g:coq_settings = { 'auto_start': v:true } or let g:coq_settings = { 'auto_start': 'shut-up' }

This must be set BEFORE require("coq")

LSP too slow to show up on keystroke.

You have some options, each has its trade off:

1. Increase the coq_settings.limits.completion_auto_timeout.

This will slow down feedback on every keystroke, as coq waits for LSP.

2. Use the manual completion hotkey (default <c-space>)

Annoying! And the manual completion also has a timeout coq_settings.limits.completion_manual_timeout.

Some LSP servers will still fail to respond within the default .66 seconds, in that case pressing <c-space> multiple times might actually help some LSP servers catch up, depending on their implementation.

LSP sometimes not importing

Increase coq_settings.clients.lsp.resolve_timeout

This will however, make applying edits slower.

Missing Results

On keystroke only a max of coq_settings.match.max_results are shown.

Use manual completion hotkey to show all results.

Some LSP servers give inconsistent completions

This happens when certain LSP servers give you 1000s of unfiltered results in alphabetical order and you still have to respond in a few dozen milliseconds.

To eliminate a-z bias, coq does a random sort on the resultset and process and cache as many of them as possible within the performance window.

So if some results are not in the SQLite cache, and have yet to be processed, they will be missing. They might however still show up on later keystrokes.

Use the manual hotkey if you need to see everything.

My vim crashed!

Disable TreeSitter

Treesitter still needs stability work.

I want to use a different python version

vim.g.python3_host_prog=<absolute path to python>

If you like this…

Also check out

• sad, it’s a modern sed that does previews with syntax highlighting, and lets you pick and choose which chunks to edit.

• CHADTree, it’s a FULLY featured file manager.

• isomorphic-copy, it’s a cross platform clipboard that is daemonless, and does not require third party support.

Special Thanks & Acknowledgements

The snippets are compiled from the following open source projects:

• Shougo/neosnippet-snippets

• fatih/vim-go

• honza/vim-snippets

• Ikuyadeu/vscode-R

• Rocketseat/rocketseat-vscode-react-native-snippets

• dsznajder/vscode-es7-javascript-react-snippets

• johnpapa/vscode-angular-snippets

• sdras/vue-vscode-snippets

• snipsnapdev/snipsnap

• xabikos/vscode-javascript

• xabikos/vscode-react

• rafamadriz/friendly-snippets

Super special thanks goes to Typescript LSP.

Nothing like good motivation to improve my design than dumping 1000 results on my client every other keystroke.