Neovim, clangd and Treesitter on Windows

About

In this tutorial I will show you how to setup Neovim on Windows. This is a minimal setup that will allow you to work with C/C++ codebases. You can always customize your setup further if you wish.

The majority of Neovim setups are typically done on Linux or MacOS. Windows isn't too different but there are some gotchas if you're are using the MSVC (cl.exe) instead of clang or g++ like on Linux.

Scoop Package Manger

The first thing you will need to install is Scoop. Scoop is a package manager for Windows, and we will use it to install Neovim and all the dependencies of the various plugins. To install, follow the the instructions from Scoop's homepage.

After installing scoop use it to install the Windows Terminal. The Windows Terminal will give you a better experience than using the default command line. You can easily install patched fonts to view icons in Neovim.

scoop install windows-terminal

With Scoop installed, we will now install neovim and all dependencies for the various packages that will also be installed for neovim. See below for the command and a description of the package and which plugin requires it.

scoop install neovim clangd llvm fd ripgrep

clangd — Used by the LSP server for intellisense
llvm — Required by the Treesitter plugin to compile language parsers
fd — Required by Telescope plugin to search for files on filesystem
ripgrep — Required by Telescope plugin as a faster alternative for grep

Neovim Setup

Plugin Manager

On Windows your init.lua file will be stored at ~/AppData/Local/nvim/init.lua. Open up this file and install the following plugins for Neovim. I am using Packer, but you can use the plugin manager of your choosing.

require('packer').startup(function()
	use 'wbthomason/packer.nvim'
	use 'neovim/nvim-lspconfig'
	use { 'nvim-treesitter/nvim-treesitter', run = ':TSUpdate' }

	-- Use the latest recommended tag for telescope
	use { 'nvim-telescope/telescope.nvim', tag = '0.1.4', requires = 'nvim-lua/plenary.nvim' }
end)

LSP and clangd

Add the following to your init.lua to setup LSP and use clangd.

local lspconfig = require 'lspconfig'
lspconfig.clangd.setup {
    cmd = {'clangd.exe'}, -- Add more strings to the dictionary for addition command line args
}

Take a look at the lspconfig README on how to set keymaps to allow you to goto defenition, etc.

Treesitter

We installed the llvm package with scoop so that that Treesitter will be able to compile the language parsers.

require'nvim-treesitter.configs'.setup {
	ensure_installed = 'all',	-- Add only the ones you want if you don't want all languages.
	highlight = { enable = true }
}

Telescope

Telescope is a great plugin to perform global search, find files and list references to a variable. You can also bind these action to shortcut keys. Take a look at the Telescope README.

require 'telescope'.setup {}

Install Plugins

With init.lua now setup, close and reopen Neovim to reload this file. You will get errors about missing packages. Use :PackerSync to download all the packages, then close and reopen neovim. There should be no errors this time.

compile_commands.json

Now we get to the Windows specific stuff. clangd.exe looks for a compile_commands.json file in the root directory of your project. You can have it look for the file in a different directory by passing in the --compile-commands-dir command line argument to clangd.exe. This file contains all the commands used to build every source file in your project. For information on how to obtain this file, look at the clangd Getting Started page. If using g++ or clang to compile there is probably nothing you have to do in this file. But, if you are using cl.exe you will have to perform one extra step.

Replace all instances of C:/path/to/cl.exe with clang-cl.exe in your compile_commands.json. This binary was installed when we installed llvm. All it does is translate the MSVC command switches (such as /I) to clang/g++ compatiable ones (-I in this example). This allows clangd to work on Windows.

If you are still running into some issues with missing headers, check out the clangd guide on System Headers