nixos-configs/home-manager/neovim/lspconfig.lua

require("lsp-format").setup({})

local on_attach = function(client, bufnr)
	local bufmap = function(keys, func)
		vim.keymap.set("n", keys, func, { buffer = bufnr })
	end

	bufmap("<leader>r", vim.lsp.buf.rename)
	bufmap("<leader>a", vim.lsp.buf.code_action)

	bufmap("gd", vim.lsp.buf.definition)
	bufmap("gD", vim.lsp.buf.declaration)
	bufmap("gI", vim.lsp.buf.implementation)
	bufmap("<leader>D", vim.lsp.buf.type_definition)

	bufmap("gr", require("telescope.builtin").lsp_references)
	bufmap("<leader>s", require("telescope.builtin").lsp_document_symbols)
	bufmap("<leader>S", require("telescope.builtin").lsp_dynamic_workspace_symbols)

	bufmap("K", vim.lsp.buf.hover)

	vim.api.nvim_buf_create_user_command(bufnr, "Format", function(_)
		vim.lsp.buf.format()
	end, {})
end

local capabilities = vim.lsp.protocol.make_client_capabilities()
capabilities = require("cmp_nvim_lsp").default_capabilities(capabilities)

require("neodev").setup()
require("lspconfig").nil_ls.setup({
	on_attach = on_attach,
	capabilities = capabilities,
})
require("lspconfig").pyright.setup({
	on_attach = on_attach,
	capabilities = capabilities,
})
require("lspconfig").gopls.setup({
	on_attach = on_attach,
	capabilities = capabilities,
})
require("lspconfig").terraformls.setup({
	on_attach = on_attach,
	capabilities = capabilities,
})

local function has_treefmt()
    local git_root = vim.fn.systemlist("git rev-parse --show-toplevel")[1]
    if vim.v.shell_error ~= 0 then
        return false
    end
    local treefmt_path = git_root .. "/treefmt.nix"
    return vim.fn.filereadable(treefmt_path) == 1
end

vim.api.nvim_create_autocmd("BufWritePost", {
    pattern = "*",
    callback = function()
	if vim.fn.expand("%:p") ~= vim.fn.getcwd() .. "/.git/COMMIT_EDITMSG" and has_treefmt() then
		vim.cmd("silent !treefmt > /dev/null 2>&1")
        end
    end,
    group = vim.api.nvim_create_augroup("TreefmtAutoformat", { clear = true }),
})