Primeagen's LSP config without lsp-zero

lsp.lua

vim.opt.signcolumn = 'yes'

vim.diagnostic.config({
	virtual_text = true,
})

vim.api.nvim_create_autocmd('LspAttach', {
	desc = 'LSP keybindings',
	callback = function(event)
		local opts = {buffer = event.buf}

		vim.keymap.set("n", "gd", function() vim.lsp.buf.definition() end, opts)
		vim.keymap.set("n", "K", function() vim.lsp.buf.hover() end, opts)
		vim.keymap.set("n", "<leader>vws", function() vim.lsp.buf.workspace_symbol() end, opts)
		vim.keymap.set("n", "<leader>vd", function() vim.diagnostic.open_float() end, opts)
		vim.keymap.set("n", "[d", function() vim.diagnostic.goto_next() end, opts)
		vim.keymap.set("n", "]d", function() vim.diagnostic.goto_prev() end, opts)
		vim.keymap.set("n", "<leader>vca", function() vim.lsp.buf.code_action() end, opts)
		vim.keymap.set("n", "<leader>vrr", function() vim.lsp.buf.references() end, opts)
		vim.keymap.set("n", "<leader>vrn", function() vim.lsp.buf.rename() end, opts)
		vim.keymap.set("i", "<C-h>", function() vim.lsp.buf.signature_help() end, opts)
	end
})

local lspconfig = require('lspconfig')
local lsp_defaults = lspconfig.util.default_config

lsp_defaults.capabilities = vim.tbl_deep_extend(
	'force',
	lsp_defaults.capabilities,
	require('cmp_nvim_lsp').default_capabilities()
)

require('mason').setup()
require('mason-lspconfig').setup({
	ensure_installed = {
		'tsserver',
		'lua_ls',
		'rust_analyzer',
	},
	handlers = {
		function(server)
			lspconfig[server].setup({})
		end,
		lua_ls = function()
			lspconfig.lua_ls.setup({
				settings = {
					Lua = {
						runtime = {
							version = 'LuaJIT',
						},
						diagnostics = {
							globals = {'vim'}
						},
						workspace = {
							library = {
								vim.env.VIMRUNTIME,
							}
						}
					}
				}
			})
		end
	}
})

vim.opt.completeopt = {'menu', 'menuone', 'noselect'}

local cmp = require('cmp')

cmp.setup({
	snippet = {
		expand = function(args)
			require('luasnip').lsp_expand(args.body)
		end,
	},
	sources = {
		{name = 'nvim_lsp'},
		{name = 'buffer'},
	},
	mapping = cmp.mapping.preset.insert({
		['<C-Space>'] = cmp.mapping.complete(),
		['<C-b>'] = cmp.mapping.scroll_docs(-4),
		['<C-f>'] = cmp.mapping.scroll_docs(4),
	}),
	window = {
		documentation = cmp.config.window.bordered(),
	}
})