.config/nvim/after/plugin/lsp.lua

local lsp = require('lsp-zero')

lsp.preset('recommended')

lsp.ensure_installed({
  'rust_analyzer',
})

-- Fix Undefined global 'vim'
lsp.configure('lua-language-server', {
    settings = {
        Lua = {
            diagnostics = {
                globals = { 'vim' }
            }
        }
    }
})


local cmp = require('cmp')
local cmp_select = {behavior = cmp.SelectBehavior.Select}
local cmp_mappings = lsp.defaults.cmp_mappings({
  ['<C-p>'] = cmp.mapping.select_prev_item(cmp_select),
  ['<C-n>'] = cmp.mapping.select_next_item(cmp_select),
  ['<C-y>'] = cmp.mapping.confirm({ select = true }),
  ['<C-Space>'] = cmp.mapping.complete(),
})

cmp_mappings['<Tab>'] = nil
cmp_mappings['<S-Tab>'] = nil

lsp.setup_nvim_cmp({
  mapping = cmp_mappings
})

lsp.set_preferences({
    suggest_lsp_servers = false,
    sign_icons = {
        error = 'E',
        warn = 'W',
        hint = 'H',
        info = 'I'
    }
})

lsp.on_attach(function(client, bufnr)
  local opts = {buffer = bufnr, remap = false}

  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>fr', function() vim.lsp.buf.references() end, opts)
  vim.keymap.set('n', '<leader>rn', function() vim.lsp.buf.rename() 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', '<leader>vca', function() vim.lsp.buf.code_action() 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('i', '<C-h>', function() vim.lsp.buf.signature_help() end, opts)
end)

lsp.setup()

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