neovim/lua/lsp/cmp.lua

-- import nvim-cmp plugin safely
local cmp_status, cmp = pcall(require, "cmp")
if not cmp_status then
  return
end

-- import luasnip plugin safely
local luasnip_status, luasnip = pcall(require, "luasnip")
if not luasnip_status then
  vim.notify("没有找到luasnip")
  return
end

-- import lspkind plugin safely
local lspkind_status, lspkind = pcall(require, "lspkind")
if not lspkind_status then
  vim.notify("没有找到lspkind")
  return
end

-- load vs-code like snippets from plugins (e.g. friendly-snippets)
-- require("luasnip/loaders/from_vscode").lazy_load()

vim.opt.completeopt = "menu,menuone,noselect"

cmp.setup({
  snippet = {
    expand = function(args)
      luasnip.lsp_expand(args.body)
    end,
  },
  mapping = cmp.mapping.preset.insert({
    ["<S-Tab>"] = cmp.mapping.select_prev_item(), -- previous suggestion
    ["<Tab>"] = cmp.mapping.select_next_item(), -- next suggestion
    ["<C-b>"] = cmp.mapping.scroll_docs(-4),
    ["<C-f>"] = cmp.mapping.scroll_docs(4),
    ["<C-Space>"] = cmp.mapping.complete(), -- show completion suggestions
    ["<C-e>"] = cmp.mapping.abort(), -- close completion window
    ["<CR>"] = cmp.mapping.confirm({ select = false }),
  }),
  -- sources for autocompletion
  sources = cmp.config.sources({
    { name = "nvim_lsp" }, -- lsp
    { name = "luasnip" }, -- snippets
    { name = "buffer" }, -- text within current buffer
    { name = "path" }, -- file system paths
  }),
  -- configure lspkind for vs-code like icons
  formatting = {
    format = lspkind.cmp_format({
      maxwidth = 50,
      ellipsis_char = "...",
    }),
  },
})

-- / 查找模式使用 buffer 源
cmp.setup.cmdline("/", {
  mapping = cmp.mapping.preset.cmdline(),
  sources = {
    { name = "buffer" },
  },
})

-- : 命令行模式中使用 path 和 cmdline 源.
cmp.setup.cmdline(":", {
  mapping = cmp.mapping.preset.cmdline(),
  sources = cmp.config.sources({
    { name = "path" },
  }, {
    { name = "cmdline" },
  }),
})