dotfiles/nvim/lua/config/plugins/nvim-cmp.lua

-- Reference: https://github.com/hrsh7th/nvim-cmp#recommended-configuration
return function()
  local cmp = require "cmp"

  cmp.setup {
    snippet = {
      expand = function(args)
        vim.snippet.expand(args.body)
      end,
    },
    window = {
      completion = cmp.config.window.bordered(),
      documentation = cmp.config.window.bordered(),
    },
    mapping = cmp.mapping.preset.insert {
     ['<Tab>'] = cmp.mapping(function(fallback)
        if cmp.visible() then
          cmp.select_next_item()
        elseif vim.snippet.jumpable(1) then
          vim.snippet.jump(1)
        else
          fallback()
        end
      end, { 'i', 's' }),
      -- And something similar for vim.snippet.jump(-1)
      ['<C-b>']  = cmp.mapping.scroll_docs(-4),
      ['<C-f>']  = cmp.mapping.scroll_docs(4),
      ['<C-CR>'] = cmp.mapping.complete(),
      ['<C-e>']  = cmp.mapping.abort(),
      ['<CR>']   = cmp.mapping.confirm({ select = true }), -- Accept currently selected item. Set `select` to `false` to only confirm explicitly selected items.
    },
    sources = cmp.config.sources({{ name = 'nvim_lsp' }}, {{ name = 'buffer' }})
  }

  -- Use buffer source for `/` and `?` (if you enabled `native_menu`, this won't work anymore).
  cmp.setup.cmdline({ '/', '?' }, {
    mapping = cmp.mapping.preset.cmdline(),
    sources = {
      { name = 'buffer' }
    }
  })

  -- Use cmdline & path source for ':' (if you enabled `native_menu`, this won't work anymore).
  cmp.setup.cmdline(':', {
    mapping = cmp.mapping.preset.cmdline(),
    sources = cmp.config.sources({
      { name = 'path' }
    }, {
      { name = 'cmdline' }
    })
  })
end