Aider Plugin for Neovim

This is a simple plugin for Neovim that allows you to open a terminal window inside Neovim and run Aider. I wrote it as an experiment in using Aider which is by far the best AI coding assistant I've seen, and now just a few keystrokes away in vim.

Installation

You can install the Aider Plugin for Neovim using various package managers. Here are the instructions for some common ones:

Using packer.nvim

use 'joshuavial/aider.nvim'

Using vim-plug

Plug 'joshuavial/aider.nvim'

Using dein

call dein#add('joshuavial/aider.nvim')

Using lazy.nvim

{
  "joshuavial/aider.nvim",
  config = function()
    require("aider").setup({
      -- your configuration comes here
      -- if you don't want to use the default settings
      auto_manage_context = true,
      default_bindings = true,
      debug = false, -- Set to true to enable debug logging
    })
  end,
}

Usage

The Aider Plugin for Neovim provides several functions and commands:

1. AiderOpen: Opens a terminal window with the Aider command.

   • Arguments:
     • args: Command line arguments to pass to aider (default: "")
     • window_type: Window style to use ('vsplit' (default), 'hsplit', or 'editor')
   • Note: If an Aider job is already running, calling AiderOpen will reattach to it, even with different flags.

2. AiderBackground: Runs the Aider command in the background.

   • Arguments:
     • args: Command line arguments to pass to aider (default: "")
     • message: Message to pass to the Aider command (default: "Complete as many todo items as you can and remove the comment for any item you complete.")

3. AiderAddModifiedFiles: Adds all git-modified files to the Aider chat.

   • This function can be called directly or through the user command :AiderAddModifiedFiles

When Aider opens (through either function), it automatically adds all open buffers to both commands. It's recommended to actively manage open buffers with commands like :ls and :bd.

Examples of using these commands:

:AiderOpen
:AiderOpen -3 hsplit
:AiderOpen "AIDER_NO_AUTO_COMMITS=1 aider -3" editor
:AiderBackground
:AiderBackground -3
:AiderBackground "AIDER_NO_AUTO_COMMITS=1 aider -3"
:AiderAddModifiedFiles

You can set custom keybindings for these commands in your Neovim configuration. For example:

vim.api.nvim_set_keymap('n', '<leader>ao', ':AiderOpen<CR>', {noremap = true, silent = true})
vim.api.nvim_set_keymap('n', '<leader>ab', ':AiderBackground<CR>', {noremap = true, silent = true})
vim.api.nvim_set_keymap('n', '<leader>am', ':AiderAddModifiedFiles<CR>', {noremap = true, silent = true})

Run aider --help to see all the options you can pass to the CLI.

The plugin provides the following default keybindings:

• <leader>Ao: Open a terminal window with the Aider defaults (gpt-4).
• <leader>AO: Open a terminal window with the Aider command using the gpt-3.5-turbo-16k model for chat.
• <leader>Ab: Run the Aider command in the background with the defaults.
• <leader>AB: Run the Aider command in the background using the gpt-3.5-turbo-16k model for chat.
• <leader>Am: Add all git-modified files to the Aider chat.

These keybindings are set up using which-key, providing a descriptive popup menu when you press <leader>A.

Setup

The Aider Plugin for Neovim provides a setup function that you can use to configure the plugin. This function accepts a table with the following keys:

• auto_manage_context: A boolean value that determines whether the plugin should automatically manage the context. If set to true, the plugin will automatically add and remove buffers from the context as they are opened and closed. Defaults to true.
• default_bindings: A boolean value that determines whether the plugin should use the default keybindings. If set to true, the plugin will require the keybindings file and set the default keybindings. Defaults to true.
• debug: A boolean value that determines whether the plugin should enable debug logging. When set to true, it will print debug information to help troubleshoot issues. Defaults to false.

Here is an example of how to use the setup function:

require('aider').setup({
  auto_manage_context = false,
  default_bindings = false,
  debug = true,
  vim = true, -- Pass the `--vim` flag to Aider when opening a new chat

  -- only necessary if you want to change the default keybindings. <Leader>C is not a particularly good choice. It's just shown as an example.
  vim.api.nvim_set_keymap('n', '<leader>C', ':AiderOpen<CR>', {noremap = true, silent = true})
})

In this example, the setup function is called with a table that sets auto_manage_context to false and default_bindings to false. This means that the plugin will not automatically manage the context and will not use the default keybindings.

aider_background_status

The plugin exposes a global variable called aider_background_status that you can use to check the status of the Aider background process. Here is a snippet which will create a A that will change colours based on whether the background process is running or not.

lualine_x = {{
    function()
      return 'A'
    end,
    color = { fg = '#8FBCBB' }, -- green
    cond = function()
      return _G.aider_background_status == 'idle'
    end
  },
  {
    function()
      return 'A'
    end,
    color = { fg = '#BF616A' }, -- red
    cond = function()
      return _G.aider_background_status == 'working'
    end
  }
}

Reloading buffers after Aider updates the underlying code

Run the :e command to re-edit the current buffer updating its contents with any changes made since initially loading it.

Tips for Working with Buffers in Vim

If you're not familiar with buffers in Vim, here are some tips:

• Use :ls or :buffers to see all open buffers.
• Use :b <number> or :buffer <number> to switch to a specific buffer. Replace <number> with the buffer number.
• Use :bd or :bdelete to close the current buffer.
• Use :bd <number> or :bdelete <number> to close a specific buffer. Replace <number> with the buffer number.
• Use :bufdo bd to close all buffers.

NOTE

if you resize a split the nvim buffer can truncate the text output, chatGPT tells me there isn't an easy work around for this. Feel free to make a PR if you think it's easy to solve without rearchitecting and using tmux or something similar.