run CopilotChatCommit when starting a commit message

[hellupline]

I tried to setup a autocmd for when I start a commit, Copilot chat would open automaticaly, but it keeps getting cwd error and returning bogus text

my attempt was:

vim.api.nvim_create_autocmd("BufEnter", {
  group = vim.api.nvim_create_augroup("gitcommit-copilotchat", { clear = true }),
  pattern = "COMMIT_EDITMSG",
  callback = function()
    local chat = require("CopilotChat")
    local prompt = chat.prompts().Commit
    chat.ask(prompt.prompt, { context = prompt.context })
  end,
})

the error message:

[CopilotChat] [ERROR 18:15:48] ~/.local/share/nvim/lazy/CopilotChat.nvim/lua/CopilotChat/init.lua:373: Failed to resolve context: git ...azy/CopilotChat.nvim/lua/CopilotChat/config/contexts.lua:172: attempt to call field 'cwd' (a nil value)

[4DRIAN0RTIZ]

In case it helps anyone, I made my own version. It generates the commit message based on the diffs of a file in staged. And then performs the commit. You can change de prompt language for you convenience

local chat = require("CopilotChat")
local select = require("CopilotChat.select")

local function extract_commit_message(response)
  local msg = response:match("```gitcommit(.-)```")
  if msg then
    return vim.trim(msg)
  else
    vim.notify("❌ No gitcommit code block found", vim.log.levels.ERROR)
    return nil
  end
end

local function commit_with_ai()
  local prompt = [[
    Write a commit message for the change following the commitizen convention.
    Keep the title under 50 characters and list each change on a separate line.
    Use the appropriate icon according to the type of change:
      ✨ feat, 🐛 fix, 📝 docs, 🎨 style, ♻️ refactor, 🚀 perf, ✅ test, 📦 build, 👷 ci, 🔥 chore, ⏪ revert.
    First, provide a summary of the change, then explain the details.
    Format it as a gitcommit code block.
    ]]

  chat.ask(prompt, {
    selection = select.buffer,
    context = { "git:staged" },
    callback = function(response)
      local msg = extract_commit_message(response)
      if not msg then return end

      vim.schedule(function()
        local buf = vim.api.nvim_create_buf(false, true)
        local lines = { "Commit with this message?", "" }
        local first = true
        for line in msg:gmatch("[^\r\n]+") do
          if first then
            table.insert(lines, line)
            table.insert(lines, "")
            first = false
          else
            table.insert(lines, line)
          end
        end
        vim.api.nvim_buf_set_lines(buf, 0, -1, false, lines)
        local width = math.max(60, math.min(100, vim.fn.strdisplaywidth(msg) + 4))
        local height = #lines + 4
        local win = vim.api.nvim_open_win(buf, true, {
          relative = "editor",
          width = width,
          height = height,
          row = math.floor((vim.o.lines - height) / 2),
          col = math.floor((vim.o.columns - width) / 2),
          style = "minimal",
          border = "rounded",
        })
        vim.api.nvim_buf_set_keymap(buf, "n", "y", "", {
          nowait = true,
          noremap = true,
          callback = function()
            vim.api.nvim_win_close(win, true)
            local result = vim.fn.system({ "git", "commit", "-m", msg })
            vim.notify("✅ Commit executed:\n" .. result)
          end,
        })
        vim.api.nvim_buf_set_keymap(buf, "n", "n", "", {
          nowait = true,
          noremap = true,
          callback = function()
            vim.api.nvim_win_close(win, true)
            vim.notify("❎ Commit canceled by user")
          end,
        })
        vim.api.nvim_buf_set_keymap(buf, "n", "<Esc>", "", {
          nowait = true,
          noremap = true,
          callback = function()
            vim.api.nvim_win_close(win, true)
            vim.notify("❎ Commit canceled by user")
          end,
        })
        vim.api.nvim_buf_set_option(buf, "modifiable", false)
        vim.api.nvim_buf_set_option(buf, "bufhidden", "wipe")
      end)
    end,
  })
end

vim.keymap.set("n", ";ccg", commit_with_ai, { desc = "AI Generate Commit" })

[burnskp]

I also spent some time setting this up. My method adds the generated commit message to the buffer where you can modify it afterwards. I added this to ~/.config/nvim/ftplugin/gitcommit.lua

vim.api.nvim_create_autocmd("BufEnter", {
  group = vim.api.nvim_create_augroup("gitcommit-copilotchat", { clear = true }),
  pattern = "COMMIT_EDITMSG",
  once = true,
  callback = function()
    local chat = require("CopilotChat")
    local buf = vim.api.nvim_get_current_buf()
    chat.ask(chat.prompts().Commit.prompt, {
      selection = require("CopilotChat.select").buffer,
      context = chat.prompts().Commit.context,
      model = "gpt-4.1",
      headless = true,
      callback = function(response)
        -- Extract content between first code block markers
        local commit_msg = response:match("```[%w]*\n(.-)\n?```")
        local lines
        if commit_msg then
          lines = vim.split(commit_msg, "\n", { plain = true })
        else
          lines = { "# Error: Unable to generate commit", "#" }
          for _, line in ipairs(vim.split(response, "\n", { plain = true })) do
            table.insert(lines, "# " .. line)
          end
        end
        vim.api.nvim_buf_set_lines(buf, 0, 0, false, lines)
        return response
      end,
    })
  end,
})