Please help to get git diff into prompt :)

[dvogt23]

Hey thanks for this great plugin, I would try to have something like this as a prompt for my commit messages, but have no idea how to get my local git diff into this prompt. Any suggestions? :)

[David-Kunz]

Hi @dvogt23 ,

Thanks! You can also modify the prompt templates programmatically and I would do it like that:

Create a lua function to

1. get the output of git diff
2. Put that into an appropriate prompt
3. Put that prompt into a temporary require('gen').prompts['someTmp']
4. Invoke it with :Gen someTmp

Would that work for you?

[dvogt23]

Seems strange, did try it like this:

function get_git_diff()
  -- Define the command to get the git diff
  local command = "git diff"

  -- Use io.popen to run the command and capture its output
  local handle = io.popen(command)
  local result = handle:read("*a") -- Read all output
  handle:close()

  return result
end

require("gen").prompts["Commit summary"] = {
  prompt = "You are an expert developer specialist in creating commits. Provide a super concise one sentence overall changes summary of the user "
    .. get_git_diff()
    .. " output following strictly the next rules: - Do not use any code snippets, imports, file routes or bullets points. - Do not mention the route of file that has been change. - Simply describe the MAIN GOAL of the changes. - Output directly the summary in plain text.",
  replace = true,
}

but getting always like this as output:
The user output shows the main goal of the changes as "Added new features to improve the performance and user experience of the application."

I think I have to chain the output of the first prompt, to this:

You are an expert developer specialist in creating commits messages.
	Your only goal is to retrieve a single commit message. 
	Based on the provided user changes, combine them in ONE SINGLE commit message retrieving the global idea, following strictly the next rules:
	- Always use the next format: \`{type}: {commit_message}\` where \`{type}\` is one of \`feat\`, \`fix\`, \`docs\`, \`style\`, \`refactor\`, \`test\`, \`chore\`, \`revert\`.
	- Output directly only one commit message in plain text.
	- Be as concise as possible. 50 characters max.
	- Do not add any issues numeration nor explain your output.

Is this possible somehow? 😆

[Rasmus-Bertell]

Just wanted to share my solution to this problem if you are still struggling with this. It's missing error handling but should work most of the time.

{
  'David-Kunz/gen.nvim/issues/101',
  opts = { display_mode = 'split' },
  config = function(_, opts)
    local gen = require('gen')

    gen.setup(opts)

    gen.prompts['Commit'] = {
      prompt = function()
        local diff = vim.system({ 'git', 'diff', '--staged' }, { text = true }):wait()

        return [[
          ...prompt...

          Git diff: ]] .. diff.stdout
      end,
      replace = true,
      extract = '```$filetype\n(.-)```',
    }
  end
}

[dvogt23]

Great, thanks @Rasmus-Bertell now Im able to get the summary. I have to chain the output of summary promt to another one for getting a commit message. Do you have an idea?

[Rasmus-Bertell]

No, sorry. This covers my needs so I'm not motivated to explore it further.

[David-Kunz]

Hi @dvogt23 ,

I'm afraid follow-up prompts are not yet possible. Only manually with :Gen Chat.

I'll chink about supporting prompt chains.

[David-Kunz]

For now, would it be possible to put everything in one prompt?

[Rasmus-Bertell]

The problem is that many models have a hard time generating proper commit messages from just the diff, or at least that's what I have noticed, especially if the diff is long. So I think the solution is to first generate a short summary of changes with one prompt and pipe it to another one that makes the actual commit message.