GenAI Git Commits

Generating a git commit message is quickly become a classic GenAI application for developers.

To help with this, we will craft a GenAIScript script.

The script acts as a regular node.js automation script and uses runPrompt
to issue calls to the LLM and ask the user to confirm the generated text.

🔍 Explaining the Script

We start by using git check if there are any staged changes in the Git repository:

let { stdout } = await host.exec("git", ["diff", "--cached"]) 

If no changes are staged, we ask the user if they want to stage all changes. If the user confirms, we stage all changes. Otherwise, we bail out.

 const stage = await host.confirm("Stage all changes?", { default: true, }) if (stage) { await host.exec("git", ["add", "."]) stdout = (await host.exec("git", ["diff", "--cached"])).stdout } if (!stdout) cancel("no staged changes") 

We generate an initial commit message using the staged changes:

message = ( await runPrompt( (_) => { _.def("GIT_DIFF", stdout, { maxTokens: 20000 }) _.$`GIT_DIFF is a diff of all staged changes, coming from the command: \`\`\` git diff --cached \`\`\` Please generate a concise, one-line commit message for these changes. - do NOT add quotes` }, { temperature: 0.8 } ) ).text 

The prompt configuration above indicates that the message should be concise,
related to the "git diff --cached" output, and should not include quotes.

User chooses how to proceed with the generated message:

 choice = await host.select( message, [ { name: "commit", value: "commit", description: "accept message and commit" }, ... ]) 

Options are given to edit or regenerate the message. If the user chooses to edit the message, we ask them to input a new message:

 if (choice === "edit") { message = await host.input("Edit commit message", { required: true, }) choice = "commit" } 

If the user chooses to commit the message, we commit the changes:

 if (choice === "commit" && message) { console.log((await host.exec("git", ["commit", "-m", message])).stdout) } 

🚀 Running the Script

You can run this script using the CLI.

genaiscript run gcm 

If you are using npx,

npx --yes genaiscript run gcm 

This command will run the script, and guide you through the process of generating and committing a Git message using AI, making your commits more informative and consistent.

You can wrap this command in a gcm.sh file or in your package script section in package.json:

{ "devDependencies": { "genaiscript": "..." }, "scripts": { "gcm": "genaiscript run gcm" } } 

Then you can run the script using:

npm run gcm 

Acknowledgements

This script was inspired from Karpathy's commit message generator.