git-branch-clean/main.js

const yml = require('require-yml');
const path = require('path');
const fs = require('fs-extra');
const simpleGit = require('simple-git');
const { promisify } = require('util');

let conf = yml(path.join(__dirname, 'config.yml'));
const localConfFile = path.join(__dirname, 'config.local.yml');
if (fs.existsSync(localConfFile))
	conf = Object.assign({}, conf, yml(localConfFile));

const git = simpleGit(conf.path);

const gitBranch = promisify(git.branch.bind(git));
const gitPush = promisify(git.push.bind(git));

async function main() {
	try {
		await git.fetch(['--prune']);
		let branches = (await gitBranch(['-r', '--merged', 'HEAD'])).all;
		const excludedBranches = ['test', 'master', 'dev'];
		branches = branches.map((branch) => {return branch.substring(7, branch.length)});
		branches = branches.filter((element) => !excludedBranches.includes(element));

		for (let branch of branches) {
			await gitPush(['origin', '--delete', branch]);
			console.log(`Branch deleted: ${branch}`);
		}

		console.log('Merged branches deleted successfully!');
	} catch (err) {
		console.error('[Error]', err);
	}
}

main();