@netlify/config/lib/env/git.js

Netlify config module

import { execa } from 'execa';
import { removeFalsy } from '../utils/remove_falsy.js';
// Retrieve git-related information for use in environment variables.
// git is optional and there might be not git repository.
// We purposely keep this decoupled from the git utility.
export const getGitEnv = async function (buildDir, branch) {
    const [COMMIT_REF, CACHED_COMMIT_REF] = await Promise.all([
        git(['rev-parse', 'HEAD'], buildDir),
        git(['rev-parse', 'HEAD^'], buildDir),
    ]);
    const gitEnv = { BRANCH: branch, HEAD: branch, COMMIT_REF, CACHED_COMMIT_REF, PULL_REQUEST: 'false' };
    const gitEnvA = removeFalsy(gitEnv);
    return gitEnvA;
};
const git = async function (args, cwd) {
    try {
        const { stdout } = await execa('git', args, { cwd });
        return stdout;
    }
    catch {
        // continue regardless error
    }
};