Function getDivergedCommit

packages/git/src/index.ts:48–56

(cwd: string, ref: string)

// Find the commit where we diverged from `ref` at using `git merge-base`
export async function getDivergedCommit(cwd: string, ref: string) {
  const cmd = await spawn("git", ["merge-base", ref, "HEAD"], { cwd });
  if (cmd.code !== 0) {
    throw new Error(
      `Failed to find where HEAD diverged from "${ref}". Does "${ref}" exist and it's synced with remote?`
    );
  }
  return cmd.stdout.toString().trim();
}

/**
 * Get the SHAs for the commits that added files, including automatically