Function remoteDefaultBranch

x/release/command.go:327–336

remoteDefaultBranch resolves origin's default branch, falling back to "main" when origin/HEAD is not configured locally.

(ctx context.Context)

// remoteDefaultBranch resolves origin's default branch, falling back to "main"
// when origin/HEAD is not configured locally.
func remoteDefaultBranch(ctx context.Context) string {
	out, err := runGit(ctx, "symbolic-ref", "--short", "refs/remotes/origin/HEAD")
	if err != nil {
		fmt.Fprintf(os.Stderr,
			"warning: origin/HEAD is not set; assuming default branch is %q — "+
				"run 'git remote set-head origin -a' if the real default differs\n", "main")
		return "main"
	}
	return strings.TrimPrefix(strings.TrimSpace(out), "origin/")
}

func revParse(ctx context.Context, ref string) (string, error) {
	out, err := runGit(ctx, "rev-parse", ref)