Function unsafeIndexRootReason

src/directory.ts:255–285

(projectRoot: string)

 * The returned string is a human phrase that slots into "… looks like {reason}".
 */
export function unsafeIndexRootReason(projectRoot: string): string | null {
  const resolve = (p: string): string => {
    try {
      return fs.realpathSync(path.resolve(p));
    } catch {
      return path.resolve(p);
    }
  };
  const resolved = resolve(projectRoot);

  // Filesystem root: `/` on POSIX, a drive root like `C:\` on Windows.
  if (path.parse(resolved).root === resolved) {
    return 'the filesystem root';
  }

  const home = resolve(os.homedir());
  // Case-insensitive on macOS/Windows (case-preserving but case-insensitive FS).
  const norm = (p: string): string =>
    process.platform === 'darwin' || process.platform === 'win32' ? p.toLowerCase() : p;
  const r = norm(resolved);
  const h = norm(home);

  if (r === h) {
    return 'your home directory';
  }
  // An ancestor of home (e.g. `/Users`, `/home`) — even broader than home.
  if (h.startsWith(r + path.sep)) {
    return 'a parent of your home directory';
  }
  return null;
}

/**
 * `dev:ino` for a path, or null if it can't be stat'd or the platform doesn't