Function resolveWithinProject

packages/core/src/safePath.ts:69–72

(base: string, relativePath: string)

 * let the symlink-escape slip past several call sites historically.
 */
export function resolveWithinProject(base: string, relativePath: string): string | null {
  const resolved = resolve(base, relativePath);
  return isSafePath(base, resolved) ? resolved : null;
}