Function validateConfigKeyPath

src/core/config-schema.ts:44–68

(path: string)

 * Unknown top-level keys are rejected unless explicitly allowed by the caller.
 */
export function validateConfigKeyPath(path: string): { valid: boolean; reason?: string } {
  const rawKeys = path.split('.');

  if (rawKeys.length === 0 || rawKeys.some((key) => key.trim() === '')) {
    return { valid: false, reason: 'Key path must not be empty' };
  }

  const rootKey = rawKeys[0];
  if (!KNOWN_TOP_LEVEL_KEYS.has(rootKey)) {
    return { valid: false, reason: `Unknown top-level key "${rootKey}"` };
  }

  if (rootKey === 'featureFlags') {
    if (rawKeys.length > 2) {
      return { valid: false, reason: 'featureFlags values are booleans and do not support nested keys' };
    }
    return { valid: true };
  }

  if (rawKeys.length > 1) {
    return { valid: false, reason: `"${rootKey}" does not support nested keys` };
  }

  return { valid: true };
}

/**
 * Get a nested value from an object using dot notation.