Function _parseConfig

src/purify.ts:472–702

(cfg: Config = {})

   */
  // eslint-disable-next-line complexity
  const _parseConfig = function (cfg: Config = {}): void {
    if (CONFIG && CONFIG === cfg) {
      return;
    }

    /* Shield configuration object from tampering */
    if (!cfg || typeof cfg !== 'object') {
      cfg = {};
    }

    /* Shield configuration object from prototype pollution */
    cfg = clone(cfg);

    PARSER_MEDIA_TYPE =
      // eslint-disable-next-line unicorn/prefer-includes
      SUPPORTED_PARSER_MEDIA_TYPES.indexOf(cfg.PARSER_MEDIA_TYPE) === -1
        ? DEFAULT_PARSER_MEDIA_TYPE
        : cfg.PARSER_MEDIA_TYPE;

    // HTML tags and attributes are not case-sensitive, converting to lowercase. Keeping XHTML as is.
    transformCaseFunc =
      PARSER_MEDIA_TYPE === 'application/xhtml+xml'
        ? stringToString
        : stringToLowerCase;

    /* Set configuration parameters */
    ALLOWED_TAGS = objectHasOwnProperty(cfg, 'ALLOWED_TAGS')
      ? addToSet({}, cfg.ALLOWED_TAGS, transformCaseFunc)
      : DEFAULT_ALLOWED_TAGS;
    ALLOWED_ATTR = objectHasOwnProperty(cfg, 'ALLOWED_ATTR')
      ? addToSet({}, cfg.ALLOWED_ATTR, transformCaseFunc)
      : DEFAULT_ALLOWED_ATTR;
    ALLOWED_NAMESPACES = objectHasOwnProperty(cfg, 'ALLOWED_NAMESPACES')
      ? addToSet({}, cfg.ALLOWED_NAMESPACES, stringToString)
      : DEFAULT_ALLOWED_NAMESPACES;
    URI_SAFE_ATTRIBUTES = objectHasOwnProperty(cfg, 'ADD_URI_SAFE_ATTR')
      ? addToSet(
          clone(DEFAULT_URI_SAFE_ATTRIBUTES),
          cfg.ADD_URI_SAFE_ATTR,
          transformCaseFunc
        )
      : DEFAULT_URI_SAFE_ATTRIBUTES;
    DATA_URI_TAGS = objectHasOwnProperty(cfg, 'ADD_DATA_URI_TAGS')
      ? addToSet(
          clone(DEFAULT_DATA_URI_TAGS),
          cfg.ADD_DATA_URI_TAGS,
          transformCaseFunc
        )
      : DEFAULT_DATA_URI_TAGS;
    FORBID_CONTENTS = objectHasOwnProperty(cfg, 'FORBID_CONTENTS')
      ? addToSet({}, cfg.FORBID_CONTENTS, transformCaseFunc)
      : DEFAULT_FORBID_CONTENTS;
    FORBID_TAGS = objectHasOwnProperty(cfg, 'FORBID_TAGS')
      ? addToSet({}, cfg.FORBID_TAGS, transformCaseFunc)
      : clone({});
    FORBID_ATTR = objectHasOwnProperty(cfg, 'FORBID_ATTR')
      ? addToSet({}, cfg.FORBID_ATTR, transformCaseFunc)
      : clone({});