Method _applySimpleSelectorScope

packages/compiler/src/shadow_css.ts:704–728

(
    selector: string,
    scopeSelector: string,
    hostSelector: string,
  )

  // scope via name and [is=name]
  private _applySimpleSelectorScope(
    selector: string,
    scopeSelector: string,
    hostSelector: string,
  ): string {
    // In Android browser, the lastIndex is not reset when the regex is used in String.replace()
    _polyfillHostRe.lastIndex = 0;
    if (_polyfillHostRe.test(selector)) {
      const replaceBy = `[${hostSelector}]`;
      let result = selector;
      while (result.match(_polyfillHostNoCombinatorRe)) {
        result = result.replace(_polyfillHostNoCombinatorRe, (_hnc, selector) => {
          return selector.replace(
            /([^:\)]*)(:*)(.*)/,
            (_: string, before: string, colon: string, after: string) => {
              return before + replaceBy + colon + after;
            },
          );
        });
      }
      return result.replace(_polyfillHostRe, replaceBy);
    }

    return scopeSelector + ' ' + selector;
  }

  // return a selector with [name] suffix on each simple selector
  // e.g. .foo.bar > .zot becomes .foo[name].bar[name] > .zot[name]  /** @internal */