Function watchForOptions

core/src/utils/watch-options.ts:1–18

(
  containerEl: HTMLElement,
  tagName: string,
  onChange: (el: T | undefined) => void
)

export const watchForOptions = <T extends HTMLElement>(
  containerEl: HTMLElement,
  tagName: string,
  onChange: (el: T | undefined) => void
) => {
  if (typeof MutationObserver === 'undefined') {
    return;
  }

  const mutation = new MutationObserver((mutationList) => {
    onChange(getSelectedOption<T>(mutationList, tagName));
  });
  mutation.observe(containerEl, {
    childList: true,
    subtree: true,
  });
  return mutation;
};

const getSelectedOption = <T extends HTMLElement>(mutationList: MutationRecord[], tagName: string): T | undefined => {
  let newOption: T | undefined;