espretto

const kebabCase = (camelCased: string) =>
  camelCased.replace(/([a-z])([A-Z])/g, "$1-$2").toLowerCase();

export const toCssText = (styles: object) =>
  Object.keys(styles)
    // @ts-ignore: trust input is a CSSStyleDeclaration
    .flatMap(prop => [kebabCase(prop), ":", styles[prop], ";"])
    .join("");

espretto

const htmlSpecialChars = [
  ["&", "&"],
  [">", ">"],
  ["<", "&lt;"],
];

const encode = (data: string) =>
  htmlSpecialChars.reduce(
    (data, [char, entity]) => data.replaceAll(char, entity),

espretto

export function onNode(root, selector, handler) {
  const target = root.querySelector(selector);
  if (target) return handler(target);

  new MutationObserver((records, observer) => {
    const target = records
      .filter(record => record.type === "childList")
      .flatMap(record => record.addedNodes)
      .find(node => node.nodeType === 1 && node.matches(selector));

espretto

function isObject(obj: any) {
  return typeof obj === "object" && obj !== null;
}

function isPlainObject(obj: any) {
  return Object.getPrototypeOf(obj).constructor === Object;
}

/**
 * used to deep merge json serializable objects.