basichtml/src/utils.js

// Used as Node.TYPE
const ELEMENT_NODE = 1;
const types = {
  ELEMENT_NODE,
  ATTRIBUTE_NODE: 2,
  TEXT_NODE: 3,
  COMMENT_NODE: 8,
  DOCUMENT_NODE: 9,
  DOCUMENT_TYPE_NODE: 10,
  DOCUMENT_FRAGMENT_NODE: 11
};

// void cases
const VOID_ELEMENT = /^area|base|br|col|embed|hr|img|input|keygen|link|menuitem|meta|param|source|track|wbr$/i;
const VOID_ELEMENTS = new RegExp(`<(${VOID_ELEMENT.source})([^>]*?)>`, 'gi');
const VOID_SANITIZER = (_, $1, $2) => `<${$1}${$2}${/\/$/.test($2) ? '' : ' /'}>`;

// shared constants
const connect = (parentNode, child) => {
  if (
    child.nodeType === ELEMENT_NODE &&
    child.isCustomElement && 'connectedCallback' in child &&
    parentNode && parentNode.nodeType !== types.DOCUMENT_FRAGMENT_NODE
  ) {
    child.connectedCallback();
  }
};

const disconnect = (parentNode, child) => {
  if (
    child.nodeType === ELEMENT_NODE &&
    child.isCustomElement && 'disconnectedCallback' in child &&
    parentNode && parentNode.nodeType !== types.DOCUMENT_FRAGMENT_NODE
  ) {
    child.disconnectedCallback();
  }
};

const notifyAttributeChanged = (el, name, oldValue, newValue) => {
  if (
    el.isCustomElement &&
    'attributeChangedCallback' in el &&
    (el.constructor.observedAttributes || []).includes(name)
  ) {
    el.attributeChangedCallback(name, oldValue, newValue);
  }
};

const CSS_SPLITTER = /\s*,\s*/;
function findBySelector(css) {
  switch (css[0]) {
    case '#':
      return this.ownerDocument.getElementById(css.slice(1));
    case '.':
      return this.getElementsByClassName(css.slice(1));
    case '[':
      return findBAttributeName(this, css.replace(/[\[\]]/g, ''), []);
    default:
      return this.getElementsByTagName(css);
  }
}

module.exports = {
  VOID_ELEMENT,
  connect,
  disconnect,
  notifyAttributeChanged,
  types,
  querySelectorAll(css) {
    return [].concat(...('' + css).split(CSS_SPLITTER).map(findBySelector, this));
  },
  voidSanitizer: html => html.replace(VOID_ELEMENTS, VOID_SANITIZER)
};

function findBAttributeName(node, name, all) {
  for (let children = node.children, {length} = children, i = 0; i < length; i++) {
    const child = children[i];
    if (child.hasAttribute(name))
      all.push(child);
    findBAttributeName(child, name, all);
  }
  return all;
}