@react-aria/utils/src/isFocusable.ts

Spectrum UI components in React

const focusableElements = [
  'input:not([disabled]):not([type=hidden])',
  'select:not([disabled])',
  'textarea:not([disabled])',
  'button:not([disabled])',
  'a[href]',
  'area[href]',
  'summary',
  'iframe',
  'object',
  'embed',
  'audio[controls]',
  'video[controls]',
  '[contenteditable]:not([contenteditable^="false"])'
];

const FOCUSABLE_ELEMENT_SELECTOR = focusableElements.join(':not([hidden]),') + ',[tabindex]:not([disabled]):not([hidden])';

focusableElements.push('[tabindex]:not([tabindex="-1"]):not([disabled])');
const TABBABLE_ELEMENT_SELECTOR = focusableElements.join(':not([hidden]):not([tabindex="-1"]),');

export function isFocusable(element: Element): boolean {
  return element.matches(FOCUSABLE_ELEMENT_SELECTOR);
}

export function isTabbable(element: Element): boolean {
  return element.matches(TABBABLE_ELEMENT_SELECTOR);
}