vanillajs-browser-helpers/eventOptionsSupported.mjs

Collection of convenience code snippets (helpers) that aims to make it a little easier to work with vanilla JS in the browser

let supported;
/**
 * Detect if options are supported by the add-/removeEventListener methods
 *
 * @param recheck - Force the function to check the support again
 * @return Are event binding options supported or not
 */
export default function eventOptionsSupported(recheck) {
    if (supported != null && !recheck) {
        return supported;
    }
    supported = false;
    try {
        const opts = Object.defineProperty({}, 'passive', {
            get() {
                supported = true;
                return supported;
            }
        });
        const noop = () => undefined;
        document.addEventListener('verify-support', noop, opts);
        document.removeEventListener('verify-support', noop, opts);
    }
    catch { }
    return supported;
}