fixChromeTouchEventListener.js

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// Fix for https://github.com/WICG/interventions/issues/18
// TL/DR: Chrome made {passive:true} the default for touch events, breaking any site that
// deliberately listened to them to call event.preventDefault().

window.addEventListener("options-test", null, Object.defineProperty({}, "capture", {
	get: function() {
		var oldEventListener = document.addEventListener;

		if (!oldEventListener.isTouched) {
			var addEventListenerTouch = function(eventType, listener, options, wantsUntrusted) {
				switch (eventType) {
					case "touchstart":
					case "touchmove":
					case "touchend":
						if (options === true || options === false) {
							options = {
								capture: options
							}
						} else if (!options) {
							options = {};
						}
						if (!options.passive) {
							options.passive = false;
						}
						break;
				}
				// Just in case the spec changes to allow its return to be used and this patch is still in use...
				return oldEventListener.call(this, eventType, listener, options, wantsUntrusted);
			};

			addEventListenerTouch.isTouched = true;
			Object.defineProperty(document, "addEventListener", {
				value: addEventListenerTouch,
				configurable: true
			});
			Object.defineProperty(document.body, "addEventListener", {
				value: addEventListenerTouch,
				configurable: true
			});
		}
	}
}));