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/**
* Tests for passive scroll support
* Copied from https://github.com/WICG/EventListenerOptions/blob/gh-pages/explainer.md
*/
let supportsPassiveOption = false;
try {
const opts = Object.defineProperty({}, 'passive', {
get: () => {
supportsPassiveOption = true;
},
});
window.addEventListener('test', null, opts);
} catch (e) {
/* */
}
/**
* Attempts to add a passive scroll listener if possible,
* otherwise adds a non-capture listeners
*/
export const addEventListener = (target, type, handler) => {
let optionsOrCapture;
if (supportsPassiveOption) {
optionsOrCapture = { passive: true };
} else {
optionsOrCapture = false;
}
target.addEventListener(type, handler, optionsOrCapture);
};
export const removeEventListener = (target, type, handler) => {
let optionsOrCapture;
if (supportsPassiveOption) {
optionsOrCapture = { passive: true };
} else {
optionsOrCapture = false;
}
target.removeEventListener(type, handler, optionsOrCapture);
};
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