[type] raf (#2699)

packages/utils/event.ts

@@ -0,0 +1,39 @@
+/* eslint-disable no-empty */
+/* eslint-disable getter-return */
+/* eslint-disable import/no-mutable-exports */
+import { noop, isServer } from '.';
+
+type EventHanlder = (event?: Event) => void;
+
+export let supportsPassive = false;
+
+if (!isServer) {
+  try {
+    const opts = {};
+    Object.defineProperty(opts, 'passive', {
+      get() {
+        /* istanbul ignore next */
+        supportsPassive = true;
+      }
+    });
+    window.addEventListener('test-passive', noop, opts);
+  } catch (e) {}
+}
+
+export function on(target: HTMLElement, event: string, handler: EventHanlder, passive = false) {
+  if (!isServer) {
+    target.addEventListener(event, handler, supportsPassive ? { capture: false, passive } : false);
+  }
+}
+
+export function off(target: HTMLElement, event: string, handler: EventHanlder) {
+  !isServer && target.removeEventListener(event, handler);
+}
+
+export function stop(event: Event) {
+  event.stopPropagation();
+}
+
+export function prevent(event: Event) {
+  event.preventDefault();
+}