✨ delay new view update

Author: BenoitZugmeyer

packages/core/src/tools/utils/functionUtils.ts

@@ -1,3 +1,4 @@
+import { monitorError } from '../monitor'
 import type { TimeoutId } from '../timer'
 import { setTimeout, clearTimeout } from '../timer'
 
@@ -43,3 +44,7 @@ export function throttle<T extends (...args: any[]) => void>(
 
 // eslint-disable-next-line @typescript-eslint/no-empty-function
 export function noop() {}
+
+export function enqueueMicroTask(callback: () => void) {
+  Promise.resolve().then(callback).catch(monitorError)
+}

packages/rum-core/src/domain/view/trackViews.spec.ts

@@ -107,6 +107,15 @@ describe('view lifecycle', () => {
     changeLocation = viewTest.changeLocation
   })
 
+  it('notifies a View update asynchronously', () => {
+    const { getViewUpdateCount } = viewTest
+
+    expect(getViewUpdateCount()).toBe(0)
+    clock.tick(0)
+
+    expect(getViewUpdateCount()).toBe(1)
+  })
+
   describe('expire session', () => {
     it('should end the view when the session expires', () => {
       const { lifeCycle, getViewEndCount } = viewTest

packages/rum-core/src/domain/view/trackViews.ts

@@ -26,6 +26,7 @@ import {
   setTimeout,
   Observable,
   createContextManager,
+  enqueueMicroTask,
 } from '@datadog/browser-core'
 import type { ViewCustomTimings } from '../../rawRumEvent.types'
 import { ViewLoadingType } from '../../rawRumEvent.types'
@@ -287,7 +288,11 @@ function newView(
   })
 
   // Initial view update
-  triggerViewUpdate()
+  enqueueMicroTask(() => {
+    if (documentVersion === 0) {
+      triggerViewUpdate()
+    }
+  })
 
   // View context update should always be throttled
   contextManager.changeObservable.subscribe(scheduleViewUpdate)