perf(core): avoid yielding for empty resume data

Author: Varixo

packages/qwik/src/core/client/dom-container.ts

@@ -108,6 +108,20 @@ export const processContainerData = (container: IClientContainer): void => {
     ) {
       return;
     }
+    if (
+      !domContainer.element.querySelector('script[type="qwik/state"]') &&
+      !domContainer.document.body.querySelector(QStylesAllSelector)
+    ) {
+      try {
+        runIteratorSync(domContainer.$processContainerData$());
+        markContainerDataReady(domContainer);
+      } catch (error) {
+        domContainer.$containerDataStarted$ = false;
+        domContainer.$containerDataState$ = undefined;
+        throw error;
+      }
+      return;
+    }
     const state: ProcessContainerDataState = {
       $iterator$: domContainer.$processContainerData$(),
       $schedule$: undefined!,
@@ -131,6 +145,15 @@ export const processContainerData = (container: IClientContainer): void => {
   });
 };
 
+function runIteratorSync<T>(iterator: Generator<void, T, void>): T {
+  while (true) {
+    const result = iterator.next();
+    if (result.done) {
+      return result.value;
+    }
+  }
+}
+
 export const onContainerDataReady = (container: IClientContainer, callback: () => void): void => {
   const domContainer = container as DomContainer;
   if (domContainer.$containerDataReady$) {

packages/qwik/src/core/client/process-vnode-data.ts

@@ -94,6 +94,10 @@ export function processVNodeData(document: Document): void {
   }
   qDocument.qVNodeDataStarted = true;
   qDocument.qVNodeData || (qDocument.qVNodeData = new WeakMap<Element, string>());
+  if (!document.querySelector('script[type="qwik/vnode"], [q\\:shadowroot]')) {
+    markVNodeDataReady(qDocument);
+    return;
+  }
   const state: ProcessVNodeDataState = {
     $document$: qDocument,
     $iterator$: processVNodeDataIterator(document),

packages/qwik/src/core/client/process-vnode-data.unit.tsx

@@ -12,6 +12,19 @@ import { Fragment } from '@qwik.dev/core';
 import { TypeIds } from '../shared/serdes/constants';
 
 describe('processVnodeData', () => {
+  it('should finish empty container data without scheduling a chunk', async () => {
+    const document = createDocument() as QDocument;
+    document.body.setAttribute(QContainerAttr, QContainerValue.RESUMED);
+
+    await withYieldingVNodeData(document, async (tasks) => {
+      const container = getDomContainer(document.body) as any;
+
+      expect(document.qVNodeDataReady).toBe(true);
+      expect(container.$containerDataReady$).toBe(true);
+      expect(tasks).toHaveLength(0);
+    });
+  });
+
   it('should yield over multiple chunks and preserve vnode data and refs', async () => {
     const document = createDocument({
       html: `