fix: finding projections after client partial rerender

.changeset/sweet-candles-arrive.md

@@ -0,0 +1,5 @@
+---
+'@qwik.dev/core': patch
+---
+
+fix: finding projections after client partial rerender

packages/qwik/src/core/client/vnode.ts

@@ -1847,6 +1847,8 @@ function materializeFromVNodeData(
     return !nodeIsElement || (nodeIsElement && shouldSkipElement(node));
   };
 
+  let components: VirtualVNode[] | null = null;
+
   processVNodeData(vData, (peek, consumeValue, consume, getChar, nextToConsumeIdx) => {
     if (isNumber(peek())) {
       // Element counts get encoded as numbers.
@@ -1871,6 +1873,7 @@ function materializeFromVNodeData(
     } else if (peek() === VNodeDataChar.SCOPED_STYLE) {
       vParent.setAttr(QScopedStyle, consumeValue(), null);
     } else if (peek() === VNodeDataChar.RENDER_FN) {
+      (components ||= []).push(vParent as VirtualVNode);
       vParent.setAttr(OnRenderProp, consumeValue(), null);
     } else if (peek() === VNodeDataChar.ID) {
       if (!container) {
@@ -1956,6 +1959,15 @@ function materializeFromVNodeData(
       // Text nodes get encoded as alphanumeric characters.
     }
   });
+  if (components) {
+    if (!container) {
+      container = getDomContainer(element);
+    }
+    for (const component of components as VirtualVNode[]) {
+      container.ensureProjectionResolved(component);
+    }
+    components = null;
+  }
   vParent.lastChild = vLast;
   return vFirst!;
 }

packages/qwik/src/core/tests/projection.spec.tsx

@@ -22,8 +22,10 @@ import { domRender, ssrRenderToDom, trigger } from '@qwik.dev/core/testing';
 import { cleanupAttrs } from 'packages/qwik/src/testing/element-fixture';
 import { beforeEach, describe, expect, it } from 'vitest';
 import { vnode_locate } from '../client/vnode';
-import { HTML_NS, QContainerAttr, SVG_NS } from '../shared/utils/markers';
+import { HTML_NS, QContainerAttr, QDefaultSlot, SVG_NS } from '../shared/utils/markers';
 import { QContainerValue } from '../shared/types';
+import { VNodeFlags } from '../client/types';
+import { VirtualVNode } from '../client/vnode-impl';
 
 const DEBUG = false;
 
@@ -1572,6 +1574,23 @@ describe.each([
         </div>
       );
     });
+
+    it('should resolve projection when component is resumed', async () => {
+      const Child = component$(() => {
+        return <div></div>;
+      });
+      const Cmp = component$(() => {
+        return <Slot />;
+      });
+      const { vNode } = await render(
+        <Cmp>
+          <Child />
+        </Cmp>,
+        { debug: DEBUG }
+      );
+      expect((vNode!.flags & VNodeFlags.Resolved) === VNodeFlags.Resolved).toBe(true);
+      expect(vNode?.getProp(QDefaultSlot, null)).toBeInstanceOf(VirtualVNode);
+    });
   });
 
   describe('q:template', () => {

packages/qwik/src/core/tests/use-visible-task.spec.tsx

@@ -19,6 +19,9 @@ import { domRender, ssrRenderToDom, trigger } from '@qwik.dev/core/testing';
 import { describe, expect, it } from 'vitest';
 import { ErrorProvider } from '../../testing/rendering.unit-util';
 import { delay } from '../shared/utils/promises';
+import { ELEMENT_SEQ } from '../../server/qwik-copy';
+import { Task, TaskFlags } from '../use/use-task';
+import { USE_ON_LOCAL } from '../shared/utils/markers';
 
 const debug = false; //true;
 Error.stackTraceLimit = 100;
@@ -796,6 +799,43 @@ describe.each([
   });
 
   describe('regression', () => {
+    it('should not double-register events on component re-render', async () => {
+      const Cmp = component$(() => {
+        const count = useSignal(0);
+
+        useVisibleTask$(() => {});
+        // component rerender
+        count.value;
+
+        return (
+          <div>
+            <button onClick$={() => count.value++}>Click</button>
+          </div>
+        );
+      });
+
+      const { document, vNode, container } = await render(<Cmp />, { debug });
+
+      if (render === ssrRenderToDom) {
+        await trigger(document.body, 'div', 'qvisible');
+      }
+      const seq = vNode!.getProp<any[]>(ELEMENT_SEQ, container.$getObjectById$)!;
+      const task = seq.find((task) => task instanceof Task)!;
+      expect((task.$flags$ & TaskFlags.EVENTS_REGISTERED) === TaskFlags.EVENTS_REGISTERED).toBe(
+        false
+      );
+      if (render === ssrRenderToDom) {
+        // only on SSR after resuming we have no useOn props
+        expect(vNode!.getProp(USE_ON_LOCAL, null)).toBeNull();
+      }
+
+      await trigger(document.body, 'button', 'click');
+      expect((task.$flags$ & TaskFlags.EVENTS_REGISTERED) === TaskFlags.EVENTS_REGISTERED).toBe(
+        true
+      );
+      expect(vNode!.getProp(USE_ON_LOCAL, null)).not.toBeNull();
+    });
+
     it('#1717 - custom hooks should work', async () => {
       const Issue1717 = component$(() => {
         const val1 = useDelay('valueA');

packages/qwik/src/core/use/use-task.ts

@@ -23,6 +23,7 @@ export const enum TaskFlags {
   RESOURCE = 1 << 2,
   DIRTY = 1 << 3,
   RENDER_BLOCKING = 1 << 4,
+  EVENTS_REGISTERED = 1 << 5,
 }
 
 // <docs markdown="../readme.md#Tracker">

packages/qwik/src/core/use/use-visible-task.ts

@@ -31,23 +31,24 @@ export const useVisibleTaskQrl = (qrl: QRL<TaskFn>, opts?: OnVisibleTaskOptions)
   const { val, set, i, iCtx } = useSequentialScope<Task<TaskFn>>();
   const eagerness = opts?.strategy ?? 'intersection-observer';
   if (val) {
-    if (isServerPlatform()) {
-      useRunTask(val, eagerness);
+    if (!(val.$flags$ & TaskFlags.EVENTS_REGISTERED) && !isServerPlatform()) {
+      val.$flags$ |= TaskFlags.EVENTS_REGISTERED;
+      useRegisterTaskEvents(val, eagerness);
     }
     return;
   }
   assertQrl(qrl);
 
   const task = new Task(TaskFlags.VISIBLE_TASK, i, iCtx.$hostElement$, qrl, undefined, null);
   set(task);
-  useRunTask(task, eagerness);
+  useRegisterTaskEvents(task, eagerness);
   if (!isServerPlatform()) {
     (qrl as QRLInternal).resolve(iCtx.$element$);
     iCtx.$container$.$scheduler$(ChoreType.VISIBLE, task);
   }
 };
 
-export const useRunTask = (task: Task, eagerness: VisibleTaskStrategy | undefined) => {
+export const useRegisterTaskEvents = (task: Task, eagerness: VisibleTaskStrategy | undefined) => {
   if (eagerness === 'intersection-observer') {
     useOn('qvisible', getTaskHandlerQrl(task));
   } else if (eagerness === 'document-ready') {