fix(reactivity): fix effect not schedule when trigger maybedirty

close #11236

packages/reactivity/__tests__/computed.spec.ts

@@ -765,6 +765,40 @@ describe('reactivity/computed', () => {
     expect(COMPUTED_SIDE_EFFECT_WARN).toHaveBeenWarned()
   })
 
+  // #11236
+  it('should schedule effect when trigger maybedirty', async () => {
+    const foo = ref<any>({})
+
+    const bar = computed(() => {
+      foo.value.bar ??= {}
+      return foo.value.bar
+    })
+
+    const baz = computed(() => {
+      bar.value.baz ??= []
+      return bar.value.baz
+    })
+
+    const qux = computed(() => baz.value.at(-1) === 2)
+
+    const Comp = {
+      render: () => h('div', [JSON.stringify(qux.value)]),
+    }
+    const root = nodeOps.createElement('div')
+    render(h(Comp), root)
+    await nextTick()
+    expect(serializeInner(root)).toBe('<div>false</div>')
+
+    baz.value.push(1)
+    await nextTick()
+    expect(serializeInner(root)).toBe('<div>false</div>')
+
+    baz.value.push(2)
+    await nextTick()
+    expect(serializeInner(root)).toBe('<div>true</div>')
+    expect(COMPUTED_SIDE_EFFECT_WARN).toHaveBeenWarned()
+  })
+
   it('debug: onTrigger (ref)', () => {
     let events: DebuggerEvent[] = []
     const onTrigger = vi.fn((e: DebuggerEvent) => {

packages/reactivity/src/effect.ts

@@ -325,15 +325,7 @@ export function triggerEffects(
       effect._dirtyLevel < dirtyLevel &&
       (tracking ??= dep.get(effect) === effect._trackId)
     ) {
-      effect._shouldSchedule ||= effect._dirtyLevel === DirtyLevels.NotDirty
-      // always schedule if the computed is original side effect
-      // since we know it is actually dirty
-      if (
-        effect.computed &&
-        effect._dirtyLevel === DirtyLevels.MaybeDirty_ComputedSideEffect_Origin
-      ) {
-        effect._shouldSchedule = true
-      }
+      resolveSchedule(effect, dirtyLevel)
       effect._dirtyLevel = dirtyLevel
     }
     if (
@@ -358,3 +350,21 @@ export function triggerEffects(
   }
   resetScheduling()
 }
+
+function resolveSchedule(effect: ReactiveEffect, dirtyLevel: DirtyLevels) {
+  effect._shouldSchedule ||= effect._dirtyLevel === DirtyLevels.NotDirty
+  // always schedule if the computed is original side effect
+  // since we know it is actually dirty
+  if (
+    effect.computed &&
+    effect._dirtyLevel === DirtyLevels.MaybeDirty_ComputedSideEffect_Origin
+  ) {
+    effect._shouldSchedule = true
+  }
+  if (
+    effect._dirtyLevel === DirtyLevels.MaybeDirty_ComputedSideEffect &&
+    dirtyLevel > DirtyLevels.MaybeDirty_ComputedSideEffect
+  ) {
+    effect._shouldSchedule = true
+  }
+}