fix(editor): 丢弃过期 root 快照，避免画布回退与 modelValue 回写死循环

packages/editor/src/initService.ts

@@ -427,12 +427,26 @@ export const initServiceEvents = (
     });
   };
 
+  /**
+   * root 是否已经不是编辑器当前的 root。
+   *
+   * `editorService.set('root', v)` 是同步赋值后再派发 `root-change`，因此派发那一刻 `v` 一定
+   * 就是当前 root；但处理 `root-change` 要等 stage / runtime / 依赖收集等异步过程，期间 root
+   * 可能被新的一次整体替换（外部重设 DSL、更新 root 节点、源码保存等）顶掉，此时手上的 `v`
+   * 已是过期快照，继续用它刷画布或回写给外部都会与新 root 互相覆盖。
+   */
+  const isStaleRoot = (value: MApp | null) => toRaw(editorService.get('root')) !== toRaw(value);
+
   const updateStageDsl = async (value: MApp | null) => {
     const stage = await getStage();
 
     const runtime = await stage.renderer?.getRuntime();
     const app = await getTMagicApp();
 
+    // 等 stage / runtime 就绪期间 root 已被替换：新 root 的刷新可能已经完成，
+    // 再把旧 dsl 推给 runtime 会让画布回退到旧内容
+    if (isStaleRoot(value)) return;
+
     if (!app?.dataSourceManager) {
       runtime?.updateRootConfig?.(cloneDeep(toRaw(value))!);
     }
@@ -449,6 +463,8 @@ export const initServiceEvents = (
 
       await (typeof Worker === 'undefined' ? collectIdle(value.items, true) : depService.collectByWorker(value));
 
+      if (isStaleRoot(value)) return;
+
       const dsl = cloneDeep(toRaw(value));
       if (dsl.dataSources && dsl.dataSourceDeps && app?.dataSourceManager) {
         for (const node of getNodes(getDepNodeIds(dsl.dataSourceDeps), dsl.items)) {
@@ -466,7 +482,7 @@ export const initServiceEvents = (
     depService.addTarget(createDataSourceCondTarget(ds, reactive({})));
   };
 
-  const rootChangeHandler = (value: MApp | null, preValue?: MApp | null) => {
+  const rootChangeHandler = (value: MApp | null) => {
     if (!value) return;
 
     value.codeBlocks = value.codeBlocks || {};
@@ -509,7 +525,13 @@ export const initServiceEvents = (
         editorService.set('page', null);
       }
 
-      if (toRaw(value) !== toRaw(preValue)) {
+      // 上面的 select 是异步的，期间 root 可能已被替换，过期快照不能再回写给外部：
+      // 两次整体替换各自持有一个快照时，回写会把对方的 root 顶掉，外部 modelValue 变化又会
+      // 重新 set root，两条链路无休止地交替下去（表现为编辑器卡死）
+      if (isStaleRoot(value)) return;
+
+      // 外部已经持有这个 root（如本次变化就是 modelValue 传进来的）时无需回写
+      if (toRaw(props.modelValue) !== toRaw(value)) {
         emit('update:modelValue', value);
       }
     })();

packages/editor/tests/unit/initService.spec.ts

@@ -357,7 +357,6 @@ describe('initServiceEvents', () => {
   });
 
   test('rootChange 处理代码块和数据源', async () => {
-    services.editorService.state.root = { id: 'r' };
     mount(WrapEvents({} as any, emit, services));
     const value: any = {
       id: 'r',
@@ -365,6 +364,8 @@ describe('initServiceEvents', () => {
       dataSources: [{ id: 'd1', type: 'base' }],
       items: [],
     };
+    // set('root', v) 是先赋值再派发事件，mock 中同样先对齐 state 再 emit
+    services.editorService.state.root = value;
     services.editorService.emit('root-change', value, null);
     await new Promise((r) => setTimeout(r, 0));
     expect(services.codeBlockService.setCodeDsl).toHaveBeenCalled();
@@ -593,13 +594,15 @@ describe('initServiceEvents', () => {
     services.editorService.state.node = { id: 'n1' };
     mount(WrapEvents({} as any, emit, services));
 
-    services.editorService.emit('root-change', {
+    const value: any = {
       id: 'r',
       items: [{ id: 'n1', type: 'text' }],
       dataSources: [],
       dataSourceDeps: { d1: {} },
       codeBlocks: {},
-    });
+    };
+    services.editorService.state.root = value;
+    services.editorService.emit('root-change', value);
     await new Promise((r) => setTimeout(r, 10));
 
     expect(stage.runtime.updatePageId).toHaveBeenCalledWith('p1');
@@ -608,10 +611,10 @@ describe('initServiceEvents', () => {
   });
 
   test('rootChange items 不是数组时清空依赖', async () => {
-    services.editorService.state.root = { id: 'r' };
     mount(WrapEvents({} as any, emit, services));
 
     const value: any = { id: 'r', dataSourceDeps: { a: {} }, dataSourceCondDeps: { b: {} } };
+    services.editorService.state.root = value;
     services.editorService.emit('root-change', value);
     await new Promise((r) => setTimeout(r, 0));
 
@@ -625,6 +628,7 @@ describe('initServiceEvents', () => {
     mount(WrapEvents({} as any, emit, services));
 
     const value: any = { id: 'r', items: [] };
+    services.editorService.state.root = value;
     services.editorService.emit('root-change', value, { id: 'prev' });
     await new Promise((r) => setTimeout(r, 0));
 
@@ -638,12 +642,44 @@ describe('initServiceEvents', () => {
     services.editorService.getNodeById.mockReturnValue(null);
     mount(WrapEvents({} as any, emit, services));
 
-    services.editorService.emit('root-change', { id: 'r', items: [{ id: 'first', type: 'page' }] });
+    const value: any = { id: 'r', items: [{ id: 'first', type: 'page' }] };
+    services.editorService.state.root = value;
+    services.editorService.emit('root-change', value);
     await new Promise((r) => setTimeout(r, 0));
 
     expect(services.editorService.select).toHaveBeenCalledWith({ id: 'first', type: 'page' });
   });
 
+  test('rootChange 外部已持有该 root 时不回写 modelValue', async () => {
+    services.editorService.getNodeById.mockReturnValue(null);
+    const value: any = { id: 'r', items: [] };
+    mount(WrapEvents({ modelValue: value } as any, emit, services));
+
+    services.editorService.state.root = value;
+    services.editorService.emit('root-change', value);
+    await new Promise((r) => setTimeout(r, 0));
+
+    expect(emit).not.toHaveBeenCalled();
+  });
+
+  test('rootChange 处理期间 root 被替换：不刷旧 dsl 也不回写过期快照', async () => {
+    const app: any = { dsl: {}, dataSourceManager: mkDataSourceManager() };
+    const stage = mkReadyStage(app);
+    services.editorService.state.stage = stage;
+    services.editorService.getNodeById.mockReturnValue(null);
+    mount(WrapEvents({} as any, emit, services));
+
+    const value: any = { id: 'r', items: [{ id: 'n1', type: 'text' }], dataSources: [], codeBlocks: {} };
+    services.editorService.state.root = value;
+    services.editorService.emit('root-change', value);
+    // 异步处理还没跑完，root 已被新的一次整体替换顶掉
+    services.editorService.state.root = { id: 'r', items: [], dataSources: [], codeBlocks: {} };
+    await new Promise((r) => setTimeout(r, 10));
+
+    expect(stage.runtime.updateRootConfig).not.toHaveBeenCalled();
+    expect(emit).not.toHaveBeenCalled();
+  });
+
   test('update 事件：ROOT 节点、无 propPath、命中已收集依赖三种分支', async () => {
     services.editorService.state.root = { id: 'r', items: [] };
     services.depService.getTargets.mockReturnValue({