Add __getStackRead to UndoManager

src/canvas/model/Frame.js

@@ -43,6 +43,16 @@ export default Model.extend({
 
     !props.width && this.set(keyAutoW, 1);
     !props.height && this.set(keyAutoH, 1);
+
+    // this._initUm();
+  },
+
+  _initUm() {
+    const um = this.em.get('UndoManager');
+    const component = this.getComponent();
+    if (!um) return;
+    um.add(component);
+    console.log({ component, um });
   },
 
   getComponent() {

src/undo_manager/index.js

@@ -307,6 +307,26 @@ export default () => {
       return result;
     },
 
+    __getStackRead() {
+      const result = {};
+      const createItem = item => {
+        const { type, after, before, object } = item.attributes;
+        return {
+          type,
+          after,
+          before,
+          object
+        };
+      };
+      this.getStack().forEach(item => {
+        const index = item.get('magicFusionIndex');
+        const value = createItem(item);
+        if (!result[index]) result[index] = [value];
+        else result[index].push(value);
+      });
+      return Object.keys(result).map(i => result[i]);
+    },
+
     getPointer() {
       return this.getStack().pointer;
     },