fix undo-redo

src/Struct/Item.js

@@ -55,14 +55,16 @@ export default class Item {
   /**
    * Copy the effect of struct
    */
-  _copy () {
+  _copy (undeleteChildren, copyPosition) {
     let struct = new this.constructor()
-    struct._origin = this._left
-    struct._left = this._left
-    struct._right = this
-    struct._right_origin = this
-    struct._parent = this._parent
-    struct._parentSub = this._parentSub
+    if (copyPosition) {
+      struct._origin = this._left
+      struct._left = this._left
+      struct._right = this
+      struct._right_origin = this
+      struct._parent = this._parent
+      struct._parentSub = this._parentSub
+    }
     return struct
   }
   get _lastId () {

src/Struct/ItemJSON.js

@@ -6,8 +6,8 @@ export default class ItemJSON extends Item {
     super()
     this._content = null
   }
-  _copy () {
-    let struct = super._copy()
+  _copy (undeleteChildren, copyPosition) {
+    let struct = super._copy(undeleteChildren, copyPosition)
     struct._content = this._content
     return struct
   }

src/Struct/ItemString.js

@@ -6,8 +6,8 @@ export default class ItemString extends Item {
     super()
     this._content = null
   }
-  _copy () {
-    let struct = super._copy()
+  _copy (undeleteChildren, copyPosition) {
+    let struct = super._copy(undeleteChildren, copyPosition)
     struct._content = this._content
     return struct
   }

src/Struct/Type.js

@@ -79,15 +79,16 @@ export default class Type extends Item {
       type = type._parent
     }
   }
-  _copy (undeleteChildren) {
-    let copy = super._copy()
+  _copy (undeleteChildren, copyPosition) {
+    let copy = super._copy(undeleteChildren, copyPosition)
     let map = new Map()
     copy._map = map
     for (let [key, value] of this._map) {
       if (undeleteChildren.has(value) || !value.deleted) {
-        let _item = value._copy(undeleteChildren)
+        let _item = value._copy(undeleteChildren, false)
         _item._parent = copy
-        map.set(key, value._copy(undeleteChildren))
+        _item._parentSub = key
+        map.set(key, _item)
       }
     }
     let prevUndeleted = null
@@ -95,7 +96,7 @@ export default class Type extends Item {
     let item = this._start
     while (item !== null) {
       if (undeleteChildren.has(item) || !item.deleted) {
-        let _item = item._copy(undeleteChildren)
+        let _item = item._copy(undeleteChildren, false)
         _item._left = prevUndeleted
         _item._origin = prevUndeleted
         _item._right = null