fix: object-assign errors

.gitignore

@@ -7,4 +7,5 @@ temp
 dist
 # todo - get story book only when releasing.
 storybook-static
-yarn.lock
+yarn.lock
+package-lock.json

.prettierrc

@@ -1,4 +1,4 @@
 {
   "arrowParens": "always",
-  "semi": false
+  "semi": true
 }

src/react-sortable.tsx

@@ -49,14 +49,12 @@ export class ReactSortable<T extends ItemInterface> extends Component<
     this.ref = createRef<HTMLElement>();
 
     // make all state false because we can't change sortable unless a mouse gesture is made.
-    const newList = [...props.list];
-
-    newList.forEach((item: T) => {
+    const newList = [...props.list].map((item) =>
       Object.assign(item, {
         chosen: false,
         selected: false,
-      });
-    })
+      })
+    );
 
     props.setList(newList, this.sortable, store);
     invariant(
@@ -120,8 +118,8 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
     const dataid = dataIdAttr || "data-id";
     /* eslint-disable-next-line */
     return Children.map(children as ReactElement<any>[], (child, index) => {
-      if (child === undefined) return undefined
-      
+      if (child === undefined) return undefined;
+
       const item = list[index] || {};
       const { className: prevClassName } = child.props;
 
@@ -239,13 +237,12 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
     const customs = createCustoms(evt, otherList);
     removeNodes(customs);
 
-    const newList = handleStateAdd(customs, list, evt, clone)
-
-    newList.forEach((item) => {
+    const newList = handleStateAdd(customs, list, evt, clone).map((item) =>
       Object.assign(item, {
         selected: false,
-      });
-    });
+      })
+    );
+
     setList(newList, this.sortable, store);
   }
 
@@ -296,11 +293,12 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
     }
 
     // remove item.selected from list
-    newList.forEach((item: T) => {
+    newList = newList.map((item: T) =>
       Object.assign(item, {
         selected: false,
-      });
-    })
+      })
+    );
+
     setList(newList, this.sortable, store);
   }
 
@@ -324,25 +322,27 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
   onChoose(evt: SortableEvent): void {
     const { list, setList } = this.props;
     const newList = list.map((item, index) => {
+      let newItem = item;
       if (index === evt.oldIndex) {
-        Object.assign(item, {
+        newItem = Object.assign(item, {
           chosen: true,
         });
       }
-      return item;
+      return newItem;
     });
     setList(newList, this.sortable, store);
   }
 
   onUnchoose(evt: SortableEvent): void {
     const { list, setList } = this.props;
     const newList = list.map((item, index) => {
+      let newItem = item;
       if (index === evt.oldIndex) {
-        Object.assign(item, {
+        newItem = Object.assign(newItem, {
           chosen: false,
         });
       }
-      return item;
+      return newItem;
     });
     setList(newList, this.sortable, store);
   }
@@ -354,12 +354,12 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
 
   onSelect(evt: MultiDragEvent): void {
     const { list, setList } = this.props;
-    const newList = [...list];
-    newList.forEach((item) => {
+    const newList = list.map((item) =>
       Object.assign(item, {
-        chosen: false,
-      });
-    });
+        selected: false,
+      })
+    );
+
     evt.newIndicies.forEach((curr) => {
       const index = curr.index;
       if (index === -1) {
@@ -376,12 +376,11 @@ Please read the updated README.md at https://github.com/SortableJS/react-sortabl
 
   onDeselect(evt: MultiDragEvent): void {
     const { list, setList } = this.props;
-    const newList = [...list];
-    newList.forEach((item) => {
+    const newList = list.map((item) =>
       Object.assign(item, {
-        chosen: false,
-      });
-    });
+        selected: false,
+      })
+    );
     evt.newIndicies.forEach((curr) => {
       const index = curr.index;
       if (index === -1) return;