Fix useTreeData subtree move validation

packages/react-stately/src/data/useTreeData.ts

@@ -378,6 +378,14 @@ export function useTreeData<T extends object>(options: TreeOptions<T>): TreeData
     },
     move(key: Key, toParentKey: Key | null, index: number) {
       setItems(({items, nodeMap: originalMap}) => {
+        let current = toParentKey;
+        while (current != null) {
+          if (current === key) {
+            throw new Error('Cannot move an item to be a child of itself.');
+          }
+          current = originalMap.get(current)?.parentKey ?? null;
+        }
+
         let node = originalMap.get(key);
         if (!node) {
           return {items, nodeMap: originalMap};
@@ -497,6 +505,9 @@ function moveItems<T extends object>(
     }
     parent = nodeMap.get(parent.parentKey!) ?? null;
   }
+  if (parent != null && removeKeys.has(parent.key)) {
+    throw new Error('Cannot move an item to be a child of itself.');
+  }
 
   let originalToIndex = toIndex;
 

packages/react-stately/test/data/useTreeData.test.js

@@ -903,7 +903,7 @@ describe('useTreeData', function () {
     expect(result.current.items[0].children[0].children.length).toEqual(3);
   });
 
-  describe('moveBefore error', function () {
+  describe('move errors', function () {
     const consoleError = console.error;
     beforeEach(() => {
       console.error = jest.fn();
@@ -913,15 +913,56 @@ describe('useTreeData', function () {
       console.error = consoleError;
     });
 
-    it('cannot move an item within itself', function () {
-      const initialItems = [...initial, {name: 'Emily'}, {name: 'Eli'}];
-
-      let {result} = renderHook(() => useTreeData({initialItems, getChildren, getKey}));
+    let expectToThrow = cb => {
+      let didThrow = false;
       try {
-        act(() => result.current.moveBefore('Suzie', ['John', 'Sam', 'Eli']));
+        cb();
       } catch (e) {
+        didThrow = true;
         expect(e.toString()).toContain('Cannot move an item to be a child of itself.');
       }
+
+      if (!didThrow) {
+        expect(console.error).toHaveBeenCalled();
+        const errorString = console.error.mock.calls.flat().join(' ');
+        expect(errorString).toContain('Cannot move an item to be a child of itself.');
+      }
+    };
+
+    it('cannot move an item before itself', function () {
+      const initialItems = [...initial, {name: 'Emily'}, {name: 'Eli'}];
+      let {result} = renderHook(() => useTreeData({initialItems, getChildren, getKey}));
+      expectToThrow(() => act(() => result.current.moveBefore('Suzie', ['John', 'Sam', 'Eli'])));
+    });
+
+    it('cannot move a root-level item before itself', function () {
+      const initialItems = [...initial, {name: 'Emily'}, {name: 'Eli'}];
+      let {result} = renderHook(() => useTreeData({initialItems, getChildren, getKey}));
+      expectToThrow(() => act(() => result.current.moveBefore('Suzie', ['David'])));
+    });
+
+    it('cannot move an item after itself', function () {
+      const initialItems = [...initial, {name: 'Emily'}, {name: 'Eli'}];
+      let {result} = renderHook(() => useTreeData({initialItems, getChildren, getKey}));
+      expectToThrow(() => act(() => result.current.moveAfter('Suzie', ['John'])));
+    });
+
+    it('cannot move a root-level item after itself', function () {
+      const initialItems = [...initial, {name: 'Emily'}, {name: 'Eli'}];
+      let {result} = renderHook(() => useTreeData({initialItems, getChildren, getKey}));
+      expectToThrow(() => act(() => result.current.moveAfter('Suzie', ['David'])));
+    });
+
+    it('cannot move an item into itself', function () {
+      const initialItems = [...initial, {name: 'Emily'}, {name: 'Eli'}];
+      let {result} = renderHook(() => useTreeData({initialItems, getChildren, getKey}));
+      expectToThrow(() => act(() => result.current.move('John', 'Suzie', 0)));
+    });
+
+    it('cannot move a root-level item into itself', function () {
+      const initialItems = [...initial, {name: 'Emily'}, {name: 'Eli'}];
+      let {result} = renderHook(() => useTreeData({initialItems, getChildren, getKey}));
+      expectToThrow(() => act(() => result.current.move('David', 'Suzie', 0)));
     });
   });