fix(editor): fix target element index when creating/adding elements to frames (#11257)

packages/element/src/Scene.ts

@@ -338,29 +338,20 @@ export class Scene {
     this.callbacks.clear();
   }
 
-  insertElementAtIndex(element: ExcalidrawElement, index: number) {
-    if (!Number.isFinite(index) || index < 0) {
-      throw new Error(
-        "insertElementAtIndex can only be called with index >= 0",
-      );
-    }
-
-    const nextElements = [
-      ...this.elements.slice(0, index),
-      element,
-      ...this.elements.slice(index),
-    ];
-
-    syncMovedIndices(nextElements, arrayToMap([element]));
-
-    this.replaceAllElements(nextElements);
-  }
-
-  insertElementsAtIndex(elements: ExcalidrawElement[], index: number) {
+  /** low-level - generally use app.insertNewElements() */
+  insertElementsAtIndex(
+    elements: ExcalidrawElement[],
+    /** null indicates end of the array */
+    index: number | null,
+  ) {
     if (!elements.length) {
       return;
     }
 
+    if (index === null) {
+      index = this.elements.length;
+    }
+
     if (!Number.isFinite(index) || index < 0) {
       throw new Error(
         "insertElementAtIndex can only be called with index >= 0",
@@ -378,24 +369,9 @@ export class Scene {
     this.replaceAllElements(nextElements);
   }
 
+  /** low-level - generally use app.insertNewElement() */
   insertElement = (element: ExcalidrawElement) => {
-    const index = element.frameId
-      ? this.getElementIndex(element.frameId)
-      : this.elements.length;
-
-    this.insertElementAtIndex(element, index);
-  };
-
-  insertElements = (elements: ExcalidrawElement[]) => {
-    if (!elements.length) {
-      return;
-    }
-
-    const index = elements[0]?.frameId
-      ? this.getElementIndex(elements[0].frameId)
-      : this.elements.length;
-
-    this.insertElementsAtIndex(elements, index);
+    this.insertElementsAtIndex([element], null);
   };
 
   getElementIndex(elementId: string) {

packages/element/src/collision.ts

@@ -61,6 +61,8 @@ import { distanceToElement } from "./distance";
 
 import { getBindingGap } from "./binding";
 
+import { hasBackground } from "./comparisons";
+
 import type {
   ElementsMap,
   ExcalidrawArrowElement,
@@ -83,7 +85,7 @@ export const shouldTestInside = (element: ExcalidrawElement) => {
   }
 
   const isDraggableFromInside =
-    !isTransparent(element.backgroundColor) ||
+    (hasBackground(element.type) && !isTransparent(element.backgroundColor)) ||
     hasBoundTextElement(element) ||
     isIframeLikeElement(element) ||
     isTextElement(element);
@@ -324,7 +326,10 @@ export const getAllHoveredElementAtPoint = (
     ) {
       candidateElements.push(element);
 
-      if (!isTransparent(element.backgroundColor)) {
+      if (
+        hasBackground(element.type) &&
+        !isTransparent(element.backgroundColor)
+      ) {
         break;
       }
     }

packages/element/src/duplicate.ts

@@ -111,6 +111,9 @@ export const duplicateElements = (
          * user interaction.
          */
         type: "everything";
+        // TODO remove/review this once we add frame children order migration
+        // and invariant checks
+        preserveFrameChildrenOrder?: boolean;
       }
     | {
         /**
@@ -170,6 +173,8 @@ export const duplicateElements = (
     opts.type === "in-place"
       ? opts.idsOfElementsToDuplicate
       : new Map(elements.map((el) => [el.id, el]));
+  const preserveFrameChildrenOrder =
+    opts.type === "everything" && opts.preserveFrameChildrenOrder;
 
   // For sanity
   if (opts.type === "in-place") {
@@ -277,7 +282,7 @@ export const duplicateElements = (
     if (groupId) {
       const groupElements = getElementsInGroup(elements, groupId).flatMap(
         (element) =>
-          isFrameLikeElement(element)
+          isFrameLikeElement(element) && !preserveFrameChildrenOrder
             ? [...getFrameChildren(elements, element.id), element]
             : [element],
       );
@@ -293,13 +298,25 @@ export const duplicateElements = (
     // frame duplication
     // -------------------------------------------------------------------------
 
-    if (element.frameId && frameIdsToDuplicate.has(element.frameId)) {
+    if (
+      !preserveFrameChildrenOrder &&
+      element.frameId &&
+      frameIdsToDuplicate.has(element.frameId)
+    ) {
       continue;
     }
 
     if (isFrameLikeElement(element)) {
       const frameId = element.id;
 
+      if (preserveFrameChildrenOrder) {
+        insertBeforeOrAfterIndex(
+          findLastIndex(elementsWithDuplicates, (el) => el.id === frameId),
+          copyElements(element),
+        );
+        continue;
+      }
+
       const frameChildren = getFrameChildren(elements, frameId);
 
       const targetIndex = findLastIndex(elementsWithDuplicates, (el) => {

packages/element/src/frame.ts

@@ -23,6 +23,7 @@ import {
 } from "./bounds";
 import { mutateElement } from "./mutateElement";
 import { getBoundTextElement, getContainerElement } from "./textElement";
+import { syncMovedIndices } from "./fractionalIndex";
 import {
   isFrameElement,
   isFrameLikeElement,
@@ -491,10 +492,44 @@ export const filterElementsEligibleAsFrameChildren = (
   return eligibleElements;
 };
 
+export const getCommonFrameId = (elements: readonly ExcalidrawElement[]) => {
+  let commonFrameId: ExcalidrawElement["frameId"] | undefined;
+
+  for (const element of elements) {
+    if (isFrameLikeElement(element) || !element.frameId) {
+      return null;
+    }
+
+    if (commonFrameId === undefined) {
+      commonFrameId = element.frameId;
+    } else if (commonFrameId !== element.frameId) {
+      return null;
+    }
+  }
+
+  return commonFrameId ?? null;
+};
+
+export const getFrameChildrenInsertionIndex = (
+  elements: readonly ExcalidrawElement[],
+  frameId: ExcalidrawFrameLikeElement["id"],
+): number | null => {
+  for (let index = elements.length - 1; index >= 0; index--) {
+    const element = elements[index];
+
+    if (element.id === frameId) {
+      return index;
+    } else if (element.frameId === frameId) {
+      return index + 1;
+    }
+  }
+
+  return null;
+};
+
 /**
- * Retains (or repairs for target frame) the ordering invriant where children
- * elements come right before the parent frame:
- * [el, el, child, child, frame, el]
+ * Adds elements and their bound elements to frame. Reorders added elements to
+ * be just below frame, or just above its highest child (whichever is higher).
  *
  * @returns mutated allElements (same data structure)
  */
@@ -502,19 +537,11 @@ export const addElementsToFrame = <T extends ElementsMapOrArray>(
   allElements: T,
   elementsToAdd: NonDeletedExcalidrawElement[],
   frame: ExcalidrawFrameLikeElement,
-  appState: AppState,
 ): T => {
   const elementsMap = arrayToMap(allElements);
-  const currTargetFrameChildrenMap = new Map<ExcalidrawElement["id"], true>();
-  for (const element of allElements.values()) {
-    if (element.frameId === frame.id) {
-      currTargetFrameChildrenMap.set(element.id, true);
-    }
-  }
+  const commonFrameId = getCommonFrameId(elementsToAdd);
 
-  const suppliedElementsToAddSet = new Set(elementsToAdd.map((el) => el.id));
-
-  const finalElementsToAdd: ExcalidrawElement[] = [];
+  const finalElementsToAdd = new Set<ExcalidrawElement>();
 
   const otherFrames = new Set<ExcalidrawFrameLikeElement["id"]>();
 
@@ -525,7 +552,8 @@ export const addElementsToFrame = <T extends ElementsMapOrArray>(
   }
 
   // - add bound text elements if not already in the array
-  // - filter out elements that are already in the frame
+  // - keep elements already in the frame so mixed selections can be reordered
+  //   together
   for (const element of omitGroupsContainingFrameLikes(
     allElements,
     elementsToAdd,
@@ -538,38 +566,68 @@ export const addElementsToFrame = <T extends ElementsMapOrArray>(
       continue;
     }
 
-    // if the element is already in another frame (which is also in elementsToAdd),
-    // it means that frame and children are selected at the same time
-    // => keep original frame membership, do not add to the target frame
-    if (
-      element.frameId &&
-      appState.selectedElementIds[element.id] &&
-      appState.selectedElementIds[element.frameId]
-    ) {
+    if (element.frameId && element.frameId !== frame.id) {
       continue;
     }
 
-    if (!currTargetFrameChildrenMap.has(element.id)) {
-      finalElementsToAdd.push(element);
-    }
+    finalElementsToAdd.add(element);
 
     const boundTextElement = getBoundTextElement(element, elementsMap);
-    if (
-      boundTextElement &&
-      !suppliedElementsToAddSet.has(boundTextElement.id) &&
-      !currTargetFrameChildrenMap.has(boundTextElement.id)
-    ) {
-      finalElementsToAdd.push(boundTextElement);
+    if (boundTextElement && !finalElementsToAdd.has(boundTextElement)) {
+      finalElementsToAdd.add(boundTextElement);
     }
   }
 
   for (const element of finalElementsToAdd) {
-    mutateElement(element, elementsMap, {
-      frameId: frame.id,
-    });
+    // we don't always need to update the element if it's already in the frame,
+    // but we still need to accumulate in finalElementsToAdd so we potentially
+    // reorder them if added together
+    if (element.frameId !== frame.id) {
+      mutateElement(element, elementsMap, {
+        frameId: frame.id,
+      });
+    }
   }
 
-  return allElements;
+  // (re)order elements to be just below the frame,
+  // or just above the highest child if that is higher
+  // (latter case is denormalized order until we migrate)
+  // ---------------------------------------------------------------------------
+
+  if (
+    !finalElementsToAdd.size ||
+    // if all elements to add already belong to the frame, then we don't want to
+    // reorder (case: we're dragging element children within the frame)
+    commonFrameId === frame.id
+  ) {
+    return allElements;
+  }
+
+  const otherElements = Array.from(allElements.values()).filter(
+    (element) => !finalElementsToAdd.has(element),
+  );
+  const insertionIndex = getFrameChildrenInsertionIndex(
+    otherElements,
+    frame.id,
+  );
+
+  if (insertionIndex === null) {
+    return allElements;
+  }
+
+  const reorderedElements = [
+    ...otherElements.slice(0, insertionIndex),
+    ...finalElementsToAdd,
+    ...otherElements.slice(insertionIndex),
+  ];
+
+  syncMovedIndices(reorderedElements, arrayToMap([...finalElementsToAdd]));
+
+  return (
+    Array.isArray(allElements)
+      ? reorderedElements
+      : new Map(reorderedElements.map((element) => [element.id, element]))
+  ) as T;
 };
 
 export const removeElementsFromFrame = (
@@ -623,13 +681,11 @@ export const replaceAllElementsInFrame = <T extends ExcalidrawElement>(
   allElements: readonly T[],
   nextElementsInFrame: ExcalidrawElement[],
   frame: ExcalidrawFrameLikeElement,
-  app: AppClassProperties,
 ): T[] => {
   return addElementsToFrame(
     removeAllElementsFromFrame(allElements, frame),
     nextElementsInFrame,
     frame,
-    app.state,
   ).slice();
 };
 

packages/element/src/typeChecks.ts

@@ -392,3 +392,23 @@ export const canBecomePolygon = (
     (points.length === 3 && !pointsEqual(points[0], points[points.length - 1]))
   );
 };
+
+export const isEligibleFrameChildType = (type: ElementOrToolType) => {
+  switch (type) {
+    case "rectangle":
+    case "diamond":
+    case "ellipse":
+    case "arrow":
+    case "line":
+    case "freedraw":
+    case "text":
+    case "image":
+    case "frame":
+    case "embeddable": {
+      return true;
+    }
+    default: {
+      return false;
+    }
+  }
+};

packages/element/tests/frame.test.tsx

@@ -5,12 +5,15 @@ import {
 import { arrayToMap } from "@excalidraw/common";
 
 import { API } from "@excalidraw/excalidraw/tests/helpers/api";
-import { Keyboard, Pointer } from "@excalidraw/excalidraw/tests/helpers/ui";
+import { Keyboard, Pointer, UI } from "@excalidraw/excalidraw/tests/helpers/ui";
+import { getTextEditor } from "@excalidraw/excalidraw/tests/queries/dom";
 import {
   getCloneByOrigId,
   render,
 } from "@excalidraw/excalidraw/tests/test-utils";
 
+import { getSelectedElements } from "@excalidraw/excalidraw/scene";
+
 import { elementOverlapsWithFrame } from "../src/frame";
 
 import type {
@@ -151,6 +154,230 @@ describe("adding elements to frames", () => {
     ).toBe(true);
   });
 
+  it("should not add a newly created element to a frame behind a non-frame element", () => {
+    const cover = API.createElement({
+      id: "cover",
+      type: "rectangle",
+      x: 10,
+      y: 10,
+      width: 80,
+      height: 80,
+      backgroundColor: "#ffc9c9",
+    });
+
+    API.setElements([frame, cover]);
+
+    UI.clickTool("rectangle");
+    mouse.downAt(20, 20);
+    mouse.moveTo(40, 40);
+    mouse.upAt(40, 40);
+
+    const createdElement = h.elements.find(
+      (element) => element.id !== frame.id && element.id !== cover.id,
+    );
+
+    expect(createdElement?.frameId).toBe(null);
+    expect(h.elements.map((element) => element.id)).toEqual([
+      frame.id,
+      cover.id,
+      createdElement?.id,
+    ]);
+  });
+
+  it("should add a newly created element to a frame over a non-frame element", () => {
+    const cover = API.createElement({
+      id: "cover",
+      type: "rectangle",
+      x: 10,
+      y: 10,
+      width: 80,
+      height: 80,
+      backgroundColor: "#ffc9c9",
+    });
+
+    API.setElements([cover, frame]);
+
+    UI.clickTool("rectangle");
+    mouse.downAt(20, 20);
+    mouse.moveTo(40, 40);
+    mouse.upAt(40, 40);
+
+    const createdElement = h.elements.find(
+      (element) => element.id !== frame.id && element.id !== cover.id,
+    );
+
+    expect(createdElement?.frameId).toBe(frame.id);
+  });
+
+  it("should highlight the target frame while creating a new element", () => {
+    API.setElements([frame]);
+
+    UI.clickTool("rectangle");
+    mouse.downAt(20, 20);
+    mouse.moveTo(40, 40);
+
+    expect(h.state.frameToHighlight?.id).toBe(frame.id);
+
+    mouse.upAt(40, 40);
+
+    expect(h.state.frameToHighlight).toBe(null);
+  });
+
+  it("should highlight the target frame while hovering with a creation tool", () => {
+    API.setElements([frame]);
+
+    UI.clickTool("rectangle");
+    mouse.moveTo(20, 20);
+
+    expect(h.state.frameToHighlight?.id).toBe(frame.id);
+
+    mouse.moveTo(200, 200);
+
+    expect(h.state.frameToHighlight).toBe(null);
+  });
+
+  it("should not add grid-snapped text outside the frame to the clicked frame", async () => {
+    const offsetFrame = API.createElement({
+      id: "offsetFrame",
+      type: "frame",
+      x: 10,
+      y: 0,
+      width: 150,
+      height: 150,
+    });
+
+    API.setElements([offsetFrame]);
+    API.setAppState({
+      gridModeEnabled: true,
+    });
+
+    UI.clickTool("text");
+    mouse.clickAt(12, 0);
+
+    await getTextEditor();
+
+    const createdText = h.elements.find(
+      (element) => element.id !== offsetFrame.id,
+    );
+
+    expect(createdText?.x).toBe(0);
+    expect(createdText?.y).toBe(0);
+    expect(createdText?.frameId).toBe(null);
+  });
+
+  it("should add a newly created element to a frame behind another frame", () => {
+    const lockedFrame = API.createElement({
+      id: "lockedFrame",
+      type: "frame",
+      x: 10,
+      y: 10,
+      width: 80,
+      height: 80,
+      locked: true,
+    });
+
+    API.setElements([frame, lockedFrame]);
+
+    UI.clickTool("rectangle");
+    mouse.downAt(20, 20);
+    mouse.moveTo(40, 40);
+    mouse.upAt(40, 40);
+
+    const createdElement = h.elements.find(
+      (element) => element.id !== frame.id && element.id !== lockedFrame.id,
+    );
+
+    expect(createdElement?.frameId).toBe(frame.id);
+  });
+
+  it("should insert a newly created frame child just below its frame", () => {
+    const frameChildUnderCursor = API.createElement({
+      id: "frameChildUnderCursor",
+      type: "rectangle",
+      x: 10,
+      y: 10,
+      width: 80,
+      height: 80,
+      backgroundColor: "#ffc9c9",
+      frameId: frame.id,
+    });
+    const otherFrameChild = API.createElement({
+      id: "otherFrameChild",
+      type: "rectangle",
+      x: 100,
+      y: 20,
+      width: 20,
+      height: 20,
+      frameId: frame.id,
+    });
+
+    API.setElements([frameChildUnderCursor, otherFrameChild, frame]);
+
+    UI.clickTool("rectangle");
+    mouse.downAt(20, 20);
+    mouse.moveTo(40, 40);
+    mouse.upAt(40, 40);
+
+    const createdElement = h.elements.find(
+      (element) =>
+        element.id !== frame.id &&
+        element.id !== frameChildUnderCursor.id &&
+        element.id !== otherFrameChild.id,
+    );
+
+    expect(createdElement?.frameId).toBe(frame.id);
+    expect(h.elements.map((element) => element.id)).toEqual([
+      frameChildUnderCursor.id,
+      otherFrameChild.id,
+      createdElement?.id,
+      frame.id,
+    ]);
+  });
+
+  it("should insert a newly created frame child above the highest frame child", () => {
+    const frameChildUnderCursor = API.createElement({
+      id: "frameChildUnderCursor",
+      type: "rectangle",
+      x: 10,
+      y: 10,
+      width: 80,
+      height: 80,
+      backgroundColor: "#ffc9c9",
+      frameId: frame.id,
+    });
+    const otherFrameChild = API.createElement({
+      id: "otherFrameChild",
+      type: "rectangle",
+      x: 100,
+      y: 20,
+      width: 20,
+      height: 20,
+      frameId: frame.id,
+    });
+
+    API.setElements([frame, frameChildUnderCursor, otherFrameChild]);
+
+    UI.clickTool("rectangle");
+    mouse.downAt(20, 20);
+    mouse.moveTo(40, 40);
+    mouse.upAt(40, 40);
+
+    const createdElement = h.elements.find(
+      (element) =>
+        element.id !== frame.id &&
+        element.id !== frameChildUnderCursor.id &&
+        element.id !== otherFrameChild.id,
+    );
+
+    expect(createdElement?.frameId).toBe(frame.id);
+    expect(h.elements.map((element) => element.id)).toEqual([
+      frame.id,
+      frameChildUnderCursor.id,
+      otherFrameChild.id,
+      createdElement?.id,
+    ]);
+  });
+
   const commonTestCases = async (
     func: typeof resizeFrameOverElement | typeof dragElementIntoFrame,
   ) => {
@@ -457,6 +684,329 @@ describe("adding elements to frames", () => {
       expect(API.getElement(containingRect).frameId).toBe(frame.id);
     });
 
+    it("should drag an element into a frame", () => {
+      API.setElements([rect2, frame]);
+
+      dragElementIntoFrame(frame, rect2);
+
+      expect(rect2.frameId).toBe(frame.id);
+    });
+
+    it("should layer a dragged element above the highest frame child", () => {
+      const frameChild = API.createElement({
+        id: "frameChild",
+        type: "rectangle",
+        x: 10,
+        y: 10,
+        width: 20,
+        height: 20,
+        frameId: frame.id,
+      });
+
+      API.setElements([frame, frameChild, rect2]);
+
+      dragElementIntoFrame(frame, rect2);
+
+      expect(rect2.frameId).toBe(frame.id);
+      expect(h.elements.map((element) => element.id)).toEqual([
+        frame.id,
+        frameChild.id,
+        rect2.id,
+      ]);
+      expect(rect2.index! > frameChild.index!).toBe(true);
+      expect(rect2.index! > frame.index!).toBe(true);
+    });
+
+    it("should preview a dragged element above the highest frame child before pointerup", () => {
+      const frameChild = API.createElement({
+        id: "frameChild",
+        type: "rectangle",
+        x: 10,
+        y: 10,
+        width: 20,
+        height: 20,
+        frameId: frame.id,
+      });
+
+      API.setElements([rect2, frame, frameChild]);
+      API.setSelectedElements([rect2]);
+      API.updateElement(rect2, {
+        x: 10,
+        y: 10,
+      });
+
+      const getRenderableElementIds = (
+        selectedElementsAreBeingDragged: boolean,
+      ) => {
+        return h.app.renderer
+          .getRenderableElements({
+            zoom: h.state.zoom,
+            offsetLeft: 0,
+            offsetTop: 0,
+            scrollX: 0,
+            scrollY: 0,
+            height: 1000,
+            width: 1000,
+            editingTextElement: h.state.editingTextElement,
+            newElement: h.state.newElement,
+            selectedElements: getSelectedElements(h.elements, h.state),
+            selectedElementsAreBeingDragged,
+            frameToHighlight: frame as ExcalidrawFrameLikeElement,
+          })
+          .visibleElements.map((element) => element.id);
+      };
+
+      expect(h.elements.map((element) => element.id)).toEqual([
+        rect2.id,
+        frame.id,
+        frameChild.id,
+      ]);
+      expect(getRenderableElementIds(false)).toEqual([
+        rect2.id,
+        frame.id,
+        frameChild.id,
+      ]);
+      expect(getRenderableElementIds(true)).toEqual([
+        frame.id,
+        frameChild.id,
+        rect2.id,
+      ]);
+      expect(h.elements.map((element) => element.id)).toEqual([
+        rect2.id,
+        frame.id,
+        frameChild.id,
+      ]);
+      expect(rect2.frameId).toBe(null);
+    });
+
+    it("should not preview reorder dragged elements already in the highlighted frame", () => {
+      const frameChild = API.createElement({
+        id: "frameChild",
+        type: "rectangle",
+        x: 10,
+        y: 10,
+        width: 20,
+        height: 20,
+        frameId: frame.id,
+      });
+      const otherFrameChild = API.createElement({
+        id: "otherFrameChild",
+        type: "rectangle",
+        x: 40,
+        y: 10,
+        width: 20,
+        height: 20,
+        frameId: frame.id,
+      });
+
+      API.setElements([frameChild, frame, otherFrameChild]);
+      API.setSelectedElements([frameChild]);
+
+      const renderableElementIds = h.app.renderer
+        .getRenderableElements({
+          zoom: h.state.zoom,
+          offsetLeft: 0,
+          offsetTop: 0,
+          scrollX: 0,
+          scrollY: 0,
+          height: 1000,
+          width: 1000,
+          editingTextElement: h.state.editingTextElement,
+          newElement: h.state.newElement,
+          selectedElements: getSelectedElements(h.elements, h.state),
+          selectedElementsAreBeingDragged: true,
+          frameToHighlight: frame as ExcalidrawFrameLikeElement,
+        })
+        .visibleElements.map((element) => element.id);
+
+      expect(renderableElementIds).toEqual([
+        frameChild.id,
+        frame.id,
+        otherFrameChild.id,
+      ]);
+    });
+
+    it("should put a dragged mixed selection above the highest frame child", () => {
+      const frameChild = API.createElement({
+        id: "frameChild",
+        type: "rectangle",
+        x: 50,
+        y: 10,
+        width: 20,
+        height: 20,
+        frameId: frame.id,
+        boundElements: [{ id: "boundText", type: "text" }],
+      });
+      const boundText = API.createElement({
+        id: "boundText",
+        type: "text",
+        x: 50,
+        y: 10,
+        width: 20,
+        height: 20,
+        containerId: frameChild.id,
+        frameId: frame.id,
+      });
+      const otherFrameChild = API.createElement({
+        id: "otherFrameChild",
+        type: "rectangle",
+        x: 80,
+        y: 10,
+        width: 20,
+        height: 20,
+        frameId: frame.id,
+      });
+      const nonFrameElement = API.createElement({
+        id: "nonFrameElement",
+        type: "rectangle",
+        x: 155,
+        y: 10,
+        width: 20,
+        height: 20,
+      });
+
+      API.setElements([
+        frame,
+        frameChild,
+        boundText,
+        otherFrameChild,
+        nonFrameElement,
+      ]);
+      API.setSelectedElements([frameChild, nonFrameElement]);
+
+      mouse.downAt(
+        nonFrameElement.x + nonFrameElement.width / 2,
+        nonFrameElement.y + nonFrameElement.height / 2,
+      );
+      mouse.moveTo(frame.x + frame.width - 5, nonFrameElement.y + 10);
+      mouse.up();
+
+      expect(frameChild.frameId).toBe(frame.id);
+      expect(boundText.frameId).toBe(frame.id);
+      expect(nonFrameElement.frameId).toBe(frame.id);
+      expect(h.elements.map((element) => element.id)).toEqual([
+        frame.id,
+        otherFrameChild.id,
+        frameChild.id,
+        boundText.id,
+        nonFrameElement.id,
+      ]);
+    });
+
+    it("should not reorder dragged elements already in the highlighted frame", () => {
+      const frameChild = API.createElement({
+        id: "frameChild",
+        type: "rectangle",
+        x: 50,
+        y: 10,
+        width: 20,
+        height: 20,
+        frameId: frame.id,
+      });
+      const otherFrameChild = API.createElement({
+        id: "otherFrameChild",
+        type: "rectangle",
+        x: 80,
+        y: 10,
+        width: 20,
+        height: 20,
+        frameId: frame.id,
+      });
+
+      API.setElements([frame, frameChild, otherFrameChild]);
+      API.setSelectedElements([frameChild]);
+
+      mouse.downAt(
+        frameChild.x + frameChild.width / 2,
+        frameChild.y + frameChild.height / 2,
+      );
+      mouse.moveTo(frameChild.x + frameChild.width / 2 + 5, frameChild.y + 10);
+      mouse.up();
+
+      expect(frameChild.frameId).toBe(frame.id);
+      expect(h.elements.map((element) => element.id)).toEqual([
+        frame.id,
+        frameChild.id,
+        otherFrameChild.id,
+      ]);
+    });
+
+    it("should not drag an element into a frame behind a non-frame element", () => {
+      const cover = API.createElement({
+        id: "cover",
+        type: "rectangle",
+        x: 10,
+        y: 10,
+        width: 80,
+        height: 80,
+        backgroundColor: "#ffc9c9",
+      });
+      API.setElements([frame, cover, rect2]);
+
+      mouse.clickAt(rect2.x, rect2.y);
+      mouse.downAt(rect2.x + rect2.width / 2, rect2.y + rect2.height / 2);
+      mouse.moveTo(20, 20);
+      mouse.upAt(20, 20);
+
+      expect(rect2.frameId).toBe(null);
+    });
+
+    it("should drag an element into a frame over a non-frame element", () => {
+      const cover = API.createElement({
+        id: "cover",
+        type: "rectangle",
+        x: 10,
+        y: 10,
+        width: 80,
+        height: 80,
+        backgroundColor: "#ffc9c9",
+      });
+      API.setElements([cover, rect2, frame]);
+
+      mouse.clickAt(rect2.x, rect2.y);
+      mouse.downAt(rect2.x + rect2.width / 2, rect2.y + rect2.height / 2);
+      mouse.moveTo(20, 20);
+      mouse.upAt(20, 20);
+
+      expect(rect2.frameId).toBe(frame.id);
+    });
+
+    it("should keep dragging a frame child over a non-frame element above its frame", () => {
+      const cover = API.createElement({
+        id: "cover",
+        type: "rectangle",
+        x: 10,
+        y: 10,
+        width: 80,
+        height: 80,
+        backgroundColor: "#ffc9c9",
+      });
+      const frameChild = API.createElement({
+        id: "frameChild",
+        type: "rectangle",
+        x: 100,
+        y: 20,
+        width: 20,
+        height: 20,
+        frameId: frame.id,
+      });
+
+      API.setElements([frameChild, frame, cover]);
+      API.setSelectedElements([frameChild]);
+
+      mouse.downAt(
+        frameChild.x + frameChild.width / 2,
+        frameChild.y + frameChild.height / 2,
+      );
+      mouse.moveTo(20, 20);
+
+      expect(h.state.frameToHighlight?.id).toBe(frame.id);
+
+      mouse.upAt(20, 20);
+
+      expect(frameChild.frameId).toBe(frame.id);
+    });
+
     it.skip("should drag element inside, duplicate it and keep it in frame", () => {
       API.setElements([frame, rect2]);