fix(studio): make sdk cutover transactional (#2155)

packages/studio/src/hooks/usePersistentEditHistory.projectOwnership.test.tsx

@@ -0,0 +1,60 @@
+// @vitest-environment happy-dom
+import { act } from "react";
+import { createRoot } from "react-dom/client";
+import { describe, expect, it } from "vitest";
+import { createMemoryEditHistoryStorage } from "../utils/editHistoryStorage";
+import { usePersistentEditHistory } from "./usePersistentEditHistory";
+
+(globalThis as unknown as { IS_REACT_ACT_ENVIRONMENT: boolean }).IS_REACT_ACT_ENVIRONMENT = true;
+
+async function flushAsyncEffects(): Promise<void> {
+  await act(async () => {
+    await new Promise((resolve) => setTimeout(resolve, 0));
+  });
+}
+
+describe("usePersistentEditHistory project ownership", () => {
+  it("rejects a delayed project A recorder after project B becomes active", async () => {
+    const storage = createMemoryEditHistoryStorage();
+    const now = () => 100;
+    const captured: { history: ReturnType<typeof usePersistentEditHistory> | null } = {
+      history: null,
+    };
+
+    function Probe({ projectId }: { projectId: string }) {
+      captured.history = usePersistentEditHistory({ projectId, storage, now });
+      return null;
+    }
+
+    const root = createRoot(document.createElement("div"));
+    await act(async () => root.render(<Probe projectId="project-a" />));
+    await flushAsyncEffects();
+    const recordProjectA = captured.history?.recordEdit;
+    if (!recordProjectA) throw new Error("project A history did not load");
+
+    await act(async () => root.render(<Probe projectId="project-b" />));
+    await expect(
+      recordProjectA({
+        label: "Delayed A edit",
+        kind: "manual",
+        files: { "index.html": { before: "A", after: "A2" } },
+      }),
+    ).rejects.toThrow("inactive project project-a");
+    await flushAsyncEffects();
+
+    const recordProjectB = captured.history?.recordEdit;
+    if (!recordProjectB) throw new Error("project B history did not load");
+    await act(async () => {
+      await recordProjectB({
+        label: "B edit",
+        kind: "manual",
+        files: { "index.html": { before: "B", after: "B2" } },
+      });
+    });
+
+    expect(await storage.get("project-a")).toBeNull();
+    expect((await storage.get("project-b"))?.undo.map((entry) => entry.label)).toEqual(["B edit"]);
+
+    await act(async () => root.unmount());
+  });
+});