switch versions e2e (#312)

e2e-tests/switch_versions.spec.ts

@@ -0,0 +1,22 @@
+import { test } from "./helpers/test_helper";
+import { expect } from "@playwright/test";
+
+test("switch versions", async ({ po }) => {
+  await po.setUp({ autoApprove: true });
+  await po.sendPrompt("tc=write-index");
+
+  await po.snapshotPreview();
+
+  expect(
+    await po.page.getByRole("button", { name: "Version" }).textContent(),
+  ).toBe("Version 2");
+  await po.page.getByRole("button", { name: "Version" }).click();
+  await po.page.getByText("Init Dyad app Undo").click();
+  await po.snapshotPreview();
+
+  await po.page.getByRole("button", { name: "Undo to latest version" }).click();
+  // Should be same as the previous snapshot, but just to be sure.
+  await po.snapshotPreview();
+
+  await expect(po.page.getByText("Version 3")).toBeVisible();
+});