fix(nav): Back finds an item that moved to another list by its name

2026-10-28 21:54:00 +01:00
parent 0469812499
commit c86ec7f7a5
2 changed files with 99 additions and 12 deletions
@@ -0,0 +1,75 @@
+// @vitest-environment jsdom
+//
+// Back to a page whose item changed lists while it was away. The notification center holds a row
+// that asked for the reader in "Needs you" for the visit; on the next visit the same row, read now,
+// sits in the stream below. The restore matched the unnamed list by its place, missed the name there
+// and fell back to the saved index — the focus landed on the neighbour, and Enter opened the wrong
+// notification. Its own file: listNav keeps module-level state.
+import { afterEach, describe, expect, it } from "vitest";
+import { act, cleanup, render } from "@testing-library/react";
+import { useRef } from "react";
+
+import { navItemAttrs, navPosition, restoreNavPosition, useListNav } from "./listNav";
+
+afterEach(cleanup);
+
+function List({ items }: { items: string[] }) {
+  const ref = useRef<HTMLDivElement>(null);
+  useListNav(ref, { enabled: true });
+  return (
+    <div ref={ref}>
+      {items.map((t, i) => (
+        <div key={`${t}-${i}`} {...navItemAttrs(i, t)}>
+          <button data-nav-open="">{t}</button>
+        </div>
+      ))}
+    </div>
+  );
+}
+
+const Page = ({ lists }: { lists: string[][] }) => (
+  <main>
+    {lists.map((items, i) => (
+      <List key={i} items={items} />
+    ))}
+  </main>
+);
+
+const button = (name: string) =>
+  [...document.querySelectorAll("button")].find((b) => b.textContent === name)!;
+const focused = () => document.activeElement?.closest("[data-nav-index]")?.textContent;
+const wait = (ms: number) => act(() => new Promise((r) => setTimeout(r, ms)));
+
+async function leaveAndReturn(before: string[][], from: string, after: string[][]) {
+  const { unmount } = render(<Page lists={before} />);
+  button(from).focus();
+  const pos = navPosition()!;
+  unmount(); // the page switch
+  render(<Page lists={after} />); // Back
+  const cancel = restoreNavPosition(pos);
+  await wait(120);
+  cancel();
+}
+
+describe("Back to an item that moved to another list", () => {
+  it("finds it by its name in the list it moved to, not its neighbour at the old place", async () => {
+    await leaveAndReturn([["subscribed", "download"], ["older"]], "subscribed", [
+      ["download"],
+      ["subscribed", "older"],
+    ]);
+    expect(focused()).toBe("subscribed");
+  });
+
+  it("finds it when the list it left is gone altogether", async () => {
+    await leaveAndReturn([["subscribed"], ["older"]], "subscribed", [["subscribed", "older"]]);
+    expect(focused()).toBe("subscribed");
+  });
+
+  it("does not guess between two items of that name elsewhere: the saved place", async () => {
+    await leaveAndReturn([["twin", "download"], ["older"]], "twin", [
+      ["download"],
+      ["twin", "older", "twin"],
+    ]);
+    expect(focused()).toBe("download");
+  });
+});