ok

tests/player-state.test.mjs

@@ -0,0 +1,87 @@
+import assert from "node:assert/strict";
+import { test } from "node:test";
+import { PlayerStateClient } from "../public/player-state.js";
+
+test("polls reuse tracks and accept edits from another browser", async () => {
+  const tracks = [{ title: "First" }];
+  const changedTracks = [{ title: "Second" }];
+  const responses = [
+    { playlistVersion: "first", tracks, position: 0 },
+    { playlistVersion: "first", tracks: null, position: 1 },
+    { playlistVersion: "changed", tracks: changedTracks, position: 2 },
+    { playlistVersion: "changed", tracks: null, position: 3 },
+  ];
+  const paths = [];
+  const client = new PlayerStateClient(async (path) => {
+    paths.push(path);
+    return responses.shift();
+  });
+  assert.equal((await client.request("/api/state")).tracks, tracks);
+  const unchanged = await client.request("/api/state");
+  assert.equal(unchanged.tracks, tracks);
+  assert.equal(unchanged.position, 1);
+  assert.equal((await client.request("/api/state")).tracks, changedTracks);
+  assert.equal((await client.request("/api/state")).tracks, changedTracks);
+  assert.deepEqual(paths, [
+    "/api/state", "/api/state?playlistVersion=first",
+    "/api/state?playlistVersion=first", "/api/state?playlistVersion=changed",
+  ]);
+});
+
+test("commands and discovery wait for polling and use its latest version", async () => {
+  let finishPoll;
+  const paths = [];
+  const commandBody = { index: 1 };
+  const client = new PlayerStateClient((path, body) => {
+    paths.push(path);
+    if (paths.length === 1) {
+      return new Promise((resolve) => { finishPoll = resolve; });
+    }
+    if (paths.length === 2) {
+      assert.equal(body, commandBody);
+      return { playlistVersion: "other-tab", tracks: [] };
+    }
+    return { playlistVersion: "other-tab", tracks: null };
+  });
+  const poll = client.request("/api/state");
+  const command = client.request("/api/command/tab-select", commandBody);
+  const discovery = client.request("/api/discover", {});
+  await Promise.resolve();
+  assert.deepEqual(paths, ["/api/state"]);
+  finishPoll({ playlistVersion: "original-tab", tracks: [{ title: "First" }] });
+  await poll;
+  assert.deepEqual((await command).tracks, []);
+  assert.deepEqual((await discovery).tracks, []);
+  assert.deepEqual(paths, [
+    "/api/state",
+    "/api/command/tab-select?playlistVersion=original-tab",
+    "/api/discover?playlistVersion=other-tab",
+  ]);
+});
+
+test("a failed request leaves the queue usable", async () => {
+  let calls = 0;
+  const client = new PlayerStateClient(async () => {
+    if (++calls === 1) throw new Error("Offline");
+    return { playlistVersion: "recovered", tracks: [] };
+  });
+  await assert.rejects(client.request("/api/state"), /Offline/);
+  assert.deepEqual((await client.request("/api/state")).tracks, []);
+});
+
+test("mismatched omitted tracks force a full refresh instead of stale reuse", async () => {
+  const paths = [];
+  const responses = [
+    { playlistVersion: "before", tracks: [{ title: "Before" }] },
+    { playlistVersion: "after", tracks: null },
+    { playlistVersion: "after", tracks: [] },
+  ];
+  const client = new PlayerStateClient(async (path) => {
+    paths.push(path);
+    return responses.shift();
+  });
+  await client.request("/api/state");
+  await assert.rejects(client.request("/api/state"), /Playlist cache/);
+  assert.deepEqual((await client.request("/api/state")).tracks, []);
+  assert.equal(paths[2], "/api/state");
+});