1 files changed, 58 insertions, 0 deletions
diff --git a/web/test/tab-persistence.test.mjs b/web/test/tab-persistence.test.mjs
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+++ b/web/test/tab-persistence.test.mjs
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+// tab-persistence.test.mjs — TDD tests for main-tab localStorage persistence
+//
+// Run with: node --test web/test/tab-persistence.test.mjs
+
+import { describe, it, beforeEach } from 'node:test';
+import assert from 'node:assert/strict';
+
+// ── localStorage mock ──────────────────────────────────────────────────────────
+// Must be set up before importing app.js so the module sees the global.
+const store = new Map();
+globalThis.localStorage = {
+  getItem:    (k)    => store.has(k) ? store.get(k) : null,
+  setItem:    (k, v) => store.set(k, String(v)),
+  removeItem: (k)    => store.delete(k),
+  clear:      ()     => store.clear(),
+};
+
+import { getActiveMainTab, setActiveMainTab } from '../app.js';
+
+describe('getActiveMainTab', () => {
+  beforeEach(() => store.clear());
+
+  it('returns "queue" when localStorage has no stored value', () => {
+    assert.equal(getActiveMainTab(), 'queue');
+  });
+
+  it('returns the tab name stored by setActiveMainTab', () => {
+    setActiveMainTab('settings');
+    assert.equal(getActiveMainTab(), 'settings');
+  });
+
+  it('returns "queue" after localStorage value is removed', () => {
+    setActiveMainTab('stats');
+    localStorage.removeItem('activeMainTab');
+    assert.equal(getActiveMainTab(), 'queue');
+  });
+
+  it('reflects the most recent setActiveMainTab call', () => {
+    setActiveMainTab('stats');
+    setActiveMainTab('running');
+    assert.equal(getActiveMainTab(), 'running');
+  });
+});
+
+describe('setActiveMainTab', () => {
+  beforeEach(() => store.clear());
+
+  it('writes the tab name to localStorage under key "activeMainTab"', () => {
+    setActiveMainTab('drops');
+    assert.equal(localStorage.getItem('activeMainTab'), 'drops');
+  });
+
+  it('overwrites a previously stored tab', () => {
+    setActiveMainTab('queue');
+    setActiveMainTab('interrupted');
+    assert.equal(localStorage.getItem('activeMainTab'), 'interrupted');
+  });
+});