fix: missing session fields

packages/frontend/track/src/__tests__/tracker.spec.ts

@@ -0,0 +1,84 @@
+/**
+ * @vitest-environment happy-dom
+ */
+import { beforeEach, describe, expect, test, vi } from 'vitest';
+
+const sendTelemetryEvent = vi.fn().mockResolvedValue({ queued: true });
+const setTelemetryContext = vi.fn();
+
+vi.mock('../telemetry', () => ({
+  sendTelemetryEvent,
+  setTelemetryContext,
+}));
+
+const buildConfig = {
+  appVersion: '0.0.0',
+  appBuildType: 'stable',
+  editorVersion: '0.0.0',
+  isElectron: false,
+  isMobileEdition: false,
+  distribution: 'test',
+};
+
+beforeEach(() => {
+  (globalThis as any).BUILD_CONFIG = buildConfig;
+  localStorage.clear();
+  sessionStorage.clear();
+  sendTelemetryEvent.mockClear();
+  setTelemetryContext.mockClear();
+  vi.useRealTimers();
+  vi.resetModules();
+});
+
+async function loadTracker() {
+  return await import('../tracker');
+}
+
+describe('tracker session signals', () => {
+  test('sends first_visit and session_start on first event', async () => {
+    const { tracker } = await loadTracker();
+
+    tracker.track('test_event');
+
+    const events = sendTelemetryEvent.mock.calls.map(call => call[0]);
+    expect(events.map(event => event.eventName)).toEqual([
+      'first_visit',
+      'session_start',
+      'test_event',
+    ]);
+
+    const firstVisit = events[0];
+    expect(typeof (firstVisit.params as any).session_id).toBe('number');
+    expect((firstVisit.params as any).session_number).toBe(1);
+    expect((firstVisit.params as any).engagement_time_msec).toBe(1);
+  });
+
+  test('does not repeat first_visit for later events', async () => {
+    const { tracker } = await loadTracker();
+
+    tracker.track('event_a');
+    tracker.track('event_b');
+
+    const names = sendTelemetryEvent.mock.calls.map(call => call[0].eventName);
+    expect(names.filter(name => name === 'first_visit')).toHaveLength(1);
+    expect(names.filter(name => name === 'session_start')).toHaveLength(1);
+  });
+
+  test('increments session_number after idle timeout', async () => {
+    vi.useFakeTimers();
+    vi.setSystemTime(new Date('2024-01-01T00:00:00Z'));
+    const { tracker } = await loadTracker();
+
+    tracker.track('event_a');
+    sendTelemetryEvent.mockClear();
+
+    vi.setSystemTime(new Date('2024-01-01T01:00:00Z'));
+    tracker.track('event_b');
+
+    const events = sendTelemetryEvent.mock.calls.map(call => call[0]);
+    const sessionStart = events.find(
+      event => event.eventName === 'session_start'
+    );
+    expect((sessionStart?.params as any).session_number).toBe(2);
+  });
+});