test(quota-monitor): add timezone boundary coverage

services/github/quota-monitor.timezone-boundaries.test.ts

@@ -0,0 +1,69 @@
+import { beforeEach, describe, expect, it } from 'vitest';
+import quotaMonitor from './quota-monitor';
+
+describe('QuotaMonitor Timezone Boundaries', () => {
+  beforeEach(() => {
+    quotaMonitor.reset();
+  });
+
+  it('stores UTC midnight reset timestamps correctly', () => {
+    const utcMidnight = 1704067200; // 2024-01-01T00:00:00Z
+
+    quotaMonitor.updateQuotaFromHeaders({
+      'x-ratelimit-reset': String(utcMidnight),
+    });
+
+    expect(quotaMonitor.getQuota().resetTime).toBe(1704067200000);
+  });
+
+  it('preserves reset timestamps near EST calendar boundaries', () => {
+    const estBoundary = 1704085199;
+
+    quotaMonitor.updateQuotaFromHeaders({
+      'x-ratelimit-reset': String(estBoundary),
+    });
+
+    expect(quotaMonitor.getQuota().resetTime).toBe(estBoundary * 1000);
+  });
+
+  it('updates correctly when moving between IST and JST boundary timestamps', () => {
+    const istBoundary = 1704047400;
+    const jstBoundary = 1704034800;
+
+    quotaMonitor.updateQuotaFromHeaders({
+      'x-ratelimit-reset': String(istBoundary),
+    });
+
+    expect(quotaMonitor.getQuota().resetTime).toBe(istBoundary * 1000);
+
+    quotaMonitor.updateQuotaFromHeaders({
+      'x-ratelimit-reset': String(jstBoundary),
+    });
+
+    expect(quotaMonitor.getQuota().resetTime).toBe(jstBoundary * 1000);
+  });
+
+  it('handles leap year reset dates without losing precision', () => {
+    const leapYearReset = Math.floor(new Date('2024-02-29T00:00:00Z').getTime() / 1000);
+
+    quotaMonitor.updateQuotaFromHeaders({
+      'x-ratelimit-reset': String(leapYearReset),
+    });
+
+    expect(quotaMonitor.getQuota().resetTime).toBe(leapYearReset * 1000);
+  });
+
+  it('tracks DST transition timestamps while preserving quota state', () => {
+    quotaMonitor.updateQuotaFromHeaders({
+      'x-ratelimit-limit': '5000',
+      'x-ratelimit-remaining': '4500',
+      'x-ratelimit-reset': '1710054000',
+    });
+
+    const quota = quotaMonitor.getQuota();
+
+    expect(quota.limit).toBe(5000);
+    expect(quota.remaining).toBe(4500);
+    expect(quota.resetTime).toBe(1710054000000);
+  });
+});