date-utils.test.ts•7.34 kB
import {
getUTCDateKey,
getLocalDateKey,
getTodayUTCDateKey,
getTodayLocalDateKey,
formatDateName,
isSameUTCDay,
safeParseDate,
isValidUTCDateKey
} from '../utils/date-utils';
describe('Date Utils', () => {
describe('getUTCDateKey', () => {
it('should extract UTC date string in YYYY-MM-DD format', () => {
const date = new Date('2025-08-26T14:30:00.000Z');
expect(getUTCDateKey(date)).toBe('2025-08-26');
});
it('should handle timezone edge cases consistently', () => {
// Near midnight in different timezones should still give UTC date
const nearMidnightUTC = new Date('2025-08-26T00:01:00.000Z');
const lateNightLocal = new Date('2025-08-25T23:59:00-05:00'); // EST timezone
expect(getUTCDateKey(nearMidnightUTC)).toBe('2025-08-26');
expect(getUTCDateKey(lateNightLocal)).toBe('2025-08-26'); // Should be same UTC day
});
it('should handle invalid dates gracefully', () => {
const invalidDate = new Date('invalid');
expect(getUTCDateKey(invalidDate)).toBe('unknown');
});
});
describe('getLocalDateKey', () => {
it('should extract local date string in YYYY-MM-DD format', () => {
const date = new Date('2025-08-26T14:30:00.000Z');
const result = getLocalDateKey(date);
expect(result).toMatch(/^\d{4}-\d{2}-\d{2}$/);
});
it('should handle timezone edge cases by using local date', () => {
// Create a date that's on different local vs UTC days
const lateNightLocal = new Date('2025-08-26T05:30:00.000Z'); // This might be Aug 25 local time
const result = getLocalDateKey(lateNightLocal);
expect(result).toMatch(/^\d{4}-\d{2}-\d{2}$/);
// The exact result depends on system timezone, but format should be consistent
});
it('should handle invalid dates gracefully', () => {
const invalidDate = new Date('invalid');
expect(getLocalDateKey(invalidDate)).toBe('unknown');
});
});
describe('getTodayUTCDateKey', () => {
it('should return today\'s date in YYYY-MM-DD format', () => {
const result = getTodayUTCDateKey();
expect(result).toMatch(/^\d{4}-\d{2}-\d{2}$/);
// Should match manual calculation
const expected = new Date().toISOString().split('T')[0];
expect(result).toBe(expected);
});
});
describe('getTodayLocalDateKey', () => {
it('should return today\'s local date in YYYY-MM-DD format', () => {
const result = getTodayLocalDateKey();
expect(result).toMatch(/^\d{4}-\d{2}-\d{2}$/);
// Should match manual calculation
const today = new Date();
const expected = `${today.getFullYear()}-${String(today.getMonth() + 1).padStart(2, '0')}-${String(today.getDate()).padStart(2, '0')}`;
expect(result).toBe(expected);
});
});
describe('formatDateName', () => {
beforeAll(() => {
// Mock Date.now to have consistent tests
jest.useFakeTimers();
jest.setSystemTime(new Date('2025-08-26T15:00:00.000Z'));
});
afterAll(() => {
jest.useRealTimers();
});
it('should format today as "Today"', () => {
const todayKey = '2025-08-26'; // Matches mocked system time
expect(formatDateName(todayKey)).toBe('Today');
});
it('should format yesterday as "Yesterday"', () => {
const yesterdayKey = '2025-08-25'; // Day before mocked system time
expect(formatDateName(yesterdayKey)).toBe('Yesterday');
});
it('should format other dates as weekday names', () => {
const fridayKey = '2025-08-22'; // Should be a Friday
expect(formatDateName(fridayKey)).toBe('Friday');
});
it('should handle invalid date keys gracefully', () => {
expect(formatDateName('invalid-date')).toBe('invalid-date');
expect(formatDateName('')).toBe('');
});
});
describe('isSameUTCDay', () => {
it('should return true for dates on the same UTC day', () => {
const morning = new Date('2025-08-26T08:00:00.000Z');
const evening = new Date('2025-08-26T20:00:00.000Z');
expect(isSameUTCDay(morning, evening)).toBe(true);
});
it('should return false for dates on different UTC days', () => {
const today = new Date('2025-08-26T08:00:00.000Z');
const tomorrow = new Date('2025-08-27T08:00:00.000Z');
expect(isSameUTCDay(today, tomorrow)).toBe(false);
});
it('should handle timezone edge cases correctly', () => {
const endOfDayEST = new Date('2025-08-26T23:59:00-05:00'); // 04:59 UTC next day
const startOfDayPST = new Date('2025-08-27T00:01:00-08:00'); // 08:01 UTC same day
// These are on the same UTC day (Aug 27)
expect(isSameUTCDay(endOfDayEST, startOfDayPST)).toBe(true);
});
});
describe('safeParseDate', () => {
it('should parse valid ISO date strings', () => {
const result = safeParseDate('2025-08-26T15:30:00.000Z');
expect(result).toBeInstanceOf(Date);
expect(result.toISOString()).toBe('2025-08-26T15:30:00.000Z');
});
it('should parse valid date strings', () => {
const result = safeParseDate('2025-08-26');
expect(result).toBeInstanceOf(Date);
expect(getUTCDateKey(result)).toBe('2025-08-26');
});
it('should return current date for invalid strings', () => {
const before = new Date();
const result = safeParseDate('invalid-date-string');
const after = new Date();
expect(result).toBeInstanceOf(Date);
expect(result.getTime()).toBeGreaterThanOrEqual(before.getTime());
expect(result.getTime()).toBeLessThanOrEqual(after.getTime());
});
});
describe('isValidUTCDateKey', () => {
it('should validate correct YYYY-MM-DD format', () => {
expect(isValidUTCDateKey('2025-08-26')).toBe(true);
expect(isValidUTCDateKey('2000-01-01')).toBe(true);
expect(isValidUTCDateKey('2099-12-31')).toBe(true);
});
it('should reject invalid formats', () => {
expect(isValidUTCDateKey('25-08-26')).toBe(false); // Wrong year format
expect(isValidUTCDateKey('2025-8-26')).toBe(false); // Missing zero padding
expect(isValidUTCDateKey('2025/08/26')).toBe(false); // Wrong separator
expect(isValidUTCDateKey('invalid')).toBe(false);
expect(isValidUTCDateKey('')).toBe(false);
});
});
describe('Real-world timezone scenarios', () => {
it('should handle memories created at different times on same local day', () => {
// Scenario: User creates 3 checkpoints on same calendar day in EST timezone
const morning = new Date('2025-08-26T09:00:00-05:00'); // 14:00 UTC
const afternoon = new Date('2025-08-26T15:00:00-05:00'); // 20:00 UTC
const lateNight = new Date('2025-08-26T23:45:00-05:00'); // 04:45 UTC next day!
const morningKey = getUTCDateKey(morning);
const afternoonKey = getUTCDateKey(afternoon);
const lateNightKey = getUTCDateKey(lateNight);
// The late night one will be on the next UTC day
expect(morningKey).toBe('2025-08-26');
expect(afternoonKey).toBe('2025-08-26');
expect(lateNightKey).toBe('2025-08-27'); // This is the timezone challenge!
// This is EXPECTED behavior - UTC grouping prevents ambiguity
expect(morningKey).not.toBe(lateNightKey);
});
});
});