Testing · Middle · Question 9 of 75

How do you fix the current date in a test?

✓Correct answer: vi.useFakeTimers(); vi.setSystemTime(new Date("2026-01-01")) (in Jest: jest.setSystemTime)
2Change the computer's clock in CI
3Mock Date.now only - new Date() will follow

Explanation

Code that shows “today” or computes expiry otherwise fails on certain dates or in other time zones.

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