- Add Clock interface with Now() and From(t time.Time) methods
- Implement DefaultClock using time.Now() for production code
- Implement FixedClock with fixed time for deterministic testing
- Add factory functions NewClock() and NewFixedClock(time.Time)
- Comprehensive unit tests demonstrating deterministic test patterns
- Edge case testing (epoch, year 0001, year 9999, nanoseconds)
- Timezone preservation tests
- Example tests showing test usage patterns
- Performance benchmarks for both clock implementations
- 100% test coverage (exceeds 95% requirement)
All acceptance criteria met:
✓ Clock interface defined
✓ DefaultClock implementation using time.Now()
✓ FixedClock implementation with fixed time
✓ NewClock() factory function
✓ NewFixedClock(time.Time) factory function
✓ Unit tests demonstrating deterministic test patterns
✓ Godoc comments
✓ Example test showing test usage pattern
- Add Date struct with time.Time and Lang fields
- Implement package-level constructors: Now(), From(time.Time)
- Add conversion methods: Time(), Unix(), FromUnix(int64)
- Support negative Unix timestamps (dates before 1970)
- Support full time.Time range (year 0001-9999+)
- Add WithLang() for i18n support (placeholder)
- Create package documentation in quando.go
- Comprehensive unit tests with 100% coverage
- Example tests for godoc
- Verify immutability through tests
All acceptance criteria met:
✓ Date struct defined with time.Time and Lang fields
✓ Now() returns current date
✓ From(time.Time) converts to Date
✓ Time() extracts underlying time.Time
✓ Unix() returns Unix timestamp (int64)
✓ FromUnix(int64) creates Date from timestamp
✓ Unit tests with 100% coverage (exceeds 95% requirement)
✓ Godoc comments for all exported types/functions
✓ Example tests in example_test.go
