test: add comprehensive unit tests for jira-utils functions (#1636)

[aarushlohit]

Summary

Added comprehensive Vitest unit tests for categorizeStatus and calculateMetrics to improve reliability, prevent regressions, and ensure correct behavior across normal, edge-case, and boundary-condition scenarios.

Closes #1636

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Type of Change

• Tests
• Bug fix
• New feature
• Documentation update
• Refactor / code cleanup

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Changes Made

• Added 42 comprehensive unit tests
• Added coverage for categorizeStatus
• Added coverage for calculateMetrics
• Tested happy-path scenarios
• Tested edge cases and boundary conditions
• Added null and undefined input handling tests
• Added type validation coverage
• Added date calculation validation
• Added large dataset testing
• Added rounding and consistency checks
• Added data integrity validation

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Test Coverage

categorizeStatus

Covered:

• Valid status categorization
• Boundary conditions
• Unexpected values
• Null inputs
• Undefined inputs
• Invalid input types
• Consistency checks

calculateMetrics

Covered:

• Metric calculations
• Date-based calculations
• Large dataset processing
• Empty datasets
• Missing values
• Rounding behavior
• Aggregation accuracy
• Data integrity checks
• Edge-case scenarios

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Testing

Executed using Vitest.

npx vitest run

Validation completed:

• All new tests pass
• Existing tests continue to pass
• Edge cases verified
• Boundary conditions verified
• Large datasets verified
• Data integrity validated

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Impact

• Improves confidence in analytics calculations
• Prevents regressions in status categorization logic
• Strengthens reliability of metrics generation
• Increases overall test coverage

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Additional Notes

The new test suite focuses on correctness, stability, and long-term maintainability by validating both expected behavior and uncommon edge cases that could otherwise lead to production regressions.

[vercel]

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[github-actions]

GSSoC Label Checklist 🏷️

@Priyanshu-byte-coder — please apply the appropriate labels before merging:

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• level:beginner — 20 pts
• level:intermediate — 35 pts
• level:advanced — 55 pts
• level:critical — 80 pts

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• quality:clean — ×1.2 multiplier
• quality:exceptional — ×1.5 multiplier

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