Implementing Test Suite for k4ActsTracking Package

[madbaron]

This issue proposes a comprehensive set of tests to be included in the k4ActsTracking package, aiming to improve package robustness and maintainability. These recommendations are based on current repository structure, typical HEP tracking workflows, and standard best practices.

Please discuss or extend as appropriate.

This is an attempt at getting copilot/agents to do as much as possible of the heavy-lifting (the plan below was also written by the AI)

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Proposed Test Suite for k4ActsTracking

1. Unit Tests

Geometry Service

• Initialization of ActsGeoSvc with DD4hep
• Tracking geometry construction
• Surface lookup and retrieval
• Geometry context creation and validation
• Material decorator application

Helper Functions

• Track conversions between ACTS and EDM4HEP
• Coordinate/parameter transformations
• Covariance/error propagation checks

2. Algorithm Component Tests

ACTSSeededCKFTrackingAlg

• Valid configuration/init
• Seed creation from tracker hits
• CKF track finding with simple mocks
• Output track collection correctness
• Empty/noise-only input handling
• Magnetic field usage tests
• Performance (timing benchmarks)

ACTSDuplicateRemoval

• Duplicate identification and removal logic
• Best track quality preservation
• Edge cases: single track, no duplicates, all duplicates
• Output validation

FilterTracksAlg

• Hit count, chi2, pT, and other filter cut handling
• Physics cut application correctness
• Edge cases and misconfigurations

TrackTruthAlg

• Track/MC particle association logic
• Simulated hit relation logic
• Single- and multi-MC scenarios
• Output mapping quality

3. Integration Tests

Full Tracking Chain

• Workflow from hits → seeds → tracks
• Realistic detector (ODD) handling
• With simulated/known-good particle events
• Efficiency and correctness checks

Service Integration

• Various detector/magnetic field configs
• Calibration and geometry context
• Concurrent service use

4. Validation Tests

Physics Validation

• Track parameter and impact parameter resolution
• Momentum and d0/z0 reconstruction accuracy
• Track finding efficiency and fake rate

Data Format Tests

• EDM4HEP I/O and object creation
• Collection subset persistence

5. Regression Tests

• Store reference standard outputs for key cases
• Alert on significant result/performance changes

6. CI/CD Practices

• Run geometry/service/algorithm tests per PR
• Full integration/physics validation nightly or weekly
• Store artifacts and generate metrics/coverage reports

7. Test Data Needs

• Sample tracker hits, truth, reference geometries
• Edge case and boundary condition scenarios

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Feedback, extensions, and concrete test implementations are encouraged!