DevTooling: Implement differential testing between contract implementations

[Smartdevs17]

Description

Different contract implementations (e.g., upgraded vs original) should be tested differentially to catch behavioral changes.

Context: Differential testing catches subtle behavioral changes that unit tests miss.

Current Limitation: Likely lacks differential testing.

Expected Outcome: Implement framework comparing outputs across contract versions.

Acceptance Criteria

• Test harness for multiple implementations
• Property-based comparison tests
• Divergence detection and reporting
• Migration verification tests
• CI integration for regression detection
• Test results documentation
• Maintenance as implementations evolve

Technical Scope

Files likely affected: Test suite, comparison tools

APIs/Contracts involved: Old and new contract versions

Edge cases to consider:

• Non-deterministic behavior
• State-dependent outputs
• Performance differences
• Storage layout differences

[soyaya]

@soyaya has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

For this issue, I will:

Set up a differential testing framework that runs the same inputs across multiple contract implementations
Define invariant checks to detect any divergence in outputs, state changes, and events
Cover edge cases such as liquidation thresholds, interest calculations, and rounding behavior
Integrate the tests into CI so regressions are caught immediately
Document the testing approach so contributors can extend it easily

My approach is to isolate logic, generate controlled test cases, and ensure both implementations behave identically under all expected conditions. I move fast, communicate clearly, and deliver complete solutions with tests, not partial fixes.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @soyaya to this issue.

[drips-wave]

Congratulations, @soyaya! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on April 29, 2026.

🧑‍💻 @soyaya: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊

[soyaya]

Thank you right on it

[soyaya]

fixed