Add unit tests for kzg, evals, composer, runtime and errors

[HDauven]

Resolves #862

[Copilot]

Pull request overview

This PR adds comprehensive unit test coverage for several core modules in the codebase, including KZG commitment schemes, evaluations, composer components, runtime, and error handling.

Changes:

• Added unit tests for runtime event handling and default initialization
• Added tests for FFT evaluations including serialization, interpolation, and arithmetic operations
• Added comprehensive error display and conversion tests
• Added tests for gate, witness, and ECC data structures
• Added KZG proof aggregation and commitment tests

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/runtime.rs	Tests runtime initialization and event handling without panicking
src/fft/evaluations.rs	Tests evaluations serialization, interpolation, arithmetic operations, and domain validation
src/error.rs	Tests error variant display formatting and conversions
src/composer/gate.rs	Tests gate structure traits (Copy, Clone, Eq, PartialEq, Debug)
src/composer/constraint_system/witness.rs	Tests witness constants, indexing, and WireData variants
src/composer/constraint_system/ecc.rs	Tests WitnessPoint and WnafRound structure accessors
src/commitment_scheme/kzg10/proof.rs	Tests aggregate proof flattening and linear combination logic
src/commitment_scheme/kzg10/commitment.rs	Tests commitment default initialization and conversion from projective coordinates

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[codecov]

Codecov Report

❌ Patch coverage is 93.33333% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 86.82%. Comparing base (16ad7e0) to head (7b842f3).

Files with missing lines	Patch %	Lines
src/fft/evaluations.rs	91.93%	5 Missing ⚠️
src/composer/constraint_system/witness.rs	77.77%	2 Missing ⚠️
src/error.rs	77.77%	2 Missing ⚠️

Additional details and impacted files

@@                    Coverage Diff                     @@
##           stable-tool-chain-msrv     #858      +/-   ##
==========================================================
+ Coverage                   85.18%   86.82%   +1.64%     
==========================================================
  Files                          57       57              
  Lines                        3713     3849     +136     
==========================================================
+ Hits                         3163     3342     +179     
+ Misses                        550      507      -43     

Files with missing lines	Coverage Δ
src/commitment_scheme/kzg10/commitment.rs	59.25% <100.00%> (+19.25%)	⬆️
src/commitment_scheme/kzg10/proof.rs	67.64% <100.00%> (+34.31%)	⬆️
src/composer/gate.rs	100.00% <100.00%> (+100.00%)	⬆️
src/runtime.rs	50.00% <100.00%> (+40.00%)	⬆️
src/composer/constraint_system/witness.rs	71.42% <77.77%> (+46.42%)	⬆️
src/error.rs	68.96% <77.77%> (+63.70%)	⬆️
src/fft/evaluations.rs	83.18% <91.93%> (+43.97%)	⬆️

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[xevisalle]

Some tests are OK. However, the ones that simply assert that an instantiation or copy is correct, I think they could be removed... It adds LoC and complexity. What do you think?

[HDauven]

Some tests are OK. However, the ones that simply assert that an instantiation or copy is correct, I think they could be removed... It adds LoC and complexity. What do you think?

I removed the tests you pointed out. It only dropped coverage by a very tiny amount, as most of the calls are covered by other tests.