add stack info to log string for block validation for unknown error

[emlowe]

For some temporary debugging for simulator errors propogate up the stack trace if some exception happens during block validation (which causes the UNKNOWN error to be propogated)

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Note

Adds stack trace propagation for block pre-validation failures to aid debugging.

• Extends PreValidationResult with extra_string to carry traceback text
• On exceptions in _pre_validate_block, returns Err.UNKNOWN with extra_string populated
• In FullNode.add_block, includes extra_string in raised error message when pre-validation fails

^{Written by Cursor Bugbot for commit 1782220. This will update automatically on new commits. Configure here.}

[cursor]

Temporary debugging code included in production

Low Severity

The PR description explicitly states this is "For some temporary debugging for simulator errors." This suggests the code adding extra_string field and stack trace propagation was intended for temporary debugging and may not be meant for production. The stack trace is already being logged via log.error(f"Exception: {error_stack}"), so adding it to the ValueError message and storing it in a Streamable field appears to be debugging-specific behavior that could be removed once the simulator issues are resolved.

🔬 Verification Test

Why verification test was not possible: This is a code quality/intentionality issue rather than a functional bug. The code functions correctly - it adds stack trace information to error messages. The concern is whether this temporary debugging code should be committed to production, as explicitly stated in the PR description. This requires human judgment about whether the feature is intended to be permanent or should be removed after debugging is complete.

Additional Locations (2)

• chia/consensus/multiprocess_validation.py#L161-L164
• chia/full_node/full_node.py#L2166-L2167

 

[github-actions]

File	Coverage	Missing Lines
chia/consensus/multiprocess_validation.py	50.0%	lines 162

Total	Missing	Coverage
2 lines	Unknown	50%

[coveralls-official]

Pull Request Test Coverage Report for Build 20869836106

Details

• 1 of 2 (50.0%) changed or added relevant lines in 1 file are covered.
• 31 unchanged lines in 8 files lost coverage.
• Overall coverage increased (+0.008%) to 90.827%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
chia/consensus/multiprocess_validation.py	1	2	50.0%

Files with Coverage Reduction	New Missed Lines	%
chia/full_node/full_node.py	1	87.21%
chia/_tests/simulation/test_simulation.py	1	96.49%
chia/_tests/core/test_farmer_harvester_rpc.py	2	98.06%
chia/timelord/timelord_launcher.py	2	70.0%
chia/server/node_discovery.py	3	80.86%
chia/wallet/wallet_node.py	4	86.39%
chia/daemon/server.py	7	80.62%
chia/timelord/timelord.py	11	72.0%

Totals
Change from base Build 20864058213:	0.008%
Covered Lines:	102890
Relevant Lines:	113110

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💛 - Coveralls