New cost model

[arvidn]

Note

High Risk
Consensus and CLVM cost/limit behavior change at defined heights; incorrect flag gating would diverge from network rules and affect block/spend validation.

Overview
Bumps clvmr / clvm-fuzzing to 0.19.0 and wires two new dialect flags—LIMITS and NEW_COST_MODEL—through ConsensusFlags and the from_clvm_flags / to_clvm_flags conversions so Python and Rust stay bit-aligned with clvmr.

Height-gated behavior in get_flags_for_height_and_constants changes: NEW_COST_MODEL turns on with hard fork 2 alongside the existing HF2 bundle. Soft fork 8’s DISABLE_OP and LIMITS are now applied only in the else if branch (after soft fork 8 but before hard fork 2), so those transitional rules stop once HF2 activates.

^{Reviewed by Cursor Bugbot for commit ddefb84. Bugbot is set up for automated code reviews on this repo. Configure here.}

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	cargo/​clvmr@​0.18.0 ⏵ 0.19.0
	cargo/​clvm-fuzzing@​0.18.0 ⏵ 0.19.0

View full report

[coveralls-official]

Coverage Report for CI Build 31037445434

Coverage increased (+0.8%) to 82.676%

Details

• Coverage increased (+0.8%) from the base build.
• Patch coverage: 4 uncovered changes across 1 file (13 of 17 lines covered, 76.47%).
• 2 coverage regressions across 1 file.

Uncovered Changes

File	Changed	Covered	%
crates/chia-consensus/src/spendbundle_validation.rs	5	1	20.0%
Total (2 files)	17	13	76.47%

Coverage Regressions

2 previously-covered lines in 1 file lost coverage.

File	Lines Losing Coverage	Coverage
crates/chia-consensus/src/spendbundle_validation.rs	2	94.31%

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Coverage Stats

Relevant Lines:	19851
Covered Lines:	16412
Line Coverage:	82.68%
Coverage Strength:	11149570.78 hits per line

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💛 - Coveralls

[arvidn]

@cursor review

[cursor]

✅ Bugbot reviewed your changes and found no new issues!

Comment @cursor review or bugbot run to trigger another review on this PR

^{Reviewed by Cursor Bugbot for commit ddefb84. Configure here.}