Template hash hardening (breaking change) - #143
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someone235 merged 4 commits intoJul 12, 2026
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Include fixed-width prefix and suffix lengths when validating template hashes in readInputStateWithTemplate and validateOutputStateWithTemplate. This changes the template hash format and breaks existing tests until Rust-side hash calculations and fixtures are updated.
Exposes templateHash(prefix, suffix), allowing contracts to reconstruct the canonical length-bound template hash from revealed template parts. Supports cases where a template hash is not committed directly, but is contained in a higher-level commitment such as a route table or a hash over several template hashes. The contract can open that commitment, reconstruct the individual template hash, and use it for state validation. Documents the builtin, updates template-related examples to use the canonical hash and camelCase naming, and adds an execution test proving that the prefix/suffix boundary affects the result.
- introduced a shared length-bound template hash helper - exposed the canonical hash through CompiledContract - migrated chess contracts and tests to templateHash - refreshed chess size snapshots and editor highlighting
- locked Rust and Sil hashing to shared canonical vectors - verified templateHash against both *WithTemplate builtins at runtime
someone235
approved these changes
Jul 12, 2026
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This PR changes the canonical template hash from:
H(prefix || suffix)to:
H(i64le(prefix.length) || prefix || i64le(suffix.length) || suffix)Lengths are encoded as fixed-width 8-byte little-endian integers.
This is a breaking change for contracts using
readInputStateWithTemplateorvalidateOutputStateWithTemplate. Existing template hashes must be recalculated.The new
templateHash(prefix, suffix)builtin exposes the canonical calculation to Silverscript contracts. Rust callers can usetemplate::template_hash(prefix, suffix)orCompiledContract::template_hash().