Added e2e tests of blake improvement.

[orizi]

Summary

Enhanced Blake2s hash tests with new utility functions and comprehensive test coverage. Added blake2s_finalize_guarantees import, converted test assertions to use u256 format instead of raw arrays, and introduced a new test for the guarantees-based Blake2s function with proper message construction utilities.

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Type of change

Please check one:

• Bug fix (fixes incorrect behavior)
• New feature
• Performance improvement
• Documentation change with concrete technical impact
• Style, wording, formatting, or typo-only change

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Why is this change needed?

The existing Blake2s tests were using raw array comparisons and lacked coverage for the guarantees-based Blake2s functions. This change provides better test coverage and more readable assertions by converting hash outputs to u256 format, while also adding comprehensive tests for the blake2s_finalize_guarantees function.

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What was the behavior or documentation before?

Tests compared Blake2s hash outputs as raw u32 arrays and only tested the basic blake2s_compress and blake2s_finalize functions. There was no test coverage for blake2s_finalize_guarantees or utility functions for message construction.

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What is the behavior or documentation after?

Tests now compare hash outputs as u256 values for better readability, include comprehensive testing of blake2s_finalize_guarantees with proper message construction from felt252 values, and provide utility functions for converting between different data formats used in Blake2s operations.

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Related issue or discussion (if any)

N/A

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Additional context

The changes include a new to_u256 conversion function and a msg module with utilities for constructing Blake2s input messages from felt252 values using bounded integer guarantees. The test data also includes new end-to-end test cases for hashing two felt252 values, demonstrating practical usage patterns.

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Note

Low Risk
Low risk because changes are limited to test code and e2e fixtures, with no production hashing implementation modified. Main risk is test brittleness due to new u256 formatting and bounded-int guarantee message construction.

Overview
Updates Blake2s unit tests to assert outputs as a single u256 value (via a new to_u256 helper) instead of raw [u32; 8] arrays.

Adds new coverage for blake2s_finalize_guarantees, including utilities to build Blake2sInputGuarantee messages from two felt252 values using bounded-int guarantees, and extends the Blake e2e fixture to exercise hashing two felt252s with the guarantees-based finalize path (future Sierra enabled).

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[reviewable-StarkWare]

This change is 

[orizi]

• Added e2e tests of blake improvement. #9780 👈 (View in Graphite)
• feature(sierra): Added guarantee version for blake libfuncs. #9779
• feature(sierra): Added a split fn from u128 to u32 guarantees. #9778
• feature(sierra): Added BoundedIntGuarantee and verify libfunc. #9777
• main

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[ilyalesokhin-starkware]

@ilyalesokhin-starkware reviewed 2 files and all commit messages, and made 1 comment.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on orizi).

[orizi]

@orizi reviewed 1 file and all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on orizi).