Simplify compute_asset_desc_hash function

[ConstanceBeguier]

Update compute_asset_desc_hash function

• Now accepts &NonEmpty<u8> instead of &[u8]
• Returns [u8; 32] directly (no longer wrapped in Result)
• Panics if asset_desc is not valid UTF-8

Update get_burn_tuple function

• Now takes asset_desc_hash as input instead of asset_desc
• Changes the function’s visibility to private

Cleanup unused code

• Removed unused errors: WrongAssetDescSize, InvalidAssetDescHashLength
• Removed unused constant: MAX_ASSET_DESCRIPTION_SIZE
• Removed unused function: is_asset_desc_of_valid_size

[Copilot]

Pull Request Overview

This PR simplifies the compute_asset_desc_hash function in accordance with the new ZIP227 spec by requiring nonempty asset descriptions and removing now-unneeded error variants.

• Converts asset_desc from a slice to a NonEmpty type in several modules.
• Eliminates error handling for invalid sizes by using NonEmpty::from_slice with an expect message.
• Removes the is_asset_desc_of_valid_size helper and related error variants.

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/zsa.rs	Updated compute_asset_desc_hash call to use NonEmpty rather than unwrap a Result.
tests/issuance_global_state.rs	Adjusted multiple compute_asset_desc_hash calls to adopt the NonEmpty approach.
src/note/asset_base.rs	Modified random asset generation to use NonEmpty and removed the unused asset_desc size check.
src/issuance.rs	Simplified compute_asset_desc_hash; updated tests and removed error propagation.
src/bundle/burn_validation.rs	Updated compute_asset_desc_hash invocation to use NonEmpty.

[ConstanceBeguier]

I just rebased on zsa1 branch

[PaulLaux]

added some comments for extra consistency. Also:

• please fix issue_bundle_asset_desc_roundtrip() I'm not sure what it checks now but it is surly not seet_desc roundtrip. Let's simplify it to check one asset_desc roundtrip. The end of the test should compute the hash again and check that we can get it via get_action_by_desc_hash()

Separate " // Not well-formed as per Unicode 15.0 specification, Section 3.9, D92" to a different test. We want to fail on non-unicode strings. right?

[ConstanceBeguier]

It seems that the check on UTF-8 encoding is not done in Orchard.

I updated the issue_bundle_asset_desc_roundtrip test to remove not well-formed UTF-8

[PaulLaux]

approved with minor comments

[PaulLaux]

can we add a From<> trait for NonEmpty in our code so we can do b"Asset 1".into() ?

[ConstanceBeguier]

I think it is not possible because neither From nor NonEmpty are defined in the current crate.