Account ID Follow-Up Tasks

[PhilippGackstatter]

These are tasks left over from the account ID refactor (#982).

• Introduce AccountIdError. There are now new error conditions for IDs and a separate error might be cleaner.
  • With the introduction of this error it might be possible to make AccountId::new_dummy a const fn and then we could possibly replace the somewhat duplicate functionality of miden_objects::testing::account_id::account_id.
• Implement Display for AccountType and use it in error messages.
• Remove unnecessary code in generate_account_seed. See also: Extend AccountId to two Felts and refactor creation process #982 (comment)
• Remove build.rs constants patching for POW which we no longer have.
• Move type, storage mode, version out into their own modules to reduce size of account_id.rs. See also Extend AccountId to two Felts and refactor creation process #982 (comment).
• Move newly introduced duplicate procedures into the new util library (seems like it's being done in Remove duplicate procedures from miden-lib #1002 already).
• Go through error messages and double check if they are up to date (e.g. ones previously mentioning "account id" should now likely mention first or second felt for accuracy).
• validate_fungible_asset_origin validates the account ID and then calls validate_fungible_asset which validates it again check if we can remove some redundancy here.
• Add new tests for changed things: version and epoch in ID, test new and changed MASM procedures more thoroughly.
  • See TODO in create_account_invalid_seed.
• Add AccountId version wrapper (see Extend AccountId to two Felts and refactor creation process #982 (comment)) and consider making ID V1 validation a separate procedure in MASM.
• Consider taking required parameters in AccountBuilder::new, i.e.: Extend AccountId to two Felts and refactor creation process #982 (comment).
• Consistently capitalize "account id" as "account ID".
• Rename first and second felt (and id_hi and id_lo) to prefix and suffix.
• With epoch taken as a concept of the protocol, we should probably change NoteExecutionHint::OnBlockSlot to not use epoch, as it is a somewhat different concept. See Extend AccountId to two Felts and refactor creation process #982 (comment) for details.
• Make u128::to_be_bytes and <[u8; 15]> encodings consistent (see Extend AccountId to two Felts and refactor creation process #982 (comment)).
  • This would be fundamentally at odds with current asset serialization where the first byte is assumed to be the account ID metadata. Since we can't change u128::to_be_bytes the metadata would not be in the first byte.
  • One approach may be to implement a special account ID serialization for assets where the first byte is the metadata byte, while the above formats for account IDs are the same.
• Use more precise truncation strategy for less subtleness: Extend AccountId to two Felts and refactor creation process #982 (comment)
• Consider adding faucet_id_prefix to Assets and rename Asset::faucet_id to Asset::faucet_id_prefix (Extend AccountId to two Felts and refactor creation process #982 (comment), Extend AccountId to two Felts and refactor creation process #982 (comment))
• Consider creating benchmarks for single and concurrent account id computation (Extend AccountId to two Felts and refactor creation process #982 (comment))
• Encapsulate behavior like is account a faucet check behind utility methods (Extend AccountId to two Felts and refactor creation process #982 (comment))
• Validate all metadata (account type, storage mode) in validate_id MASM procedure (Extend AccountId to two Felts and refactor creation process #982 (comment))
• Differentiate between "pure" and "instance" account procedures (Extend AccountId to two Felts and refactor creation process #982 (comment))
• Update ChainMmr docs to also say that it is being used for account id validation next to note authentication.

[bobbinth]

This is basically done now, right? I think the two remaining tasks will be done as a part of #1002.

[PhilippGackstatter]

Yes, if those tasks are handled in #1002 then let's close this as completed in #1054, #1055 and #1058.