feat: update SubAccount.formID to handle bigger numbers

[ENJATZ]

Motivation

I am having a scenario where I need to handle more than 256 subaccounts. This is my workaround for now:

const principal = identity.getPrincipal()

const generatedAccountId = AccountIdentifier.fromPrincipal({
    principal,
    subAccount: SubAccount.fromBytes(numberToUint8Array32(newIndexNumber)),
})

where numberToUint8Array32 is the updated fromID method.

Changes

Updates the SubAccount.fromID method to handle up to nine quadrillion subaccounts (which is the max safe int).

It creates a buffer of 32 bytes and uses writeBigInt64BE to write the id using a 24 offest.

Tests

Added one more test for fromID method under account_identifier.spec.ts. All tests are passing.

Todos

• Enjoy!

[sa-github-api]

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[peterpeterparker]

Hi,

Thanks for the PR.

Subaccounts seems indeed to be arbitrary 32-byte values source (I'm happy if one of my colleague confirm this) but I think NNS dapp limits the number of subaccounts to 256 source. That's why this limitation has probably been historically developed.

Therefore, the team would also need to replicate the logic in NNS dapp codebase before being able to merge this. I'm not mentioning this as a deal-breaker, just pointing out that it might require additional work on that side too.

[peterpeterparker]

Therefore, the team would also need to replicate the logic in NNS dapp codebase before being able to merge this. I'm not mentioning this as a deal-breaker, just pointing out that it might require additional work on that side too.

My colleague @lmuntaner pointed out that NNS dapp frontend actually does not seem to use Subaccount.fromId on the client side, except fromId(0), so actually it would probably not need further work on that side, that's good.

[peterpeterparker]

LGTM, thanks a lot!

[lmuntaner]

LGTM! Thanks!

[peterpeterparker]

@ENJATZ: We just released your change in @dfinity/ledger-icp@2.2.0. Let us know how it goes and thanks for the PR.