feat(cheatcodes): include trace information about setting account code in EIP7702 transaction

[tinchoabbate]

Component

Forge

Describe the feature you would like

In a forge test that uses the vm.signAndAttachDelegation (or vm.attachDelegation) cheatcode, it'd be helpful if the test's trace somehow showed the account's code being set. Right now the process is opaque for the devs, and it's unclear whether the account's code was updated or not.

For example, right now if I do:

vm.signAndAttachDelegation(address(delegateContract), bob.privateKey);
address(0).call("");

Then the trace shows:

├─ [0] VM::signAndAttachDelegation(DelegateContractV1: [0x8Ad159a275AEE56fb2334DBb69036E9c7baCEe9b], 25733205992525344549959058604562080613152606839721263039386232180585134200482 [2.573e76])
│   └─ ← [Return] (1, 0x30326dccdd7ff594b3bfa85acdb7a472414233bcfef3db1a3aeaa453d10891b9, 0x76aee582915fbaf1cc3105cd7c1f37d4dbb13eaf64117fd9e6447fb50d281a2f, 0, 0x8Ad159a275AEE56fb2334DBb69036E9c7baCEe9b)
├─ [0] 0x0000000000000000000000000000000000000000::fallback()
│   └─ ← [Stop] 

But there's nothing in the call to address(0) that signals the call has 7702 data attached and that it's setting code to an account.

Additional context

No response

[zerosnacks]

Definitively in support of adding this, good idea

cc @evchip

[evchip]

Thanks @tinchoabbate, I'll look into this.

[evchip]

@tinchoabbate thanks for reporting this. You're right that the delegation code write isn't visible in traces because we currently write directly to state rather than executing through the EVM.

@zerosnacks I propose we modify attachDelegation and signAndAttachDelegation to simulate a type-4 EIP-7702 transaction (in addition to the current state write) specifically to generate proper traces. This would give visibility into the delegation process while maintaining current test behavior.

Happy to implement this if the approach sounds reasonable. Let me know if you'd prefer a different solution.