test_create_account_creation_charge()

Documentation for tests/amsterdam/eip8037_state_creation_gas_cost_increase/test_state_gas_create.py::test_create_account_creation_charge@5c024cbb.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip8037_state_creation_gas_cost_increase/test_state_gas_create.py::test_create_account_creation_charge --fork Amsterdam

Verify NEW_ACCOUNT is charged for a new account and refunded for a pre-existing balance-only leaf.

Empty init code means zero code deposit, so NEW_ACCOUNT is the only create state cost. A fresh target is charged it; a pre-existing balance-only target (balance, no code, zero nonce) refunds it on success. The probe SSTORE both confirms the create succeeded and makes state gas dominate, so gas_used drops by exactly NEW_ACCOUNT when refunded.

Source code in tests/amsterdam/eip8037_state_creation_gas_cost_increase/test_state_gas_create.py

@pytest.mark.parametrize(
    "target",
    [
        pytest.param("new", id="new_account"),
        pytest.param("existing", id="existing_account"),
    ],
)
@pytest.mark.with_all_create_opcodes()
@pytest.mark.valid_from("EIP8037")
def test_create_account_creation_charge(
    state_test: StateTestFiller,
    pre: Alloc,
    fork: Fork,
    create_opcode: Op,
    target: str,
) -> None:
    """
    Verify NEW_ACCOUNT is charged for a new account and refunded for a
    pre-existing balance-only leaf.

    Empty init code means zero code deposit, so NEW_ACCOUNT is the only
    create state cost. A fresh target is charged it; a pre-existing
    balance-only target (balance, no code, zero nonce) refunds it on
    success. The probe SSTORE both confirms the create succeeded and
    makes state gas dominate, so gas_used drops by exactly NEW_ACCOUNT
    when refunded.
    """
    new_account = fork.gas_costs().NEW_ACCOUNT
    sstore_state_gas = Op.SSTORE(new_value=1).state_cost(fork)
    mstore_value, size = init_code_at_high_bytes(Op.STOP)
    create_call = (
        create_opcode(value=0, offset=0, size=size, salt=0)
        if create_opcode == Op.CREATE2
        else create_opcode(value=0, offset=0, size=size)
    )

    storage = Storage()
    factory = pre.deploy_contract(
        code=Op.MSTORE(0, mstore_value)
        + Op.SSTORE(
            storage.store_next(1, "create_succeeds"), Op.GT(create_call, 0)
        )
    )

    # Factory deployed via deploy_contract starts at nonce 1.
    if create_opcode == Op.CREATE2:
        create_address = compute_create2_address(
            address=factory, salt=0, initcode=bytes(Op.STOP)
        )
    else:
        create_address = compute_create_address(address=factory, nonce=1)
    if target == "existing":
        pre.fund_address(create_address, amount=1)

    tx = Transaction(
        to=factory,
        state_gas_reservoir=new_account + sstore_state_gas,
        sender=pre.fund_eoa(),
    )

    # State gas dominates regular: a new account adds NEW_ACCOUNT on top
    # of the probe SSTORE, a pre-existing target refunds it.
    expected = sstore_state_gas + (new_account if target == "new" else 0)
    state_test(
        pre=pre,
        tx=tx,
        post={factory: Account(storage=storage)},
        blockchain_test_header_verify=Header(gas_used=expected),
    )

Parametrized Test Cases

This test generates 4 parametrized test cases across 1 fork.