test_create_child_spill_not_double_charged()

Documentation for tests/amsterdam/eip8037_state_creation_gas_cost_increase/test_state_gas_create.py::test_create_child_spill_not_double_charged@8acae1b0.

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_child_spill_not_double_charged --fork Amsterdam

Test CREATE/CREATE2 child state gas paid from gas_left is not recharged.

The factory executes below the Amsterdam tx gas cap, so the CREATE child pays new-account and storage state gas by spilling from gas_left. The gas limit covers that bill once, so charging the same state growth again at frame end would run the transaction out of gas.

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

@pytest.mark.parametrize("enough_gas", [False, True])
@pytest.mark.with_all_create_opcodes
@pytest.mark.valid_from("EIP8037")
def test_create_child_spill_not_double_charged(
    state_test: StateTestFiller,
    pre: Alloc,
    fork: Fork,
    create_opcode: Op,
    enough_gas: bool,
) -> None:
    """
    Test CREATE/CREATE2 child state gas paid from `gas_left` is not recharged.

    The factory executes below the Amsterdam tx gas cap, so the CREATE child
    pays new-account and storage state gas by spilling from `gas_left`. The
    gas limit covers that bill once, so charging the same state growth again
    at frame end would run the transaction out of gas.
    """
    init_code = sum(Op.SSTORE(i, i + 1) for i in range(6)) + Op.STOP
    mstore_value, initcode_size = init_code_at_high_bytes(init_code)

    factory_code = Op.MSTORE(
        0,
        mstore_value,
        # gas accounting
        new_memory_size=32,
    ) + (
        create_opcode(
            value=0,
            offset=0,
            size=initcode_size,
            # gas accounting
            init_code_size=initcode_size,
        )
    )
    factory = pre.deploy_contract(code=factory_code)
    created = compute_create_address(
        address=factory,
        salt=0,
        nonce=1,
        initcode=init_code,
        opcode=create_opcode,
    )

    # The child's grant is short a 64th of what the factory holds at
    # dispatch, so its bill has to be grossed up by that fraction.
    child_gas = init_code.gas_cost(fork)
    gas_limit = (
        fork.transaction_intrinsic_cost_calculator()()
        + factory_code.gas_cost(fork)
        + child_gas * 64 // 63
    )
    if not enough_gas:
        gas_limit -= 1

    tx = Transaction(
        to=factory,
        gas_limit=gas_limit,
        sender=pre.fund_eoa(),
    )

    post = {
        created: Account(nonce=1, storage={i: i + 1 for i in range(6)})
        if enough_gas
        else Account.NONEXISTENT,
    }
    state_test(pre=pre, post=post, tx=tx)

Parametrized Test Cases

This test generates 4 parametrized test cases across 1 fork.