test_cross_frame_refund_repays_spill_in_inner_frame()

Documentation for tests/amsterdam/eip8037_state_creation_gas_cost_increase/test_state_gas_cross_frame_refund.py::test_cross_frame_refund_repays_spill_in_inner_frame@622620d8.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip8037_state_creation_gas_cost_increase/test_state_gas_cross_frame_refund.py::test_cross_frame_refund_repays_spill_in_inner_frame --fork Amsterdam

Test the repayment lands at an inner frame's merge.

The spill, the clearing call and both gas_left reads live in a depth-one frame, so an implementation reconciling the pools only when control returns to the top-level frame fails. Half-slot funding also checks that the inner merge repays only the spilled gas from the full-slot refund.

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

@pytest.mark.parametrize(
    "fund_half_slot",
    [False, True],
    ids=["empty-reservoir", "half-slot-reservoir"],
)
@pytest.mark.valid_from("EIP8037")
def test_cross_frame_refund_repays_spill_in_inner_frame(
    state_test: StateTestFiller,
    pre: Alloc,
    fork: Fork,
    fund_half_slot: bool,
) -> None:
    """
    Test the repayment lands at an inner frame's merge.

    The spill, the clearing call and both `gas_left` reads live in a
    depth-one frame, so an implementation reconciling the pools only
    when control returns to the top-level frame fails. Half-slot funding
    also checks that the inner merge repays only the spilled gas from
    the full-slot refund.
    """
    sstore_state_gas = Op.SSTORE(new_value=1).state_cost(fork)
    reservoir = sstore_state_gas // 2 if fund_half_slot else 0
    spilled = sstore_state_gas - reservoir

    clearer = pre.deploy_contract(code=Op.SSTORE(SLOT_X, 0))
    window = Op.POP(Op.DELEGATECALL(address=clearer))
    middle = pre.deploy_contract(
        code=clearing_probe_code(Op.SSTORE(SLOT_X, 1), [window] * 3)
    )
    contract = pre.deploy_contract(
        code=Op.POP(Op.DELEGATECALL(address=middle))
    )

    tx = Transaction(
        to=contract,
        state_gas_reservoir=reservoir,
        sender=pre.fund_eoa(),
    )

    post = {
        contract: Account(
            storage={
                SLOT_X: 0,
                SLOT_MARKER: 1,
                SLOT_INCREASED: 1,
                SLOT_RESULT: -spilled,
            }
        )
    }
    state_test(pre=pre, post=post, tx=tx)

Parametrized Test Cases

This test generates 2 parametrized test cases across 1 fork.