test_sstore_restoration_then_reset()

Documentation for tests/amsterdam/eip8037_state_creation_gas_cost_increase/test_state_gas_sstore.py::test_sstore_restoration_then_reset@87aba1a3.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip8037_state_creation_gas_cost_increase/test_state_gas_sstore.py::test_sstore_restoration_then_reset --fork Amsterdam

Verify accounting across 0 to 1 to 0 to 1 (restore then re-set).

The refund applied at 1 to 0 returns state gas to the reservoir; the subsequent 0 to 1 re-charges state gas. Net: one charge remains, one state gas worth counted in block state gas.

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

@pytest.mark.valid_from("EIP8037")
def test_sstore_restoration_then_reset(
    blockchain_test: BlockchainTestFiller,
    pre: Alloc,
    fork: Fork,
) -> None:
    """
    Verify accounting across 0 to 1 to 0 to 1 (restore then re-set).

    The refund applied at 1 to 0 returns state gas to the reservoir;
    the subsequent 0 to 1 re-charges state gas.  Net: one charge
    remains, one state gas worth counted in block state gas.
    """
    sstore_state_gas = Op.SSTORE(new_value=1).state_cost(fork)
    intrinsic_gas = fork.transaction_intrinsic_cost_calculator()()

    code = (
        Op.SSTORE(0, 1)
        + Op.SSTORE.with_metadata(
            key_warm=True,
            original_value=0,
            current_value=1,
            new_value=0,
        )(0, 0)
        + Op.SSTORE.with_metadata(
            key_warm=True,
            original_value=0,
            current_value=0,
            new_value=1,
        )(0, 1)
    )
    tx_regular = intrinsic_gas + code.gas_cost(fork) - 2 * sstore_state_gas
    expected = max(tx_regular, sstore_state_gas)

    contract = pre.deploy_contract(code=code)
    tx = Transaction(
        to=contract,
        state_gas_reservoir=sstore_state_gas,
        sender=pre.fund_eoa(),
    )

    blockchain_test(
        pre=pre,
        blocks=[Block(txs=[tx], header_verify=Header(gas_used=expected))],
        post={contract: Account(storage={0: 1})},
    )

Parametrized Test Cases

This test generates 1 parametrized test case across 1 fork.