test_bal_extcodecopy_and_oog()

Documentation for tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists_opcodes.py::test_bal_extcodecopy_and_oog@c74f1a67.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists_opcodes.py::test_bal_extcodecopy_and_oog --fork Amsterdam

Ensure BAL handles EXTCODECOPY and OOG during EXTCODECOPY appropriately.

Tests various OOG scenarios: - success: EXTCODECOPY completes, target appears in BAL - oog_at_cold_access: OOG before cold access, target NOT in BAL - oog_at_memory_large_offset: OOG at memory expansion (large offset), target NOT in BAL - oog_at_memory_boundary: OOG at memory expansion (boundary case), target NOT in BAL

Gas for all components (cold access + copy + memory expansion) must be checked BEFORE recording account access.

Source code in tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists_opcodes.py

@pytest.mark.parametrize(
    "oog_scenario,memory_offset,copy_size",
    [
        pytest.param("success", 0, 0, id="successful_extcodecopy"),
        pytest.param("oog_at_cold_access", 0, 0, id="oog_at_cold_access"),
        pytest.param(
            "oog_at_memory_large_offset",
            0x10000,
            32,
            id="oog_at_memory_large_offset",
        ),
        pytest.param(
            "oog_at_memory_boundary",
            256,
            32,
            id="oog_at_memory_boundary",
        ),
    ],
)
def test_bal_extcodecopy_and_oog(
    pre: Alloc,
    blockchain_test: BlockchainTestFiller,
    fork: Fork,
    oog_scenario: str,
    memory_offset: int,
    copy_size: int,
) -> None:
    """
    Ensure BAL handles EXTCODECOPY and OOG during EXTCODECOPY appropriately.

    Tests various OOG scenarios:
    - success: EXTCODECOPY completes, target appears in BAL
    - oog_at_cold_access: OOG before cold access, target NOT in BAL
    - oog_at_memory_large_offset: OOG at memory expansion (large offset),
      target NOT in BAL
    - oog_at_memory_boundary: OOG at memory expansion (boundary case),
      target NOT in BAL

    Gas for all components (cold access + copy + memory expansion) must be
    checked BEFORE recording account access.
    """
    alice = pre.fund_eoa()

    # Create target contract with some code
    target_contract = pre.deploy_contract(code=Op.PUSH1(0x42) + Op.STOP)

    # Full EXTCODECOPY: access + copy + memory expansion
    extcodecopy_code = Op.EXTCODECOPY(
        address=target_contract,
        dest_offset=memory_offset,
        offset=0,
        size=copy_size,
        address_warm=False,
        data_size=copy_size,
        new_memory_size=memory_offset + copy_size,
    )

    extcodecopy_contract = pre.deploy_contract(code=extcodecopy_code + Op.STOP)

    intrinsic_gas_cost = fork.transaction_intrinsic_cost_calculator()()

    if oog_scenario == "success":
        # Provide enough gas for everything including memory expansion
        tx_gas_limit = intrinsic_gas_cost + extcodecopy_code.gas_cost(fork)
        target_in_bal = True
    elif oog_scenario == "oog_at_cold_access":
        # Provide gas for pushes but 1 less than cold access
        extcodecopy_access_only = Op.EXTCODECOPY(
            address=target_contract,
            dest_offset=memory_offset,
            offset=0,
            size=copy_size,
            address_warm=False,
            data_size=0,
            new_memory_size=0,
        )
        tx_gas_limit = (
            intrinsic_gas_cost + extcodecopy_access_only.gas_cost(fork) - 1
        )
        target_in_bal = False
    elif oog_scenario == "oog_at_memory_large_offset":
        # Provide gas for push + cold access + copy, but NOT memory expansion
        extcodecopy_no_mem = Op.EXTCODECOPY(
            address=target_contract,
            dest_offset=memory_offset,
            offset=0,
            size=copy_size,
            address_warm=False,
            data_size=copy_size,
            new_memory_size=0,
        )
        tx_gas_limit = intrinsic_gas_cost + extcodecopy_no_mem.gas_cost(fork)
        target_in_bal = False
    elif oog_scenario == "oog_at_memory_boundary":
        # Calculate full cost and provide exactly 1 less than needed
        tx_gas_limit = intrinsic_gas_cost + extcodecopy_code.gas_cost(fork) - 1
        target_in_bal = False
    else:
        raise ValueError(f"Invariant: unknown oog_scenario {oog_scenario}")

    tx = Transaction(
        sender=alice,
        to=extcodecopy_contract,
        gas_limit=tx_gas_limit,
    )

    block = Block(
        txs=[tx],
        expected_block_access_list=BlockAccessListExpectation(
            account_expectations={
                extcodecopy_contract: BalAccountExpectation.empty(),
                **(
                    {target_contract: BalAccountExpectation.empty()}
                    if target_in_bal
                    else {target_contract: None}
                ),
            }
        ),
    )

    blockchain_test(
        pre=pre,
        blocks=[block],
        post={
            alice: Account(nonce=1),
            extcodecopy_contract: Account(),
            target_contract: Account(),
        },
    )

Parametrized Test Cases

This test generates 4 parametrized test cases across 1 fork.