test_bal_invalid_noop_value_change()

Documentation for tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists_invalid.py::test_bal_invalid_noop_value_change@26332146.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists_invalid.py::test_bal_invalid_noop_value_change --fork Amsterdam

Test that clients reject a BAL balance/nonce/code change entry whose post-value equals the account's real, unchanged value.

Oracle legitimately appears in the BAL only via a storage read (slot 0 is read, not written). Its balance (0), nonce (1), and code are never touched by the transaction. The BAL is corrupted by appending a change entry for one of these fields whose post-value equals the account's actual unchanged value -- distinct from the wrong-value corruption covered elsewhere, since here post == pre exactly.

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

@pytest.mark.valid_from("Amsterdam")
@pytest.mark.exception_test
@pytest.mark.parametrize(
    "modifier",
    [
        pytest.param(
            lambda oracle, code: append_change(  # noqa: ARG005
                account=oracle,
                change=BalBalanceChange(block_access_index=1, post_balance=0),
            ),
            id="noop_balance_change",
        ),
        pytest.param(
            lambda oracle, code: append_change(  # noqa: ARG005
                account=oracle,
                change=BalNonceChange(block_access_index=1, post_nonce=1),
            ),
            id="noop_nonce_change",
        ),
        pytest.param(
            lambda oracle, code: append_change(
                account=oracle,
                change=BalCodeChange(block_access_index=1, new_code=code),
            ),
            id="noop_code_change",
        ),
    ],
)
def test_bal_invalid_noop_value_change(
    blockchain_test: BlockchainTestFiller,
    pre: Alloc,
    modifier: Callable,
) -> None:
    """
    Test that clients reject a BAL balance/nonce/code change entry whose
    post-value equals the account's real, unchanged value.

    Oracle legitimately appears in the BAL only via a storage read (slot
    0 is read, not written). Its balance (0), nonce (1), and code are
    never touched by the transaction. The BAL is corrupted by appending
    a change entry for one of these fields whose post-value equals the
    account's actual unchanged value -- distinct from the wrong-value
    corruption covered elsewhere, since here post == pre exactly.
    """
    alice = pre.fund_eoa()
    code = Op.SLOAD(0)
    oracle = pre.deploy_contract(code=code, storage={0: 0x42})

    tx = Transaction(sender=alice, to=oracle)

    blockchain_test(
        pre=pre,
        # The block reverts and the post state remains unchanged.
        post=pre,
        blocks=[
            Block(
                txs=[tx],
                exception=BlockException.INVALID_BLOCK_ACCESS_LIST,
                expected_block_access_list=BlockAccessListExpectation(
                    account_expectations={
                        alice: BalAccountExpectation(
                            nonce_changes=[
                                BalNonceChange(
                                    block_access_index=1, post_nonce=1
                                )
                            ],
                        ),
                        oracle: BalAccountExpectation(
                            storage_reads=[0],
                        ),
                    }
                ).modify(modifier(oracle=oracle, code=code)),
            )
        ],
    )

Parametrized Test Cases

This test generates 3 parametrized test cases across 1 fork.