test_bal_invalid_noop_storage_change()

Documentation for tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists_invalid.py::test_bal_invalid_noop_storage_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_storage_change --fork Amsterdam

Test that clients reject a BAL storage change whose post-value equals the value already present at the start of the transaction.

Oracle performs a round-trip write: SSTORE(0, 0x42) with slot 0 already at 0x42. The canonical BAL demotes such a no-op write to a storage_reads entry. The BAL is corrupted into exactly the shape a builder without no-op demotion would emit: the raw write recorded as a storage_changes entry (post_value == pre-tx value) and the read dropped.

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
def test_bal_invalid_noop_storage_change(
    blockchain_test: BlockchainTestFiller,
    pre: Alloc,
) -> None:
    """
    Test that clients reject a BAL storage change whose post-value equals
    the value already present at the start of the transaction.

    Oracle performs a round-trip write: SSTORE(0, 0x42) with slot 0
    already at 0x42. The canonical BAL demotes such a no-op write to a
    storage_reads entry. The BAL is corrupted into exactly the shape a
    builder without no-op demotion would emit: the raw write recorded as
    a storage_changes entry (post_value == pre-tx value) and the read
    dropped.
    """
    alice = pre.fund_eoa()
    oracle = pre.deploy_contract(code=Op.SSTORE(0, 0x42), storage={0: 0x42})

    tx = Transaction(sender=alice, to=oracle, gas_limit=1_000_000)

    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(
                    remove_storage_reads(oracle),
                    append_storage(
                        address=oracle,
                        slot=0,
                        change=BalStorageChange(
                            block_access_index=1, post_value=0x42
                        ),
                    ),
                ),
            )
        ],
    )

Parametrized Test Cases

This test generates 1 parametrized test case across 1 fork.