test_bal_noop_write_filtering()

Documentation for tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists_cross_index.py::test_bal_noop_write_filtering@892e6d1e.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists_cross_index.py::test_bal_noop_write_filtering --fork Amsterdam

Test that NOOP writes (writing same value or 0 to empty) are filtered.

This verifies that: 1. Writing 0 to an uninitialized slot doesn't appear in BAL 2. Writing the same value to a slot doesn't appear in BAL 3. Only actual changes are tracked

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

def test_bal_noop_write_filtering(
    pre: Alloc,
    blockchain_test: BlockchainTestFiller,
) -> None:
    """
    Test that NOOP writes (writing same value or 0 to empty) are filtered.

    This verifies that:
    1. Writing 0 to an uninitialized slot doesn't appear in BAL
    2. Writing the same value to a slot doesn't appear in BAL
    3. Only actual changes are tracked
    """
    test_code = Bytecode(
        # Write 0 to uninitialized slot 1 (noop)
        Op.SSTORE(1, 0)
        # Write 42 to slot 2
        + Op.SSTORE(2, 42)
        # Write 100 to slot 3 (will be same as pre-state, should be filtered)
        + Op.SSTORE(3, 100)
        # Write 200 to slot 4 (different from pre-state 150, should appear)
        + Op.SSTORE(4, 200)
    )

    sender = pre.fund_eoa()
    test_address = pre.deploy_contract(
        code=test_code,
        storage={3: 100, 4: 150},
    )

    tx = Transaction(
        sender=sender,
        to=test_address,
        gas_limit=100_000,
    )

    # Expected BAL should only show actual changes
    expected_block_access_list = BlockAccessListExpectation(
        account_expectations={
            test_address: BalAccountExpectation(
                storage_changes=[
                    BalStorageSlot(
                        slot=2,
                        slot_changes=[
                            BalStorageChange(
                                block_access_index=1, post_value=42
                            ),
                        ],
                    ),
                    BalStorageSlot(
                        slot=4,
                        slot_changes=[
                            BalStorageChange(
                                block_access_index=1, post_value=200
                            ),
                        ],
                    ),
                ],
            ),
        }
    )

    block = Block(
        txs=[tx],
        expected_block_access_list=expected_block_access_list,
    )

    blockchain_test(
        pre=pre,
        blocks=[block],
        post={
            test_address: Account(storage={2: 42, 3: 100, 4: 200}),
        },
    )

Parametrized Test Cases

This test generates 1 parametrized test case across 1 fork.