test_bal_multiple_balance_changes_same_account()

Documentation for tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists.py::test_bal_multiple_balance_changes_same_account@c74f1a67.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip7928_block_level_access_lists/test_block_access_lists.py::test_bal_multiple_balance_changes_same_account --fork Amsterdam

Ensure BAL correctly tracks multiple balance changes to same account across multiple transactions.

An account that receives funds in TX0 and spends them in TX1 should have TWO balance change entries in the BAL, one for each transaction.

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

def test_bal_multiple_balance_changes_same_account(
    pre: Alloc,
    fork: Fork,
    blockchain_test: BlockchainTestFiller,
) -> None:
    """
    Ensure BAL correctly tracks multiple balance changes to same account
    across multiple transactions.

    An account that receives funds in TX0 and spends them in TX1 should
    have TWO balance change entries in the BAL, one for each transaction.
    """
    alice = pre.fund_eoa()
    bob = pre.fund_eoa(amount=0)
    charlie = pre.fund_eoa(amount=0)

    intrinsic_gas_calculator = fork.transaction_intrinsic_cost_calculator()
    tx_intrinsic_gas = intrinsic_gas_calculator(
        calldata=b"",
        access_list=[],
        recipient_type=RecipientType.EMPTY_ACCOUNT,
        sends_value=True,
    )
    top_frame_state_gas = fork.transaction_top_frame_state_gas(
        sends_value=True,
        recipient_type=RecipientType.EMPTY_ACCOUNT,
    )

    # bob receives funds in tx0, then spends everything in tx1
    gas_price = 10
    expected_gas_used = tx_intrinsic_gas + top_frame_state_gas
    tx1_gas_cost = expected_gas_used * gas_price
    spend_amount = 100
    funding_amount = tx1_gas_cost + spend_amount

    tx0 = Transaction(
        sender=alice,
        to=bob,
        value=funding_amount,
        gas_limit=expected_gas_used,
        gas_price=gas_price,
    )

    tx1 = Transaction(
        sender=bob,
        to=charlie,
        value=spend_amount,
        gas_limit=expected_gas_used,
        gas_price=gas_price,
    )

    bob_balance_after_tx0 = funding_amount
    bob_balance_after_tx1 = 0

    blockchain_test(
        pre=pre,
        blocks=[
            Block(
                txs=[tx0, tx1],
                expected_block_access_list=BlockAccessListExpectation(
                    account_expectations={
                        alice: BalAccountExpectation(
                            nonce_changes=[
                                BalNonceChange(
                                    block_access_index=1, post_nonce=1
                                )
                            ],
                        ),
                        bob: BalAccountExpectation(
                            nonce_changes=[
                                BalNonceChange(
                                    block_access_index=2, post_nonce=1
                                )
                            ],
                            balance_changes=[
                                BalBalanceChange(
                                    block_access_index=1,
                                    post_balance=bob_balance_after_tx0,
                                ),
                                BalBalanceChange(
                                    block_access_index=2,
                                    post_balance=bob_balance_after_tx1,
                                ),
                            ],
                        ),
                        charlie: BalAccountExpectation(
                            balance_changes=[
                                BalBalanceChange(
                                    block_access_index=2,
                                    post_balance=spend_amount,
                                )
                            ],
                        ),
                    }
                ),
            )
        ],
        post={
            bob: Account(nonce=1, balance=bob_balance_after_tx1),
            charlie: Account(balance=spend_amount),
        },
    )

Parametrized Test Cases

This test generates 1 parametrized test case across 1 fork.