test_eip_vector_end_of_code()

Documentation for tests/amsterdam/eip8024_dupn_swapn_exchange/test_eip_vectors.py::test_eip_vector_end_of_code@8acae1b0.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip8024_dupn_swapn_exchange/test_eip_vectors.py::test_eip_vector_end_of_code --fork Amsterdam

Test EIP-8024 opcodes at end of code (no immediate byte).

When an opcode appears at end of code, code[pc+1] = 0 beyond end of code. - DUPN: decode_single(0) = 145, needs 145 items on stack - SWAPN: decode_single(0) = 145, needs 146 items on stack - EXCHANGE: decode_pair(0) = (9, 16), needs 17 items on stack

Store a marker before the opcode to verify the transaction succeeded, since adding any opcode after would make that opcode byte the immediate.

Source code in tests/amsterdam/eip8024_dupn_swapn_exchange/test_eip_vectors.py

@pytest.mark.parametrize(
    "eip8024_opcode,stack_items",
    [
        pytest.param(Op.DUPN, 145, id="dupn"),
        pytest.param(Op.SWAPN, 146, id="swapn"),
        pytest.param(Op.EXCHANGE, 17, id="exchange"),
    ],
)
def test_eip_vector_end_of_code(
    pre: Alloc,
    state_test: StateTestFiller,
    eip8024_opcode: Op,
    stack_items: int,
) -> None:
    """
    Test EIP-8024 opcodes at end of code (no immediate byte).

    When an opcode appears at end of code, code[pc+1] = 0 beyond end of code.
    - DUPN: decode_single(0) = 145, needs 145 items on stack
    - SWAPN: decode_single(0) = 145, needs 146 items on stack
    - EXCHANGE: decode_pair(0) = (9, 16), needs 17 items on stack

    Store a marker before the opcode to verify the transaction succeeded,
    since adding any opcode after would make that opcode byte the immediate.
    """
    sender = pre.fund_eoa()
    marker_value = 0x42

    code = (
        # store marker for verification
        Op.SSTORE(0, marker_value)
        # push minimum required stack items for the opcode
        + Op.PUSH0 * stack_items
        # end-of-code EIP-8024 opcode
        + eip8024_opcode
    )
    contract_address = pre.deploy_contract(code=code)

    tx = Transaction(to=contract_address, sender=sender)

    # verify marker was stored (tx succeeded)
    post = {contract_address: Account(storage={0: marker_value})}
    state_test(pre=pre, post=post, tx=tx)

Parametrized Test Cases

This test generates 3 parametrized test cases across 1 fork.