test_vector_exchange_0x2f()

Documentation for tests/amsterdam/eip8024_dupn_swapn_exchange/test_eip_vectors.py::test_vector_exchange_0x2f@a9abd46e.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip8024_dupn_swapn_exchange/test_eip_vectors.py::test_vector_exchange_0x2f --fork Amsterdam

Test vector: e82f [EXCHANGE 1 19].

EXCHANGE with immediate 0x2f (47 decimal). decode_pair(0x2f) = (1, 19), swaps positions 2 and 20.

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

def test_vector_exchange_0x2f(
    pre: Alloc,
    state_test: StateTestFiller,
) -> None:
    """
    Test vector: e82f [EXCHANGE 1 19].

    EXCHANGE with immediate 0x2f (47 decimal).
    decode_pair(0x2f) = (1, 19), swaps positions 2 and 20.
    """
    sender = pre.fund_eoa()

    # Build stack with 20 items
    # Position 2 and position 20 will be swapped
    code = Bytecode()
    code += Op.PUSH2(0xBBBB)  # Position 20 (bottom, will be swapped)
    for i in range(17):
        code += Op.PUSH2(0x1000 + i)  # Positions 3-19
    code += Op.PUSH2(0xAAAA)  # Position 2 (will be swapped)
    code += Op.PUSH2(0x1111)  # Position 1 (top)

    # EXCHANGE with immediate 0x2f - swaps positions 2 and 20
    # Hex: e8 2f
    code += Op.EXCHANGE[b"\x2f"]

    # Store position 1, 2, and 20 to verify
    code += Op.PUSH1(0) + Op.SSTORE  # Position 1 (top, unchanged)
    code += Op.PUSH1(1) + Op.SSTORE  # Position 2 (was 0xBBBB from pos 20)

    # Pop to get to position 20
    for _ in range(17):
        code += Op.POP

    code += Op.PUSH1(2) + Op.SSTORE  # Position 20 (was 0xAAAA from pos 2)
    code += Op.STOP

    contract_address = pre.deploy_contract(code=code)
    tx = Transaction(to=contract_address, sender=sender)

    # After EXCHANGE[0x2f]: positions 2 and 20 are swapped
    post = {
        contract_address: Account(
            storage={
                0: 0x1111,  # Position 1 unchanged
                1: 0xBBBB,  # Position 2 now has value from position 20
                2: 0xAAAA,  # Position 20 now has value from position 2
            }
        )
    }

    state_test(pre=pre, post=post, tx=tx)

Parametrized Test Cases

This test generates 1 parametrized test case across 1 fork.