test_dupn_jump_into_immediate_then_execute()

Documentation for tests/amsterdam/eip8024_dupn_swapn_exchange/test_dupn.py::test_dupn_jump_into_immediate_then_execute@26332146.

Generate fixtures for these test cases for Amsterdam with:

fill -v tests/amsterdam/eip8024_dupn_swapn_exchange/test_dupn.py::test_dupn_jump_into_immediate_then_execute --fork Amsterdam

Test jumping into a DUPN immediate, then executing a second DUPN.

The jump lands on the first DUPN's 0x5b immediate, a valid JUMPDEST because analysis is unchanged by EIP-8024, and a second DUPN then duplicates the deepest pushed value and stores it over the canary.

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

@EIPChecklist.Opcode.Test.DataPortion.Jump()
def test_dupn_jump_into_immediate_then_execute(
    pre: Alloc,
    state_test: StateTestFiller,
) -> None:
    """
    Test jumping into a DUPN immediate, then executing a second DUPN.

    The jump lands on the first DUPN's 0x5b immediate, a valid JUMPDEST
    because analysis is unchanged by EIP-8024, and a second DUPN then
    duplicates the deepest pushed value and stores it over the canary.
    """
    sender = pre.fund_eoa()

    setup = sum(
        (Op.PUSH1[i] for i in range(Spec.MIN_STACK_INDEX, 0, -1)),
        Bytecode(),
    )
    # The 0x5b landing pad sits 4 bytes past the setup: PUSH1,
    # target, JUMP, then the DUPN opcode byte itself.
    landing_pad = len(setup) + 4

    code = setup
    code += Op.PUSH1(landing_pad) + Op.JUMP
    code += Op.DUPN[b"\x5b"]  # Jumped into, never executed.
    code += Op.SSTORE(
        0,
        Op.DUPN[Spec.MIN_STACK_INDEX],  # Executed after landing.
    )
    code += Op.STOP

    contract_address = pre.deploy_contract(code=code, storage={0: 0xBA5E})

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

    post = {contract_address: Account(storage={0: Spec.MIN_STACK_INDEX})}

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

Parametrized Test Cases

This test generates 1 parametrized test case across 1 fork.