Skip to content

test_modexp_fork_transition()

Documentation for tests/osaka/eip7883_modexp_gas_increase/test_modexp_thresholds_transition.py::test_modexp_fork_transition@21507778.

Generate fixtures for these test cases for Osaka with:

fill -v tests/osaka/eip7883_modexp_gas_increase/test_modexp_thresholds_transition.py::test_modexp_fork_transition --fork Osaka

Test ModExp gas cost transition from EIP-7883 before and after the Osaka hard fork.

Source code in tests/osaka/eip7883_modexp_gas_increase/test_modexp_thresholds_transition.py
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
@pytest.mark.parametrize(
    "modexp_input,modexp_expected,gas_old,gas_new",
    [
        pytest.param(Spec.modexp_input, Spec.modexp_expected, 200, 1200),
    ],
    ids=[""],
)
@EIPChecklist.GasCostChanges.Test.ForkTransition.Before()
@EIPChecklist.GasCostChanges.Test.ForkTransition.After()
@EIPChecklist.Precompile.Test.ForkTransition.After.Warm()
@EIPChecklist.GasCostChanges.Test.ForkTransition.Before()
@EIPChecklist.GasCostChanges.Test.ForkTransition.After()
def test_modexp_fork_transition(
    blockchain_test: BlockchainTestFiller,
    pre: Alloc,
    env: Environment,
    fork: TransitionFork,
    gas_old: int,
    gas_new: int,
    modexp_input: ModExpInput,
    modexp_expected: bytes,
) -> None:
    """
    Test ModExp gas cost transition from EIP-7883 before and after the Osaka
    hard fork.
    """

    def generate_code(fork: Fork) -> Bytecode:
        call_code = Op.CALL(
            address=Spec.MODEXP_ADDRESS,
            args_size=Op.CALLDATASIZE,
        )

        extra_gas = (
            Op.CALL(
                address=Spec.MODEXP_ADDRESS,
                args_size=Op.CALLDATASIZE,
                address_warm=True,
            ).gas_cost(fork.transitions_to())
            + Op.GAS.gas_cost(
                fork.transitions_to()
            )  # second GAS in measurement
        )
        code = (
            Op.CALLDATACOPY(dest_offset=0, offset=0, size=Op.CALLDATASIZE)
            + Op.GAS  # [gas_start]
            + call_code  # [gas_start, call_result]
            + Op.GAS  # [gas_start, call_result, gas_end]
            + Op.SWAP1  # [gas_start, gas_end, call_result]
            + Op.POP  # [gas_start, gas_end]
            + Op.PUSH2[extra_gas]  # [gas_start, gas_end, extra_gas]
            + Op.ADD  # [gas_start, gas_end + extra_gas]
            + Op.SWAP1  # [gas_end + extra_gas, gas_start]
            + Op.SUB  # [gas_start - (gas_end + extra_gas)]
            + Op.TIMESTAMP  # [gas_start - (gas_end + extra_gas), TIMESTAMP]
            + Op.SSTORE  # []
        )

        # Verification the precompile call result
        code += Op.RETURNDATACOPY(
            dest_offset=0, offset=0, size=Op.RETURNDATASIZE()
        ) + Op.SSTORE(
            Op.AND(Op.TIMESTAMP, 0xFF),
            Op.SHA3(0, Op.RETURNDATASIZE()),
        )
        return code

    def calc_tx_gas_limit(fork: Fork) -> int:
        tx_gas_limit_cap = fork.transaction_gas_limit_cap() or env.gas_limit
        return tx_gas_limit_cap

    timestamps = [14_999, 15_000, 15_001]
    contracts = [
        pre.deploy_contract(generate_code(fork.fork_at(timestamp=t)))
        for t in timestamps
    ]
    gas_values = [gas_old, gas_new, gas_new]

    blocks = [
        Block(
            timestamp=ts,
            txs=[
                Transaction(
                    to=contract,
                    data=modexp_input,
                    sender=pre.fund_eoa(),
                    gas_limit=calc_tx_gas_limit(fork.fork_at(timestamp=ts)),
                )
            ],
        )
        for ts, contract in zip(timestamps, contracts, strict=False)
    ]

    post = {
        contract: Account(
            storage={ts: gas, ts & 0xFF: keccak256(bytes(modexp_expected))}
        )
        for contract, ts, gas in zip(
            contracts, timestamps, gas_values, strict=False
        )
    }

    blockchain_test(
        pre=pre,
        blocks=blocks,
        post=post,
    )

Parametrized Test Cases

This test generates 1 parametrized test case across 1 fork.