Py evm 1466

[dherykw]

What was wrong?

EIP170 states that the contract size limit was changed to 2**14 + 2**13 which is 24,576 bytes. The following line implementations the constant for EIP170, but it is off by one.

Issue Reference: #1466

How was it fixed?

Contract limit size was changed by @glaksmono, I have improved the tests

• Update the contract limit size to follow EIP170
• Add tests against the contract size limit

To-Do

• Clean up commit history

• Add entry to the release notes

Cute Animal Picture

[dherykw]

I forgot to pull the upstream... my fault.

Now all test passes.

[pipermerriam]

Mock based approaches tend to be problematic. I'd prefer we test this properly using a contract that actually exceeds this limit so that we can see this fail using non-mock/real mechanisms.

[voith]

nothing related to this comment and I agree with piper here, but here's a nice article I found on mocking today written by Ned Batchelder: https://nedbatchelder.com/blog/201908/why_your_mock_doesnt_work.html

[dherykw]

No worries @pipermerriam and @voith, currently I am out of my town with limited connectivity, but next week I will give it another try. It will help me to have a better understanding of the code and help with more complicated task.

[dherykw]

Hello guys,

I am stuck for a while, I am trying to deploy a dummy contract to the chain but I am receiving a huge out of gas error. I have introduced the question on stack exchange:

https://ethereum.stackexchange.com/questions/74091/deploy-contract-in-py-evm?noredirect=1#comment90183_74091

The full "test" code (because I haven introduces the asserts yet) is:

@pytest.mark.parametrize('chain_without_block_validation', [MiningChain, ], indirect=True)
def test_computation_output_size_limit(chain_without_block_validation):
    SENDER_PRIVATE_KEY = keys.PrivateKey(
        decode_hex('0x45a915e4d060149eb4365960e6a7a45f334393093061116b197e3240065ff2d8')
    )

    SENDER = Address(SENDER_PRIVATE_KEY.public_key.to_canonical_address())

    state = chain_without_block_validation.get_vm().state
    state.set_balance(SENDER, 1000)

    vm = chain_without_block_validation.get_vm()
    nonce = vm.state.get_nonce(SENDER)

    vm_tx = vm.create_unsigned_transaction(
        nonce=nonce,
        gas_price=10,
        gas=3138525,
        to=CREATE_CONTRACT_ADDRESS,
        value=0,
        data=b'60606040523415600e57600080fd5b5b603680601c6000396000f30060606040525b600080fd00a165627a7a72305820c9e69aabe54411b89c6b2223932d7349334d3e75c12657355b7ba52c47e4db250029',
    )
    signed_tx = vm_tx.as_signed_transaction(SENDER_PRIVATE_KEY)
    new_block, receipt, c = chain_without_block_validation.apply_transaction(signed_tx)

    print("--------------------------------------------------------")
    print("Computation is error: {}".format(c.is_error))
    if c.is_error:
        print("Computation error: {}".format(c.error))

    print("computation output: {}".format(c.output))
    print("computation output len: {}".format(len(c.output)))

I would appreciate any help :)

[pipermerriam]

@dherykw how did you go about getting that deployment bytecode. My guess is that there's something wrong with it. The error you're receiving is a standard EVM error so it's probably worth you trying to trace the VM execution to figure out why it's trying to expand the memory to such a large size.