How to install and test Viper programming language?

Question

Viper is a new functional, strongly typed, bounds/overflow-checking, fixed-point-decimal python syntax-based HLL. The repository does not inlcude any documentation yet.

I built and installed pyethereum with python 3.5.2, and running test_parser.py fails with an sha3 assertion.

 viper $ python test_parser.py 
Traceback (most recent call last):
  File "test_parser.py", line 3, in <module>
    from ethereum import tester as t
  File "/usr/lib/python3.5/site-packages/ethereum-1.6.0-py3.5.egg/ethereum/__init__.py", line 8, in <module>
    from . import slogging  # noqa
  File "/usr/lib/python3.5/site-packages/ethereum-1.6.0-py3.5.egg/ethereum/slogging.py", line 6, in <module>
    from ethereum.utils import bcolors, isnumeric
  File "/usr/lib/python3.5/site-packages/ethereum-1.6.0-py3.5.egg/ethereum/utils.py", line 125, in <module>
    assert encode_hex(sha3(b'')) == b'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470'
AssertionError

What are the requirements to run and install it? And how to do so? I'm assuming it's just using the incorrect sha3() method.

Answer 1

You need to install the latest pyethereum; I just uploaded it as pyethereum 1.3.7, or from the state_revamp branch. That should also automatically install the latest pyrlp, which has one compatibility fix; if it doesn't then you can install it yourself from http://github.com/ethereum/pyrlp.

If you don't do this, then there are going to be a few bugs that you'll run into, the sha3 assertion being one of them, that have to do with py3 compatibility; the latest pyethereum fixes most of them.