38. Testing Vyper contracts with Titanoboa

Titanoboa is a Vyper-focused testing/interpreter framework that lets you deploy and call Vyper contracts directly from Python, with full tracebacks pointing back into your Vyper source — much friendlier than decoding raw revert bytes.

import boa

source = '''
counter: public(uint256)

@external
def increment():
    self.counter += 1
'''

contract = boa.loads(source)
contract.increment()
assert contract.counter() == 1

Because it runs an interpreter rather than only the compiled EVM bytecode, Titanoboa can also give richer debugging output (line-level stack traces) during test failures.

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