Overview

Start your own Vyper project

Twig lets you write tests using web3.py and pytest-ethereum against your Vyper smart contracts.

Twig setup

• clone twig repo
• python -m venv venv (note: requires >=python3.6)
• . venv/bin/activate
• pip install -e .

Project setup

Note

contracts/name_registry.vy and tests/test_name_registry.py have been included as examples on how to get started, but are safe to delete.

• create your vyper contract file in contracts/ (i.e. root/contracts/example.vy)
• write your vyper contract test file in tests/ (i.e. root/tests/test_example.py)
• create your contract instance to test against using pytest-ethereum’s `deployer <https://pytest-ethereum.readthedocs.io/en/latest/overview.html#deployer`__. In the following example, the my_contract fixture returns a web3.contract instance for testing against.

@pytest.fixture
def my_contract_package(deployer):
    # returns an ethpm.Package instance loaded with a "my_contract" deployment on the ethpm.Package.w3 instance
    return deployer.deploy("my_contract")

@pytest.fixture
def my_contract(my_contract_package):
    # returns an my_contract web3.contract instance to test against
    return my_contract_package.deployments.get_instance("my_contract")