lopt

lopt is a utility package that can generate mock Solidity contracts in the form of fakes and mocks.

lopt is based in @eth-optimism/smock, sinon and sinon-chai.

Some benefits of using lopt:

• Test syntax is easy to understand, just like sinon-chai
• Supports both chai expect and should syntax
• Fully typed objects, that will extend your contract functions when using typechain (highly recommended)
• Mock and assert contract calls, without the need of even deploying it by using fakes
• If you need your contract logic, just wrap it in a mock and start asserting calls or changing behaviour
• Fully tested library

Documentation

Documentation is available here.

Installation

You can easily install lopt via npm:

npm install --save-dev @defi-wonderland/lopt

Or via yarn:

yarn add --dev @defi-wonderland/lopt

How to use

...
import { FakeContract, lopt } from '@defi-wonderland/lopt';

chai.should(); // if you like should syntax
chai.use(lopt.matchers);

describe('MyContract', () => {
    let myContractFake: FakeContract<MyContract>;

    beforeEach(async () => {
        ...
        myContractFake = await lopt.fake<MyContract>('MyContract');
    });

    it('some test', () => {
        ...
        myContractFake.bark.atCall(0).should.be.calledWith('Hello World');
    });
});

Why the name lopt?

Loki's alternative name is Lopt, and Loki was obviously taken.

Loki is the God of Mischief, a trickster, and the purpose of mocking libraries is basically to trick the tests.