const Owned = artifacts.require('./Owned.sol'); const Proxy = artifacts.require('./Proxy.sol'); contract('Proxy', accounts => { it('Should compile and run when one contract inherits from another', () => Owned.deployed() .then(() => Proxy.deployed()) .then(instance => instance.isOwner.call({ from: accounts[0], })) .then(val => assert.equal(val, true))); });