For the record, when testing against a development network like ganache or geth --dev you need to use openzeppelin-test-helpers
as shown below.
const { singletons } = require('openzeppelin-test-helpers');
contract('ERC777', function (accounts) {
before(async function () {
const funder = accounts[0]; // account that will be used to fund the deployment
await singletons.ERC1820Registry(funder);
});
it(...your test here...);
});