Unit tests have been added to the incoming transactions controller to
ensure that block updates are correctly resulting in state updates when
incoming transactions are enabled. All other events that trigger state
updates are tested as well.
The tests were written to be minimally dependent upon implementation
details of the controller itself. `nock` was used to mock the API
response from Etherscan. Each event is triggered asynchronously by
`sinon`, as in production they are likely only triggered
asynchronously.
This was extracted from #9583
This PR includes a new `wait-until-called` module meant to help with
writing asynchronous tests. It allows you to wait until a stub has been
called.
Mark Stacey