Hopefully the code is what you'd expect.
The previous example creates a mock Runnable in an expect-let, expects the
runmethod to be run, and then calls the run method of the mock. This test is worthless in a real world context, but it's the simplest way to demonstrate the syntax for creating a mock & specifying the interaction.
mockfunction defined in erajure, a minimal wrapper around mockito. All of the "times" arguments are the same as what's available for function interaction tests, examples can be found here.