[bjackman]

> The client stub is a concrete final class. It can't be mocked in tests.

I believe this is deliberate, you are supposed to substitute a fake server. This is superior in theory since you have much less scope to get error reporting wrong (since errors actually go across a gRPC transport during the test).

Of course.. at least with C++, there is no well-lit-path for actually _doing_ that, which seems bonkers. In my case I had to write a bunch of undocumented boilerplate to make this happen.

IIUC for Stubby (Google's internal precursor to gRPC) those kinda bizarre ergonomic issues are solved.

[Degorath]

Stubby calls (at least in Java) just use something called a GenericServiceMocker which is akin to a more specialised mockito.