clock

I have a fair bit of experience writing tests for concurrent code that uses timers on Go. We started with an open source test library ( https://pkg.go.dev/github.com/benbjohnson/clock ). It had a lot of problems. This was many years ago, looks like it's seen some maintenance since so maybe it's better? Then we tried to fix it. Fixed all the obvious bugs but still had a lot of problems using it in practice. It's not enough to just handle the calls without context of who is calling them in concurrent code. Then we switched to using gomock which ended up also being hard to use. It's quite tricky is sort of the bottom line. It's not enough to just create fake time there's a lot more to it.

I recently discovered the joy of abstracting away time. I write a lot of software in Go for work. This library, https://github.com/benbjohnson/clock, provides a Clock interface that can be used for creating either clocks with the same interface as the standard "time" module, or to create a mock clock that increments to the next tick on any and all tickers defined in the app. It really makes unit tests go faster, though it can be tricky to get the code right.