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Comment by sethammons | Hacker News Reader

This is where I divert. You just hard coded seconds into your test. Now your tests that cover this must take seconds to finish; thankfully you were not testing hours or days!

My last shop was a Go shop and one test I think shows this off was an SMTP server and we needed to test the timeouts at different states. The test spun up half a dozen instances of the server, got each into the right smtp state and verified timeouts in under 10ms.

The environment that set the timeout would either be "timeout_ms=500" or "timeout=500ms" (or whatever). This is where you handle that :)

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Not sure I fully understood your objection, but the reason I specified seconds is because I presumed the setConnectTimeout to be part of the default HTTP library, which likely doesn't adhere to the same conventions, and that it expected seconds (which seem to be the usual for http libraries as far as I can tell).

Of course if the setConnectTimeout method was part of the same application you could just pass the timeout directly, but at the boundary of your application you're still going to have to specify at some point which unit you want.

If you're testing things with timeouts it's often a good practice to mock out the system clock anyway. That allows testing your timeouts to be nearly instantaneous and also catches edge cases like the clock not moving forward, having a low resolution, moving backward, ... deterministically.

The test could simply mock the default value to something reasonable like '.1 seconds' and test that duration instead, so I don't think this is a real problem.

This is actually revealing a different problem: the system clock as an implicit dependency. YMMV depending on support of underlying libraries, but I will typically make the clock an explicit dependency of a struct/function. In Go, usually it’s a struct field `now func() time.Time` with a default value of `time.Now`.

Many timeout functions take seconds as a floating point. So you could time out on 0.05 seconds (5 milis). But now the code is clear and less prone to bugs.

In Go, you don't pass a float, you pass a duration

Which is unitless, hence there is no problem. `time.Duration.Seconds()` returns a floating point.

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