Code review comment for lp:~vanvugt/mir/fix-compositor-lag

> Alan,
>
> I understand. Aside from longer execution times, it creates the risk of
> spurious failures. On the other hand, testing code in its "natural
> environment" without mocking (where you can) is arguably better practice.

At the risk of straying off the topic of this MP...

Unit tests are about testing code in isolation. That is, with test doubles to replace its "natural environment".

It is best practice to have tests at unit, integration and system level.

> Also, the test in question was already timing-dependent.

Already noted. ;)