Are you saying that the definition of an adequate test setup is one that will necessarily catch any possible race conditions?
That sounds like a necessary idea if you're building real-time embedded systems for aircraft operation or something, but for a lot of applications, developing a test harness to that standard would take considerably more time and effort than building out the actual product.
The problem wasn't a race condition, it was an improperly scoped variable. If a different variable name had been used, the failure would have been easy to identify. Testing for the result of something improper wouldn't be appropriate here, either.
But, if the environment is such that it is easy to manifest this condition, I would argue that such a test setup should definitely be considered, given the potential for failure.
That sounds like a necessary idea if you're building real-time embedded systems for aircraft operation or something, but for a lot of applications, developing a test harness to that standard would take considerably more time and effort than building out the actual product.