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Comment by glenjamin | Hacker News Reader

Some time ago I stopped debating the definition of "unit" in testing, and instead started focusing on whether my tests were fast, reliable, and provided a useful signal about the health of the system when they failed. I've been much happier since then.

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This is what Working Effectively with Legacy Code says:

Here are qualities of good unit tests:

  1. They run fast.

  2. They help us localize problems.

A unit test that takes 1/10th of a second to run is a slow unit test.

Nice joke, it takes longer to upload firmware with the unit test suite than that.

The test that is too short is most likely not being thorough enough, or the functionality it tests is so simplistic the test likely brings no value.

What about integration or end to end tests?

That's surprising to me, because the author of that book recently re-advertised his long post about a hard-line definition of a "unit" test

https://www.artima.com/weblogs/viewpost.jsp?thread=126923

I think the properties you list are good ones, but if you drop the word unit from your post the advice is just as good and you can't get mired in ontological discussions

This is the sticking point I've found. The definition of "unit" is different depending on who I talk to.

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