Recently on twitter, Clayton asked for a good book about unit testing without mocks. I don’t believe such a thing can be written, so I’ll try to write it in one blog post. First, here it is in one sentence: Mocks are a smell. They tell you that your code depends on some semi-related part […]
Posts Tagged ‘tdd’
In previous discussions about mock-free unit testing, I’ve shown techniques that I use to eliminate the hard-to-eliminate test doubles. I’ve skipped the simple techniques that I apply all the time. Time to fix that. One technique eliminated about 90% of the test doubles in my code. It’s simple. It’s been around for a long time. […]
I just published an early relese of my Simulated.FileSystem library. This library makes it easier to separate platform concerns out of my models. It works really well with a hexagonal architecture. This library will define a set of ports for common external dependencies, with multiple adapters for each port. The initial release just includes a […]
I recently posted an entry about replacing mocks with Simulators. That one used a Simulator from my running example code. Here’s another example, which may make the concept more clear. This is a file system simulator. I’m building it out as a generic simulator, re-usable across projects. Right now, I’m using it
Previously, I presented mocks as nuclear weapons. Unsurprisingly, commenters wanted examples. I exist to serve. This series will discuss a partly-completed project that I have lying around. The project isn’t perfect. But it will serve to discuss some of the ideas. Since it’s only partly complete, some ideas visible in this stage that would likely become […]
I learned something very useful from Marty Nelson’s blog entry on the proficinecy levels of TDD. It was the first time that I saw a construction which included mock objects as a good thing and that also passed my sniff test. So, I hereby recant: Mocks are no more Evil than are nuclear bombs. I’ve […]
At a talk today, the presenter put the following simple unit test on the screen and asked me what part I would write first.
Recently, I’ve had a large number of discussions around the use of mocks for testing, probably because I keep saying that Mocks are Evil. As a result, I’ve had to articulate how I design systems.