asserting only 1 thing in your tests helps your thinking in your domain model more critically

Testing: One assertion per test

asserting only 1 thing in your tests helps your thinking in your domain model more critically

I use multiple assertions per test, and here's why: 1. I'm asserting behavior, not individual lines of code. 2. I've found it rare that there are two different errors in one test (more likely is that one error causes multiple tests to fail). When there are two different errors in one test, I find the second one the next time I run the test. Since 99% of the time, the error(s) are related to some code I just wrote, when I fix that bug, generally I'm green. 3. The more tests, the longer they take to run, especially if database access is involved. The longer tests take to run, the more my TDD cycle is interrupted. 4. I haven't found naming tests to be either that onerous or even that important. For example, say I'm testing GET for a controller. Then that's the name of my test. I don't see the value of repeating the test's assertion in its name. 5. When code scrolls off the to...

Full article: http://blog.jayfields.com/2007/06/testing-one-assertion-p...

Tweets

@delicerubyrails » 12 Sep '12, 11pm
Jay Fields' Thoughts: Testing: One assertion per test: [link]
@josuesantos » 12 Sep '12, 5pm
RT @masihjesus: asserting only 1 thing in your tests helps your thinking in your domain model more critically -> [link] ...
@masihjesus » 12 Sep '12, 5pm
asserting only 1 thing in your tests helps your thinking in your domain model more critically -> [link] [Jay Fields' Thoughts]