Unit testing Anti-patterns catalogue

Answer 1

The Butterfly

You have to test something which contains data that changes all the time, like a structure which contains the current date, and there is no way to nail the result down to a fixed value. The ugly part is that you don't care about this value at all. It just makes your test more complicated without adding any value.

The bat of its wing can cause a hurricane on the other side of the world. -- Edward Lorenz, The Butterfly Effect

Answer 2

Inappropriately Shared Fixture -- Tim Ottinger
Several test cases in the test fixture do not even use or need the setup / teardown. Partly due to developer inertia to create a new test fixture... easier to just add one more test case to the pile

Answer 3

The Flickering Test (Source : Romilly Cocking)

A test which just occasionally fails, not at specific times, and is generally due to race conditions within the test. Typically occurs when testing something that is asynchronous, such as JMS.

Possibly a super set to the 'Wait and See' anti-pattern and 'The Sleeper' anti-pattern.

The build failed, oh well, just run the build again. -- Anonymous Developer

Answer 4

Second Class Citizens - test code isn't as well refactored as production code, containing a lot of duplicated code, making it hard to maintain tests.

Answer 5

The Test With No Name -- Nick Pellow

The test that gets added to reproduce a specific bug in the bug tracker and whose author thinks does not warrant a name of its own. Instead of enhancing an existing, lacking test, a new test is created called testForBUG123.

Two years later, when that test fails, you may need to first try and find BUG-123 in your bug tracker to figure out the test's intent.

Answer 6

The Dead Tree

A test which where a stub was created, but the test wasn't actually written.

I have actually seen this in our production code:

class TD_SomeClass {
  public void testAdd() {
    assertEquals(1+1, 2);
  }
}

I don't even know what to think about that.