c# - Are multiple asserts bad in a unit test? Even if chaining?

Question

Is there anything wrong with checking so many things in this unit test?:

ActualModel = ActualResult.AssertViewRendered()        // check 1
                          .ForView("Index")            // check 2
                          .WithViewData<List<Page>>(); // check 3

CollectionAssert.AreEqual(Expected, ActualModel);      // check 4

The primary goals of this test are to verify the right view is returned (check 2) and it contains the right data (check 4).

Would I gain anything by splitting this into multiple tests? I'm all about doing things right, but I'm not going to split things up if it doesn't have practical value.

I'm pretty new to unit testing, so be gentle.

question from:https://stackoverflow.com/questions/2430429/are-multiple-asserts-bad-in-a-unit-test-even-if-chaining

Answer 1

As others have pointed out, it's best to stick with one assert in each test in order to avoid losing information - if the first assert fails, you don't know whether the later ones would fail also. You have to fix the problem with less information - which might (probably will) be harder.

A very good reference is Roy Osherove's Art of Unit Testing - if you want to get started right with Unit Testing, you could do a lot worse than starting here.