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It seems that in many unit tests, the values that parameterize the test are either baked in to the test themselves, or declared in a predetermined way. For example, here is a test taken from nUnit's unit tests (EqualsFixture.cs): [Test] public void Int() { int val = 1; int expected = val; int actual = val; Assert.IsTrue(expected == actual); Assert.AreEqual(expected, actual); } This has the advantage of being deterministic; if you run the test once, and it fails, it will continue to fail until the code is fixed. However, you end up only testing a limited set of values. I can't help but feel like this is a waste, though; the exact same test is probably run with the exact same parameters hundreds if not thousands of times across the life of a project. What about randomizing as much input to all unit tests as possible, so that each run has a shot of revealing something new? In the previous example, perhaps: [Test] public void Int() { Random rnd = new Random(); int val = rnd.Next(); int expected = val; int actual = val; Console.WriteLine("val is {0}", val); Assert.IsTrue(expected == actual); Assert.AreEqual(expected, actual); } (If the code expected a string, perhaps a random string known to be valid for the particular function could be used each time) The benefit would be that the more times you run a test, the much larger set of possible values you know it can handle correctly. Is this useful? Evil? Are there drawbacks to this? Am I completely missing the point of unit testing? Thank you for your thoughts.

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