Question

When doing Unit Testing, is there a way to tell the [TestClass()] to execute one [TestMethod()] by one? (Instead of Visual Studio to start multiple thread). This would be required for only one or two of my testing classes.

Answer 1

No, there is no way to do this in Visual Studio 2008 using the default tools.

It is possible by adding some … interesting configuration code to the TestInit method. For instance, you could have all of your test classes derive from the following base class.

[TestClass]
public class ExecuteOneAtTimeBase {
  private static object s_mutex = new object();

  [TestInit]
  public void TestInit() {
    Monitor.Enter(s_mutex);
  }

  [TestCleanup]
  public void TestCleanup() {
    Monitor.Exit(s_mutex);
  }
}

All TestMethod instances are bracketed by calls to TestInit and TestCleanup methods. Using the Monitor.Enter/Exit combo you can guarantee that a given unit test method holds the lock for the duration of it’s execution. Therefore multiple threads cannot be running different tests at the same time in a single AppDomain.

There are error cases where this could lead to a deadlock in the testing process. But I think that is probably a minor concern as it’s not production code.