Simple Method for starting multi-thread parallel processing in unit test

In unit tests, you often need to perform simple verification on [ThreadStatic] and processing of some mutex environments. There are many ways to start parallel processing. Here is a simple method.

 

Code Static void Parallel (params ThreadStart [] actions)
{
List <Thread> threads = actions. Select (a => new Thread (a). ToList ();
Threads. ForEach (t => t. Start ());
Threads. ForEach (t => t. Join ());
}

The following is a complete example:

Code Using System. Collections. Generic;
Using System. Linq;

Using System. Threading;
Using System. Diagnostics;
Using Microsoft. VisualStudio. TestTools. UnitTesting;

Namespace VisionLogic. Training. ParallelUnitTesting
{
[TestClass]
Public class ObjectWithIdentifierFixture
{
[TestMethod]
Public void TestPerThreadExecution ()
{
Parallel (
Delegate {ThreadInternalA ();},
Delegate {ThreadInternalB ();}
);
}

Void ThreadInternalA ()
{
WriteLine ("a1 ");
Thread. Sleep (2000 );
WriteLine ("a2 ");
}

Void ThreadInternalB ()
{
WriteLine ("b1 ");
Thread. Sleep (1000 );
WriteLine ("b2 ");
}

# Region Helper Methods

Static void WriteLine (string message)
{
Trace. WriteLine (string. Format ("thread {0 }:{ 1}", Thread. CurrentThread. ManagedThreadId, message ));
}

Static void Parallel (params ThreadStart [] actions)
{
List <Thread> threads = actions. Select (a => new Thread (a). ToList ();
Threads. ForEach (t => t. Start ());
Threads. ForEach (t => t. Join ());
}

# Endregion
}
}

The execution result is shown in the Output window as follows: (TestDriven. NET is used here)

------ Test started: Assembly: ParallelUnitTesting. dll ------

Thread 13: a1
Thread 14: b1
Thread 14: b2
Thread 13: a2

1 passed, 0 failed, 0 skipped, took 2.86 seconds (Ad hoc ).

Note: delegate. BeginInvoke is not used here because it may use a thread pool, so that multiple threads are not actually started.