Enable parallel feature in NUnit

The simplest way to activate the parallel feature in NUnit is by doing so at an assembly level.

Open your AssemblyInfo.cs file and add the following line:

[assembly: Parallelizable(ParallelScope.Fixtures)]

The above line of code will make all fixture classes to run in parallel.

--

If don't want to run in parallel, then you could use the ParallelScope.None on the particular class or test.

Here is an example,

[TestFixture]
[Parallelizable(ParallelScope.None)]
public class TestFixture3
{
    // ...
}