<PackageReference Include="NUnit" Version="3.8.1" />

ParallelScope

public enum ParallelScope
The ParallelScope enumeration permits specifying the degree to which a test and its descendants may be run in parallel.
All = 257

The test and its descendants may be run in parallel with others at the same level. Valid on classes and methods but not assemblies.

Children = 256

Descendants of the test may be run in parallel with one another. Valid on assemblies and classes but not on methods.

Mask used to extract all the flags that impact descendants of a test and place them in the TestExecutionContext.

Default = 0

No ParallelScope was specified on the test

Fixtures = 512

Descendants of the test down to the level of TestFixtures may be run in parallel with one another. Valid on assemblies and classes but not on methods.

Mask used to extract the flags that apply to the item on which a ParallelizableAttribute has been placed, as opposed to descendants.

None = 2

Test may not be run in parallel with any others. Valid on classes and methods but not assemblies.

Self = 1

The test may be run in parallel with others at the same level. Valid on classes and methods but not assemblies.