Xunit - disable parallelism in few tests of full set

Question

I have about 100 selenium tests to run, but 2 of them cannot be run in parallel

Is it possible to disable parallelism only for those 2 tests, using xUnit?

(those 2 test cannot be parallel, because they need to simulate keyboard clicking -> so I would lose input focus using parallel execution)

Best scenario that I am looking for:

Add some attribute to 2 tests that will disable parallelism for them. Then in tests executions 98 tests will be running with 16 threads, and two remaining tests will be executed at the end using 1 thread.

I know that one of the solutions can be something like this:

• add 'Parallel' and 'NonParallel' categories for tests
• with xunit.console run only 'Parallel' category with parameter maxthread=16.
• after that run 'NonParallel' category with parameter maxthread=1
• And after all of that merge xunit reports into one.

But is not fitting my needs, and I wonder if I can run tests in a scenario like I describe in "best scenario"

P.S. If the is no solution for that, can I find something like that in nunit?

Answer 1

While Diver answer is correct it doesn't show how exactly to achieve this.

1. Create new special class to establish test collection, something like this:

[CollectionDefinition(nameof(SystemTestCollectionDefinition), DisableParallelization = true)]
public class SystemTestCollectionDefinition { }

2. Now you can assign the same Collection name to all tests needed to disable parallelization. In my case I just added an attribute on the class which is base for all system tests:

[Collection(nameof(SystemTestCollectionDefinition))]
public class BaseSystemTest { ... }

Now all tests within Collection will be executed in sequence.

Source: https://github.com/xunit/xunit/issues/1999