Appendix B. xUnit command-line options
Because of the way the .NET CLI works, it isn’t obvious that it’s possible to specify command-line options when running tests. If you execute dotnet test -?, you’ll only see the help for the dotnet test command. The -? is picked up first by .NET CLI instead of being passed to the xUnit entry point.
To see the command-line options for xUnit, you have to look at the code. I’ve included it here for reference.