TestGetDisplayName is flaky

[jtschuster]

TestGetDisplayName on Linux sometimes fails randomly, then will pass on a retry. It seems to be with formatting generic parameters.

[jtschuster]

I'm running into this issue on Windows too now

[marek-safar]

I believe test are run in random order so there will be some test with side effects causing this

[tlakollo]

I'm able to reproduce the issue in VS only running those tests, no other tests involved. It only happens when running, and the problem disappears when debugging though.

There seems to be a problem with this piece of code https://github.com/dotnet/linker/blob/main/src/linker/Linker/TypeReferenceExtensions.cs#L47-L56

[tlakollo]

I haven't found the source of the error but seems like the test infra has some kind of conflict because there are two different uses of GenericClassMultipleParameters.
https://github.com/dotnet/linker/blob/main/test/Mono.Linker.Tests/Tests/GetDisplayNameTests.cs#L166
https://github.com/dotnet/linker/blob/main/test/Mono.Linker.Tests/Tests/GetDisplayNameTests.cs#L195
Removing one, or renaming one of the methods to something like GenericClassMultipleParameters2 fixes the issue.

[tlakollo]

Went through the test with Sven, we couldn't find the exact place in Cecil for which the race condition happens, but Sven suggested using the NonParallelizable attribute for this test, instead of just avoiding one instance of the problem by changing names