Check 'ObjCCategoryDecl->getTypeParamList()' for null before trying to use the result.

[rolfbjarne]

Also add a new test.

[rolfbjarne]

Looks like the macOS job failed because the tests crashed?

The active test run was aborted. Reason: Test host process crashed

Could it be that the tests don't use libClangSharp.dylib from the repository, but the published one instead?

[tannergooding]

Could it be that the tests don't use libClangSharp.dylib from the repository, but the published one instead?

Due to the requirements/expense to build libClangSharp, it isn't built as part of CI. It is rather only built on demand and so the test here likely needs to be disabled until after the change goes in and a new set of binaries can be published.