The Visual Studio Test task on Azure DevOps (fka TFS) has a list of files which are included or excluded.

The default list of test files of Visual Studio Test task

**\*test*.dll
!**\obj\**

The filter above will include everything with test in the filename and will exclude (leading !) the content of the obj folder. The default filter will scan libraries with TestPlatform or TestAdapter for tests as well.

The better approve is to ignore these files as well.

**\*test*.dll
!**\Microsoft.TestPlatform*.dll
!**\Microsoft.VisualStudio.TestPlatform*.dll
!**\NUnit3.TestAdapter.dll
!**\obj\**