"IncludeTestAssemblies" build option doesn't seem to work.

It appeared to me that I would be able to build a test player with the BuildPipeline.BuildPlayer(buildPlayerOptions) API, using one of the buildoptions "IncludeTestAssemblies".

However, the resulting player that is built when specifying "IncludeTestAssemblies" doesn't seem to be a test player build. It behaves the same as a regular build, where the default unity scene is loaded, but no tests are included/run.

Is there something I'm missing? Is the "IncludeTestAssemblies" the same thing as building a test player? Is there a way to build a test player using the BuildPipeline API?

Thanks!