I have pod framework X that has a podspec and it has a dependency on a Swift package. The Swift package has been successfully added to the workspace of framework X (by simply dragging and dropping the folder to create the reference) and can be used for development of the framework.
The part that's a problem is finding a way to define that dependency on the package within the podspec so that when the pod is installed the swift package gets imported along with the framework.
Using source_files doesn't seem to be working:
s.source_files = 'SwiftPackage/*', ...