Hello.
I could wrong, but it seems NSWorkspace.open cannot open xcodeproj.
When I try to do so in my sandboxed App, the App would hang the thread, causing NSWorkspace.open not responsive in the following calls. If called on the @main thread, then bad luck, it would cause dead lock.
Callings this function on a normal file, such as .txt, or in a Command line Tool works perfectly. Is there anything obvious that I missed?
I have permissions to read/write the files, as indicated by url.resourceValues(forKeys: [.isWritableKey]).isWritable.