Downloaded and unarchived Building a Great Mac App with SwiftUI Set the team in Signing & Capabilities Built project Opened a view file with a preview provider -- e.g., GardenApp/Navigation/ContentView.swift Pressed "Resume" in preview pane. Result: "Cannot preview in this file -- Failed to launch Garden App.app" Diagnostic dialog says: FailedToLaunchError: Failed to launch Garden App.app /Users/pf/Library/Developer/Xcode/DerivedData/Session1-epkltatcrbtmzhclsybsiwjohcvx/Build/Intermediates.noindex/Previews/Garden App Start/Products/Debug/Garden App.app ================================== | HumanReadableNSError: The operation couldn’t be completed. (OSStatus error -10825.) | | NSOSStatusErrorDomain (-10825): | ==_LSFunction: _LSOpenStuffCallLocal | ==_LSLine: 3762 Xcode: Version 13.0 beta (13A5154h) Big Sur: 11.4 (20F71) Something's broken, but I don't know what. (Not a seasoned Xcode user.)

While coding, Xcode Version 15.4 (15F31d) is consistently breaking builds by changing both struct and class declarations in areas of code other than where I'm currently editing. Suddenly, code that was compiling a minute ago breaks with multiple "Type 'Xxxx' has no member 'getYyyy'. For example, I'm writing code in a subclass, and suddenly calls to the superclass's methods are unrecognized by the compiler (e.g., "Type 'MeetInfoSheetReader' has no member 'getDateValue'"). Command-click on the method name takes me to the method in the superclass, and nothing is wrong at that point: I have the correct method signature, yet the code doesn't compile. I scroll up to the class declaration only to find that Xcode has changed "class" to "enum". This can happen regardless of whether the superclass or the reference struct is in the same or a different file. Also, this happens frequently, and it's not because I have bouts of narcolepsy and changed class or struct to enum while out. My dog doesn't even get near the laptop while I'm away from it, and I don't have a cat who types let alone a cat. Because I cannot associate this aggravating Xcode behavior with any particular thing I'm doing (e.g., name refactoring a variable or class name, deleting commented sections of exploratory code, or anything else) I'm sure that if I file a bug with the Feedback Assistant (a really ****** bug reporting system), it will be marked closed without the slightest bit of interest in exploring the problem. Hopefully someone else has seen this behavior and has a solution. Because it's really counterproductive.