Trying to update from Xcode 11 GM to 11.1 always fail.
I tried moving /Applications/Xcode.app first... nothing works
This is my commerce log:
2019-10-08 12:29:08+01 leviathan installd[556]: PackageKit: Install Failed: Error Domain=PKInstallErrorDomain Code=501 "The package is attempting to install content to the system volume." UserInfo={NSLocalizedDescription=The package is attempting to install content to the system volume.} {
Always working workaround (Manual download)
Download the xip file from here
Also:
Latest Release version (Xcode 11.2.1)
or
Latest Beta version (Xcode 11.3 Beta)
or
Any version you need. And all other downloadable contents
Then extract and move it where you like. This has so many benefits comparing to appstore update. (like the ability to resume download, not replacing the old one, not wasting hidden directories and etc.)
Note that you should use safari to download it.
Apple suggested workaround (Force App Store to redownload)
Since This is Known Issues
Xcode may fail to update from the Mac App Store after updating to macOS Catalina. (56061273)
Apple suggest this:
To trigger a new download you can delete the existing Xcode.app or temporarily change the file extension so it is no longer visible to the App Store.
Found a solution.
The problem was that when the GM version came out I renamed it Xcode.app to Xcode 10.app and Xcode beta.app to Xcode.app
App Store couldn't update Xcode then. I had rename Xcode 10.app back to Xcode.app and the update worked.
来源：https://stackoverflow.com/questions/58285784/cant-update-xcode-11