invalid developer directory '/Applications/Xcode.app/Contents/Developer' code example
Example 1: xcrun: error: invalid active developer path (/Applications/Xcode.app/Contents/Developer),
$ sudo xcode-select -r
$ sudo xcode-select --switch /Library/Developer/CommandLineTools
Example 2: invalid active developer path (/applications/xcode.app/contents/developer)
$ sudo xcode-select -r
$ sudo xcode-select --switch /Library/Developer/CommandLineTool