The command pod spec lint fails. I couldn't find a similar question here on SO and on Cocoapod's repo. Full log:
-> GPKit (0.1.1) - ERROR | [iOS] unknown: Encountered an unknown error (757: unexpected token at '2017-08-17 16:12:08.932 simctl[55281:678990] CoreSimulator detected Xcode.app relocation or CoreSimulatorService version change. Framework path (/Applications/Xcode.app/Contents/Developer/Library/PrivateFrameworks/CoreSimulator.framework) and version (375.21) does not match existing job path (/Library/Developer/PrivateFrameworks/CoreSimulator.framework/Versions/A/XPCServices/com.apple.CoreSimulator.CoreSimulatorService.xpc) and version (459.13). Attempting to remove the stale service in order to add the expected version. ') during validation.
Analyzed 1 podspec.
[!] The spec did not pass validation, due to 1 error.
Any solution for this? And why it happens?
For reference, I've managed to solve this problem. I found the answer here: https://stackoverflow.com/a/40258881/3231194
Though the question is about CI.
In short, the solution I got was from Luca, run this:
launchctl remove com.apple.CoreSimulator.CoreSimulatorService || true
As for the explanation what caused the problem, I think it's because I have and run two versions of Xcode. 8.3 and 9.0.
I run into this issue and solved it by changing the Command Line Tools in Xcode (Xcode > Preferences > Locations) as explained here: https://stackoverflow.com/a/41536029/4196117
Bottom line, I was using a different Xcode version for the command line tools than the one I was actively using for my project.
Update: image for reference
来源：https://stackoverflow.com/questions/45730217/pod-spec-lint-coresimulator-detected-xcode-app-relocation-or-coresimulatorservic