Xcode 打开playground文件的时候提示-Unable to find execution service for selected run destination

解决办法：

step 1: 关闭Xcode (快捷键cmd + q)

step 2:在terminal里面运行如下语句

rm -rf ~/Library/Developer/CoreSimulator/Devices
killall -9 com.apple.CoreSimulator.CoreSimulatorService

参考链接：

https://blog.csdn.net/youtk21ai/article/details/50259253

https://forums.developer.apple.com/thread/23874