RuntimeError - PBXGroup attempted to initialize an object with unknown ISA PBXFileSystemSynchronizedRootGroup from attributes: {"isa"=>"PBXFileSystemSynchronizedRootGroup", "explicitFileTypes"=>{}, "explicitFolders"=>[], "path"=>"AmoveTestTests", "sourceTree"=>"<group>"}
If this ISA was generated by Xcode please file an issue: github.com/CocoaPods/X…
/usr/local/Cellar/cocoapods/1.15.2/libexec/gems/xcodeproj-1.24.0/lib/xcodeproj/project/object.rb:359:in `rescue in object_with_uuid'
解决办法：打开工程 将工程下所有的文件夹逐一右击，选择Convert to Group 重新pod install即可。
