New create Cloudstorage storage, err := New(ctx,cred) .

MockBucketNotExists let IsBucketExists return exists .

MockError let function error .

MockFileNotExists let IsFileExists return exists .

MockSuccess let function return nil .

Implementation is Cloudstorage implementation .

Gstorage is google cloud storage toolkit before use this toolkit you need verify domain owner ship, please add service account in gclould.key to https://www.google.com/webmasters/verification .

Mock define key test flag .

ShouldDeleteFile use in SyncDir to determine a file should be delete .