If filepath.Walk gets an error from os.Lstat, it invokes its callback with a nil os.FileInfo and the error. This will cause findZTests to panic because its filepath.Walk callback does not check for an error before calling os.FileInfo.IsDir. Fix by checking for an error in the callback.
If filepath.Walk gets an error from os.Lstat, it invokes its callback with a nil os.FileInfo and the error. This will cause findZTests to panic because its filepath.Walk callback does not check for an error before calling os.FileInfo.IsDir. Fix by checking for an error in the callback.