// the schema changes for versions in the range startVer < ver <= endVer
// when endVer is empty this method returns all subdir names that are greater than startVer
func readSchemaDir(fsys fs.FS, dir string, startVer string, endVer string, logger log.Logger) ([]string, error) {
updatetask.go
subDirs, err := fs.ReadDir(fsys, dir)
if err != nil {
return nil, err
}
return nil, fmt.Errorf("directory '%s' contains no subDirs", dir)
}