code: func (d *DotGit) Ref(name plumbing.ReferenceName) (*plumbing.Reference, error) {
  	ref, err := d.readReferenceFile(".", name.String())
  	if err == nil {
  		return ref, nil
  	}
  
  	return d.packedRef(name)
  }
docs: // Ref returns the reference for a given reference name.