krystal/go-katapult

package buildspec

import (
    "encoding/xml"
    "fmt"
)

type Group struct {
    ID   string `json:"id,omitempty" yaml:"id,omitempty"`
    Name string `json:"name,omitempty" yaml:"name,omitempty"`
}

func (s *Group) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
    x := &xmlGroup{}

    switch {
    case s.ID != "":
        x.Value = s.ID
    case s.Name != "":
        x.By = name
        x.Value = s.Name
    }

    return e.EncodeElement(x, start)
}

func (s *Group) UnmarshalXML(
    d *xml.Decoder,
    start xml.StartElement,
) error {
    x := &xmlGroup{}
    _ = d.DecodeElement(&x, &start)

    v := Group{}

    switch {
    case x.By == "":
        v.ID = x.Value
    case x.By == name:
        v.Name = x.Value
    default:
        return fmt.Errorf(
            `%w: Group by="%s" is not supported`, ErrParseXML, x.By,
        )
    }

    *s = v

    return nil
}

type xmlGroup xmlLookupElem