func()

in pkg/cloud/api/resource.go [62:120]

• 45 lines of code
• 23 McCabe index (conditional complexity)

func (obj *resource[GA, Alpha, Beta]) Diff(other Resource[GA, Alpha, Beta]) (*DiffResult, error) {
	switch {
	// Comparisons between the same versions don't need conversions.
	//
	// cmp(GA, GA)
	case obj.Version() == meta.VersionGA && other.Version() == meta.VersionGA:
		aObj, _ := obj.ToGA()
		bObj, _ := other.ToGA()
		return diff(aObj, bObj, obj.x.typeTrait.FieldTraits(meta.VersionGA))
	// cmp(Alpha, Alpha)
	case obj.Version() == meta.VersionAlpha && other.Version() == meta.VersionAlpha:
		aObj, _ := obj.ToAlpha()
		bObj, _ := other.ToAlpha()
		return diff(aObj, bObj, obj.x.typeTrait.FieldTraits(meta.VersionAlpha))
	// cmp(Beta, Beta)
	case obj.Version() == meta.VersionBeta && other.Version() == meta.VersionBeta:
		aObj, _ := obj.ToBeta()
		bObj, _ := other.ToBeta()
		return diff(aObj, bObj, obj.x.typeTrait.FieldTraits(meta.VersionBeta))

	// GA => Alpha, GA => Beta should be safe and supported with a conversion.
	//
	// cmp(GA, Alpha), cmp(Alpha, GA): convert to Alpha, then compare.
	case obj.Version() == meta.VersionGA && other.Version() == meta.VersionAlpha:
		fallthrough
	case obj.Version() == meta.VersionAlpha && other.Version() == meta.VersionGA:
		aObj, err := obj.ToAlpha()
		if err != nil {
			return nil, fmt.Errorf("Resource.Diff: %s", err)
		}
		bObj, err := other.ToAlpha()
		if err != nil {
			return nil, fmt.Errorf("Resource.Diff: %s", err)
		}
		return diff(aObj, bObj, obj.x.typeTrait.FieldTraits(meta.VersionAlpha))
	// cmp(GA, Beta), cmp(Beta, GA): convert to Beta, then compare.
	case obj.Version() == meta.VersionGA && other.Version() == meta.VersionBeta:
		fallthrough
	case obj.Version() == meta.VersionBeta && other.Version() == meta.VersionGA:
		aObj, err := obj.ToBeta()
		if err != nil {
			return nil, fmt.Errorf("Resource.Diff: %s", err)
		}
		bObj, err := other.ToBeta()
		if err != nil {
			return nil, fmt.Errorf("Resource.Diff: %s", err)
		}
		return diff(aObj, bObj, obj.x.typeTrait.FieldTraits(meta.VersionBeta))

	// Comparison between Alpha/Beta is not supported right now. This probably
	// can work with some manual conversion logic.
	case obj.Version() == meta.VersionAlpha && other.Version() == meta.VersionBeta:
		return nil, fmt.Errorf("cross alpha/beta diff not supported")
	case obj.Version() == meta.VersionBeta && other.Version() == meta.VersionAlpha:
		return nil, fmt.Errorf("cross beta/alpha diff not supported")
	}

	return nil, fmt.Errorf("invalid versions (got a.Version=%s, b.Version=%s)", obj.Version(), other.Version())
}