Add Bigger/Lower to Package to allow version comparison easier

pkg/package/package.go

@@ -57,6 +57,7 @@ type Package interface {
 	GetVersion() string
 	RequiresContains(PackageDatabase, Package) (bool, error)
 	Matches(m Package) bool
+	Bigger(m Package) bool
 
 	AddUse(use string)
 	RemoveUse(use string)
@@ -254,13 +255,19 @@ func (p *DefaultPackage) Clone() Package {
 	copier.Copy(&new, &p)
 	return new
 }
-
 func (p *DefaultPackage) Matches(m Package) bool {
 	if p.GetFingerPrint() == m.GetFingerPrint() {
 		return true
 	}
 	return false
 }
+func (p *DefaultPackage) Bigger(m Package) bool {
+	low := Lower([]Package{p, m})
+	if low.Matches(m) {
+		return true
+	}
+	return false
+}
 
 func (p *DefaultPackage) Expand(definitiondb PackageDatabase) ([]Package, error) {
 	var versionsInWorld []Package
@@ -332,7 +339,29 @@ func (pack *DefaultPackage) RequiresContains(definitiondb PackageDatabase, s Pac
 
 	return false, nil
 }
+func Lower(set []Package) Package {
+	var versionsMap map[string]Package = make(map[string]Package)
+	if len(set) == 0 {
+		panic("Best needs a list with elements")
+	}
 
+	versionsRaw := []string{}
+	for _, p := range set {
+		versionsRaw = append(versionsRaw, p.GetVersion())
+		versionsMap[p.GetVersion()] = p
+	}
+
+	versions := make([]*version.Version, len(versionsRaw))
+	for i, raw := range versionsRaw {
+		v, _ := version.NewVersion(raw)
+		versions[i] = v
+	}
+
+	// After this, the versions are properly sorted
+	sort.Sort(version.Collection(versions))
+
+	return versionsMap[versions[0].Original()]
+}
 func Best(set []Package) Package {
 	var versionsMap map[string]Package = make(map[string]Package)
 	if len(set) == 0 {