Added string-sorting support for relaxed-versions

Author: cmaglie

relaxed_version.go

@@ -103,3 +103,18 @@ func (v *RelaxedVersion) CompatibleWith(u *RelaxedVersion) bool {
 	}
 	return v.Equal(u)
 }
+
+// SortableString returns the version encoded as a string that when compared
+// with alphanumeric ordering it respects the original semver ordering:
+//
+//	(v1.SortableString() < v2.SortableString()) == v1.LessThan(v2)
+//	cmp.Compare[string](v1.SortableString(), v2.SortableString()) == v1.CompareTo(v2)
+//
+// This may turn out useful when the version is saved in a database or is
+// introduced in a system that doesn't support semver ordering.
+func (v *RelaxedVersion) SortableString() string {
+	if v.version != nil {
+		return ";" + v.version.SortableString()
+	}
+	return ":" + string(v.customversion)
+}

relaxed_version_test.go

@@ -7,6 +7,7 @@
 package semver
 
 import (
+	"cmp"
 	"fmt"
 	"testing"
 
@@ -17,47 +18,93 @@ func TestRelaxedVersionComparator(t *testing.T) {
 	sign := map[int]string{1: ">", 0: "=", -1: "<"}
 	ascending := func(list ...*RelaxedVersion) {
 		for i := range list[0 : len(list)-1] {
-			a := list[i]
-			b := list[i+1]
-			comp := a.CompareTo(b)
-			fmt.Printf("%s %s %s\n", a, sign[comp], b)
-			require.Equal(t, comp, -1)
-			require.True(t, a.LessThan(b))
-			require.True(t, a.LessThanOrEqual(b))
-			require.False(t, a.Equal(b))
-			require.False(t, a.GreaterThanOrEqual(b))
-			require.False(t, a.GreaterThan(b))
-
-			comp = b.CompareTo(a)
-			fmt.Printf("%s %s %s\n", b, sign[comp], a)
-			require.Equal(t, comp, 1)
-			require.False(t, b.LessThan(a))
-			require.False(t, b.LessThanOrEqual(a))
-			require.False(t, b.Equal(a))
-			require.True(t, b.GreaterThanOrEqual(a))
-			require.True(t, b.GreaterThan(a))
-		}
-	}
-	equal := func(list ...*RelaxedVersion) {
-		for _, a := range list {
-			for _, b := range list {
+			{
+				a := list[i]
+				b := list[i+1]
 				comp := a.CompareTo(b)
 				fmt.Printf("%s %s %s\n", a, sign[comp], b)
-				require.Equal(t, comp, 0)
-				require.False(t, a.LessThan(b))
+				require.Equal(t, comp, -1)
+				require.True(t, a.LessThan(b))
 				require.True(t, a.LessThanOrEqual(b))
-				require.True(t, a.Equal(b))
-				require.True(t, a.GreaterThanOrEqual(b))
+				require.False(t, a.Equal(b))
+				require.False(t, a.GreaterThanOrEqual(b))
 				require.False(t, a.GreaterThan(b))
 
 				comp = b.CompareTo(a)
 				fmt.Printf("%s %s %s\n", b, sign[comp], a)
-				require.Equal(t, comp, 0)
+				require.Equal(t, comp, 1)
 				require.False(t, b.LessThan(a))
-				require.True(t, b.LessThanOrEqual(a))
-				require.True(t, b.Equal(a))
+				require.False(t, b.LessThanOrEqual(a))
+				require.False(t, b.Equal(a))
 				require.True(t, b.GreaterThanOrEqual(a))
-				require.False(t, b.GreaterThan(a))
+				require.True(t, b.GreaterThan(a))
+			}
+			{
+				a := list[i].SortableString()
+				b := list[i+1].SortableString()
+				comp := cmp.Compare(a, b)
+				fmt.Printf("%s %s %s\n", a, sign[comp], b)
+				require.Equal(t, comp, -1)
+				require.True(t, a < b)
+				require.True(t, a <= b)
+				require.False(t, a == b)
+				require.False(t, a >= b)
+				require.False(t, a > b)
+
+				comp = cmp.Compare(b, a)
+				fmt.Printf("%s %s %s\n", b, sign[comp], a)
+				require.Equal(t, comp, 1)
+				require.False(t, b < a)
+				require.False(t, b <= a)
+				require.False(t, b == a)
+				require.True(t, b >= a)
+				require.True(t, b > a)
+			}
+		}
+	}
+	equal := func(list ...*RelaxedVersion) {
+		for _, a := range list {
+			for _, b := range list {
+				{
+					comp := a.CompareTo(b)
+					fmt.Printf("%s %s %s\n", a, sign[comp], b)
+					require.Equal(t, comp, 0)
+					require.False(t, a.LessThan(b))
+					require.True(t, a.LessThanOrEqual(b))
+					require.True(t, a.Equal(b))
+					require.True(t, a.GreaterThanOrEqual(b))
+					require.False(t, a.GreaterThan(b))
+
+					comp = b.CompareTo(a)
+					fmt.Printf("%s %s %s\n", b, sign[comp], a)
+					require.Equal(t, comp, 0)
+					require.False(t, b.LessThan(a))
+					require.True(t, b.LessThanOrEqual(a))
+					require.True(t, b.Equal(a))
+					require.True(t, b.GreaterThanOrEqual(a))
+					require.False(t, b.GreaterThan(a))
+				}
+				{
+					a := a.SortableString()
+					b := b.SortableString()
+					comp := cmp.Compare(a, b)
+					fmt.Printf("%s %s %s\n", a, sign[comp], b)
+					require.Equal(t, comp, 0)
+					require.False(t, a < b)
+					require.True(t, a <= b)
+					require.True(t, a == b)
+					require.True(t, a >= b)
+					require.False(t, a > b)
+
+					comp = cmp.Compare(b, a)
+					fmt.Printf("%s %s %s\n", b, sign[comp], a)
+					require.Equal(t, comp, 0)
+					require.False(t, b < a)
+					require.True(t, b <= a)
+					require.True(t, b == a)
+					require.True(t, b >= a)
+					require.False(t, b > a)
+				}
 			}
 		}
 	}