compare: Add a string sort benchmark

compare/compare_strings_test.go

@@ -62,3 +62,22 @@ func TestLexicographicSort(t *testing.T) {
 
 	c.Assert(s, qt.DeepEquals, []string{"A", "b", "Ba", "ba", "ba", "Bz"})
 }
+
+func BenchmarkStringSort(b *testing.B) {
+	prototype := []string{"b", "Bz", "zz", "ba", "αβδ αβδ αβδ", "A", "Ba", "ba", "nnnnasdfnnn", "AAgæåz", "αβδC"}
+	b.Run("LessStrings", func(b *testing.B) {
+		ss := make([][]string, b.N)
+		for i := 0; i < b.N; i++ {
+			ss[i] = make([]string, len(prototype))
+			copy(ss[i], prototype)
+		}
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			sss := ss[i]
+			sort.Slice(sss, func(i, j int) bool {
+				return LessStrings(sss[i], sss[j])
+			})
+		}
+	})
+
+}