flag: replace sort.Slice with slices.SortFunc

Change-Id: I874f0c0399cb09de4fe4dd2097602c5fa0512b12
GitHub-Last-Rev: 73be01ae2a27adf0b7629a198057674018b5d392
GitHub-Pull-Request: golang/go#67223
Reviewed-on: https://go-review.googlesource.com/c/go/+/583735
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

src/flag/flag.go

@@ -90,7 +90,7 @@ import (
 	"os"
 	"reflect"
 	"runtime"
-	"sort"
+	"slices"
 	"strconv"
 	"strings"
 	"time"
@@ -420,8 +420,8 @@ func sortFlags(flags map[string]*Flag) []*Flag {
 		result[i] = f
 		i++
 	}
-	sort.Slice(result, func(i, j int) bool {
-		return result[i].Name < result[j].Name
+	slices.SortFunc(result, func(a, b *Flag) int {
+		return strings.Compare(a.Name, b.Name)
 	})
 	return result
 }

src/flag/flag_test.go

@@ -14,7 +14,7 @@ import (
 	"os/exec"
 	"regexp"
 	"runtime"
-	"sort"
+	"slices"
 	"strconv"
 	"strings"
 	"testing"
@@ -101,7 +101,7 @@ func TestEverything(t *testing.T) {
 	// Now test they're visited in sort order.
 	var flagNames []string
 	Visit(func(f *Flag) { flagNames = append(flagNames, f.Name) })
-	if !sort.StringsAreSorted(flagNames) {
+	if !slices.IsSorted(flagNames) {
 		t.Errorf("flag names not sorted: %v", flagNames)
 	}
 }