Add flagsNyName back

Author: dearchap

flag.go

@@ -73,6 +73,26 @@ var FlagEnvHinter FlagEnvHintFunc = withEnvHint
 // details. This is used by the default FlagStringer.
 var FlagFileHinter FlagFileHintFunc = withFileHint
 
+// FlagsByName is a slice of Flag.
+type FlagsByName []Flag
+
+func (f FlagsByName) Len() int {
+	return len(f)
+}
+
+func (f FlagsByName) Less(i, j int) bool {
+	if len(f[j].Names()) == 0 {
+		return false
+	} else if len(f[i].Names()) == 0 {
+		return true
+	}
+	return lexicographicLess(f[i].Names()[0], f[j].Names()[0])
+}
+
+func (f FlagsByName) Swap(i, j int) {
+	f[i], f[j] = f[j], f[i]
+}
+
 // ActionableFlag is an interface that wraps Flag interface and RunAction operation.
 type ActionableFlag interface {
 	RunAction(context.Context, *Command) error

flag_test.go

@@ -9,6 +9,7 @@ import (
 	"os"
 	"reflect"
 	"regexp"
+	"sort"
 	"strings"
 	"testing"
 	"time"
@@ -3049,3 +3050,31 @@ func TestFileHint(t *testing.T) {
 	assert.Equal(t, "foo", withFileHint("", "foo"))
 	assert.Equal(t, "bar [/tmp/foo.txt]", withFileHint("/tmp/foo.txt", "bar"))
 }
+
+func TestFlagsByName(t *testing.T) {
+	flags := []Flag{
+		&StringFlag{
+			Name: "b2",
+		},
+		&IntFlag{
+			Name: "a0",
+		},
+		&FloatFlag{
+			Name: "b1",
+		},
+	}
+
+	flagsByName := FlagsByName(flags)
+	sort.Sort(flagsByName)
+
+	assert.Equal(t, len(flags), flagsByName.Len())
+
+	var prev Flag
+	for _, f := range flags {
+		if prev == nil {
+			prev = f
+		} else {
+			assert.LessOrEqual(t, prev.Names()[0], f.Names()[0])
+		}
+	}
+}

godoc-current.txt

@@ -761,6 +761,15 @@ var FlagStringer FlagStringFunc = stringifyFlag
     FlagStringer converts a flag definition to a string. This is used by help to
     display a flag.
 
+type FlagsByName []Flag
+    FlagsByName is a slice of Flag.
+
+func (f FlagsByName) Len() int
+
+func (f FlagsByName) Less(i, j int) bool
+
+func (f FlagsByName) Swap(i, j int)
+
 type FloatArg = ArgumentBase[float64, NoConfig, floatValue]
 
 type FloatFlag = FlagBase[float64, NoConfig, floatValue]

testdata/godoc-v3.x.txt

@@ -761,6 +761,15 @@ var FlagStringer FlagStringFunc = stringifyFlag
     FlagStringer converts a flag definition to a string. This is used by help to
     display a flag.
 
+type FlagsByName []Flag
+    FlagsByName is a slice of Flag.
+
+func (f FlagsByName) Len() int
+
+func (f FlagsByName) Less(i, j int) bool
+
+func (f FlagsByName) Swap(i, j int)
+
 type FloatArg = ArgumentBase[float64, NoConfig, floatValue]
 
 type FloatFlag = FlagBase[float64, NoConfig, floatValue]