IsSet breaks with Persistent option about cli HOT 3 CLOSED

func TestPersistentFlagIsSet(t *testing.T) {

	result := ""
	resultIsSet := false

	app := &Command{
		Name: "root",
		Flags: []Flag{
			&StringFlag{
				Name:       "result",
				Persistent: true,
			},
		},
		Commands: []*Command{
			{
				Name: "sub",
				Action: func(_ context.Context, cmd *Command) error {
					result = cmd.String("result")
					resultIsSet = cmd.IsSet("result")
					return nil
				},
			},
		},
	}

	r := require.New(t)

	err := app.Run(context.Background(), []string{"root", "--result", "before", "sub"})
	r.NoError(err)
	r.Equal("before", result)
	r.True(resultIsSet)

	err = app.Run(context.Background(), []string{"root", "sub", "--result", "after"})
	r.NoError(err)
	r.Equal("after", result)
	r.True(resultIsSet)

}