added test for successfully used -v flag on command with subcommands

command_test.go

@@ -389,7 +389,7 @@ func TestCommand_NoVersionFlagOnCommands(t *testing.T) {
 				HideHelp:    true,
 				Action: func(c *Context) error {
 					if len(c.App.VisibleFlags()) != 0 {
-						t.Fatalf("unexpected flag on command")
+						t.Fatal("unexpected flag on command")
 					}
 					return nil
 				},
@@ -400,3 +400,25 @@ func TestCommand_NoVersionFlagOnCommands(t *testing.T) {
 	err := app.Run([]string{"foo", "bar"})
 	expect(t, err, nil)
 }
+
+func TestCommand_CanAddVFlagOnCommands(t *testing.T) {
+	app := &App{
+		Version: "some version",
+		Writer:  ioutil.Discard,
+		Commands: []*Command{
+			{
+				Name:        "bar",
+				Usage:       "this is for testing",
+				Subcommands: []*Command{{}}, // some subcommand
+				Flags: []Flag{
+					&BoolFlag{
+						Name: "v",
+					},
+				},
+			},
+		},
+	}
+
+	err := app.Run([]string{"foo", "bar"})
+	expect(t, err, nil)
+}