fix a bug that caused shorthand name for slice doesn't get generated

Author: hujun-open

example/main.go

@@ -14,7 +14,7 @@ import (
 type ZipCLI struct {
 	ConfigFile     string       `short:"c" usage:"working profile"`
 	SvrAddr        net.IP       `usage:"server address to download the archive" complete:"SvrComplete"` //using completer method SvrComplete for shell completion
-	BackupAddrList []netip.Addr `usage:"backup server address list"`
+	BackupAddrList []netip.Addr `short:"b" usage:"backup server address list"`
 	Compress       struct {
 		Loop      uint   `base:"16" short:"l" usage:"number of compress iterations"`
 		Profile   string `usage:"compress profile" choices:"p1,p2,p3"` //using choices for shell compeltion

list.go

@@ -116,11 +116,12 @@ func getListType(ref reflect.Value, tag reflect.StructTag) (*listType, error) {
 	return &newval, nil
 }
 
-func processList(fs *flag.FlagSet, ref reflect.Value, tag reflect.StructTag, name, usage string) error {
+func processList(fs *flag.FlagSet, ref reflect.Value, tag reflect.StructTag, name, short, usage string) error {
 	newlist, err := getListType(ref, tag)
 	if err != nil {
 		return err
 	}
-	fs.Var(newlist, name, usage)
+	fs.VarP(newlist, name, short, usage)
+
 	return nil
 }

myflags.go

@@ -734,7 +734,7 @@ func (filler *Filler) walk(root, inV reflect.Value, nameprefix string, isAct boo
 						}
 					}
 					if process {
-						err = processList(fs, field.Addr(), fieldT.Tag, fname, usage)
+						err = processList(fs, field.Addr(), fieldT.Tag, fname, fshort, usage)
 						if err != nil {
 							return err
 						}