Fix SetNormalizeFunc (#137)

Related to https://github.com/spf13/cobra/issues/521

1 files changed, 20 insertions, 12 deletions

diff --git a/flag.go b/flag.go
index 85c34a7..b0eb4ff 100644
--- a/flag.go
+++ b/flag.go
@@ -202,12 +202,18 @@ func sortFlags(flags map[NormalizedName]*Flag) []*Flag {
 func (f *FlagSet) SetNormalizeFunc(n func(f *FlagSet, name string) NormalizedName) {
 	f.normalizeNameFunc = n
 	f.sortedFormal = f.sortedFormal[:0]
-	for k, v := range f.orderedFormal {
-		delete(f.formal, NormalizedName(v.Name))
-		nname := f.normalizeFlagName(v.Name)
-		v.Name = string(nname)
-		f.formal[nname] = v
-		f.orderedFormal[k] = v
+	for fname, flag := range f.formal {
+		nname := f.normalizeFlagName(flag.Name)
+		if fname == nname {
+			continue
+		}
+		flag.Name = string(nname)
+		delete(f.formal, fname)
+		f.formal[nname] = flag
+		if _, set := f.actual[fname]; set {
+			delete(f.actual, fname)
+			f.actual[nname] = flag
+		}
 	}
 }
 
@@ -440,13 +446,15 @@ func (f *FlagSet) Set(name, value string) error {
 		return fmt.Errorf("invalid argument %q for %q flag: %v", value, flagName, err)
 	}
 
-	if f.actual == nil {
-		f.actual = make(map[NormalizedName]*Flag)
-	}
-	f.actual[normalName] = flag
-	f.orderedActual = append(f.orderedActual, flag)
+	if !flag.Changed {
+		if f.actual == nil {
+			f.actual = make(map[NormalizedName]*Flag)
+		}
+		f.actual[normalName] = flag
+		f.orderedActual = append(f.orderedActual, flag)
 
-	flag.Changed = true
+		flag.Changed = true
+	}
 
 	if flag.Deprecated != "" {
 		fmt.Fprintf(f.out(), "Flag --%s has been deprecated, %s\n", flag.Name, flag.Deprecated)