fix new split function for go 1.12

Signed-off-by: Ivan Porto Carrero <[email protected]>

name_lexem.go

@@ -14,6 +14,8 @@
 
 package swag
 
+import "unicode"
+
 type (
 	nameLexem interface {
 		GetUnsafeGoName() string
@@ -49,8 +51,20 @@ func (l *initialismNameLexem) GetUnsafeGoName() string {
 }
 
 func (l *casualNameLexem) GetUnsafeGoName() string {
+	var first rune
+	var rest string
+	for i, orig := range l.original {
+		if i == 0 {
+			first = orig
+			continue
+		}
+		if i > 0 {
+			rest = l.original[i:]
+			break
+		}
+	}
 	if len(l.original) > 1 {
-		return upper(l.original[:1]) + lower(l.original[1:])
+		return string(unicode.ToUpper(first)) + lower(rest)
 	}
 
 	return l.original

split.go

@@ -221,8 +221,8 @@ func (s *splitter) breakCasualString(str []rune) []nameLexem {
 		addCasualNameLexem(original)
 	}
 
-	for _, rune := range string(str) {
-		if replace, found := nameReplaceTable[rune]; found {
+	for _, rn := range string(str) {
+		if replace, found := nameReplaceTable[rn]; found {
 			if currentSegment != "" {
 				addNameLexem(currentSegment)
 				currentSegment = ""
@@ -235,7 +235,7 @@ func (s *splitter) breakCasualString(str []rune) []nameLexem {
 			continue
 		}
 
-		if !unicode.In(rune, unicode.L, unicode.M, unicode.N, unicode.Pc) {
+		if !unicode.In(rn, unicode.L, unicode.M, unicode.N, unicode.Pc) {
 			if currentSegment != "" {
 				addNameLexem(currentSegment)
 				currentSegment = ""
@@ -244,14 +244,14 @@ func (s *splitter) breakCasualString(str []rune) []nameLexem {
 			continue
 		}
 
-		if unicode.IsUpper(rune) {
+		if unicode.IsUpper(rn) {
 			if currentSegment != "" {
 				addNameLexem(currentSegment)
 			}
 			currentSegment = ""
 		}
 
-		currentSegment += string(rune)
+		currentSegment += string(rn)
 	}
 
 	if currentSegment != "" {