[Go] Prefix enum number with _ (#703)

* prefix enum number with _ in go

* reformat code, use else if

Author: wing328

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractGoCodegen.java

@@ -145,7 +145,7 @@ public String escapeReservedWord(String name) {
 
     @Override
     public String toVarName(String name) {
-        
+
         // replace - with _ e.g. created-at => created_at
         name = sanitizeName(name);
 
@@ -267,10 +267,10 @@ public String getTypeDeclaration(Schema p) {
         // the type.
         String openAPIType = getSchemaType(p);
         String ref = p.get$ref();
-        if(ref != null && !ref.isEmpty()) {
+        if (ref != null && !ref.isEmpty()) {
             String tryRefV2 = "#/definitions/" + openAPIType;
             String tryRefV3 = "#/components/schemas/" + openAPIType;
-            if(ref.equals(tryRefV2) || ref.equals(tryRefV3)) {
+            if (ref.equals(tryRefV2) || ref.equals(tryRefV3)) {
                 return toModelName(openAPIType);
             }
         }
@@ -296,7 +296,7 @@ public String getSchemaType(Schema p) {
         String ref = p.get$ref();
         String type = null;
 
-        if(ref != null && !ref.isEmpty()) {
+        if (ref != null && !ref.isEmpty()) {
             type = openAPIType;
         } else if (typeMapping.containsKey(openAPIType)) {
             type = typeMapping.get(openAPIType);
@@ -570,8 +570,10 @@ public String toEnumVarName(String name, String datatype) {
         enumName = enumName.replaceFirst("^_", "");
         enumName = enumName.replaceFirst("_$", "");
 
-        if (isReservedWord(enumName) || enumName.matches("\\d.*")) { // reserved word or starts with number
+        if (isReservedWord(enumName)) { // reserved word
             return escapeReservedWord(enumName);
+        } else if (enumName.matches("\\d.*")) { // starts with a number
+            return "_" + enumName;
         } else {
             return enumName;
         }

samples/client/petstore/go/go-petstore-withXml/.openapi-generator/VERSION

@@ -1 +1 @@
-3.1.1-SNAPSHOT
+3.2.0-SNAPSHOT