upb: fix Dart empty imports

PiperOrigin-RevId: 627794151

upb/reflection/def.hpp

@@ -105,6 +105,7 @@ class FieldDefPtr {
   OneofDefPtr real_containing_oneof() const;
 
   // Convenient field type tests.
+  bool IsEnum() const { return upb_FieldDef_IsEnum(ptr_); }
   bool IsSubMessage() const { return upb_FieldDef_IsSubMessage(ptr_); }
   bool IsString() const { return upb_FieldDef_IsString(ptr_); }
   bool IsSequence() const { return upb_FieldDef_IsRepeated(ptr_); }

upb/reflection/field_def.c

@@ -208,11 +208,11 @@ upb_MessageValue upb_FieldDef_Default(const upb_FieldDef* f) {
 }
 
 const upb_MessageDef* upb_FieldDef_MessageSubDef(const upb_FieldDef* f) {
-  return upb_FieldDef_CType(f) == kUpb_CType_Message ? f->sub.msgdef : NULL;
+  return upb_FieldDef_IsSubMessage(f) ? f->sub.msgdef : NULL;
 }
 
 const upb_EnumDef* upb_FieldDef_EnumSubDef(const upb_FieldDef* f) {
-  return upb_FieldDef_CType(f) == kUpb_CType_Enum ? f->sub.enumdef : NULL;
+  return upb_FieldDef_IsEnum(f) ? f->sub.enumdef : NULL;
 }
 
 const upb_MiniTableField* upb_FieldDef_MiniTable(const upb_FieldDef* f) {
@@ -310,8 +310,11 @@ bool upb_FieldDef_HasDefault(const upb_FieldDef* f) { return f->has_default; }
 bool upb_FieldDef_HasPresence(const upb_FieldDef* f) { return f->has_presence; }
 
 bool upb_FieldDef_HasSubDef(const upb_FieldDef* f) {
-  return upb_FieldDef_IsSubMessage(f) ||
-         upb_FieldDef_CType(f) == kUpb_CType_Enum;
+  return upb_FieldDef_IsSubMessage(f) || upb_FieldDef_IsEnum(f);
+}
+
+bool upb_FieldDef_IsEnum(const upb_FieldDef* f) {
+  return upb_FieldDef_CType(f) == kUpb_CType_Enum;
 }
 
 bool upb_FieldDef_IsMap(const upb_FieldDef* f) {

upb/reflection/field_def.h

@@ -45,6 +45,7 @@ bool upb_FieldDef_HasOptions(const upb_FieldDef* f);
 UPB_API bool upb_FieldDef_HasPresence(const upb_FieldDef* f);
 bool upb_FieldDef_HasSubDef(const upb_FieldDef* f);
 uint32_t upb_FieldDef_Index(const upb_FieldDef* f);
+UPB_API bool upb_FieldDef_IsEnum(const upb_FieldDef* f);
 bool upb_FieldDef_IsExtension(const upb_FieldDef* f);
 UPB_API bool upb_FieldDef_IsMap(const upb_FieldDef* f);
 bool upb_FieldDef_IsOptional(const upb_FieldDef* f);