Add Protobuf.HasField native.

core/UserMessagePBHelpers.h

@@ -118,6 +118,13 @@ public:
 		return msg;
 	}
 
+	inline bool HasField(const char *pszFieldName)
+	{
+		GETCHECK_FIELD();
+		CHECK_FIELD_NOT_REPEATED();
+		return msg->GetReflection()->HasField(*msg, field);
+	}
+
 	inline bool GetInt32(const char *pszFieldName, int32 *out)
 	{
 		GETCHECK_FIELD();

core/smn_protobuf.cpp

@@ -304,6 +304,14 @@ static cell_t smn_PbGetRepeatedFieldCount(IPluginContext *pCtx, const cell_t *pa
 	return cnt;
 }
 
+static cell_t smn_PbHasField(IPluginContext *pCtx, const cell_t *params)
+{
+	GET_MSG_FROM_HANDLE_OR_ERR();
+	GET_FIELD_NAME_OR_ERR();
+
+	return msg->HasField(strField) ? 1 : 0;
+}
+
 static cell_t smn_PbSetInt(IPluginContext *pCtx, const cell_t *params)
 {
 	GET_MSG_FROM_HANDLE_OR_ERR();
@@ -778,6 +786,7 @@ REGISTER_NATIVES(protobufnatives)
 	{"Protobuf.ReadVector",					smn_PbReadVector},
 	{"Protobuf.ReadVector2D",				smn_PbReadVector2D},
 	{"Protobuf.GetRepeatedFieldCount",		smn_PbGetRepeatedFieldCount},
+	{"Protobuf.HasField",					smn_PbHasField},
 	{"Protobuf.SetInt",						smn_PbSetInt},
 	{"Protobuf.SetFloat",					smn_PbSetFloat},
 	{"Protobuf.SetBool",					smn_PbSetBool},