Add lua exception handling test code

Catch some error situations when mod used without thinking about it

src/script/lua_api/l_server.cpp

@@ -24,6 +24,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "server.h"
 #include "environment.h"
 #include "player.h"
+#include "log.h"
 
 // request_shutdown()
 int ModApiServer::l_request_shutdown(lua_State *L)
@@ -449,6 +450,36 @@ int ModApiServer::l_notify_authentication_modified(lua_State *L)
 	return 0;
 }
 
+#ifndef NDEBUG
+// cause_error(type_of_error)
+int ModApiServer::l_cause_error(lua_State *L)
+{
+	NO_MAP_LOCK_REQUIRED;
+	std::string type_of_error = "none";
+	if(lua_isstring(L, 1))
+		type_of_error = lua_tostring(L, 1);
+
+	errorstream << "Error handler test called, errortype=" << type_of_error << std::endl;
+
+	if(type_of_error == "segv") {
+		volatile int* some_pointer = 0;
+		errorstream << "Cause a sigsegv now: " << (*some_pointer) << std::endl;
+
+	} else if (type_of_error == "zerodivision") {
+
+		unsigned int some_number = porting::getTimeS();
+		unsigned int zerovalue = 0;
+		unsigned int result = some_number / zerovalue;
+		errorstream << "Well this shouldn't ever be shown: " << result << std::endl;
+
+	} else if (type_of_error == "exception") {
+		throw BaseException("Errorhandler test fct called");
+	}
+
+	return 0;
+}
+#endif
+
 void ModApiServer::Initialize(lua_State *L, int top)
 {
 	API_FCT(request_shutdown);
@@ -475,4 +506,8 @@ void ModApiServer::Initialize(lua_State *L, int top)
 	API_FCT(kick_player);
 	API_FCT(unban_player_or_ip);
 	API_FCT(notify_authentication_modified);
+
+#ifndef NDEBUG
+	API_FCT(cause_error);
+#endif
 }

src/script/lua_api/l_server.h

@@ -88,6 +88,11 @@ private:
 	// notify_authentication_modified(name)
 	static int l_notify_authentication_modified(lua_State *L);
 
+#ifndef NDEBUG
+	//  cause_error(type_of_error)
+	static int l_cause_error(lua_State *L);
+#endif
+
 public:
 	static void Initialize(lua_State *L, int top);