Old Prefs from OMNeT 5.6 QtEnv cause silent error in OMNeT++ 6 QTEnv

[edlongman]

Platform

• OMNeT++ version: 5.6 & 6
• OS: Windows 10

Describe the bug
Shared preferences between OMNeT versions can cause simulations to fail cryptically.

I receive the error:

<!> Error: Parse error in match expression: syntax error

Even in debug mode it does not trigger a debug breakpoint.

To Reproduce

1. Run an OMNeT 5.6 QTEnv simulation
2. Open Preference > Filtering > Animation
3. Enter Filter: module(*.packetSource)
4. Run OMNeT 6 Simulation

** Approximate error source **

omnetpp/src/qtenv/qtenv.cc

Lines 245 to 367 in 5997cd4

	void Qtenv::restoreOptsFromPrefs()
	{
	auto pref = getPref("updatefreq_express_ms");
	if (pref.isValid())
	opt->updateFreqExpress = pref.toLongLong();
	pref = getPref("event_banners");
	if (pref.isValid())
	opt->printEventBanners = pref.toBool();
	pref = getPref("init_banners");
	if (pref.isValid())
	opt->printInitBanners = pref.toBool();
	pref = getPref("short_banners");
	if (pref.isValid())
	opt->shortBanners = pref.toBool();
	pref = getPref("allow_backward_arrows");
	if (pref.isValid())
	opt->allowBackwardArrowsForHops = pref.toBool();
	pref = getPref("messagelog_digitgrouping");
	if (pref.isValid())
	opt->messageLogDigitGrouping = pref.toBool();
	pref = getPref("no_logging_refreshdisplay");
	if (pref.isValid())
	opt->noLoggingRefreshDisplay = pref.toBool();
	pref = getPref("animation_enabled");
	if (pref.isValid())
	opt->animationEnabled = pref.toBool();
	pref = getPref("nexteventmarkers");
	if (pref.isValid())
	opt->showNextEventMarkers = pref.toBool();
	pref = getPref("senddirect_arrows");
	if (pref.isValid())
	opt->showSendDirectArrows = pref.toBool();
	pref = getPref("animation_methodcalls");
	if (pref.isValid())
	opt->animateMethodCalls = pref.toBool();
	pref = getPref("methodcalls_duration");
	if (pref.isValid())
	opt->methodCallAnimDuration = pref.toInt();
	pref = getPref("animation_msgnames");
	if (pref.isValid())
	opt->animationMsgNames = pref.toBool();
	pref = getPref("animation_msgclassnames");
	if (pref.isValid())
	opt->animationMsgClassNames = pref.toBool();
	pref = getPref("animation_msgcolors");
	if (pref.isValid())
	opt->animationMsgColors = pref.toBool();
	pref = getPref("silent_event_filters");
	if (pref.isValid())
	setSilentEventFilters(pref.toString().toStdString().c_str());
	pref = getPref("penguin_mode");
	if (pref.isValid())
	opt->penguinMode = pref.toBool();
	pref = getPref("showlayouting");
	if (pref.isValid())
	opt->showLayouting = pref.toBool();
	pref = getPref("layouterchoice");
	if (pref.isValid()) {
	QString layouterChoiceString = pref.toString();
	if (layouterChoiceString == "fast") {
	opt->layouterChoice = LAYOUTER_FAST;
	}
	else if (layouterChoiceString == "advanced") {
	opt->layouterChoice = LAYOUTER_ADVANCED;
	}
	else if (layouterChoiceString == "auto") {
	opt->layouterChoice = LAYOUTER_AUTO;
	}
	}
	pref = getPref("arrangevectorconnections");
	if (pref.isValid())
	opt->arrangeVectorConnections = pref.toBool();
	pref = getPref("bubbles");
	if (pref.isValid())
	opt->showBubbles = pref.toBool();
	pref = getPref("expressmode_autoupdate");
	if (pref.isValid())
	opt->autoupdateInExpress = pref.toBool();
	pref = getPref("stripnamespace");
	if (pref.isValid()) {
	QString stripNamespaceString = pref.toString();
	if (stripNamespaceString == "none") {
	opt->stripNamespace = STRIPNAMESPACE_NONE;
	}
	else if (stripNamespaceString == "omnetpp") {
	opt->stripNamespace = STRIPNAMESPACE_OMNETPP;
	}
	else if (stripNamespaceString == "all") {
	opt->stripNamespace = STRIPNAMESPACE_ALL;
	}
	}
	// overriding opts from prefs, but using the current ones (factory defaults) as fallback if no pref was stored yet
	opt->logFormat = getPref("logformat", opt->logFormat.c_str()).toString().toStdString();
	try { // level is stored as string, so we have to convert there and back. also have to store in opt, also forward to cLog via setter
	opt->logLevel = cLog::resolveLogLevel(getPref("loglevel", cLog::getLogLevelName(opt->logLevel)).toByteArray());
	} catch (cRuntimeError &) { } // resolveLogLevel might throw, but we can ignore it, and not change the factory default
	pref = getPref("logbuffer_maxnumevents");
	if (pref.isValid())
	logBuffer.setMaxNumEntries(pref.toInt());

[rhornig]

Indeed, we should not throw exception on recoverable errors.