Calling the same unit twice with different parameters leads to unwanted behavior.

[neumde]

In the following henshin code I create two nodes in the graph with an edge to the given EventType.

// Is called by RunTransformation.java
unit doFSM(IN eventTypeName1:EString, IN eventTypeName2:EString, VAR firstState: State) {
	createEvent(eventTypeName1)
	createEvent(eventTypeName2)
}

rule createEvent(IN eventTypeName:EString){
	graph {
		preserve node runtimeState:CurrentState
		preserve node evenType: EventType {
			name = eventTypeName
		}
		
		create node event:Event {}
		edges[(create event->evenType:type),		
			(create runtimeState->event:eventQueue)]
	}
}

Since the following code sets the two parameters I would expect to create two events, one of type "E_NEXT" and one of type "E_LONG". However, due to a wrong parameter mapping, both events are of type "E_LONG" (the last parameter that is set).
This is the java file which sets the parameters and calls the unit:

	public static void main(String[] args) {
		HenshinResourceSet resourceSet=new HenshinResourceSet("./src/runTransformation");
		resourceSet.getPackageRegistry().put(HfsmPackage.eNS_URI, HfsmPackage.eINSTANCE);
		resourceSet.getResourceFactoryRegistry().getExtensionToFactoryMap().put("xmi", new XMIResourceFactoryImpl());
		

		Resource resource=resourceSet.getResource(filePath);		
		EGraph eGraph=new EGraphImpl(resource);		
		Module module=resourceSet.getModule(transformationPath, true);		
		Engine engine=new EngineImpl();
		
		Unit initHFSM=module.getUnit("doFSM");		
		UnitApplication application = new UnitApplicationImpl(engine, eGraph, initHFSM, null);
				
		
		application.setParameterValue("eventTypeName1", "E_NEXT");
		application.setParameterValue("eventTypeName2", "E_LONG");
		application.execute(null);

Expected parameter mappings:

eventTypeName1 -> "E_NEXT"
eventTypeName2 -> "E_LONG"

The actual parameter mappings apparently:

eventTypeName1 -> "E_LONG"
eventTypeName2 -> "E_LONG"

Troubleshooting approaches:

• I tried different parameter kinds but this didn't change the outcome.

This is not a problem of the textual henshin syntax, instead the problem seems to be the handling of ParameterMappings in the method createApplicationFor(Unit subUnit).
It seems like the last (fitting) ParameterMapping is selected, instead of the right one for the specific unit call.

[mtttichy]

I can confirm the problem in the code. I see two possible solutions:

1. (the proper solution) Introduce an UnitCall-Metaclass. This UnitCall-Metaclass can store the argument for the parameter (the parameter mapping).
2. (workaround) use the index of subUnit in the surroundung unit and use that index to use the correct parameterMapping