Restrict Xtext scoping to folder

Question

When having two Xtext models in the same project but in different folders using the same names (ID) for different objects, the scoping does not work how I want it to. How can I restrict the scoping to inside one folder and not the whole project? Example:

grammar:

Model:
    persons+=Person*
    greetings+=Greeting*;
Greeting:
    'Hello' name=[Person] '!';
Person:
    'person' name=ID;

folder structure:

project
 |-folder1
   |-person1.mydsl
 |-folder2
   |-greeting.mydsl
   |-person2.mydsl

person1.mydsl contains a Person ("Jane"), person2.mydsl also contains a Person ("Jane") and greeting.mydsl contains a Greeting ("Hello Jane!") referencing the person in person1.mydsl instead of the person in person2.mydsl.

The documentation tells me to use the StateBasedContainerManager but I don't understand where and how.

in your case you should implement/customize IGlobalScopeProvider and filter the default global scope (DefaultGlobalScopeProvider) to filter for same prefix in uri. — Christian Dietrich
At which point am I able to add my filter? I only see the possibility to edit the scoping in MyDslScopeProvider (extends AbstractMyDslScopeProvider). I probably have to change which IGlobalScopeProvider is getting injected into XtextScopeProvider? — Marie-Saphira
as i said: org.eclipse.xtext.scoping.IGlobalScopeProvider.getScope(Resource, EReference, Predicate<IEObjectDescription>) — Christian Dietrich
yes, the question was about how to tell my xtext plugin to use my changed IGlobalScopeProvider, but I found it and will answer my question, thanks for your help — Marie-Saphira

Marie-Saphira Marie-Saphira · Accepted Answer · 2021-01-04T19:07:52

Thanks to @Christian and this I found a solution. So first adding a filter to the DefaultGlobalScopeProvider

public class MyGlobalScopeProvider extends DefaultGlobalScopeProvider {
    @Override
    public IScope getScope(Resource resource, EReference reference, Predicate<IEObjectDescription> filter) {
        filter = new Predicate<IEObjectDescription>() {
            @Override
            public boolean apply(IEObjectDescription input) {
                // implement here
            }
        };
        return super.getScope(resource, reference, filter);
    }
}

and then telling my runtime module to use my provider instead

public class MyDslRuntimeModule extends AbstractMyDslRuntimeModule {
    @Override
    public Class<? extends IGlobalScopeProvider> bindIGlobalScopeProvider() {
        return MyGlobalScopeProvider.class;
    }
}

Restrict Xtext scoping to folder

1 Answers