1 files changed, 9 insertions, 6 deletions

diff --git a/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java b/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java
index cf099aba..a4437ba6 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java
@@ -44,7 +44,7 @@ public class ProblemScopeProvider extends AbstractProblemScopeProvider {
                         return getVariableScope(context, scope);
                 }
                 if (reference == ProblemPackage.Literals.REFERENCE_DECLARATION__OPPOSITE) {
-                        return getOppositeScope(context, scope);
+                        return getOppositeScope(context);
                 }
                 return scope;
         }
@@ -96,16 +96,19 @@ public class ProblemScopeProvider extends AbstractProblemScopeProvider {
                 }
         }
 
-        protected IScope getOppositeScope(EObject context, IScope delegateScope) {
+        protected IScope getOppositeScope(EObject context) {
                 var referenceDeclaration = EcoreUtil2.getContainerOfType(context, ReferenceDeclaration.class);
                 if (referenceDeclaration == null) {
-                        return delegateScope;
+                        return IScope.NULLSCOPE;
                 }
                 var relation = referenceDeclaration.getReferenceType();
                 if (!(relation instanceof ClassDeclaration classDeclaration)) {
-                        return delegateScope;
+                        return IScope.NULLSCOPE;
                 }
-                var referenceDeclarations = desugarer.getAllReferenceDeclarations(classDeclaration);
-                return Scopes.scopeFor(referenceDeclarations, delegateScope);
+                var referenceDeclarations = classDeclaration.getFeatureDeclarations()
+                                .stream()
+                                .filter(ReferenceDeclaration.class::isInstance)
+                                .toList();
+                return Scopes.scopeFor(referenceDeclarations);
         }
 }