2 files changed, 37 insertions, 1 deletions

diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/Dnf2PQuery.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/Dnf2PQuery.java
index 38fd017e..d51bc9fc 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/Dnf2PQuery.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/pquery/Dnf2PQuery.java
@@ -88,7 +88,7 @@ public class Dnf2PQuery {
                 List<PParameter> parameterList = new ArrayList<>();
                 for (var parameter : dnfQuery.getSymbolicParameters()) {
                         var direction = switch (parameter.getDirection()) {
-                                case OUT -> parameter.isUnifiable() ? PParameterDirection.INOUT : PParameterDirection.OUT;
+                                case OUT -> PParameterDirection.INOUT;
                                 case IN -> throw new IllegalArgumentException("Query %s with input parameter %s is not supported"
                                                 .formatted(dnfQuery, parameter.getVariable()));
                         };
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/FunctionalQueryTest.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/FunctionalQueryTest.java
index c4f877c5..7f5c24fe 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/FunctionalQueryTest.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/FunctionalQueryTest.java
@@ -424,6 +424,42 @@ class FunctionalQueryTest {
         }
 
         @QueryEngineTest
+        void multipleAssignmentTest(QueryEvaluationHint hint) {
+                var query = Query.of("MultipleAssignment", Integer.class, (builder, p1, p2, output) -> builder
+                                .clause(Integer.class, Integer.class, (x1, x2) -> List.of(
+                                                ageView.call(p1, x1),
+                                                ageView.call(p2, x2),
+                                                output.assign(mul(x1, constant(2))),
+                                                output.assign(mul(x2, constant(3)))
+                                )));
+
+                var store = ModelStore.builder()
+                                .symbols(age)
+                                .with(ViatraModelQueryAdapter.builder()
+                                                .defaultHint(hint)
+                                                .queries(query))
+                                .build();
+
+                var model = store.createEmptyModel();
+                var ageInterpretation = model.getInterpretation(age);
+                var queryEngine = model.getAdapter(ModelQueryAdapter.class);
+                var queryResultSet = queryEngine.getResultSet(query);
+
+                ageInterpretation.put(Tuple.of(0), 3);
+                ageInterpretation.put(Tuple.of(1), 2);
+                ageInterpretation.put(Tuple.of(2), 15);
+                ageInterpretation.put(Tuple.of(3), 10);
+
+                queryEngine.flushChanges();
+                assertNullableResults(Map.of(
+                                Tuple.of(0, 1), Optional.of(6),
+                                Tuple.of(1, 0), Optional.empty(),
+                                Tuple.of(2, 3), Optional.of(30),
+                                Tuple.of(3, 2), Optional.empty()
+                ), queryResultSet);
+        }
+
+        @QueryEngineTest
         void notFunctionalTest(QueryEvaluationHint hint) {
                 var query = Query.of("NotFunctional", Integer.class, (builder, p1, output) -> builder.clause((p2) -> List.of(
                                 personView.call(p1),