[2441] Extract semantic creation from createAllocateEdge

CHANGELOG.adoc

@@ -75,6 +75,7 @@ This removes Rollup warnings about missing global names for externalized peer de
 - [cleanup] Use only one border node description provider for all item border nodes.
 - https://github.com/eclipse-syson/syson/issues/2452[#2352] [diagram] Decouple SysON tools from Sirius Web's DefaultToolsFactory: SysON now defines its own `DiagramDefaultToolsFactory` providing show/hide tools.
 - https://github.com/eclipse-syson/syson/issues/2453[#2453] [diagrams] Add the Show/Hide section and associated tools to the group palette.
+- https://github.com/eclipse-syson/syson/issues/2441[#2441] [services] Refactor `DiagramMutationElementService#createAllocateEdge` to extract semantic creation from diagram service.
 
 === New features
 

backend/services/syson-diagram-services/src/main/java/org/eclipse/syson/diagram/services/DiagramMutationElementService.java

@@ -751,17 +751,12 @@ public IncludeUseCaseUsage createIncludeUseCaseUsage(UseCaseUsage source, UseCas
      *            the current editing context
      * @param diagramService
      *            the current diagram service
-     * @return the given source element
+     * @return the created {@link AllocationUsage}
      */
-    public Element createAllocateEdge(Element source, Element target, Node sourceNode, IEditingContext editingContext, IDiagramService diagramService) {
-        var owner = source.getOwner();
-        var ownerMembership = SysmlFactory.eINSTANCE.createOwningMembership();
-        owner.getOwnedRelationship().add(ownerMembership);
-        var allocation = SysmlFactory.eINSTANCE.createAllocationUsage();
-        ownerMembership.getOwnedRelatedElement().add(allocation);
-        this.addEndToAllocateEdge(allocation, source);
-        this.addEndToAllocateEdge(allocation, target);
-        return source;
+    public AllocationUsage createAllocateEdge(Element source, Element target, Node sourceNode, IEditingContext editingContext, IDiagramService diagramService) {
+        var allocateEdge = this.metamodelMutationElementService.createAllocateEdge(source, target);
+        this.metamodelMutationElementService.initialize(allocateEdge);
+        return allocateEdge;
     }
 
     /**
@@ -838,18 +833,6 @@ public Element reconnectSourceAllocateEdge(AllocationUsage allocationUsage, Elem
         return allocationUsage;
     }
 
-    private void addEndToAllocateEdge(AllocationUsage edge, Element end) {
-        if (end instanceof Usage usage) {
-            var featureMembership = SysmlFactory.eINSTANCE.createEndFeatureMembership();
-            edge.getOwnedRelationship().add(featureMembership);
-            var feature = SysmlFactory.eINSTANCE.createFeature();
-            featureMembership.getOwnedRelatedElement().add(feature);
-            var reference = SysmlFactory.eINSTANCE.createReferenceSubsetting();
-            feature.getOwnedRelationship().add(reference);
-            reference.setReferencedFeature(usage);
-        }
-    }
-
     /**
      * Reconnects the target of an allocate edge.
      *

backend/services/syson-sysml-metamodel-services/src/main/java/org/eclipse/syson/sysml/metamodel/services/MetamodelMutationElementService.java

@@ -18,6 +18,7 @@
 import org.eclipse.emf.ecore.EObject;
 import org.eclipse.emf.ecore.EReference;
 import org.eclipse.emf.ecore.EStructuralFeature;
+import org.eclipse.syson.sysml.AllocationUsage;
 import org.eclipse.syson.sysml.BindingConnectorAsUsage;
 import org.eclipse.syson.sysml.ConnectionUsage;
 import org.eclipse.syson.sysml.Connector;
@@ -48,6 +49,7 @@
 import org.eclipse.syson.sysml.SysmlFactory;
 import org.eclipse.syson.sysml.SysmlPackage;
 import org.eclipse.syson.sysml.Type;
+import org.eclipse.syson.sysml.Usage;
 
 /**
  * Element-related services doing mutations. This class should not depend on sirius-web services or other spring
@@ -386,6 +388,36 @@ public Documentation createObjectiveDocumentation(Element element, String refere
         return null;
     }
 
+    /**
+     * Creates an allocate edge between the given source and target.
+     *
+     * @param source the source of the allocate edge
+     * @param target the target of the allocate edge
+     * @return the created {@link AllocationUsage}
+     */
+    public AllocationUsage createAllocateEdge(Element source, Element target) {
+        var owner = source.getOwner();
+        var ownerMembership = SysmlFactory.eINSTANCE.createOwningMembership();
+        owner.getOwnedRelationship().add(ownerMembership);
+        var allocation = SysmlFactory.eINSTANCE.createAllocationUsage();
+        ownerMembership.getOwnedRelatedElement().add(allocation);
+        this.addEndToAllocateEdge(allocation, source);
+        this.addEndToAllocateEdge(allocation, target);
+        return allocation;
+    }
+
+    private void addEndToAllocateEdge(AllocationUsage edge, Element end) {
+        if (end instanceof Usage usage) {
+            var featureMembership = SysmlFactory.eINSTANCE.createEndFeatureMembership();
+            edge.getOwnedRelationship().add(featureMembership);
+            var feature = SysmlFactory.eINSTANCE.createFeature();
+            featureMembership.getOwnedRelatedElement().add(feature);
+            var reference = SysmlFactory.eINSTANCE.createReferenceSubsetting();
+            feature.getOwnedRelationship().add(reference);
+            reference.setReferencedFeature(usage);
+        }
+    }
+
     private Feature addConnectorEnd(Connector connector, Feature end, Element endContainer, Element connectorContainer, FeatureDirectionKind defaultDirection) {
         List<Feature> sourceFeaturePath = List.of();
         // This code will not work to connect inherited non redefined feature.

backend/services/syson-sysml-metamodel-services/src/test/java/org/eclipse/syson/sysml/metamodel/services/MetamodelMutationElementServiceTest.java

@@ -18,6 +18,7 @@
 import java.util.List;
 import java.util.Objects;
 
+import org.eclipse.syson.sysml.AllocationUsage;
 import org.eclipse.syson.sysml.ConnectionUsage;
 import org.eclipse.syson.sysml.Element;
 import org.eclipse.syson.sysml.FeatureDirectionKind;
@@ -26,6 +27,7 @@
 import org.eclipse.syson.sysml.MetadataUsage;
 import org.eclipse.syson.sysml.OwningMembership;
 import org.eclipse.syson.sysml.Package;
+import org.eclipse.syson.sysml.PartUsage;
 import org.eclipse.syson.sysml.ReferenceUsage;
 import org.eclipse.syson.sysml.RequirementUsage;
 import org.eclipse.syson.sysml.SysmlFactory;
@@ -188,6 +190,22 @@ public void createFlowUsageBetweenFeatureWithoutDirection() {
         assertThat(targetFlow).isEqualTo(target);
     }
 
+    @Test
+    @DisplayName("GIVEN two PartUsage, WHEN creating an allocate edge, then an AllocationUsage is created with the correct ends")
+    public void createAllocateEdge() {
+        Package parentPackage = SysmlFactory.eINSTANCE.createPackage();
+        PartUsage partUsage1 = SysmlFactory.eINSTANCE.createPartUsage();
+        this.mutationService.addChildInParent(parentPackage, partUsage1);
+        PartUsage partUsage2 = SysmlFactory.eINSTANCE.createPartUsage();
+        this.mutationService.addChildInParent(parentPackage, partUsage2);
+        AllocationUsage allocationUsage = this.mutationService.createAllocateEdge(partUsage1, partUsage2);
+        assertThat(allocationUsage).isNotNull();
+        assertThat(allocationUsage.getFeature())
+                .hasSize(2)
+                .anySatisfy(feature -> assertThat(feature.getOwnedReferenceSubsetting().getReferencedFeature()).isEqualTo(partUsage1))
+                .anySatisfy(feature -> assertThat(feature.getOwnedReferenceSubsetting().getReferencedFeature()).isEqualTo(partUsage2));
+    }
+
     private RequirementUsage createRequirement(String name) {
         RequirementUsage requirement = SysmlFactory.eINSTANCE.createRequirementUsage();
         requirement.setDeclaredName(name);