[1998] Add Implicit TypeFeaturing

Bug: #1998
Signed-off-by: Arthur Daussy <arthur.daussy@obeo.fr>

Author: adaussy

CHANGELOG.adoc

@@ -43,6 +43,7 @@ For example `ViewUsage` elements are no longer rendered in _parts_ compartments.
 - https://github.com/eclipse-syson/syson/issues/1949[#1949] [diagrams] Allow redefining a `PartUsage` with the same name as the redefined usage.
 - https://github.com/eclipse-syson/syson/issues/1863[#1863] [diagrams] Dropping an elements on a diagram which is already visible gives feedback again.
 - https://github.com/eclipse-syson/syson/issues/2026[#2026] [explorer] Fix an issue where creating a new model using the _Create a new model_ action in the _Explorer_ view was not adding the ".sysml" extension to the model name.
+- https://github.com/eclipse-syson/syson/issues/1998[#1998] [metamodel] Missing implicit TypeFeaturing.
 
 === Improvements
 

backend/metamodel/syson-sysml-metamodel/src/main/java/org/eclipse/syson/sysml/impl/FeatureImpl.java

@@ -45,10 +45,14 @@
 import org.eclipse.syson.sysml.OwningMembership;
 import org.eclipse.syson.sysml.Redefinition;
 import org.eclipse.syson.sysml.ReferenceSubsetting;
+import org.eclipse.syson.sysml.Specialization;
 import org.eclipse.syson.sysml.Subsetting;
+import org.eclipse.syson.sysml.SysmlFactory;
 import org.eclipse.syson.sysml.SysmlPackage;
 import org.eclipse.syson.sysml.Type;
 import org.eclipse.syson.sysml.TypeFeaturing;
+import org.eclipse.syson.sysml.util.ILibraryNamespaceProvider;
+import org.eclipse.syson.sysml.util.LibraryNamespaceProvider;
 
 /**
  * <!-- begin-user-doc --> An implementation of the model object '<em><b>Feature</b></em>'. <!-- end-user-doc -->
@@ -462,6 +466,13 @@ public EList<Type> getFeaturingType() {
         if (!chainingFeature.isEmpty()) {
             featuringTypes.addAll(chainingFeature.get(0).getFeaturingType());
         }
+
+        // Add implicit featuring type
+        Type implicitType = this.computeImplicitFeaturingType();
+        if (implicitType != null) {
+            featuringTypes.add(implicitType);
+        }
+
         return new EcoreEList.UnmodifiableEList<>(this, SysmlPackage.eINSTANCE.getFeature_FeaturingType(), featuringTypes.size(), featuringTypes.toArray());
     }
 
@@ -1539,4 +1550,59 @@ private Collection<Feature> collectTypingFeatures() {
         }
         return featureCollector;
     }
+
+    /**
+     * @generated NOT
+     */
+    private Type computeImplicitFeaturingType() {
+        Type owningType = this.getOwningType();
+        Type implicitType = null;
+        if (owningType != null) {
+
+            if (!this.isIsVariable()) {
+                // KerML 7.3.2.6 “Feature Membership” – “A feature that is declared within the body of a type … automatically has that type as a featuring type.”
+                // SysML 8.3.3.1.6 FeatureMembership - If the ownedMemberFeature has isVariable = false, then the FeatureMembership implies that the owningType is also a featuringType of the
+                // ownedMemberFeature.
+                implicitType = owningType;
+            } else {
+                // KerML 8.4.4.3
+                // Class (or any Type that directly or indirectly specializes Occurrence) may have ownedFeatures with
+                // isVariable = true. The checkFeatureFeatureMembershipTypeFeaturing constraint requires that such
+                //  variable Features are featured by the snapshots of their owningType.
+                TypeFeaturing typeFeaturing = SysmlFactory.eINSTANCE.createTypeFeaturing();
+                typeFeaturing.setIsImplied(true);
+
+                // Table 9. Core Semantics Implied Relationships Supporting Kernel Semantics - Note 1
+                // For the checkFeatureFeatureMembershipTypeFeaturing constraint, if the Feature has
+                //isVariable = false, then the target Type is the owningType of the Feature. If the Feature has
+                //isVariable = true and the owningType is the base Class Occurrences::Occurrence, then the
+                //target is Occurrences::Occurrence::snapshots (see 9.2.4.2.13 ). Otherwise, the target Type shall
+                //be constructed so as to satisfy the constraint and shall be owned as an ownedRelatedElement of the
+                //implied TypeFeaturing relationship. For further details, see 8.4.4.3 .
+                ILibraryNamespaceProvider nsProvider = LibraryNamespaceProvider.getFrom(this);
+                if (nsProvider == null) {
+                    nsProvider = new LibraryNamespaceProvider(this);
+                }
+                Type snapshot = nsProvider.getNamespaceFromLibrary("Occurrences::Occurrence::snapshot", Type.class);
+                if (owningType == nsProvider.getNamespaceFromLibrary("Occurrences::Occurrence")) {
+                    implicitType = snapshot;
+                } else {
+                    implicitType = SysmlFactory.eINSTANCE.createFeature();
+                    typeFeaturing.getOwnedRelatedElement().add(implicitType);
+
+                    Specialization specialization = SysmlFactory.eINSTANCE.createSpecialization();
+                    implicitType.getOwnedRelationship().add(specialization);
+                    specialization.setSpecific(implicitType);
+                    specialization.setGeneral(snapshot);
+                }
+
+                typeFeaturing.setFeaturingType(owningType);
+                typeFeaturing.setFeatureOfType((Feature) implicitType);
+                implicitType.getOwnedRelationship().add(typeFeaturing);
+
+            }
+
+        }
+        return implicitType;
+    }
 } // FeatureImpl

backend/metamodel/syson-sysml-metamodel/src/test/java/org/eclipse/syson/sysml/impl/FeatureImplTest.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2024 Obeo.
+ * Copyright (c) 2024, 2026 Obeo.
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v2.0
  * which accompanies this distribution, and is available at
@@ -12,12 +12,16 @@
  *******************************************************************************/
 package org.eclipse.syson.sysml.impl;
 
-import static org.junit.Assert.assertNull;
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
 
 import org.eclipse.syson.sysml.Feature;
+import org.eclipse.syson.sysml.ItemDefinition;
+import org.eclipse.syson.sysml.ItemUsage;
 import org.eclipse.syson.sysml.util.ModelBuilder;
 import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 
 /**
@@ -59,4 +63,22 @@ public void testNames() {
         assertEquals("f", f2.effectiveShortName());
     }
 
+
+    @Test
+    @DisplayName("GIVEN a non variable feature in a Type, WHEN computing it's featuring types, THEN the owning type is returned")
+    public void checkImplicitFeaturingTypeNoVariableFeature() {
+        var itemDef = this.builder.createWithName(ItemDefinition.class, "ItemDef");
+        ItemUsage itemUsage = this.builder.createInWithName(ItemUsage.class, itemDef, "ItemUsage");
+        assertThat(itemUsage.getFeaturingType()).hasSize(1).allMatch(type -> type == itemDef);
+    }
+
+    @Test
+    @DisplayName("GIVEN a variable feature in a Type, WHEN computing it's featuring types, THEN the owning type is returned")
+    public void checkImplicitFeaturingTypeVariableFeature() {
+        var itemDef = this.builder.createWithName(ItemDefinition.class, "ItemDef");
+        ItemUsage itemUsage = this.builder.createInWithName(ItemUsage.class, itemDef, "ItemUsage");
+        itemUsage.setIsVariable(true);
+        assertThat(itemUsage.getFeaturingType()).hasSize(1)
+                .allMatch(type -> type instanceof Feature feature && feature.getFeaturingType().contains(itemDef));
+    }
 }

doc/content/modules/user-manual/pages/release-notes/2026.3.0.adoc

@@ -70,6 +70,14 @@ part system {
 
 ** `Req Id` and `Declared Short Name` properties of `RequirementDefinition` and `RequirementUsage` are now synchronized, as required by the SysMLv2 specification.
 
+* In _Validation_ view:
+
+** Improve the computation of _featuringType_ on `Feature` to avoid getting the following validation error:
++
+```
+If a Feature is owned via a FeatureMembership, then it must have a featuringType for which the operation isFeaturingType returns true. (checkFeatureFeatureMembershipTypeFeaturing constraint on Feature is not respected for Test::MyItemDef::myFeature)
+````
+
 == Improvements
 
 * In diagrams: