[1567] Fix Sub-parts are not displayed inside Package nodes

CHANGELOG.adoc

@@ -85,6 +85,8 @@ Now it has been fixed in Sirius Web 2025.8.4, `SysONUpdateLibraryExecutor` has b
 - https://github.com/eclipse-syson/syson/issues/1546[#1546] [diagrams] Fix drag and drop of a graphical node from the diagram background into a _Package_ graphical node.
 - https://github.com/eclipse-syson/syson/issues/1550[#1550] [diagrams] Fix an issue where the _action flow_ compartment was not revealed when the _New Start Action_ was executed.
 - https://github.com/eclipse-syson/syson/issues/1547[#1547] [diagrams] Fix an issue where the _Delete from diagram_ action did nothing on elements inside a _Package_ in diagrams.
+- https://github.com/eclipse-syson/syson/issues/1567[#1567] [diagrams] Fix an issue where a `PartUsage` contained in a `PartUsage` contained in a `Package` was not displayed, even though it was exposed in the `ViewUsage` corresponding to the diagram.
+`PartUsage` is just one example, but the same issue could appear with any other `Element` contained in `Element` contained in a `Package`.
 
 === Improvements
 

backend/application/syson-application/src/test/java/org/eclipse/syson/application/controllers/diagrams/general/view/GVDropFromDiagramTests.java

@@ -75,7 +75,7 @@ public void beforeEach() {
         this.givenInitialServerState.initialize();
     }
 
-    @DisplayName("Given a diagram with some nodes, when a node is dropped in another one, then the diagram is updated")
+    @DisplayName("GIVEN a diagram with some nodes, WHEN a node is dropped in another one, THEN the diagram is updated")
     @Sql(scripts = { GeneralViewWithTopNodesTestProjectData.SCRIPT_PATH }, executionPhase = Sql.ExecutionPhase.BEFORE_TEST_METHOD,
             config = @SqlConfig(transactionMode = SqlConfig.TransactionMode.ISOLATED))
     @Sql(scripts = { "/scripts/cleanup.sql" }, executionPhase = Sql.ExecutionPhase.AFTER_TEST_METHOD, config = @SqlConfig(transactionMode = SqlConfig.TransactionMode.ISOLATED))

backend/application/syson-application/src/test/java/org/eclipse/syson/application/controllers/diagrams/general/view/GVPackageTests.java

@@ -0,0 +1,161 @@
+/*******************************************************************************
+ * Copyright (c) 2025 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
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Obeo - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.syson.application.controllers.diagrams.general.view;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.eclipse.sirius.components.diagrams.tests.DiagramEventPayloadConsumer.assertRefreshedDiagramThat;
+
+import java.time.Duration;
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Consumer;
+
+import org.eclipse.sirius.components.collaborative.diagrams.dto.DiagramEventInput;
+import org.eclipse.sirius.components.collaborative.diagrams.dto.DiagramRefreshedEventPayload;
+import org.eclipse.sirius.components.diagrams.tests.navigation.DiagramNavigator;
+import org.eclipse.sirius.components.view.emf.diagram.IDiagramIdProvider;
+import org.eclipse.sirius.web.tests.services.api.IGivenInitialServerState;
+import org.eclipse.syson.AbstractIntegrationTests;
+import org.eclipse.syson.application.controllers.diagrams.testers.ToolTester;
+import org.eclipse.syson.application.data.GeneralViewWithTopNodesTestProjectData;
+import org.eclipse.syson.services.diagrams.DiagramDescriptionIdProvider;
+import org.eclipse.syson.services.diagrams.api.IGivenDiagramDescription;
+import org.eclipse.syson.services.diagrams.api.IGivenDiagramSubscription;
+import org.eclipse.syson.standard.diagrams.view.SDVDescriptionNameGenerator;
+import org.eclipse.syson.sysml.SysmlPackage;
+import org.eclipse.syson.util.IDescriptionNameGenerator;
+import org.eclipse.syson.util.SysONRepresentationDescriptionIdentifiers;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.jdbc.Sql;
+import org.springframework.test.context.jdbc.SqlConfig;
+import org.springframework.transaction.annotation.Transactional;
+
+import reactor.core.publisher.Flux;
+import reactor.test.StepVerifier;
+
+/**
+ * Tests the nodes inside the a PAckage nodes in the General View diagram.
+ *
+ * @author arichard
+ */
+@Transactional
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
+public class GVPackageTests extends AbstractIntegrationTests {
+
+    @Autowired
+    private IGivenInitialServerState givenInitialServerState;
+
+    @Autowired
+    private IGivenDiagramSubscription givenDiagramSubscription;
+
+    @Autowired
+    private IGivenDiagramDescription givenDiagramDescription;
+
+    @Autowired
+    private IDiagramIdProvider diagramIdProvider;
+
+    @Autowired
+    private ToolTester toolTester;
+
+    private final IDescriptionNameGenerator descriptionNameGenerator = new SDVDescriptionNameGenerator();
+
+    private Flux<DiagramRefreshedEventPayload> givenSubscriptionToDiagram() {
+        var diagramEventInput = new DiagramEventInput(UUID.randomUUID(),
+                GeneralViewWithTopNodesTestProjectData.EDITING_CONTEXT_ID,
+                GeneralViewWithTopNodesTestProjectData.GraphicalIds.DIAGRAM_ID);
+        var flux = this.givenDiagramSubscription.subscribe(diagramEventInput);
+        return flux;
+    }
+
+    @BeforeEach
+    public void beforeEach() {
+        this.givenInitialServerState.initialize();
+    }
+
+    @DisplayName("GIVEN a diagram with a Package node, WHEN a Part node and a Sub-Part node are created, THEN the Part node and the Sub-Part node are visible inside the Package, on the same level, with an edge between them")
+    @Sql(scripts = { GeneralViewWithTopNodesTestProjectData.SCRIPT_PATH }, executionPhase = Sql.ExecutionPhase.BEFORE_TEST_METHOD,
+            config = @SqlConfig(transactionMode = SqlConfig.TransactionMode.ISOLATED))
+    @Sql(scripts = { "/scripts/cleanup.sql" }, executionPhase = Sql.ExecutionPhase.AFTER_TEST_METHOD, config = @SqlConfig(transactionMode = SqlConfig.TransactionMode.ISOLATED))
+    @Test
+    public void testCreateSubPartInPackage() {
+        var flux = this.givenSubscriptionToDiagram();
+
+        var diagramDescription = this.givenDiagramDescription.getDiagramDescription(GeneralViewWithTopNodesTestProjectData.EDITING_CONTEXT_ID,
+                SysONRepresentationDescriptionIdentifiers.GENERAL_VIEW_DIAGRAM_DESCRIPTION_ID);
+        var diagramDescriptionIdProvider = new DiagramDescriptionIdProvider(diagramDescription, this.diagramIdProvider);
+
+        var newPartToolId = diagramDescriptionIdProvider.getNodeCreationToolId(this.descriptionNameGenerator.getNodeName(SysmlPackage.eINSTANCE.getPackage()), "New Part");
+        assertThat(newPartToolId).as("The tool 'New Part' should exist on the Package").isNotNull();
+
+        var newSubPartToolId = diagramDescriptionIdProvider.getNodeCreationToolId(this.descriptionNameGenerator.getNodeName(SysmlPackage.eINSTANCE.getPartUsage()), "New Part");
+        assertThat(newPartToolId).as("The tool 'New Part' should exist on the PartUsage").isNotNull();
+
+        var diagramId = new AtomicReference<String>();
+        var packageNodeId = new AtomicReference<String>();
+        var partNodeId = new AtomicReference<String>();
+
+        Consumer<Object> initialDiagramContentConsumer = assertRefreshedDiagramThat(diag -> {
+            diagramId.set(diag.getId());
+
+            var packageNode = new DiagramNavigator(diag).nodeWithLabel("Package").getNode();
+            packageNodeId.set(packageNode.getId());
+
+            assertThat(packageNode.getChildNodes()).hasSize(0);
+
+            assertThat(new DiagramNavigator(diag).findDiagramEdgeCount()).isEqualTo(3);
+
+        });
+
+        Runnable newPartUsageTool = () -> this.toolTester.invokeTool(GeneralViewWithTopNodesTestProjectData.EDITING_CONTEXT_ID, diagramId.get(), packageNodeId.get(), newPartToolId,
+                List.of());
+
+        Consumer<Object> updatedDiagramContentConsumerAfterNewPart = assertRefreshedDiagramThat(diag -> {
+            var packageNode = new DiagramNavigator(diag).nodeWithLabel("Package").getNode();
+
+            var partNode = new DiagramNavigator(diag).nodeWithLabel("Package").childNodeWithLabel("\u00ABpart\u00BB\npart1").getNode();
+            partNodeId.set(partNode.getId());
+
+            assertThat(packageNode.getChildNodes()).hasSize(1);
+            assertThat(packageNode.getChildNodes().get(0)).isEqualTo(partNode);
+
+            assertThat(new DiagramNavigator(diag).findDiagramEdgeCount()).isEqualTo(3);
+
+        });
+
+        Runnable newSubPartUsageTool = () -> this.toolTester.invokeTool(GeneralViewWithTopNodesTestProjectData.EDITING_CONTEXT_ID, diagramId.get(), partNodeId.get(), newSubPartToolId,
+                List.of());
+
+        Consumer<Object> updatedDiagramContentConsumerAfterNewSubPart = assertRefreshedDiagramThat(diag -> {
+            var packageNode = new DiagramNavigator(diag).nodeWithLabel("Package").getNode();
+
+            assertThat(packageNode.getChildNodes()).hasSize(2);
+
+            // a new edge exists between the Part and the sub-Part inside the Package node
+            assertThat(new DiagramNavigator(diag).findDiagramEdgeCount()).isEqualTo(4);
+        });
+
+        StepVerifier.create(flux)
+                .consumeNextWith(initialDiagramContentConsumer)
+                .then(newPartUsageTool)
+                .consumeNextWith(updatedDiagramContentConsumerAfterNewPart)
+                .then(newSubPartUsageTool)
+                .consumeNextWith(updatedDiagramContentConsumerAfterNewSubPart)
+                .thenCancel()
+                .verify(Duration.ofSeconds(10));
+    }
+}

backend/releng/syson-test-coverage/pom.xml

@@ -90,6 +90,11 @@
 			<artifactId>syson-sysml-validation</artifactId>
 			<version>2025.8.9</version>
 		</dependency>
+		<dependency>
+			<groupId>org.eclipse.syson</groupId>
+			<artifactId>syson-common-view</artifactId>
+			<version>2025.8.9</version>
+		</dependency>
 		<dependency>
 			<groupId>org.eclipse.syson</groupId>
 			<artifactId>syson-diagram-common-view</artifactId>

backend/views/syson-diagram-common-view/src/main/java/org/eclipse/syson/diagram/common/view/services/ViewFilterSwitch.java

@@ -22,6 +22,7 @@
 import org.eclipse.syson.sysml.AttributeUsage;
 import org.eclipse.syson.sysml.Documentation;
 import org.eclipse.syson.sysml.Element;
+import org.eclipse.syson.sysml.Namespace;
 import org.eclipse.syson.sysml.NamespaceImport;
 import org.eclipse.syson.sysml.Package;
 import org.eclipse.syson.sysml.PortUsage;
@@ -75,13 +76,13 @@ public ViewFilterSwitch(ViewDefinitionKind kind, List<Element> exposedElements,
     public Boolean defaultCase(EObject object) {
         Boolean displayAsTreeNode = Boolean.FALSE;
         if (ViewDefinitionKind.isGeneralView(this.kind)) {
-            displayAsTreeNode = Boolean.TRUE;
+            displayAsTreeNode = this.parentElement == null || (this.isDirectNestedNode(object));
         } else if (ViewDefinitionKind.isActionFlowView(this.kind)) {
             displayAsTreeNode = object instanceof ActionUsage || object instanceof ActionDefinition;
         } else if (ViewDefinitionKind.isStateTransitionView(this.kind)) {
             displayAsTreeNode = object instanceof StateUsage || object instanceof StateDefinition;
         } else {
-            displayAsTreeNode = !this.isNestedNode(object);
+            displayAsTreeNode = !this.isIndirectNestedNode(object);
         }
         return displayAsTreeNode;
     }
@@ -90,7 +91,7 @@ public Boolean defaultCase(EObject object) {
     public Boolean caseAttributeUsage(AttributeUsage object) {
         // For AttributeUsages we don't want nested Nodes, no matter the type of ViewDefinition.
         // The sub AttributeUsages are displayed in a compartment list called "attributes".
-        return !this.isNestedNode(object) && !ViewDefinitionKind.isActionFlowView(this.kind) && !ViewDefinitionKind.isStateTransitionView(this.kind);
+        return !this.isIndirectNestedNode(object) && !ViewDefinitionKind.isActionFlowView(this.kind) && !ViewDefinitionKind.isStateTransitionView(this.kind);
     }
 
     @Override
@@ -103,18 +104,51 @@ public Boolean caseDocumentation(Documentation object) {
     public Boolean casePortUsage(PortUsage object) {
         // For PortUsages we don't want nested Nodes, no matter the type of ViewDefinition.
         // The sub PortUsages are displayed in a compartment list called "ports" and/or as border nodes.
-        return !this.isNestedNode(object) && !ViewDefinitionKind.isActionFlowView(this.kind) && !ViewDefinitionKind.isStateTransitionView(this.kind);
+        return !this.isIndirectNestedNode(object) && !ViewDefinitionKind.isActionFlowView(this.kind) && !ViewDefinitionKind.isStateTransitionView(this.kind);
     }
 
-    private boolean isNestedNode(EObject object) {
-        boolean isNestedNode = false;
-        for (Element exposedElement : this.exposedElements) {
-            isNestedNode = !Objects.equals(exposedElement, object) && (this.parentElement == null && EMFUtils.isAncestor(exposedElement, object));
-            if (isNestedNode) {
-                break;
+    /**
+     * Check if the given object is an indirect nested node of the parentElement of this class.
+     *
+     * @param object
+     *            the given object
+     * @return <code>true</code> if the given object is an indirect node of the parentElement of this class,
+     *         <code>false</code> otherwise.
+     */
+    private boolean isIndirectNestedNode(EObject object) {
+        boolean isDirectNestedNode = false;
+        if (this.parentElement instanceof Namespace elt && !elt.getOwnedMember().contains(object)) {
+            isDirectNestedNode = true;
+        } else {
+            for (Element exposedElement : this.exposedElements) {
+                if (Objects.equals(exposedElement, object)) {
+                    continue;
+                } else if (this.parentElement == null && EMFUtils.isAncestor(exposedElement, object)) {
+                    isDirectNestedNode = true;
+                }
+                if (isDirectNestedNode) {
+                    break;
+                }
             }
         }
-        return isNestedNode;
+        return isDirectNestedNode;
     }
 
+    /**
+     * Check if the given object is a direct nested node of the parentElement of this class.
+     *
+     * @param object
+     *            the given object
+     * @return <code>true</code> if the given object is a direct nested node of the parentElement of this class,
+     *         <code>false</code> otherwise.
+     */
+    private boolean isDirectNestedNode(EObject object) {
+        boolean isDirectNestedNode = false;
+        if (this.parentElement instanceof Namespace elt && elt.getOwnedMember().contains(object)) {
+            isDirectNestedNode = true;
+        } else if (this.parentElement instanceof Package) {
+            isDirectNestedNode = true;
+        }
+        return isDirectNestedNode;
+    }
 }

backend/views/syson-diagram-common-view/src/main/java/org/eclipse/syson/diagram/common/view/services/ViewNodeService.java

@@ -137,7 +137,7 @@ public List<Element> getExposedElements(Element element, Element parent, EClass
                 exposedElements.addAll(viewUsage.getExposedElement());
             }
             var filteredExposedElements = exposedElements.stream()
-                    .filter(elt -> elt != null && Objects.equals(elt.eClass(), domainType) && (parent == null || parent.getOwnedElement().contains(elt)))
+                    .filter(elt -> this.isTypeOf(elt, domainType) && (parent == null || (!Objects.equals(parent, elt) && EMFUtils.isAncestor(parent, elt))))
                     .toList();
             elementsToExpose.addAll(filteredExposedElements);
             // if it is not a General View, we don't want to display nested nodes as tree (i.e. sibling nodes +
@@ -686,4 +686,18 @@ protected List<Object> getAncestors(Node selectedNode, Diagram diagram, IEditing
         }
         return ancestors;
     }
+
+    /**
+     * Check if the given {@link Element}'s {@link EClass} is the same than the given domainType.
+     *
+     * @param element
+     *            the given {@link Element}.
+     * @param domainType
+     *            the given domainType as an {@link EClass}.
+     * @return <code>true</code> if the given {@link Element}'s {@link EClass} is the same than the given domainType,
+     *         <code>false</code> otherwise.
+     */
+    protected boolean isTypeOf(Element element, EClass domainType) {
+        return element != null && Objects.equals(element.eClass(), domainType);
+    }
 }

doc/content/modules/user-manual/pages/release-notes/2025.10.0.adoc

@@ -76,6 +76,8 @@ Now it is only available on SysML model elements.
 - Fix drag and drop of a graphical node from the diagram background into a _Package_ graphical node.
 - Fix an issue where the _action flow_ compartment was not revealed when the _New Start Action_ was executed.
 - Fix an issue where the _Delete from diagram_ action did nothing on elements inside a _Package_ in diagrams.
+- Fix an issue where a `PartUsage` contained in a `PartUsage` contained in a `Package` was not displayed, even though it was exposed in the `ViewUsage` corresponding to the diagram.
+`PartUsage` is just one example, but the same issue could appear with any other `Element` contained in `Element` contained in a `Package`.
 
 == Improvements