ST6RI-941 NPE when evaluating derived properties on feature chains

org.omg.sysml.logic/src/main/java/org/omg/sysml/util/TypeUtil.java

@@ -1,7 +1,8 @@
 /*******************************************************************************
  * SysML 2 Pilot Implementation
  * Copyright (c) 2021-2022, 2024-2026 Model Driven Solutions, Inc.
- *    
+ * Copyright (c) 2026 Obeo
+ *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the Eclipse Public License as published by
  * the Eclipse Foundation, version 2 of the License.
@@ -228,6 +229,9 @@ public static List<Feature> getOwnedParametersOf(Type type) {
 		if (type instanceof Feature) {
 			type = FeatureUtil.getBasicFeatureOf((Feature)type);
 		}
+		if (type == null) {
+			return new ArrayList<>();
+		}
 		return type.getOwnedFeature().stream().
 				filter(FeatureUtil::isParameter).
 				collect(Collectors.toList());

org.omg.sysml.logic/src/test/java/org/omg/sysml/logic/TypeUtilTest.java

@@ -0,0 +1,51 @@
+/*******************************************************************************
+ * SysML 2 Pilot Implementation
+ * Copyright (c) 2026 Obeo
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the Eclipse Public License as published by
+ * the Eclipse Foundation, version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * Eclipse Public License for more details.
+ *
+ * You should have received a copy of theEclipse Public License
+ * along with this program. If not, see <https://www.eclipse.org/legal/epl-2.0/>.
+ *  
+ * @license EPL-2.0 <http://spdx.org/licenses/EPL-2.0>
+ *
+ *******************************************************************************/
+
+package org.omg.sysml.logic;
+
+import static org.junit.Assert.assertNull;
+
+import org.junit.Test;
+import org.omg.sysml.lang.sysml.AssignmentActionUsage;
+import org.omg.sysml.lang.sysml.FeatureChaining;
+import org.omg.sysml.lang.sysml.SysMLFactory;
+
+/**
+ * Tests utility behavior reached from SysML derived properties.
+ */
+public class TypeUtilTest {
+
+	/**
+	 * Derived properties on some feature-like SysML elements ask TypeUtil for
+	 * owned parameters. When the feature is a chain whose target has not been
+	 * linked yet, the basic feature is null and the derivation must simply see no
+	 * parameters.
+	 */
+	@Test
+	public void derivedPropertyHandlesUnresolvedChainedFeatureWithoutParameters() {
+		SysMLLogicStandaloneSetup.doSetup();
+
+		AssignmentActionUsage assignment = SysMLFactory.eINSTANCE.createAssignmentActionUsage();
+		FeatureChaining unresolvedChaining = SysMLFactory.eINSTANCE.createFeatureChaining();
+		assignment.getOwnedRelationship().add(unresolvedChaining);
+
+		assertNull(assignment.getValueExpression());
+	}
+}