YELLOW

getModelElementAncestor():
 - Actually return null if levelsUp > depth(modelElement)
 - Additionally, also return null if levelsUp < 0
refs 2490

org.fortiss.tooling.kernel/trunk/src/org/fortiss/tooling/kernel/utils/EcoreUtils.java

@@ -55,7 +55,7 @@ import org.eclipse.emf.ecore.util.EcoreUtil.UsageCrossReferencer;
  * @author ratiu
  * @author $Author: hoelzl $
  * @version $Rev: 18709 $
- * @ConQAT.Rating YELLOW Hash: F0DBBD05D8DFBB7937EB53D25F86A65A
+ * @ConQAT.Rating YELLOW Hash: 4E50E2E5CCE10F860A7F387B0F593E41
  */
 public class EcoreUtils {
 
@@ -426,17 +426,18 @@ public class EcoreUtils {
 
 	/**
 	 * Returns the ancestor of the {@link EObject} {@code o} that is {@code levelsUp} levels above
-	 * model element in the hierarchy, or {@code null}, in case {@code levelsUp >
-	 * depth(modelElement)}.
+	 * model element in the hierarchy, or {@code null}, in case {@code levelsUp < 0} or
+	 * {@code levelsUp > depth(modelElement)}.
 	 */
 	public static EObject getModelElementAncestor(EObject o, int levelsUp) {
-		// FIXME (FH): this method never returns null (as stated in the comment)
+		if(levelsUp < 0) {
+			return null;
+		}
 		while(o.eContainer() != null && levelsUp > 0) {
 			o = o.eContainer();
 			levelsUp--;
 		}
-		return o;
-
+		return levelsUp == 0 ? o : null;
 	}
 
 	/**