Don't add SiblingOrder when specialising the first element of an archetype

tools/src/main/java/com/nedap/archie/diff/LCSOrderingDiff.java

@@ -128,7 +128,7 @@
 
         if(lcs.size() == 0) {
             //If there's no empty LCS, it's not possible to add sibling markers
-        }  else {
+        } else {
             for (int i = 0; i < childNodeIds.size(); i++) {
                 String nodeId = childNodeIds.get(i);
                 if (!nodeIdLCS.contains(nodeId)) {
@@ -192,26 +192,25 @@
         boolean onlyTheSameParentNodeId = false;
         String firstNodeIdWithSameParent = null;
 
-        for(int j = i - 1; j>= 0; j--) {
-
+        for(int j = i - 1; j >= 0; j--) {
             String otherNodeId = childNodeIds.get(j);
-            if(AOMUtils.getSpecializationDepthFromCode(nodeId) == childSpecializationDepth &&
+            if (AOMUtils.getSpecializationDepthFromCode(nodeId) == childSpecializationDepth &&
                     AOMUtils.codeExistsAtLevel(nodeId, childSpecializationDepth-1) &&
                     AOMUtils.codeAtLevel(otherNodeId, childSpecializationDepth-1).equals(AOMUtils.codeAtLevel(nodeId, childSpecializationDepth-1))) {
                 onlyTheSameParentNodeId = true;
                 firstNodeIdWithSameParent = otherNodeId;
             } else {
-                if (onlyTheSameParentNodeId) {
-                    CObject cObjectInResult = resultAttribute.getChild(nodeId);
-                    SiblingOrder order = DiffUtil.findSiblingOrder(siblingOrders, firstNodeIdWithSameParent);
-                    if(order != null) {
-                        DiffUtil.addSiblingOrder(siblingOrders, order, cObjectInResult);
-                    }
-                    return true;
-                }
-                return false;
+                break;
             }
+        }
 
+        if (onlyTheSameParentNodeId) {
+            CObject cObjectInResult = resultAttribute.getChild(nodeId);
+            SiblingOrder order = DiffUtil.findSiblingOrder(siblingOrders, firstNodeIdWithSameParent);
+            if(order != null) {
+                DiffUtil.addSiblingOrder(siblingOrders, order, cObjectInResult);
+            }
+            return true;
         }
         return false;
     }

tools/src/test/java/com/nedap/archie/diff/SiblingOrderDiffTest.java

@@ -61,5 +61,10 @@ public void redefinitionAtSamePlace() throws Exception {
         diffTestUtil.test("openEHR-EHR-CLUSTER.order-parent.v1.0.0.adls","openEHR-EHR-CLUSTER.redefinition_at_same_place.v1.0.0.adls");
     }
 
+    @Test
+    public void specialiseFirstElement() throws Exception {
+        diffTestUtil.test("openEHR-EHR-CLUSTER.order-parent.v1.0.0.adls","openEHR-EHR-CLUSTER.specialise_first_element.v1.0.0.adls");
+    }
+
     //The two tricky edge cases in the flattener test are really not interesting here, as the Differentiator will never create such hard to do code
 }

tools/src/test/resources/com/nedap/archie/diff/specexamples/openEHR-EHR-CLUSTER.lipid_studies_panel.adls

@@ -13,7 +13,6 @@ description
 definition
     CLUSTER[id1.1] matches {    -- Lipid studies panel
         items matches {
-            after [id3]
             CLUSTER[id3.1] matches {    -- LDL
                 items matches {
                     ELEMENT[id2.1] matches {    -- LDL cholesterol

tools/src/test/resources/com/nedap/archie/flattener/siblingorder/openEHR-EHR-CLUSTER.specialise_first_element.v1.0.0.adls

@@ -0,0 +1,44 @@
+archetype (adl_version=2.0.5; rm_release=1.0.2; generated)
+    openEHR-EHR-CLUSTER.specialise_first_element.v1.0.0
+
+specialize
+    openEHR-EHR-CLUSTER.order-parent.v1.0.0
+
+language
+	original_language = <[ISO_639-1::en]>
+
+description
+	lifecycle_state = <"unmanaged">
+
+definition
+    CLUSTER[id1.1] ∈ {
+        items ∈ {
+            ELEMENT[id2.1]
+        }
+}
+
+terminology
+	term_definitions = <
+		["en"] = <
+			["id1.1"] = <
+				text = <"cluster">
+				description = <"cluster">
+			>
+			["id0.1"] = <
+                text = <"item 5">
+                description = <"item 5">
+            >
+            ["id0.2"] = <
+                text = <"item 6">
+                description = <"item 6">
+            >
+            ["id0.3"] = <
+                text = <"item 7">
+                description = <"item 7">
+            >
+            ["id0.4"] = <
+                text = <"item 8">
+                description = <"item 8">
+            >
+        >
+	>