Bug 130976 [Viewers] Error is calculation of parent path when calling TreePathViewerSorter
There is an error in the parent path calculation in AbstractTreeViewer#getSortedChildren. If the input of the viewer is passed, a tee path of length one is passed to the sorter but a null should be passed (as mentioned in the method spec). I will attach a patch.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
for (int i = items.length; --i >= min;) {
            if (items[i].getData() != null) {
                disassociate(items[i]);
            }
            items[i].dispose();
        }
        
        
        
        
        
        
        
        for (int i = 0; i < min; ++i) {
            Item item = items[i];
            Object oldElement = item.getData();
            if (oldElement != null) {
                Object newElement = elementChildren[i];
                if (newElement != oldElement) {
                    if (equals(newElement, oldElement)) {
                        
                        
                        
                        
                    	Object data = item.getData();
                    	if (data != null) {
                    		unmapElement(data, item);
                    	}