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
continue;
				}
				if(treePath.equals(getTreePathFromItem((Item) candidate), getComparer())) {
					return candidate;
				}
			}
			return null;
		}
		return findItem(elementOrTreePath);
	}
    /**
     * Recursively expands the subtree rooted at the given widget to the given
     * level.
     * <p>
     * </p>
     * Note that the default implementation of this method does not call <code>setRedraw</code>.
     * 
     * @param widget
     *           the widget
     * @param level
     *           non-negative level, or <code>ALL_LEVELS</code> to collapse
     *           all levels of the tree
     */
    protected void internalExpandToLevel(Widget widget, int level) {
        if (level == ALL_LEVELS || level > 0) {
    		createChildren(widget);
            if (widget instanceof Item) {
				setExpanded((Item) widget, true);
			}
            if (level == ALL_LEVELS || level > 1) {