From 59a14b7c9d448f239400c58e7db177597c26c216 Mon Sep 17 00:00:00 2001
From: Oliver Tonnhofer <olt@bogosoft.com>
Date: Fri, 8 Nov 2013 15:07:42 +0100
Subject: [PATCH] remove skipped nodes before accessing first ID; skip empty
 node lists

---
 cache/delta.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/cache/delta.go b/cache/delta.go
index fa478dc..5c9a98f 100644
--- a/cache/delta.go
+++ b/cache/delta.go
@@ -220,10 +220,14 @@ func removeSkippedNodes(nodes []element.Node) []element.Node {
 // nodes need to be sorted by Id.
 func (self *DeltaCoordsCache) PutCoords(nodes []element.Node) error {
 	var start, currentBunchId int64
+	nodes = removeSkippedNodes(nodes)
+	if len(nodes) == 0 {
+		// skipped all nodes
+		return nil
+	}
 	currentBunchId = self.getBunchId(nodes[0].Id)
 	start = 0
 	totalNodes := len(nodes)
-	nodes = removeSkippedNodes(nodes)
 	for i, node := range nodes {
 		bunchId := self.getBunchId(node.Id)
 		if bunchId != currentBunchId {