From 251d504d40ed9111f7ef62e116e810f62c050966 Mon Sep 17 00:00:00 2001
From: Radu Ioan Fericean <radu@fericean.ro>
Date: Wed, 23 Apr 2014 13:23:58 +0300
Subject: [PATCH] fix for callcost out of bounds merge (thanks DigiDaz)

---
 engine/callcost.go      |  2 +-
 engine/callcost_test.go | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/engine/callcost.go b/engine/callcost.go
index dff4be5c5..3dd1a4aab 100644
--- a/engine/callcost.go
+++ b/engine/callcost.go
@@ -46,7 +46,7 @@ type CallCost struct {
 
 // Merges the received timespan if they are similar (same activation period, same interval, same minute info.
 func (cc *CallCost) Merge(other *CallCost) {
-	if len(cc.Timespans)-1 < 0 {
+	if len(cc.Timespans)-1 < 0 || len(other.Timespans) == 0 {
 		return
 	}
 	ts := cc.Timespans[len(cc.Timespans)-1]
diff --git a/engine/callcost_test.go b/engine/callcost_test.go
index 0b9919d0e..5b8fa78e2 100644
--- a/engine/callcost_test.go
+++ b/engine/callcost_test.go
@@ -125,6 +125,18 @@ func TestMultipleInputRightMerge(t *testing.T) {
 	}
 }
 
+func TestCallCostMergeEmpty(t *testing.T) {
+	t1 := time.Date(2012, time.February, 2, 17, 58, 0, 0, time.UTC)
+	t2 := time.Date(2012, time.February, 2, 17, 59, 0, 0, time.UTC)
+	cd := &CallDescriptor{Direction: OUTBOUND, TOR: "0", Tenant: "vdf", Subject: "rif", Destination: "0256", TimeStart: t1, TimeEnd: t2}
+	cc1, _ := cd.GetCost()
+	cc2 := &CallCost{}
+	cc1.Merge(cc2)
+	if len(cc1.Timespans) != 1 {
+		t.Error("Error mergin empty call cost: ", len(cc1.Timespans))
+	}
+}
+
 func TestCallCostGetDurationZero(t *testing.T) {
 	cc := &CallCost{}
 	if cc.GetDuration().Seconds() != 0 {