From bb9bc9205a888a688f15efe58f003fd5497db195 Mon Sep 17 00:00:00 2001
From: Olaoluwa Osuntokun <laolu32@gmail.com>
Date: Sat, 17 Jun 2017 00:41:42 +0200
Subject: [PATCH] htlcswitch: run all unit tests in parallel

---
 htlcswitch/queue_test.go  |  2 ++
 htlcswitch/switch_test.go |  8 ++++++++
 htlcswitch/test_utils.go  | 15 ++++++++++++++-
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/htlcswitch/queue_test.go b/htlcswitch/queue_test.go
index 91c18f4c..b317c075 100644
--- a/htlcswitch/queue_test.go
+++ b/htlcswitch/queue_test.go
@@ -13,6 +13,8 @@ import (
 // waiting queue, by executing methods in seprate goroutines which operates
 // with the same data.
 func TestWaitingQueueThreadSafety(t *testing.T) {
+	t.Parallel()
+
 	q := newWaitingQueue()
 
 	a := make([]btcutil.Amount, 1000)
diff --git a/htlcswitch/switch_test.go b/htlcswitch/switch_test.go
index a1df2dfd..6fe06234 100644
--- a/htlcswitch/switch_test.go
+++ b/htlcswitch/switch_test.go
@@ -30,6 +30,8 @@ var (
 // TestSwitchForward checks the ability of htlc switch to forward add/settle
 // requests.
 func TestSwitchForward(t *testing.T) {
+	t.Parallel()
+
 	var packet *htlcPacket
 
 	alicePeer := newMockServer(t, "alice")
@@ -106,6 +108,8 @@ func TestSwitchForward(t *testing.T) {
 // TestSwitchCancel checks that if htlc was rejected we remove unused
 // circuits.
 func TestSwitchCancel(t *testing.T) {
+	t.Parallel()
+
 	var request *htlcPacket
 
 	alicePeer := newMockServer(t, "alice")
@@ -180,6 +184,8 @@ func TestSwitchCancel(t *testing.T) {
 // TestSwitchAddSamePayment tests that we send the payment with the same
 // payment hash.
 func TestSwitchAddSamePayment(t *testing.T) {
+	t.Parallel()
+
 	var request *htlcPacket
 
 	alicePeer := newMockServer(t, "alice")
@@ -279,6 +285,8 @@ func TestSwitchAddSamePayment(t *testing.T) {
 // TestSwitchSendPayment tests ability of htlc switch to respond to the
 // users when response is came back from channel link.
 func TestSwitchSendPayment(t *testing.T) {
+	t.Parallel()
+
 	alicePeer := newMockServer(t, "alice")
 	aliceChannelLink := newMockChannelLink(chanID1, aliceChanID, alicePeer)
 
diff --git a/htlcswitch/test_utils.go b/htlcswitch/test_utils.go
index 214550c9..fbff7b10 100644
--- a/htlcswitch/test_utils.go
+++ b/htlcswitch/test_utils.go
@@ -315,7 +315,9 @@ type threeHopNetwork struct {
 	globalPolicy ForwardingPolicy
 }
 
-// generateHops...
+// generateHops creates the per hop payload, the total amount to be sent, and
+// also the time lock value needed to route a HTLC with the target amount over
+// the specified path.
 func generateHops(payAmt btcutil.Amount,
 	path ...*channelLink) (btcutil.Amount, uint32, []ForwardingInfo) {
 
@@ -328,19 +330,27 @@ func generateHops(payAmt btcutil.Amount,
 
 	hops := make([]ForwardingInfo, len(path))
 	for i := len(path) - 1; i >= 0; i-- {
+		// If this is the last hop, then the next hop is the special
+		// "exit node". Otherwise, we look to the "prior" hop.
 		nextHop := exitHop
 		if i != len(path)-1 {
 			nextHop = path[i+1].channel.ShortChanID()
 		}
 
+		// If this is the last, hop, then the time lock will be their
+		// specified delta policy.
 		timeLock := lastHop.cfg.FwrdingPolicy.TimeLockDelta
 		totalTimelock += timeLock
 
+		// Otherwise, the outgoing time lock should be the incoming
+		// timelock minus their specified delta.
 		if i != len(path)-1 {
 			delta := path[i].cfg.FwrdingPolicy.TimeLockDelta
 			timeLock = totalTimelock - delta
 		}
 
+		// Finally, we'll need to calculate the amount to forward. For
+		// the last hop, it's just the payment amount.
 		amount := payAmt
 		if i != len(path)-1 {
 			prevHop := hops[i+1]
@@ -349,6 +359,9 @@ func generateHops(payAmt btcutil.Amount,
 			fee := ExpectedFee(path[i].cfg.FwrdingPolicy, prevAmount)
 			runningAmt += fee
 
+			// If the this the first hop, then we don't need to
+			// apply any fee, otherwise, the amount to forward
+			// needs to take into account the fees.
 			if i == 0 {
 				amount = prevAmount
 			} else {