From 3c926a6758998203ece298d0381001ebe2eda6f2 Mon Sep 17 00:00:00 2001
From: David Julien <juliendavid90@gmail.com>
Date: Wed, 26 Jul 2017 17:08:39 -0400
Subject: [PATCH] fixed CurrentBlockReward bug and created current block reward
 test

---
 consensus/current.go      |  5 +++--
 consensus/current_test.go | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/consensus/current.go b/consensus/current.go
index 76a788f..2a108ee 100644
--- a/consensus/current.go
+++ b/consensus/current.go
@@ -1,6 +1,7 @@
 package consensus
 
 import (
+	"math"
 	"math/big"
 
 	"github.com/ubclaunchpad/cumulus/blockchain"
@@ -24,8 +25,8 @@ var (
 // CurrentBlockReward determines the current block reward using the
 // the length of the blockchain
 func CurrentBlockReward(bc *blockchain.BlockChain) uint64 {
-	return StartingBlockReward /
-		uint64(((len(bc.Blocks) / blockRewardHalvingRate) + 1))
+	timesHalved := float64((len(bc.Blocks) / blockRewardHalvingRate))
+	return StartingBlockReward / uint64(math.Pow(float64(2), timesHalved))
 }
 
 // CurrentTarget returns the current target based on the CurrentDifficulty
diff --git a/consensus/current_test.go b/consensus/current_test.go
index efb9de6..4147ef9 100644
--- a/consensus/current_test.go
+++ b/consensus/current_test.go
@@ -12,3 +12,22 @@ func TestCurrentTarget(t *testing.T) {
 		t.Fail()
 	}
 }
+
+func TestCurrentBlockReward(t *testing.T) {
+	bc, _ := blockchain.NewValidBlockChainFixture()
+	if CurrentBlockReward(bc) != StartingBlockReward {
+		t.Fail()
+	}
+	for i := len(bc.Blocks); i < blockRewardHalvingRate; i++ {
+		bc.AppendBlock(new(blockchain.Block))
+	}
+	if CurrentBlockReward(bc) != StartingBlockReward/2 {
+		t.Fail()
+	}
+	for i := 0; i < blockRewardHalvingRate; i++ {
+		bc.AppendBlock(new(blockchain.Block))
+	}
+	if CurrentBlockReward(bc) != StartingBlockReward/4 {
+		t.Fail()
+	}
+}