From 724915c0e9a8edfed584317a1764ab09d5be066a Mon Sep 17 00:00:00 2001
From: aeddi <antoine.e.b@gmail.com>
Date: Thu, 6 Jun 2019 17:03:47 +0200
Subject: [PATCH] fix: fix Difference with empty log

---
 log/log.go            | 12 ++++++------
 test/entry_io_test.go |  4 ----
 test/utils.go         |  4 ++++
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/log/log.go b/log/log.go
index 4cc3972..c2bc259 100644
--- a/log/log.go
+++ b/log/log.go
@@ -2,9 +2,7 @@ package log
 
 import (
 	"bytes"
-	"encoding/hex"
 	"encoding/json"
-	"fmt"
 	"sort"
 	"strconv"
 	"strings"
@@ -386,10 +384,12 @@ func (l *Log) Join(otherLog *Log, size int) (*Log, error) {
 }
 
 func Difference(logA, logB *Log) *entry.OrderedMap {
-	if logA == nil || logA.Entries == nil || len(logA.Entries.Keys()) == 0 {
-		return logB.Entries
-	} else if logB == nil || logB.Entries == nil || len(logB.Entries.Keys()) == 0 {
-		return logA.Entries
+	if logA == nil || logA.Entries == nil || logA.Entries.Len() == 0 || logB == nil {
+		return entry.NewOrderedMap()
+	}
+
+	if logB.Entries == nil {
+		logB.Entries = entry.NewOrderedMap()
 	}
 
 	stack := logA.heads.Keys()
diff --git a/test/entry_io_test.go b/test/entry_io_test.go
index 3f792da..7a2c38d 100644
--- a/test/entry_io_test.go
+++ b/test/entry_io_test.go
@@ -19,10 +19,6 @@ import (
 	. "github.com/smartystreets/goconvey/convey"
 )
 
-func intPtr(val int) *int {
-	return &val
-}
-
 func TestEntryPersistence(t *testing.T) {
 	_, cancel := context.WithTimeout(context.Background(), time.Second*10)
 	defer cancel()
diff --git a/test/utils.go b/test/utils.go
index 199ea62..b502db5 100644
--- a/test/utils.go
+++ b/test/utils.go
@@ -14,3 +14,7 @@ func minInt(a, b int) int {
 	}
 	return b
 }
+
+func intPtr(val int) *int {
+	return &val
+}