From 28c9ec2bd11925f0d432ee601c891ef234f8aaec Mon Sep 17 00:00:00 2001
From: Matt Joiner <anacrolix@gmail.com>
Date: Sat, 30 Apr 2016 11:07:29 +1000
Subject: [PATCH] Some changes to metainfo.InfoEx and testutil

---
 fs/torrentfs_test.go          |  7 ++-----
 internal/testutil/testutil.go | 37 ++++++++++++++++++-----------------
 metainfo/metainfo.go          | 14 +++++--------
 torrent.go                    |  2 +-
 4 files changed, 27 insertions(+), 33 deletions(-)

diff --git a/fs/torrentfs_test.go b/fs/torrentfs_test.go
index 187bb12e..688c7ac6 100644
--- a/fs/torrentfs_test.go
+++ b/fs/torrentfs_test.go
@@ -1,7 +1,6 @@
 package torrentfs
 
 import (
-	"bytes"
 	"fmt"
 	"io/ioutil"
 	"log"
@@ -73,10 +72,8 @@ func newGreetingLayout() (tl testLayout, err error) {
 	os.Mkdir(tl.Completed, 0777)
 	tl.MountDir = filepath.Join(tl.BaseDir, "mnt")
 	os.Mkdir(tl.MountDir, 0777)
-	name := testutil.CreateDummyTorrentData(tl.Completed)
-	metaInfoBuf := &bytes.Buffer{}
-	testutil.CreateMetaInfo(name, metaInfoBuf)
-	tl.Metainfo, err = metainfo.Load(metaInfoBuf)
+	testutil.CreateDummyTorrentData(tl.Completed)
+	tl.Metainfo = testutil.GreetingMetaInfo()
 	return
 }
 
diff --git a/internal/testutil/testutil.go b/internal/testutil/testutil.go
index b43ddffa..e9d21039 100644
--- a/internal/testutil/testutil.go
+++ b/internal/testutil/testutil.go
@@ -6,20 +6,25 @@
 package testutil
 
 import (
-	"bytes"
+	"crypto/sha1"
 	"fmt"
 	"io"
 	"io/ioutil"
 	"net/http"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"github.com/anacrolix/missinggo"
 
+	"github.com/anacrolix/torrent/bencode"
 	"github.com/anacrolix/torrent/metainfo"
 )
 
-const GreetingFileContents = "hello, world\n"
+const (
+	GreetingFileContents = "hello, world\n"
+	GreetingFileName     = "greeting"
+)
 
 func CreateDummyTorrentData(dirName string) string {
 	f, _ := os.Create(filepath.Join(dirName, "greeting"))
@@ -27,25 +32,23 @@ func CreateDummyTorrentData(dirName string) string {
 	f.WriteString(GreetingFileContents)
 	return f.Name()
 }
-
-// Writes to w, a metainfo containing the file at name.
-func CreateMetaInfo(name string, w io.Writer) {
-	var mi metainfo.MetaInfo
-	mi.Info.Name = filepath.Base(name)
-	fi, _ := os.Stat(name)
-	mi.Info.Length = fi.Size()
+func GreetingMetaInfo() (mi *metainfo.MetaInfo) {
+	mi = new(metainfo.MetaInfo)
+	mi.Info.Name = GreetingFileName
+	mi.Info.Length = int64(len(GreetingFileContents))
 	mi.Announce = "lol://cheezburger"
 	mi.Info.PieceLength = 5
 	err := mi.Info.GeneratePieces(func(metainfo.FileInfo) (io.ReadCloser, error) {
-		return os.Open(name)
+		return ioutil.NopCloser(strings.NewReader(GreetingFileContents)), nil
 	})
 	if err != nil {
 		panic(err)
 	}
-	err = mi.Write(w)
-	if err != nil {
-		panic(err)
-	}
+	mi.Info.Bytes, _ = bencode.Marshal(&mi.Info.Info)
+	h := sha1.New()
+	h.Write(mi.Info.Bytes)
+	missinggo.CopyExact(&mi.Info.Hash, h.Sum(nil))
+	return
 }
 
 // Gives a temporary directory containing the completed "greeting" torrent,
@@ -56,10 +59,8 @@ func GreetingTestTorrent() (tempDir string, metaInfo *metainfo.MetaInfo) {
 	if err != nil {
 		panic(err)
 	}
-	name := CreateDummyTorrentData(tempDir)
-	w := &bytes.Buffer{}
-	CreateMetaInfo(name, w)
-	metaInfo, _ = metainfo.Load(w)
+	CreateDummyTorrentData(tempDir)
+	metaInfo = GreetingMetaInfo()
 	return
 }
 
diff --git a/metainfo/metainfo.go b/metainfo/metainfo.go
index 3b2a04a2..d02bf3ca 100644
--- a/metainfo/metainfo.go
+++ b/metainfo/metainfo.go
@@ -183,8 +183,8 @@ func (info *Info) UpvertedFiles() []FileInfo {
 // important to Bittorrent.
 type InfoEx struct {
 	Info
-	Hash  *Hash
-	Bytes []byte
+	Hash  Hash   // Only set when unmarshalling or UpdateHash.
+	Bytes []byte // Only set when unmarshalling or UpdateBytes.
 }
 
 var (
@@ -193,21 +193,17 @@ var (
 )
 
 func (ie *InfoEx) UnmarshalBencode(data []byte) error {
-	ie.Bytes = append(make([]byte, 0, len(data)), data...)
+	ie.Bytes = append([]byte(nil), data...)
 	h := sha1.New()
 	_, err := h.Write(ie.Bytes)
 	if err != nil {
 		panic(err)
 	}
-	ie.Hash = new(Hash)
-	missinggo.CopyExact(ie.Hash, h.Sum(nil))
+	missinggo.CopyExact(&ie.Hash, h.Sum(nil))
 	return bencode.Unmarshal(data, &ie.Info)
 }
 
 func (ie InfoEx) MarshalBencode() ([]byte, error) {
-	if ie.Bytes != nil {
-		return ie.Bytes, nil
-	}
 	return bencode.Marshal(&ie.Info)
 }
 
@@ -244,6 +240,6 @@ func (mi *MetaInfo) Magnet() (m Magnet) {
 		}
 	}
 	m.DisplayName = mi.Info.Name
-	m.InfoHash = *mi.Info.Hash
+	m.InfoHash = mi.Info.Hash
 	return
 }
diff --git a/torrent.go b/torrent.go
index 849be74b..834b315d 100644
--- a/torrent.go
+++ b/torrent.go
@@ -224,7 +224,7 @@ func (t *Torrent) setMetadata(md *metainfo.Info, infoBytes []byte) (err error) {
 	t.info = &metainfo.InfoEx{
 		Info:  *md,
 		Bytes: infoBytes,
-		Hash:  &t.infoHash,
+		Hash:  t.infoHash,
 	}
 	t.storage, err = t.storageOpener.OpenTorrent(t.info)
 	if err != nil {
-- 
2.48.1