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package main
import (
"context"
"strings"
"testing"
)
func TestBencodePrimitives(t *testing.T) {
t.Run("integer", func(t *testing.T) {
v, err := parseBencode([]byte("i42e"))
if err != nil {
t.Fatal(err)
}
if v.Int == nil || *v.Int != 42 {
t.Errorf("got %+v, want 42", v)
}
})
t.Run("negative integer", func(t *testing.T) {
v, err := parseBencode([]byte("i-7e"))
if err != nil {
t.Fatal(err)
}
if v.Int == nil || *v.Int != -7 {
t.Errorf("got %+v, want -7", v)
}
})
t.Run("byte string", func(t *testing.T) {
v, err := parseBencode([]byte("5:hello"))
if err != nil {
t.Fatal(err)
}
if string(v.Str) != "hello" {
t.Errorf("got %q, want hello", v.Str)
}
})
t.Run("empty byte string", func(t *testing.T) {
v, err := parseBencode([]byte("0:"))
if err != nil {
t.Fatal(err)
}
if v.Str == nil || len(v.Str) != 0 {
t.Errorf("got %+v, want an empty non-nil string", v)
}
})
t.Run("binary byte string", func(t *testing.T) {
// `pieces` is binary; a decoder that assumed UTF-8 would corrupt it.
data := append([]byte("4:"), 0x00, 0xff, 0x80, 0x01)
v, err := parseBencode(data)
if err != nil {
t.Fatal(err)
}
if len(v.Str) != 4 || v.Str[1] != 0xff {
t.Errorf("binary data was corrupted: % x", v.Str)
}
})
t.Run("list", func(t *testing.T) {
v, err := parseBencode([]byte("li1ei2ee"))
if err != nil {
t.Fatal(err)
}
if len(v.List) != 2 {
t.Fatalf("got %+v, want 2 elements", v.List)
}
})
t.Run("empty list", func(t *testing.T) {
v, err := parseBencode([]byte("le"))
if err != nil {
t.Fatal(err)
}
if v.List == nil || len(v.List) != 0 {
t.Errorf("got %+v, want an empty non-nil list", v)
}
})
t.Run("dict", func(t *testing.T) {
v, err := parseBencode([]byte("d3:foo3:bare"))
if err != nil {
t.Fatal(err)
}
if string(v.Dict["foo"].Str) != "bar" {
t.Errorf("got %+v", v.Dict)
}
})
t.Run("nested", func(t *testing.T) {
v, err := parseBencode([]byte("d4:infod4:name3:foo5:filesleee"))
if err != nil {
t.Fatal(err)
}
info := v.Dict["info"]
if info.Dict == nil || string(info.Dict["name"].Str) != "foo" {
t.Errorf("got %+v", v)
}
})
}
func TestBencodeRejectsMalformed(t *testing.T) {
for _, in := range []string{
"", // empty
"i42", // unterminated integer
"ixe", // not a number
"5:abc", // string shorter than its length
"-1:x", // negative length
"l i1e", // unterminated list
"d3:fooe", // dict key without a value
"di1ei2ee", // non-string dict key
"i1ei2e", // trailing data
"x", // unknown type
"999999999:ab", // length beyond input
} {
if _, err := parseBencode([]byte(in)); err == nil {
t.Errorf("parseBencode(%q) should have failed", in)
}
}
}
func TestParseTorrentFileMultiFile(t *testing.T) {
// A minimal but realistic multi-file torrent.
data := []byte("d" +
"8:announce20:https://example.org/" +
"13:creation datei1600000000e" +
"4:infod" +
"5:filesl" +
"d6:lengthi100e4:pathl9:01 a.flacee" +
"d6:lengthi200e4:pathl3:art5:c.jpgee" +
"e" +
"4:name9:The Album" +
"12:piece lengthi262144e" +
"6:pieces4:aaaa" +
"7:privatei1e" +
"e" +
"e")
tf, err := parseTorrentFile(data)
if err != nil {
t.Fatal(err)
}
if tf.Announce != "https://example.org/" {
t.Errorf("announce = %q", tf.Announce)
}
if tf.Info.Name != "The Album" {
t.Errorf("name = %q", tf.Info.Name)
}
if len(tf.Info.Files) != 2 {
t.Fatalf("got %d files, want 2", len(tf.Info.Files))
}
if tf.Info.Files[0].Length != 100 {
t.Errorf("length = %d, want 100", tf.Info.Files[0].Length)
}
// Nested paths must keep their components, since they are joined against
// the torrent name to address the file on disk.
if len(tf.Info.Files[1].Path) != 2 || tf.Info.Files[1].Path[0] != "art" {
t.Errorf("path = %v, want [art c.jpg]", tf.Info.Files[1].Path)
}
if tf.Info.PieceLength != 262144 {
t.Errorf("piece length = %d", tf.Info.PieceLength)
}
if tf.Info.Private == nil || !*tf.Info.Private {
t.Error("private should be true")
}
if tf.CreationDate == nil || tf.CreationDate.Unix() != 1600000000 {
t.Errorf("creation date = %v", tf.CreationDate)
}
// The path used to fetch the file must include the torrent directory.
if got := torrentEntryPath(tf, tf.Info.Files[1]); got != "The Album/art/c.jpg" {
t.Errorf("torrentEntryPath = %q", got)
}
}
func TestParseTorrentFileSingleFile(t *testing.T) {
data := []byte("d8:announce4:http4:infod6:lengthi500e4:name7:one.mp3" +
"12:piece lengthi16384e6:pieces4:bbbbee")
tf, err := parseTorrentFile(data)
if err != nil {
t.Fatal(err)
}
if len(tf.Info.Files) != 1 {
t.Fatalf("got %d files, want 1 synthesised entry", len(tf.Info.Files))
}
if tf.Info.Files[0].Length != 500 || tf.Info.Files[0].Path[0] != "one.mp3" {
t.Errorf("got %+v", tf.Info.Files[0])
}
}
func TestLenientText(t *testing.T) {
// Torrent file names are often in a legacy encoding; they must not cause a
// decode failure.
got := lenientText([]byte{0xff, 0xfe, 'a'})
if !strings.HasSuffix(got, "a") {
t.Errorf("lenientText mangled the valid part: %q", got)
}
if lenientText(nil) != "" {
t.Error("nil should decode to the empty string")
}
}
func TestCoverArtPriority(t *testing.T) {
// Conventional names beat everything.
if got := findCoverArtInDirectory([]string{"back.jpg", "cover.jpg", "scan.png"}); got != "cover.jpg" {
t.Errorf("got %q, want cover.jpg", got)
}
// "front" beats a bare "cover" mention.
if got := findCoverArtInDirectory([]string{"albumcover.jpg", "cover-front.jpg"}); got != "cover-front.jpg" {
t.Errorf("got %q, want cover-front.jpg", got)
}
// Any image is better than none.
if got := findCoverArtInDirectory([]string{"booklet.png"}); got != "booklet.png" {
t.Errorf("got %q, want booklet.png", got)
}
// Non-images are not cover art.
if got := findCoverArtInDirectory([]string{"01.flac", "info.txt"}); got != "" {
t.Errorf("got %q, want no cover art", got)
}
// Case does not matter.
if got := findCoverArtInDirectory([]string{"COVER.JPG"}); got != "COVER.JPG" {
t.Errorf("got %q", got)
}
}
func TestFindAudioFiles(t *testing.T) {
files := []torrentFileEntry{
{Path: []string{"cover.jpg"}},
{Path: []string{"01 - song.FLAC"}},
{Path: []string{"notes.txt"}},
{Path: []string{"disc2", "02 - song.mp3"}},
}
audio := findAudioFiles(files)
if len(audio) != 2 {
t.Fatalf("got %d audio files, want 2", len(audio))
}
// The index must be the position in the full file list, because it is the
// file id used by the streaming endpoint.
if audio[0].Index != 1 || audio[1].Index != 3 {
t.Errorf("indices = %d, %d; want 1, 3", audio[0].Index, audio[1].Index)
}
}
func TestPercentage(t *testing.T) {
for _, c := range []struct {
in float64
want int
}{
{0, 0},
{1, 100},
{0.5, 50},
{0.001, 1}, // any progress at all must not display as 0%
{0.999, 100}, // ...but rounding up must not exceed 100
{-1, 0},
{2, 100},
} {
if got := percentage(c.in); got != c.want {
t.Errorf("percentage(%v) = %d, want %d", c.in, got, c.want)
}
}
}
// TestBencodeAgainstRealTorrents decodes every .torrent stored in the
// development database.
//
// This is the real test of the decoder: these files were produced by the
// tracker and include the encoding quirks that synthetic tests do not have.
func TestBencodeAgainstRealTorrents(t *testing.T) {
ctx := context.Background()
pool, err := connectDB(ctx, devDSN(t))
if err != nil {
t.Fatal(err)
}
defer pool.Close()
rows, err := pool.Query(ctx, `
SELECT torrent_id, torrent_file
FROM redacted.torrents_json
WHERE torrent_file IS NOT NULL`)
if err != nil {
t.Fatal(err)
}
defer rows.Close()
var checked, withCover, withAudio int
for rows.Next() {
var id int
var raw []byte
if err := rows.Scan(&id, &raw); err != nil {
t.Fatal(err)
}
tf, err := parseTorrentFile(raw)
if err != nil {
t.Errorf("torrent %d: %v", id, err)
continue
}
checked++
if tf.Info.Name == "" {
t.Errorf("torrent %d: empty name", id)
}
if len(tf.Info.Files) == 0 {
t.Errorf("torrent %d (%s): no files", id, tf.Info.Name)
}
// pieces is a concatenation of 20-byte SHA-1 hashes; a length that is
// not a multiple of 20 means the byte-string handling is wrong.
if len(tf.Info.Pieces)%20 != 0 {
t.Errorf("torrent %d: pieces length %d is not a multiple of 20",
id, len(tf.Info.Pieces))
}
var topLevel []string
for _, f := range tf.Info.Files {
if len(f.Path) == 1 {
topLevel = append(topLevel, f.Path[0])
}
}
if findCoverArtInDirectory(topLevel) != "" {
withCover++
}
if len(findAudioFiles(tf.Info.Files)) > 0 {
withAudio++
}
}
if err := rows.Err(); err != nil {
t.Fatal(err)
}
if checked == 0 {
t.Skip("no torrent files in the development database")
}
t.Logf("decoded %d real torrent files: %d with cover art, %d with audio",
checked, withCover, withAudio)
// Every torrent here came from a music tracker, so a torrent with no audio
// file would mean findAudioFiles is missing an extension.
if withAudio != checked {
t.Errorf("%d of %d torrents had no recognised audio file", checked-withAudio, checked)
}
}
|