// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package bzip2
import (
"bytes"
"encoding/hex"
"fmt"
"io"
"io/ioutil"
"testing"
)
func mustDecodeHex(s string) []byte {
b, err := hex.DecodeString(s)
if err != nil {
panic(err)
}
return b
}
func mustLoadFile(f string) []byte {
b, err := ioutil.ReadFile(f)
if err != nil {
panic(err)
}
return b
}
func trim(b []byte) string {
const limit = 1024
if len(b) < limit {
return fmt.Sprintf("%q", b)
}
return fmt.Sprintf("%q...", b[:limit])
}
func TestReader(t *testing.T) {
var vectors = []struct {
desc string
input []byte
output []byte
fail bool
}{{
desc: "hello world",
input: mustDecodeHex("" +
"425a68393141592653594eece83600000251800010400006449080200031064c" +
"4101a7a9a580bb9431f8bb9229c28482776741b0",
),
output: []byte("hello world\n"),
}, {
desc: "concatenated files",
input: mustDecodeHex("" +
"425a68393141592653594eece83600000251800010400006449080200031064c" +
"4101a7a9a580bb9431f8bb9229c28482776741b0425a68393141592653594eec" +
"e83600000251800010400006449080200031064c4101a7a9a580bb9431f8bb92" +
"29c28482776741b0",
),
output: []byte("hello world\nhello world\n"),
}, {
desc: "32B zeros",
input: mustDecodeHex("" +
"425a6839314159265359b5aa5098000000600040000004200021008283177245" +
"385090b5aa5098",
),
output: make([]byte, 32),
}, {
desc: "1MiB zeros",
input: mustDecodeHex("" +
"425a683931415926535938571ce50008084000c0040008200030cc0529a60806" +
"c4201e2ee48a70a12070ae39ca",
),
output: make([]byte, 1<<20),
}, {
desc: "random data",
input: mustLoadFile("testdata/pass-random1.bz2"),
output: mustLoadFile("testdata/pass-random1.bin"),
}, {
desc: "random data - full symbol range",
input: mustLoadFile("testdata/pass-random2.bz2"),
output: mustLoadFile("testdata/pass-random2.bin"),
}, {
desc: "random data - uses RLE1 stage",
input: mustDecodeHex("" +
"425a6839314159265359d992d0f60000137dfe84020310091c1e280e100e0428" +
"01099210094806c0110002e70806402000546034000034000000f28300000320" +
"00d3403264049270eb7a9280d308ca06ad28f6981bee1bf8160727c7364510d7" +
"3a1e123083421b63f031f63993a0f40051fbf177245385090d992d0f60",
),
output: mustDecodeHex("" +
"92d5652616ac444a4a04af1a8a3964aca0450d43d6cf233bd03233f4ba92f871" +
"9e6c2a2bd4f5f88db07ecd0da3a33b263483db9b2c158786ad6363be35d17335" +
"ba",
),
}, {
desc: "1MiB sawtooth",
input: mustLoadFile("testdata/pass-sawtooth.bz2"),
output: func() []byte {
b := make([]byte, 1<<20)
for i := range b {
b[i] = byte(i)
}
return b
}(),
}, {
desc: "RLE2 buffer overrun - issue 5747",
input: mustLoadFile("testdata/fail-issue5747.bz2"),
fail: true,
}, {
desc: "out-of-range selector - issue 8363",
input: mustDecodeHex("" +
"425a68393141592653594eece83600000251800010400006449080200031064c" +
"4101a7a9a580bb943117724538509000000000",
),
fail: true,
}, {
desc: "bad block size - issue 13941",
input: mustDecodeHex("" +
"425a683131415926535936dc55330063ffc0006000200020a40830008b0008b8" +
"bb9229c28481b6e2a998",
),
fail: true,
}, {
desc: "bad huffman delta",
input: mustDecodeHex("" +
"425a6836314159265359b1f7404b000000400040002000217d184682ee48a70a" +
"12163ee80960",
),
fail: true,
}}
for i, v := range vectors {
rd := NewReader(bytes.NewReader(v.input))
buf, err := ioutil.ReadAll(rd)
if fail := bool(err != nil); fail != v.fail {
if fail {
t.Errorf("test %d (%s), unexpected failure: %v", i, v.desc, err)
} else {
t.Errorf("test %d (%s), unexpected success", i, v.desc)
}
}
if !v.fail && !bytes.Equal(buf, v.output) {
t.Errorf("test %d (%s), output mismatch:\ngot %s\nwant %s", i, v.desc, trim(buf), trim(v.output))
}
}
}
func TestBitReader(t *testing.T) {
var vectors = []struct {
nbits uint // Number of bits to read
value int // Expected output value (0 for error)
fail bool // Expected operation failure?
}{
{nbits: 1, value: 1},
{nbits: 1, value: 0},
{nbits: 1, value: 1},
{nbits: 5, value: 11},
{nbits: 32, value: 0x12345678},
{nbits: 15, value: 14495},
{nbits: 3, value: 6},
{nbits: 6, value: 13},
{nbits: 1, fail: true},
}
rd := bytes.NewReader([]byte{0xab, 0x12, 0x34, 0x56, 0x78, 0x71, 0x3f, 0x8d})
br := newBitReader(rd)
for i, v := range vectors {
val := br.ReadBits(v.nbits)
if fail := bool(br.err != nil); fail != v.fail {
if fail {
t.Errorf("test %d, unexpected failure: ReadBits(%d) = %v", i, v.nbits, br.err)
} else {
t.Errorf("test %d, unexpected success: ReadBits(%d) = nil", i, v.nbits)
}
}
if !v.fail && val != v.value {
t.Errorf("test %d, mismatching value: ReadBits(%d) = %d, want %d", i, v.nbits, val, v.value)
}
}
}
func TestMTF(t *testing.T) {
var vectors = []struct {
idx int // Input index
sym uint8 // Expected output symbol
}{
{idx: 1, sym: 1}, // [1 0 2 3 4]
{idx: 0, sym: 1}, // [1 0 2 3 4]
{idx: 1, sym: 0}, // [0 1 2 3 4]
{idx: 4, sym: 4}, // [4 0 1 2 3]
{idx: 1, sym: 0}, // [0 4 1 2 3]
}
mtf := newMTFDecoderWithRange(5)
for i, v := range vectors {
sym := mtf.Decode(v.idx)
t.Log(mtf)
if sym != v.sym {
t.Errorf("test %d, symbol mismatch: Decode(%d) = %d, want %d", i, v.idx, sym, v.sym)
}
}
}
func TestZeroRead(t *testing.T) {
b := mustDecodeHex("425a6839314159265359b5aa5098000000600040000004200021008283177245385090b5aa5098")
r := NewReader(bytes.NewReader(b))
if n, err := r.Read(nil); n != 0 || err != nil {
t.Errorf("Read(nil) = (%d, %v), want (0, nil)", n, err)
}
}
var (
digits = mustLoadFile("testdata/e.txt.bz2")
newton = mustLoadFile("testdata/Isaac.Newton-Opticks.txt.bz2")
random = mustLoadFile("testdata/random.data.bz2")
)
func benchmarkDecode(b *testing.B, compressed []byte) {
// Determine the uncompressed size of testfile.
uncompressedSize, err := io.Copy(ioutil.Discard, NewReader(bytes.NewReader(compressed)))
if err != nil {
b.Fatal(err)
}
b.SetBytes(uncompressedSize)
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
r := bytes.NewReader(compressed)
io.Copy(ioutil.Discard, NewReader(r))
}
}
func BenchmarkDecodeDigits(b *testing.B) { benchmarkDecode(b, digits) }
func BenchmarkDecodeNewton(b *testing.B) { benchmarkDecode(b, newton) }
func BenchmarkDecodeRand(b *testing.B) { benchmarkDecode(b, random) }