diff options
Diffstat (limited to 'src/compress/flate/deflate_test.go')
| -rw-r--r-- | src/compress/flate/deflate_test.go | 490 |
1 files changed, 490 insertions, 0 deletions
diff --git a/src/compress/flate/deflate_test.go b/src/compress/flate/deflate_test.go new file mode 100644 index 000000000..730234c38 --- /dev/null +++ b/src/compress/flate/deflate_test.go @@ -0,0 +1,490 @@ +// Copyright 2009 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 flate + +import ( + "bytes" + "fmt" + "io" + "io/ioutil" + "reflect" + "sync" + "testing" +) + +type deflateTest struct { + in []byte + level int + out []byte +} + +type deflateInflateTest struct { + in []byte +} + +type reverseBitsTest struct { + in uint16 + bitCount uint8 + out uint16 +} + +var deflateTests = []*deflateTest{ + {[]byte{}, 0, []byte{1, 0, 0, 255, 255}}, + {[]byte{0x11}, -1, []byte{18, 4, 4, 0, 0, 255, 255}}, + {[]byte{0x11}, DefaultCompression, []byte{18, 4, 4, 0, 0, 255, 255}}, + {[]byte{0x11}, 4, []byte{18, 4, 4, 0, 0, 255, 255}}, + + {[]byte{0x11}, 0, []byte{0, 1, 0, 254, 255, 17, 1, 0, 0, 255, 255}}, + {[]byte{0x11, 0x12}, 0, []byte{0, 2, 0, 253, 255, 17, 18, 1, 0, 0, 255, 255}}, + {[]byte{0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}, 0, + []byte{0, 8, 0, 247, 255, 17, 17, 17, 17, 17, 17, 17, 17, 1, 0, 0, 255, 255}, + }, + {[]byte{}, 1, []byte{1, 0, 0, 255, 255}}, + {[]byte{0x11}, 1, []byte{18, 4, 4, 0, 0, 255, 255}}, + {[]byte{0x11, 0x12}, 1, []byte{18, 20, 2, 4, 0, 0, 255, 255}}, + {[]byte{0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}, 1, []byte{18, 132, 2, 64, 0, 0, 0, 255, 255}}, + {[]byte{}, 9, []byte{1, 0, 0, 255, 255}}, + {[]byte{0x11}, 9, []byte{18, 4, 4, 0, 0, 255, 255}}, + {[]byte{0x11, 0x12}, 9, []byte{18, 20, 2, 4, 0, 0, 255, 255}}, + {[]byte{0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}, 9, []byte{18, 132, 2, 64, 0, 0, 0, 255, 255}}, +} + +var deflateInflateTests = []*deflateInflateTest{ + {[]byte{}}, + {[]byte{0x11}}, + {[]byte{0x11, 0x12}}, + {[]byte{0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}}, + {[]byte{0x11, 0x10, 0x13, 0x41, 0x21, 0x21, 0x41, 0x13, 0x87, 0x78, 0x13}}, + {largeDataChunk()}, +} + +var reverseBitsTests = []*reverseBitsTest{ + {1, 1, 1}, + {1, 2, 2}, + {1, 3, 4}, + {1, 4, 8}, + {1, 5, 16}, + {17, 5, 17}, + {257, 9, 257}, + {29, 5, 23}, +} + +func largeDataChunk() []byte { + result := make([]byte, 100000) + for i := range result { + result[i] = byte(i * i & 0xFF) + } + return result +} + +func TestDeflate(t *testing.T) { + for _, h := range deflateTests { + var buf bytes.Buffer + w, err := NewWriter(&buf, h.level) + if err != nil { + t.Errorf("NewWriter: %v", err) + continue + } + w.Write(h.in) + w.Close() + if !bytes.Equal(buf.Bytes(), h.out) { + t.Errorf("Deflate(%d, %x) = %x, want %x", h.level, h.in, buf.Bytes(), h.out) + } + } +} + +// A sparseReader returns a stream consisting of 0s followed by 1<<16 1s. +// This tests missing hash references in a very large input. +type sparseReader struct { + l int64 + cur int64 +} + +func (r *sparseReader) Read(b []byte) (n int, err error) { + if r.cur >= r.l { + return 0, io.EOF + } + n = len(b) + cur := r.cur + int64(n) + if cur > r.l { + n -= int(cur - r.l) + cur = r.l + } + for i := range b[0:n] { + if r.cur+int64(i) >= r.l-1<<16 { + b[i] = 1 + } else { + b[i] = 0 + } + } + r.cur = cur + return +} + +func TestVeryLongSparseChunk(t *testing.T) { + if testing.Short() { + t.Skip("skipping sparse chunk during short test") + } + w, err := NewWriter(ioutil.Discard, 1) + if err != nil { + t.Errorf("NewWriter: %v", err) + return + } + if _, err = io.Copy(w, &sparseReader{l: 23E8}); err != nil { + t.Errorf("Compress failed: %v", err) + return + } +} + +type syncBuffer struct { + buf bytes.Buffer + mu sync.RWMutex + closed bool + ready chan bool +} + +func newSyncBuffer() *syncBuffer { + return &syncBuffer{ready: make(chan bool, 1)} +} + +func (b *syncBuffer) Read(p []byte) (n int, err error) { + for { + b.mu.RLock() + n, err = b.buf.Read(p) + b.mu.RUnlock() + if n > 0 || b.closed { + return + } + <-b.ready + } +} + +func (b *syncBuffer) signal() { + select { + case b.ready <- true: + default: + } +} + +func (b *syncBuffer) Write(p []byte) (n int, err error) { + n, err = b.buf.Write(p) + b.signal() + return +} + +func (b *syncBuffer) WriteMode() { + b.mu.Lock() +} + +func (b *syncBuffer) ReadMode() { + b.mu.Unlock() + b.signal() +} + +func (b *syncBuffer) Close() error { + b.closed = true + b.signal() + return nil +} + +func testSync(t *testing.T, level int, input []byte, name string) { + if len(input) == 0 { + return + } + + t.Logf("--testSync %d, %d, %s", level, len(input), name) + buf := newSyncBuffer() + buf1 := new(bytes.Buffer) + buf.WriteMode() + w, err := NewWriter(io.MultiWriter(buf, buf1), level) + if err != nil { + t.Errorf("NewWriter: %v", err) + return + } + r := NewReader(buf) + + // Write half the input and read back. + for i := 0; i < 2; i++ { + var lo, hi int + if i == 0 { + lo, hi = 0, (len(input)+1)/2 + } else { + lo, hi = (len(input)+1)/2, len(input) + } + t.Logf("#%d: write %d-%d", i, lo, hi) + if _, err := w.Write(input[lo:hi]); err != nil { + t.Errorf("testSync: write: %v", err) + return + } + if i == 0 { + if err := w.Flush(); err != nil { + t.Errorf("testSync: flush: %v", err) + return + } + } else { + if err := w.Close(); err != nil { + t.Errorf("testSync: close: %v", err) + } + } + buf.ReadMode() + out := make([]byte, hi-lo+1) + m, err := io.ReadAtLeast(r, out, hi-lo) + t.Logf("#%d: read %d", i, m) + if m != hi-lo || err != nil { + t.Errorf("testSync/%d (%d, %d, %s): read %d: %d, %v (%d left)", i, level, len(input), name, hi-lo, m, err, buf.buf.Len()) + return + } + if !bytes.Equal(input[lo:hi], out[:hi-lo]) { + t.Errorf("testSync/%d: read wrong bytes: %x vs %x", i, input[lo:hi], out[:hi-lo]) + return + } + // This test originally checked that after reading + // the first half of the input, there was nothing left + // in the read buffer (buf.buf.Len() != 0) but that is + // not necessarily the case: the write Flush may emit + // some extra framing bits that are not necessary + // to process to obtain the first half of the uncompressed + // data. The test ran correctly most of the time, because + // the background goroutine had usually read even + // those extra bits by now, but it's not a useful thing to + // check. + buf.WriteMode() + } + buf.ReadMode() + out := make([]byte, 10) + if n, err := r.Read(out); n > 0 || err != io.EOF { + t.Errorf("testSync (%d, %d, %s): final Read: %d, %v (hex: %x)", level, len(input), name, n, err, out[0:n]) + } + if buf.buf.Len() != 0 { + t.Errorf("testSync (%d, %d, %s): extra data at end", level, len(input), name) + } + r.Close() + + // stream should work for ordinary reader too + r = NewReader(buf1) + out, err = ioutil.ReadAll(r) + if err != nil { + t.Errorf("testSync: read: %s", err) + return + } + r.Close() + if !bytes.Equal(input, out) { + t.Errorf("testSync: decompress(compress(data)) != data: level=%d input=%s", level, name) + } +} + +func testToFromWithLevelAndLimit(t *testing.T, level int, input []byte, name string, limit int) { + var buffer bytes.Buffer + w, err := NewWriter(&buffer, level) + if err != nil { + t.Errorf("NewWriter: %v", err) + return + } + w.Write(input) + w.Close() + if limit > 0 && buffer.Len() > limit { + t.Errorf("level: %d, len(compress(data)) = %d > limit = %d", level, buffer.Len(), limit) + return + } + r := NewReader(&buffer) + out, err := ioutil.ReadAll(r) + if err != nil { + t.Errorf("read: %s", err) + return + } + r.Close() + if !bytes.Equal(input, out) { + t.Errorf("decompress(compress(data)) != data: level=%d input=%s", level, name) + return + } + testSync(t, level, input, name) +} + +func testToFromWithLimit(t *testing.T, input []byte, name string, limit [10]int) { + for i := 0; i < 10; i++ { + testToFromWithLevelAndLimit(t, i, input, name, limit[i]) + } +} + +func TestDeflateInflate(t *testing.T) { + for i, h := range deflateInflateTests { + testToFromWithLimit(t, h.in, fmt.Sprintf("#%d", i), [10]int{}) + } +} + +func TestReverseBits(t *testing.T) { + for _, h := range reverseBitsTests { + if v := reverseBits(h.in, h.bitCount); v != h.out { + t.Errorf("reverseBits(%v,%v) = %v, want %v", + h.in, h.bitCount, v, h.out) + } + } +} + +type deflateInflateStringTest struct { + filename string + label string + limit [10]int +} + +var deflateInflateStringTests = []deflateInflateStringTest{ + { + "../testdata/e.txt", + "2.718281828...", + [...]int{100018, 50650, 50960, 51150, 50930, 50790, 50790, 50790, 50790, 50790}, + }, + { + "../testdata/Mark.Twain-Tom.Sawyer.txt", + "Mark.Twain-Tom.Sawyer", + [...]int{407330, 187598, 180361, 172974, 169160, 163476, 160936, 160506, 160295, 160295}, + }, +} + +func TestDeflateInflateString(t *testing.T) { + for _, test := range deflateInflateStringTests { + gold, err := ioutil.ReadFile(test.filename) + if err != nil { + t.Error(err) + } + testToFromWithLimit(t, gold, test.label, test.limit) + if testing.Short() { + break + } + } +} + +func TestReaderDict(t *testing.T) { + const ( + dict = "hello world" + text = "hello again world" + ) + var b bytes.Buffer + w, err := NewWriter(&b, 5) + if err != nil { + t.Fatalf("NewWriter: %v", err) + } + w.Write([]byte(dict)) + w.Flush() + b.Reset() + w.Write([]byte(text)) + w.Close() + + r := NewReaderDict(&b, []byte(dict)) + data, err := ioutil.ReadAll(r) + if err != nil { + t.Fatal(err) + } + if string(data) != "hello again world" { + t.Fatalf("read returned %q want %q", string(data), text) + } +} + +func TestWriterDict(t *testing.T) { + const ( + dict = "hello world" + text = "hello again world" + ) + var b bytes.Buffer + w, err := NewWriter(&b, 5) + if err != nil { + t.Fatalf("NewWriter: %v", err) + } + w.Write([]byte(dict)) + w.Flush() + b.Reset() + w.Write([]byte(text)) + w.Close() + + var b1 bytes.Buffer + w, _ = NewWriterDict(&b1, 5, []byte(dict)) + w.Write([]byte(text)) + w.Close() + + if !bytes.Equal(b1.Bytes(), b.Bytes()) { + t.Fatalf("writer wrote %q want %q", b1.Bytes(), b.Bytes()) + } +} + +// See http://code.google.com/p/go/issues/detail?id=2508 +func TestRegression2508(t *testing.T) { + if testing.Short() { + t.Logf("test disabled with -short") + return + } + w, err := NewWriter(ioutil.Discard, 1) + if err != nil { + t.Fatalf("NewWriter: %v", err) + } + buf := make([]byte, 1024) + for i := 0; i < 131072; i++ { + if _, err := w.Write(buf); err != nil { + t.Fatalf("writer failed: %v", err) + } + } + w.Close() +} + +func TestWriterReset(t *testing.T) { + for level := 0; level <= 9; level++ { + if testing.Short() && level > 1 { + break + } + w, err := NewWriter(ioutil.Discard, level) + if err != nil { + t.Fatalf("NewWriter: %v", err) + } + buf := []byte("hello world") + for i := 0; i < 1024; i++ { + w.Write(buf) + } + w.Reset(ioutil.Discard) + + wref, err := NewWriter(ioutil.Discard, level) + if err != nil { + t.Fatalf("NewWriter: %v", err) + } + + // DeepEqual doesn't compare functions. + w.d.fill, wref.d.fill = nil, nil + w.d.step, wref.d.step = nil, nil + if !reflect.DeepEqual(w, wref) { + t.Errorf("level %d Writer not reset after Reset", level) + } + } + testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriter(w, NoCompression) }) + testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriter(w, DefaultCompression) }) + testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriter(w, BestCompression) }) + dict := []byte("we are the world") + testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriterDict(w, NoCompression, dict) }) + testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriterDict(w, DefaultCompression, dict) }) + testResetOutput(t, func(w io.Writer) (*Writer, error) { return NewWriterDict(w, BestCompression, dict) }) +} + +func testResetOutput(t *testing.T, newWriter func(w io.Writer) (*Writer, error)) { + buf := new(bytes.Buffer) + w, err := newWriter(buf) + if err != nil { + t.Fatalf("NewWriter: %v", err) + } + b := []byte("hello world") + for i := 0; i < 1024; i++ { + w.Write(b) + } + w.Close() + out1 := buf.String() + + buf2 := new(bytes.Buffer) + w.Reset(buf2) + for i := 0; i < 1024; i++ { + w.Write(b) + } + w.Close() + out2 := buf2.String() + + if out1 != out2 { + t.Errorf("got %q, expected %q", out2, out1) + } + t.Logf("got %d bytes", len(out1)) +} |