summaryrefslogtreecommitdiff
path: root/libgo/go/encoding/binary/varint_test.go
diff options
context:
space:
mode:
Diffstat (limited to 'libgo/go/encoding/binary/varint_test.go')
-rw-r--r--libgo/go/encoding/binary/varint_test.go182
1 files changed, 182 insertions, 0 deletions
diff --git a/libgo/go/encoding/binary/varint_test.go b/libgo/go/encoding/binary/varint_test.go
new file mode 100644
index 00000000000..ef51f09293b
--- /dev/null
+++ b/libgo/go/encoding/binary/varint_test.go
@@ -0,0 +1,182 @@
+// 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 binary
+
+import (
+ "bytes"
+ "os"
+ "testing"
+)
+
+func testConstant(t *testing.T, w uint, max int) {
+ buf := make([]byte, MaxVarintLen64)
+ n := PutUvarint(buf, 1<<w-1)
+ if n != max {
+ t.Errorf("MaxVarintLen%d = %d; want %d", w, max, n)
+ }
+}
+
+func TestConstants(t *testing.T) {
+ testConstant(t, 16, MaxVarintLen16)
+ testConstant(t, 32, MaxVarintLen32)
+ testConstant(t, 64, MaxVarintLen64)
+}
+
+func testVarint(t *testing.T, x int64) {
+ buf1 := make([]byte, MaxVarintLen64)
+ n := PutVarint(buf1[:], x)
+ y, m := Varint(buf1[0:n])
+ if x != y {
+ t.Errorf("Varint(%d): got %d", x, y)
+ }
+ if n != m {
+ t.Errorf("Varint(%d): got n = %d; want %d", x, m, n)
+ }
+
+ var buf2 bytes.Buffer
+ err := WriteVarint(&buf2, x)
+ if err != nil {
+ t.Errorf("WriteVarint(%d): %s", x, err)
+ }
+ if n != buf2.Len() {
+ t.Errorf("WriteVarint(%d): got n = %d; want %d", x, buf2.Len(), n)
+ }
+ y, err = ReadVarint(&buf2)
+ if err != nil {
+ t.Errorf("ReadVarint(%d): %s", x, err)
+ }
+ if x != y {
+ t.Errorf("ReadVarint(%d): got %d", x, y)
+ }
+}
+
+func testUvarint(t *testing.T, x uint64) {
+ buf1 := make([]byte, MaxVarintLen64)
+ n := PutUvarint(buf1[:], x)
+ y, m := Uvarint(buf1[0:n])
+ if x != y {
+ t.Errorf("Uvarint(%d): got %d", x, y)
+ }
+ if n != m {
+ t.Errorf("Uvarint(%d): got n = %d; want %d", x, m, n)
+ }
+
+ var buf2 bytes.Buffer
+ err := WriteUvarint(&buf2, x)
+ if err != nil {
+ t.Errorf("WriteUvarint(%d): %s", x, err)
+ }
+ if n != buf2.Len() {
+ t.Errorf("WriteUvarint(%d): got n = %d; want %d", x, buf2.Len(), n)
+ }
+ y, err = ReadUvarint(&buf2)
+ if err != nil {
+ t.Errorf("ReadUvarint(%d): %s", x, err)
+ }
+ if x != y {
+ t.Errorf("ReadUvarint(%d): got %d", x, y)
+ }
+}
+
+var tests = []int64{
+ -1 << 63,
+ -1<<63 + 1,
+ -1,
+ 0,
+ 1,
+ 2,
+ 10,
+ 20,
+ 63,
+ 64,
+ 65,
+ 127,
+ 128,
+ 129,
+ 255,
+ 256,
+ 257,
+ 1<<63 - 1,
+}
+
+func TestVarint(t *testing.T) {
+ for _, x := range tests {
+ testVarint(t, x)
+ testVarint(t, -x)
+ }
+ for x := int64(0x7); x != 0; x <<= 1 {
+ testVarint(t, x)
+ testVarint(t, -x)
+ }
+}
+
+func TestUvarint(t *testing.T) {
+ for _, x := range tests {
+ testUvarint(t, uint64(x))
+ }
+ for x := uint64(0x7); x != 0; x <<= 1 {
+ testUvarint(t, x)
+ }
+}
+
+func TestBufferTooSmall(t *testing.T) {
+ buf := []byte{0x80, 0x80, 0x80, 0x80}
+ for i := 0; i <= len(buf); i++ {
+ buf := buf[0:i]
+ x, n := Uvarint(buf)
+ if x != 0 || n != 0 {
+ t.Errorf("Uvarint(%v): got x = %d, n = %d", buf, x, n)
+ }
+
+ x, err := ReadUvarint(bytes.NewBuffer(buf))
+ if x != 0 || err != os.EOF {
+ t.Errorf("ReadUvarint(%v): got x = %d, err = %s", buf, x, err)
+ }
+ }
+}
+
+func testOverflow(t *testing.T, buf []byte, n0 int, err0 os.Error) {
+ x, n := Uvarint(buf)
+ if x != 0 || n != n0 {
+ t.Errorf("Uvarint(%v): got x = %d, n = %d; want 0, %d", buf, x, n, n0)
+ }
+
+ x, err := ReadUvarint(bytes.NewBuffer(buf))
+ if x != 0 || err != err0 {
+ t.Errorf("ReadUvarint(%v): got x = %d, err = %s; want 0, %s", buf, x, err, err0)
+ }
+}
+
+func TestOverflow(t *testing.T) {
+ testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x2}, -10, overflow)
+ testOverflow(t, []byte{0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x1, 0, 0}, -13, overflow)
+}
+
+func TestNonCanonicalZero(t *testing.T) {
+ buf := []byte{0x80, 0x80, 0x80, 0}
+ x, n := Uvarint(buf)
+ if x != 0 || n != 4 {
+ t.Errorf("Uvarint(%v): got x = %d, n = %d; want 0, 4", buf, x, n)
+
+ }
+}
+
+func BenchmarkPutUvarint32(b *testing.B) {
+ buf := make([]byte, MaxVarintLen32)
+ for i := 0; i < b.N; i++ {
+ for j := uint(0); j < MaxVarintLen32; j++ {
+ PutUvarint(buf, 1<<(j*7))
+ }
+ }
+}
+
+func BenchmarkPutUvarint64(b *testing.B) {
+ buf := make([]byte, MaxVarintLen64)
+ for i := 0; i < b.N; i++ {
+ for j := uint(0); j < MaxVarintLen64; j++ {
+ PutUvarint(buf, 1<<(j*7))
+ }
+ }
+}