integer encode/decode

R=rsc
DELTA=185  (175 added, 10 deleted, 0 changed)
OCL=30863
CL=30871

1 files changed, 98 insertions, 0 deletions

diff --git a/src/pkg/gob/codec_test.go b/src/pkg/gob/codec_test.go
new file mode 100644
index 000000000..8142aac69
--- /dev/null
+++ b/src/pkg/gob/codec_test.go
@@ -0,0 +1,98 @@
+// 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 gob
+
+import (
+	"bytes";
+	"gob";
+	"io";
+	"os";
+	"testing";
+)
+
+// Guarantee encoding format by comparing some encodings to hand-written values
+type EncodeT struct {
+	x	uint64;
+	b	[]byte;
+}
+var encodeT = []EncodeT {
+	EncodeT{ 0x00,	[]byte{0x80} },
+	EncodeT{ 0x0f,	[]byte{0x8f} },
+	EncodeT{ 0xff,	[]byte{0x7f, 0x81} },
+	EncodeT{ 0xffff,	[]byte{0x7f, 0x7f, 0x83} },
+	EncodeT{ 0xffffff,	[]byte{0x7f, 0x7f, 0x7f, 0x87} },
+	EncodeT{ 0xffffffff,	[]byte{0x7f, 0x7f, 0x7f, 0x7f, 0x8f} },
+	EncodeT{ 0xffffffffff,	[]byte{0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x9f} },
+	EncodeT{ 0xffffffffffff,	[]byte{0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0xbf} },
+	EncodeT{ 0xffffffffffffff,	[]byte{0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0xff} },
+	EncodeT{ 0xffffffffffffffff,	[]byte{0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x81} },
+	EncodeT{ 0x1111,	[]byte{0x11, 0xa2} },
+	EncodeT{ 0x1111111111111111,	[]byte{0x11, 0x22, 0x44, 0x08, 0x11, 0x22, 0x44, 0x08, 0x91} },
+	EncodeT{ 0x8888888888888888,	[]byte{0x08, 0x11, 0x22, 0x44, 0x08, 0x11, 0x22, 0x44, 0x08, 0x81} },
+	EncodeT{ 1<<63,	[]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x81} },
+}
+
+// Test basic encode/decode routines for unsigned integers
+func TestUintCodec(t *testing.T) {
+	var b = new(io.ByteBuffer);
+	for i, tt := range encodeT {
+		b.Reset();
+		err := EncodeUint(b, tt.x);
+		if err != nil {
+			t.Error("EncodeUint:", tt.x, err)
+		}
+		if !bytes.Equal(tt.b, b.Data()) {
+			t.Errorf("EncodeUint: expected % x got % x", tt.b, b.Data())
+		}
+	}
+	for u := uint64(0); ; u = (u+1) * 7 {
+		b.Reset();
+		err := EncodeUint(b, u);
+		if err != nil {
+			t.Error("EncodeUint:", u, err)
+		}
+		v, err := DecodeUint(b);
+		if err != nil {
+			t.Error("DecodeUint:", u, err)
+		}
+		if u != v {
+			t.Errorf("Encode/Decode: sent %#x received %#x\n", u, v)
+		}
+		if u & (1<<63) != 0 {
+			break
+		}
+	}
+}
+
+func verifyInt(i int64, t *testing.T) {
+	var b = new(io.ByteBuffer);
+	err := EncodeInt(b, i);
+	if err != nil {
+		t.Error("EncodeInt:", i, err)
+	}
+	j, err := DecodeInt(b);
+	if err != nil {
+		t.Error("DecodeInt:", i, err)
+	}
+	if i != j {
+		t.Errorf("Encode/Decode: sent %#x received %#x\n", uint64(i), uint64(j))
+	}
+}
+
+// Test basic encode/decode routines for signed integers
+func TestIntCodec(t *testing.T) {
+	var b = new(io.ByteBuffer);
+	for u := uint64(0); ; u = (u+1) * 7 {
+		// Do positive and negative values
+		i := int64(u);
+		verifyInt(i, t);
+		verifyInt(-i, t);
+		verifyInt(^i, t);
+		if u & (1<<63) != 0 {
+			break
+		}
+	}
+	verifyInt(-1<<63, t);	// a tricky case
+}