Add `chunk` segmented data library.

common/chunkstream/chunk_test.go

Index: common/chunkstream/chunk_test.go
diff --git a/common/chunkstream/chunk_test.go b/common/chunkstream/chunk_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..734177c8bb9fdc6fcc6a342339fcf19a48a5a226
--- /dev/null
+++ b/common/chunkstream/chunk_test.go
@@ -0,0 +1,70 @@
+// Copyright 2015 The Chromium 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 chunkstream
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+type testChunk struct {
+	data     []byte
+	released bool
+}
+
+var _ Chunk = (*testChunk)(nil)
+
+func tc(d ...byte) *testChunk {
+	return &testChunk{
+		data: d,
+	}
+}
+
+func (c *testChunk) String() string {
+	pieces := make([]string, len(c.data))
+	for i, d := range c.data {
+		pieces[i] = fmt.Sprintf("0x%02x", d)
+	}
+	return fmt.Sprintf("{%s}", strings.Join(pieces, ", "))
+}
+
+func (c *testChunk) Bytes() []byte {
+	return c.data
+}
+
+func (c *testChunk) Len() int {
+	return len(c.data)
+}
+
+func (c *testChunk) Release() {
+	if c.released {
+		panic("double-free")
+	}
+	c.released = true
+}
+
+func TestChunkNode(t *testing.T) {
+	Convey(`A chunkNode wrapping a testing Chunk implementation`, t, func() {
+		c := tc(0, 1, 2)
+		n := newChunkNode(c)
+
+		Convey(`Should call Chunk methods.`, func() {
+			So(n.Bytes(), ShouldResemble, []byte{0, 1, 2})
+			So(n.Len(), ShouldEqual, 3)
+		})
+
+		Convey(`When released, releases the wrapped Chunk.`, func() {
+			n.release()
+			So(c.released, ShouldBeTrue)
+
+			Convey(`If released again, panics.`, func() {
+				So(func() { n.release() }, ShouldPanic)
+			})
+		})
+	})
+}