logdog: Add bundler library.

client/internal/logdog/butler/bundler/sizer_test.go

Index: client/internal/logdog/butler/bundler/sizer_test.go
diff --git a/client/internal/logdog/butler/bundler/sizer_test.go b/client/internal/logdog/butler/bundler/sizer_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..1c8a0f0739881786ac051cd75b16b9367e844d1e
--- /dev/null
+++ b/client/internal/logdog/butler/bundler/sizer_test.go
@@ -0,0 +1,85 @@
+// 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 bundler
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/golang/protobuf/proto"
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+// A proto.Message implementation with test fields.
+type testMessage struct {
+	U64 uint64 `protobuf:"varint,1,opt,name=u64"`
+}
+
+func (t *testMessage) Reset()         {}
+func (t *testMessage) String() string { return "" }
+func (t *testMessage) ProtoMessage()  {}
+
+func TestFastSizerVarintLength(t *testing.T) {
+	Convey(`A test message`, t, func() {
+		for _, threshold := range []uint64{
+			0,
+			0x80,
+			0x4000,
+			0x200000,
+			0x100000000,
+			0x800000000,
+			0x40000000000,
+			0x2000000000000,
+			0x100000000000000,
+			0x8000000000000000,
+		} {
+
+			for _, delta := range []int64{
+				-2,
+				-1,
+				0,
+				1,
+				2,
+			} {
+				// Add "delta" to "threshold" in a uint64-aware manner.
+				u64 := threshold
+				if delta >= 0 {
+					u64 += uint64(delta)
+				} else {
+					if u64 < uint64(-delta) {
+						continue
+					}
+					u64 -= uint64(-delta)
+				}
+
+				expected := varintLength(u64)
+				Convey(fmt.Sprintf(`Testing threshold 0x%x should encode to varint size %d`, u64, expected), func() {
+					m := &testMessage{
+						U64: u64,
+					}
+
+					expectedSize := proto.Size(m)
+					if u64 == 0 {
+						// Proto3 doesn't encode default values (0), so the expected size of
+						// the number zero is zero.
+						expectedSize = 0
+					} else {
+						// Accommodate the tag ("1").
+						expectedSize -= varintLength(1)
+					}
+					So(expected, ShouldEqual, expectedSize)
+				})
+			}
+		}
+	})
+
+	Convey(`Calculates protobuf size.`, t, func() {
+		pbuf := &testMessage{
+			U64: 0x600dd065,
+		}
+
+		So(protoSize(pbuf), ShouldEqual, proto.Size(pbuf))
+	})
+}