Simple memory testing for gae/wrapper

go/src/infra/gae/libs/wrapper/memory/globalinfo.go

Index: go/src/infra/gae/libs/wrapper/memory/globalinfo.go
diff --git a/go/src/infra/gae/libs/wrapper/memory/globalinfo.go b/go/src/infra/gae/libs/wrapper/memory/globalinfo.go
new file mode 100644
index 0000000000000000000000000000000000000000..951c3c4e69c02aab4c776fb155d49381aad1523c
--- /dev/null
+++ b/go/src/infra/gae/libs/wrapper/memory/globalinfo.go
@@ -0,0 +1,39 @@
+// 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 memory
+
+import (
+	"infra/gae/libs/wrapper"
+
+	"golang.org/x/net/context"
+)
+
+type giContextKeyType int
+
+var giContextKey giContextKeyType
+
+func curGID(c context.Context) *globalInfoData {
+	return c.Value(giContextKey).(*globalInfoData)
+}
+
+// UseGI adds a wrapper.GlobalInfo context, accessible
+// by wrapper.GetGI(c)
+func UseGI(c context.Context) context.Context {
+	return wrapper.SetGIFactory(c, func(ic context.Context) wrapper.GlobalInfo {
+		return &giImpl{wrapper.DummyGI(), curGID(ic), ic}
+	})
+}
+
+type globalInfoData struct{ namespace string }
+
+type giImpl struct {
+	wrapper.GlobalInfo
+	data *globalInfoData
+	c    context.Context
+}
+
+func (gi *giImpl) Namespace(ns string) (context.Context, error) {
+	return context.WithValue(gi.c, giContextKey, &globalInfoData{ns}), nil
+}