Make setting a Memcache Item with a nil Value OK

impl/prod/everything_test.go

 // 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.
 
 // +build appengine
 
 package prod
 
 import (
         "testing"
         "time"
 
         "github.com/luci/gae/service/blobstore"
         "github.com/luci/gae/service/datastore"
         "github.com/luci/gae/service/info"
+        "github.com/luci/gae/service/memcache"
         "github.com/luci/luci-go/common/logging"
         . "github.com/smartystreets/goconvey/convey"
         "golang.org/x/net/context"
         "google.golang.org/appengine/aetest"
 )
 
 var (
         mp   = datastore.MkProperty
         mpNI = datastore.MkPropertyNI
 )
@@ skipping 19 matching lines @@
                         StronglyConsistentDatastore: true,
                 })
                 So(err, ShouldBeNil)
                 defer inst.Close()
 
                 req, err := inst.NewRequest("GET", "/", nil)
                 So(err, ShouldBeNil)
 
                 ctx := Use(context.Background(), req)
                 ds := datastore.Get(ctx)
+                mc := memcache.Get(ctx)
                 inf := info.Get(ctx)
 
                 // You have to visually confirm that this actually happens in the stdout
                 // of the test... yeah I know.
                 logging.Infof(ctx, "I am a banana")
 
                 Convey("Can probe/change Namespace", func() {
                         So(inf.GetNamespace(), ShouldEqual, "")
                         ctx, err = inf.Namespace("wat")
                         So(err, ShouldBeNil)
@@ skipping 142 matching lines @@
                         tval, err = all[1]["Time"][0].Project(datastore.PTTime)
                         So(err, ShouldBeNil)
                         So(tval, ShouldResemble, pm["Time"][0].Value())
 
                         ent := datastore.PropertyMap{
                                 "$key": {mpNI(ds.MakeKey("Something", "value"))},
                         }
                         So(ds.Get(&ent), ShouldBeNil)
                         So(ent["Time"], ShouldResemble, pm["Time"])
                 })
+
+                Convey("memcache: Set (nil) is the same as Set ([]byte{})", func() {
+                        So(mc.Set(mc.NewItem("bob")), ShouldBeNil) // normally would panic because Value is nil
+
+                        bob, err := mc.Get("bob")
+                        So(err, ShouldBeNil)
+                        So(bob.Value(), ShouldResemble, []byte{})
+                })
         })
 }