Re-add metadata passthrough on Get operations

service/datastore/raw_interface_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.
+
+package datastore
+
+import (
+        "testing"
+
+        . "github.com/smartystreets/goconvey/convey"
+)
+
+func TestMultiMetaGetter(t *testing.T) {
+        t.Parallel()
+
+        Convey("Test MultiMetaGetter", t, func() {
+                Convey("nil", func() {
+                        mmg := NewMultiMetaGetter(nil)
+                        val, err := mmg.GetMeta(7, "hi")
+                        So(err, ShouldEqual, ErrMetaFieldUnset)
+                        So(val, ShouldBeNil)
+
+                        So(mmg.GetMetaDefault(7, "hi", "value"), ShouldEqual, "value")
+
+                        m := mmg.GetSingle(10)
+                        val, err = m.GetMeta("hi")
+                        So(err, ShouldEqual, ErrMetaFieldUnset)
+                        So(val, ShouldBeNil)
+                        So(m.GetMetaDefault("hi", "value"), ShouldEqual, "value")
+                })
+
+                Convey("stuff", func() {
+                        pmaps := []PropertyMap{{}, nil, {}}
+                        pmaps[0].SetMeta("hi", "thing")
+                        pmaps[2].SetMeta("key", 100)
+                        mmg := NewMultiMetaGetter(pmaps)
+
+                        // oob is OK
+                        So(mmg.GetMetaDefault(7, "hi", "value"), ShouldEqual, "value")
+
+                        // nil is OK
+                        So(mmg.GetMetaDefault(1, "key", true), ShouldEqual, true)
+
+                        val, err := mmg.GetMeta(0, "hi")
+                        So(err, ShouldBeNil)
+                        So(val, ShouldEqual, "thing")
+
+                        So(mmg.GetMetaDefault(2, "key", 20), ShouldEqual, 100)
+                })
+        })
+}