Make Get operations only serialize the bare minimum.

service/datastore/pls_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.
 
 // adapted from github.com/golang/appengine/datastore
 
 package datastore
 
 import (
         "bytes"
@@ skipping 357 matching lines @@
                                 So(props[i].SetValue(v+v, props[i].IndexSetting()), ShouldBeNil)
                         case int64:
                                 // + means integer addition.
                                 So(props[i].SetValue(v+v, props[i].IndexSetting()), ShouldBeNil)
                         }
                 }
         }
         return propMap, nil
 }
 
+func (d *Doubler) GetAllMeta() PropertyMap                               { return nil }
 func (d *Doubler) GetMeta(string) (interface{}, error)                   { return nil, ErrMetaFieldUnset }
 func (d *Doubler) GetMetaDefault(_ string, dflt interface{}) interface{} { return dflt }
 func (d *Doubler) SetMeta(string, interface{}) error                     { return ErrMetaFieldUnset }
 func (d *Doubler) Problem() error                                        { return nil }
 
 var _ PropertyLoadSaver = (*Doubler)(nil)
 
 type Deriver struct {
         S, Derived, Ignored string
 }
 
 func (d *Deriver) Load(props PropertyMap) error {
         for name, p := range props {
                 if name != "S" {
                         continue
                 }
                 d.S = p[0].Value().(string)
                 d.Derived = "derived+" + d.S
         }
         return nil
 }
 
 func (d *Deriver) Save(withMeta bool) (PropertyMap, error) {
         return map[string][]Property{
                 "S": {mp(d.S)},
         }, nil
 }
 
+func (d *Deriver) GetAllMeta() PropertyMap                               { return nil }
 func (d *Deriver) GetMeta(string) (interface{}, error)                   { return nil, ErrMetaFieldUnset }
 func (d *Deriver) GetMetaDefault(_ string, dflt interface{}) interface{} { return dflt }
 func (d *Deriver) SetMeta(string, interface{}) error                     { return ErrMetaFieldUnset }
 func (d *Deriver) Problem() error                                        { return nil }
 
 var _ PropertyLoadSaver = (*Deriver)(nil)
 
 type BK struct {
         Key blobstore.Key
 }
@@ skipping 1295 matching lines @@
 
                 Convey("Bad default meta type", func() {
                         type BadDefault struct {
                                 Val time.Time `gae:"$meta,tomorrow"`
                         }
                         pls := GetPLS(&BadDefault{})
                         So(pls.Problem().Error(), ShouldContainSubstring, "bad type")
                 })
         })
 }