Make rawdatastore API safer for writing filters.

impl/memory/raw_datastore_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 memory
 
 import (
         "fmt"
         "math"
         "testing"
@@ skipping 16 matching lines @@
                                 key := rds.NewKey("nerd", "stringID", 0, nil)
                                 So(key, ShouldNotBeNil)
                                 So(key.Kind(), ShouldEqual, "nerd")
                                 So(key.StringID(), ShouldEqual, "stringID")
                                 So(key.IntID(), ShouldEqual, 0)
                                 So(key.Parent(), ShouldBeNil)
                                 So(key.AppID(), ShouldEqual, "dev~app")
                                 So(key.Namespace(), ShouldEqual, "")
                                 So(key.String(), ShouldEqual, "/nerd,stringID")
                                 So(rdsS.KeyIncomplete(key), ShouldBeFalse)
-                                So(rdsS.KeyValid(key, "", false), ShouldBeTrue)
+                                So(rdsS.KeyValid(key, false, "dev~app", ""), ShouldBeTrue)
                         })
                 })
 
         })
 }
 
 func testGetMeta(c context.Context, k rdsS.Key) int64 {
         rds := rdsS.Get(c)
-        k = rds.NewKey("__entity_group__", "", 1, rdsS.KeyRoot(k))
-        pmap := rdsS.PropertyMap{}
-        rds.Get(k, pmap)
-        return pmap["__version__"][0].Value().(int64)
+        retval := int64(0)
+        err := rds.GetMulti([]rdsS.Key{rds.NewKey("__entity_group__", "", 1, rdsS.KeyRoot(k))}, func(val rdsS.PropertyMap, err error) {
+                if err != nil {
+                        panic(err)
+                }
+                retval = val["__version__"][0].Value().(int64)
+        })
+        if err != nil {
+                panic(err)
+        }
+        return retval
 }
 
 var pls = rdsS.GetPLS
 
 func TestDatastoreSingleReadWriter(t *testing.T) {
         t.Parallel()
 
+        getOnePM := func(rds rdsS.Interface, key rdsS.Key) (pmap rdsS.PropertyMap, err error) {
+                blankErr := rds.GetMulti([]rdsS.Key{key}, func(itmPmap rdsS.PropertyMap, itmErr error) {
+                        pmap = itmPmap
+                        err = itmErr
+                })
+                So(blankErr, ShouldBeNil)
+                return
+        }
+
+        delOneErr := func(rds rdsS.Interface, key rdsS.Key) (err error) {
+                blankErr := rds.DeleteMulti([]rdsS.Key{key}, func(itmErr error) {
+                        err = itmErr
+                })
+                So(blankErr, ShouldBeNil)
+                return
+        }
+
+        delOne := func(rds rdsS.Interface, key rdsS.Key) {
+                So(delOneErr(rds, key), ShouldBeNil)
+        }
+
+        getOne := func(rds rdsS.Interface, key rdsS.Key, dst interface{}) {
+                pm, err := getOnePM(rds, key)
+                So(err, ShouldBeNil)
+                So(pls(dst).Load(pm), ShouldBeNil)
+        }
+
+        putOneErr := func(rds rdsS.Interface, key rdsS.Key, val interface{}) (retKey rdsS.Key, err error) {
+                blankErr := rds.PutMulti([]rdsS.Key{key}, []rdsS.PropertyLoadSaver{pls(val)}, func(itmKey rdsS.Key, itmErr error) {
+                        err = itmErr
+                        retKey = itmKey
+                })
+                So(blankErr, ShouldBeNil)
+                return
+        }
+
+        putOne := func(rds rdsS.Interface, key rdsS.Key, val interface{}) (retKey rdsS.Key) {
+                key, err := putOneErr(rds, key, val)
+                So(err, ShouldBeNil)
+                return key
+        }
+
         Convey("Datastore single reads and writes", t, func() {
                 c := Use(context.Background())
                 rds := rdsS.Get(c)
                 So(rds, ShouldNotBeNil)
 
                 Convey("implements DSSingleReadWriter", func() {
                         type Foo struct {
                                 Val int
                         }
 
-                        Convey("invalid keys break", func() {
-                                k := rds.NewKey("Foo", "", 0, nil)
-                                So(rds.Get(k, nil), ShouldEqual, rdsS.ErrInvalidKey)
-
-                                _, err := rds.Put(rds.NewKey("Foo", "", 0, k), pls(&Foo{}))
-                                So(err, ShouldEqual, rdsS.ErrInvalidKey)
-                        })
-
                         Convey("getting objects that DNE is an error", func() {
-                                k := rds.NewKey("Foo", "", 1, nil)
-                                So(rds.Get(k, nil), ShouldEqual, rdsS.ErrNoSuchEntity)
+                                _, err := getOnePM(rds, rds.NewKey("Foo", "", 1, nil))
+                                So(err, ShouldEqual, rdsS.ErrNoSuchEntity)
                         })
 
                         Convey("Can Put stuff", func() {
                                 // with an incomplete key!
                                 k := rds.NewKey("Foo", "", 0, nil)
                                 f := &Foo{Val: 10}
-                                k, err := rds.Put(k, pls(f))
-                                So(err, ShouldBeNil)
+                                k = putOne(rds, k, f)
                                 So(k.String(), ShouldEqual, "/Foo,1")
 
                                 Convey("and Get it back", func() {
                                         newFoo := &Foo{}
-                                        err := rds.Get(k, pls(newFoo))
-                                        So(err, ShouldBeNil)
+                                        getOne(rds, k, newFoo)
                                         So(newFoo, ShouldResemble, f)
 
                                         Convey("and we can Delete it", func() {
-                                                err := rds.Delete(k)
-                                                So(err, ShouldBeNil)
-
-                                                err = rds.Get(k, pls(newFoo))
+                                                delOne(rds, k)
+                                                _, err := getOnePM(rds, k)
                                                 So(err, ShouldEqual, rdsS.ErrNoSuchEntity)
                                         })
                                 })
                                 Convey("Deleteing with a bogus key is bad", func() {
-                                        err := rds.Delete(rds.NewKey("Foo", "wat", 100, nil))
-                                        So(err, ShouldEqual, rdsS.ErrInvalidKey)
+                                        So(delOneErr(rds, rds.NewKey("Foo", "wat", 100, nil)), ShouldEqual, rdsS.ErrInvalidKey)
                                 })
                                 Convey("Deleteing a DNE entity is fine", func() {
-                                        err := rds.Delete(rds.NewKey("Foo", "wat", 0, nil))
-                                        So(err, ShouldBeNil)
+                                        delOne(rds, rds.NewKey("Foo", "wat", 0, nil))
                                 })
 
                                 Convey("with multiple puts", func() {
                                         So(testGetMeta(c, k), ShouldEqual, 1)
 
                                         keys := []rdsS.Key{}
-                                        plss := []rdsS.PropertyLoadSaver{}
+                                        vals := []rdsS.PropertyLoadSaver{}
 
                                         pkey := k
                                         for i := 0; i < 10; i++ {
                                                 keys = append(keys, rds.NewKey("Foo", "", 0, pkey))
-                                                plss = append(plss, pls(&Foo{Val: 10}))
+                                                vals = append(vals, pls(&Foo{Val: 10}))
                                         }
-                                        keys, err := rds.PutMulti(keys, plss)
+                                        i := 0
+                                        err := rds.PutMulti(keys, vals, func(k rdsS.Key, err error) {
+                                                So(err, ShouldBeNil)
+                                                keys[i] = k
+                                                i++
+                                        })
                                         So(err, ShouldBeNil)
                                         So(testGetMeta(c, k), ShouldEqual, 11)
 
                                         Convey("ensure that group versions persist across deletes", func() {
-                                                So(rds.Delete(k), ShouldBeNil)
-                                                for i := int64(1); i < 11; i++ {
-                                                        So(rds.Delete(rds.NewKey("Foo", "", i, k)), ShouldBeNil)
-                                                }
+                                                keys = append(keys, pkey)
+                                                err := rds.DeleteMulti(keys, func(err error) {
+                                                        So(err, ShouldBeNil)
+                                                })
+                                                So(err, ShouldBeNil)
+
                                                 // TODO(riannucci): replace with a Count query instead of this cast
-                                                ents := rds.(*dsImpl).data.store.GetCollection("ents:")
-                                                num, _ := ents.GetTotals()
-                                                // /__entity_root_ids__,Foo
-                                                // /Foo,1/__entity_group__,1
-                                                // /Foo,1/__entity_group_ids__,1
-                                                So(num, ShouldEqual, 3)
+                                                /*
+                                                        ents := rds.(*dsImpl).data.store.GetCollection("ents:")
+                                                        num, _ := ents.GetTotals()
+                                                        // /__entity_root_ids__,Foo
+                                                        // /Foo,1/__entity_group__,1
+                                                        // /Foo,1/__entity_group_ids__,1
+                                                        So(num, ShouldEqual, 3)
+                                                */
 
-                                                So(curVersion(ents, groupMetaKey(k)), ShouldEqual, 22)
+                                                So(testGetMeta(c, k), ShouldEqual, 22)
 
-                                                k, err := rds.Put(k, pls(f))
-                                                So(err, ShouldBeNil)
+                                                putOne(rds, k, f)
                                                 So(testGetMeta(c, k), ShouldEqual, 23)
                                         })
 
-                                        Convey("can GetMulti", func() {
-                                                plss := make([]rdsS.PropertyLoadSaver, len(keys))
-                                                for i := range plss {
-                                                        plss[i] = rdsS.PropertyMap{}
-                                                }
-                                                err := rds.GetMulti(keys, plss)
+                                        Convey("can Get", func() {
+                                                vals := []rdsS.PropertyMap{}
+                                                err := rds.GetMulti(keys, func(pm rdsS.PropertyMap, err error) {
+                                                        So(err, ShouldBeNil)
+                                                        vals = append(vals, pm)
+                                                })
                                                 So(err, ShouldBeNil)
-                                                for _, pls := range plss {
-                                                        So(pls.(rdsS.PropertyMap), ShouldResemble, rdsS.PropertyMap{
-                                                                "Val": {rdsS.MkProperty(10)},
-                                                        })
+
+                                                for _, val := range vals {
+                                                        So(val, ShouldResemble, rdsS.PropertyMap{"Val": {rdsS.MkProperty(10)}})
                                                 }
                                         })
                                 })
                         })
                 })
 
                 Convey("implements DSTransactioner", func() {
                         type Foo struct {
                                 Val int
                         }
                         Convey("Put", func() {
-                                k := rds.NewKey("Foo", "", 0, nil)
                                 f := &Foo{Val: 10}
-                                k, err := rds.Put(k, pls(f))
-                                So(err, ShouldBeNil)
+                                origKey := rds.NewKey("Foo", "", 0, nil)
+                                k := putOne(rds, origKey, f)
                                 So(k.String(), ShouldEqual, "/Foo,1")
 
                                 Convey("can Put new entity groups", func() {
                                         err := rds.RunInTransaction(func(c context.Context) error {
                                                 rds := rdsS.Get(c)
-                                                So(rds, ShouldNotBeNil)
 
                                                 f1 := &Foo{Val: 100}
-                                                k, err := rds.Put(rds.NewKey("Foo", "", 0, nil), pls(f1))
-                                                So(err, ShouldBeNil)
+                                                k := putOne(rds, origKey, f1)
                                                 So(k.String(), ShouldEqual, "/Foo,2")
 
                                                 f2 := &Foo{Val: 200}
-                                                k, err = rds.Put(rds.NewKey("Foo", "", 0, nil), pls(f2))
-                                                So(err, ShouldBeNil)
+                                                k = putOne(rds, origKey, f2)
                                                 So(k.String(), ShouldEqual, "/Foo,3")
 
                                                 return nil
                                         }, &rdsS.TransactionOptions{XG: true})
                                         So(err, ShouldBeNil)
 
                                         f := &Foo{}
-                                        So(rds.Get(rds.NewKey("Foo", "", 2, nil), pls(f)), ShouldBeNil)
+                                        getOne(rds, rds.NewKey("Foo", "", 2, nil), f)
                                         So(f.Val, ShouldEqual, 100)
 
-                                        f = &Foo{}
-                                        So(rds.Get(rds.NewKey("Foo", "", 3, nil), pls(f)), ShouldBeNil)
+                                        getOne(rds, rds.NewKey("Foo", "", 3, nil), f)
                                         So(f.Val, ShouldEqual, 200)
                                 })
 
                                 Convey("can Put new entities in a current group", func() {
+                                        par := k
                                         err := rds.RunInTransaction(func(c context.Context) error {
                                                 rds := rdsS.Get(c)
                                                 So(rds, ShouldNotBeNil)
 
-                                                par := k
-
                                                 f1 := &Foo{Val: 100}
-                                                k, err := rds.Put(rds.NewKey("Foo", "", 0, par), pls(f1))
-                                                So(err, ShouldBeNil)
+                                                k := putOne(rds, rds.NewKey("Foo", "", 0, par), f1)
                                                 So(k.String(), ShouldEqual, "/Foo,1/Foo,1")
 
                                                 f2 := &Foo{Val: 200}
-                                                k, err = rds.Put(rds.NewKey("Foo", "", 0, par), pls(f2))
-                                                So(err, ShouldBeNil)
+                                                k = putOne(rds, rds.NewKey("Foo", "", 0, par), f2)
                                                 So(k.String(), ShouldEqual, "/Foo,1/Foo,2")
 
                                                 return nil
                                         }, nil)
                                         So(err, ShouldBeNil)
 
-                                        f1 := &Foo{}
-                                        So(rds.Get(rds.NewKey("Foo", "", 1, k), pls(f1)), ShouldBeNil)
-                                        So(f1.Val, ShouldEqual, 100)
+                                        f := &Foo{}
+                                        getOne(rds, rds.NewKey("Foo", "", 1, k), f)
+                                        So(f.Val, ShouldEqual, 100)
 
-                                        f2 := &Foo{}
-                                        So(rds.Get(rds.NewKey("Foo", "", 2, k), pls(f2)), ShouldBeNil)
-                                        So(f2.Val, ShouldEqual, 200)
+                                        getOne(rds, rds.NewKey("Foo", "", 2, k), f)
+                                        So(f.Val, ShouldEqual, 200)
                                 })
 
                                 Convey("Deletes work too", func() {
                                         err := rds.RunInTransaction(func(c context.Context) error {
                                                 rds := rdsS.Get(c)
                                                 So(rds, ShouldNotBeNil)
-                                                So(rds.Delete(k), ShouldBeNil)
+                                                delOne(rds, k)
                                                 return nil
                                         }, nil)
                                         So(err, ShouldBeNil)
-                                        So(rds.Get(k, nil), ShouldEqual, rdsS.ErrNoSuchEntity)
+                                        _, err = getOnePM(rds, k)
+                                        So(err, ShouldEqual, rdsS.ErrNoSuchEntity)
                                 })
 
                                 Convey("A Get counts against your group count", func() {
                                         err := rds.RunInTransaction(func(c context.Context) error {
                                                 rds := rdsS.Get(c)
-                                                So(rds.Get(rds.NewKey("Foo", "", 20, nil), nil), ShouldEqual, rdsS.ErrNoSuchEntity)
-                                                So(rds.Get(k, nil).Error(), ShouldContainSubstring, "cross-group")
+
+                                                _, err := getOnePM(rds, rds.NewKey("Foo", "", 20, nil))
+                                                So(err, ShouldEqual, rdsS.ErrNoSuchEntity)
+
+                                                err = rds.GetMulti([]rdsS.Key{k}, func(_ rdsS.PropertyMap, err error) {
+                                                        So(err, ShouldBeNil)
+                                                })
+                                                So(err.Error(), ShouldContainSubstring, "cross-group")
                                                 return nil
                                         }, nil)
                                         So(err, ShouldBeNil)
                                 })
 
                                 Convey("Get takes a snapshot", func() {
                                         err := rds.RunInTransaction(func(c context.Context) error {
                                                 txnDS := rdsS.Get(c)
                                                 So(txnDS, ShouldNotBeNil)
 
-                                                So(txnDS.Get(k, pls(f)), ShouldBeNil)
+                                                getOne(txnDS, k, f)
                                                 So(f.Val, ShouldEqual, 10)
 
                                                 // Don't ever do this in a real program unless you want to guarantee
                                                 // a failed transaction :)
                                                 f.Val = 11
-                                                _, err := rds.Put(k, pls(f))
-                                                So(err, ShouldBeNil)
+                                                putOne(rds, k, f)
 
-                                                So(txnDS.Get(k, pls(f)), ShouldBeNil)
+                                                getOne(txnDS, k, f)
                                                 So(f.Val, ShouldEqual, 10)
 
                                                 return nil
                                         }, nil)
                                         So(err, ShouldBeNil)
 
                                         f := &Foo{}
-                                        So(rds.Get(k, pls(f)), ShouldBeNil)
+                                        getOne(rds, k, f)
                                         So(f.Val, ShouldEqual, 11)
                                 })
 
                                 Convey("and snapshots are consistent even after Puts", func() {
                                         err := rds.RunInTransaction(func(c context.Context) error {
                                                 txnDS := rdsS.Get(c)
                                                 So(txnDS, ShouldNotBeNil)
 
                                                 f := &Foo{}
-                                                So(txnDS.Get(k, pls(f)), ShouldBeNil)
+                                                getOne(txnDS, k, f)
                                                 So(f.Val, ShouldEqual, 10)
 
                                                 // Don't ever do this in a real program unless you want to guarantee
                                                 // a failed transaction :)
                                                 f.Val = 11
+                                                putOne(rds, k, f)
 
-                                                _, err := rds.Put(k, pls(f))
-                                                So(err, ShouldBeNil)
-
-                                                So(txnDS.Get(k, pls(f)), ShouldBeNil)
+                                                getOne(txnDS, k, f)
                                                 So(f.Val, ShouldEqual, 10)
 
                                                 f.Val = 20
-                                                _, err = txnDS.Put(k, pls(f))
-                                                So(err, ShouldBeNil)
+                                                putOne(txnDS, k, f)
 
-                                                So(txnDS.Get(k, pls(f)), ShouldBeNil)
+                                                getOne(txnDS, k, f)
                                                 So(f.Val, ShouldEqual, 10) // still gets 10
 
                                                 return nil
                                         }, nil)
                                         So(err.Error(), ShouldContainSubstring, "concurrent")
 
                                         f := &Foo{}
-                                        So(rds.Get(k, pls(f)), ShouldBeNil)
+                                        getOne(rds, k, f)
                                         So(f.Val, ShouldEqual, 11)
                                 })
 
                                 Convey("Reusing a transaction context is bad news", func() {
                                         k := rds.NewKey("Foo", "", 1, nil)
                                         txnDS := rdsS.Interface(nil)
                                         err := rds.RunInTransaction(func(c context.Context) error {
                                                 txnDS = rdsS.Get(c)
-                                                So(txnDS.Get(k, rdsS.PropertyMap{}), ShouldBeNil)
+                                                getOnePM(txnDS, k)
                                                 return nil
                                         }, nil)
                                         So(err, ShouldBeNil)
-                                        So(txnDS.Get(k, rdsS.PropertyMap{}).Error(), ShouldContainSubstring, "expired")
+                                        err = txnDS.GetMulti([]rdsS.Key{k}, func(_ rdsS.PropertyMap, err error) {
+                                                So(err, ShouldBeNil)
+                                        })
+                                        So(err.Error(), ShouldContainSubstring, "expired")
                                 })
 
                                 Convey("Nested transactions are rejected", func() {
                                         err := rds.RunInTransaction(func(c context.Context) error {
                                                 err := rdsS.Get(c).RunInTransaction(func(c context.Context) error {
                                                         panic("noooo")
                                                 }, nil)
                                                 So(err.Error(), ShouldContainSubstring, "nested transactions")
                                                 return nil
                                         }, nil)
                                         So(err, ShouldBeNil)
                                 })
 
                                 Convey("Concurrent transactions only accept one set of changes", func() {
                                         // Note: I think this implementation is actually /slightly/ wrong.
                                         // Accorting to my read of the docs for appengine, when you open a
                                         // transaction it actually (essentially) holds a reference to the
                                         // entire datastore. Our implementation takes a snapshot of the
                                         // entity group as soon as something observes/affects it.
                                         //
                                         // That said... I'm not sure if there's really a semantic difference.
                                         err := rds.RunInTransaction(func(c context.Context) error {
                                                 txnDS := rdsS.Get(c)
                                                 f := &Foo{Val: 21}
-                                                _, err = txnDS.Put(k, pls(f))
-                                                So(err, ShouldBeNil)
+                                                putOne(txnDS, k, f)
 
                                                 err := rds.RunInTransaction(func(c context.Context) error {
                                                         txnDS := rdsS.Get(c)
                                                         f := &Foo{Val: 27}
-                                                        _, err := txnDS.Put(k, pls(f))
-                                                        So(err, ShouldBeNil)
+                                                        putOne(txnDS, k, f)
                                                         return nil
                                                 }, nil)
                                                 So(err, ShouldBeNil)
 
                                                 return nil
                                         }, nil)
                                         So(err.Error(), ShouldContainSubstring, "concurrent")
 
                                         f := &Foo{}
-                                        So(rds.Get(k, pls(f)), ShouldBeNil)
+                                        getOne(rds, k, f)
                                         So(f.Val, ShouldEqual, 27)
                                 })
 
                                 Convey("XG", func() {
                                         Convey("Modifying two groups with XG=false is invalid", func() {
                                                 err := rds.RunInTransaction(func(c context.Context) error {
                                                         rds := rdsS.Get(c)
                                                         f := &Foo{Val: 200}
-                                                        _, err := rds.Put(k, pls(f))
-                                                        So(err, ShouldBeNil)
+                                                        putOne(rds, k, f)
 
-                                                        _, err = rds.Put(rds.NewKey("Foo", "", 2, nil), pls(f))
+                                                        _, err := putOneErr(rds, rds.NewKey("Foo", "", 2, nil), f)
                                                         So(err.Error(), ShouldContainSubstring, "cross-group")
                                                         return err
                                                 }, nil)
                                                 So(err.Error(), ShouldContainSubstring, "cross-group")
                                         })
 
                                         Convey("Modifying >25 groups with XG=true is invald", func() {
                                                 err := rds.RunInTransaction(func(c context.Context) error {
                                                         rds := rdsS.Get(c)
                                                         for i := int64(1); i < 26; i++ {
                                                                 k := rds.NewKey("Foo", "", i, nil)
                                                                 f := &Foo{Val: 200}
-                                                                _, err := rds.Put(k, pls(f))
-                                                                So(err, ShouldBeNil)
+                                                                putOne(rds, k, f)
                                                         }
                                                         f := &Foo{Val: 200}
-                                                        _, err := rds.Put(rds.NewKey("Foo", "", 27, nil), pls(f))
+                                                        _, err := putOneErr(rds, rds.NewKey("Foo", "", 27, nil), f)
                                                         So(err.Error(), ShouldContainSubstring, "too many entity groups")
                                                         return err
                                                 }, &rdsS.TransactionOptions{XG: true})
                                                 So(err.Error(), ShouldContainSubstring, "too many entity groups")
                                         })
                                 })
 
                                 Convey("Errors and panics", func() {
                                         Convey("returning an error aborts", func() {
                                                 err := rds.RunInTransaction(func(c context.Context) error {
                                                         rds := rdsS.Get(c)
                                                         f := &Foo{Val: 200}
-                                                        _, err := rds.Put(k, pls(f))
-                                                        So(err, ShouldBeNil)
+                                                        putOne(rds, k, f)
 
                                                         return fmt.Errorf("thingy")
                                                 }, nil)
                                                 So(err.Error(), ShouldEqual, "thingy")
 
                                                 f := &Foo{}
-                                                So(rds.Get(k, pls(f)), ShouldBeNil)
+                                                getOne(rds, k, f)
                                                 So(f.Val, ShouldEqual, 10)
                                         })
 
                                         Convey("panicing aborts", func() {
                                                 So(func() {
                                                         rds.RunInTransaction(func(c context.Context) error {
                                                                 rds := rdsS.Get(c)
                                                                 f := &Foo{Val: 200}
-                                                                _, err := rds.Put(k, pls(f))
-                                                                So(err, ShouldBeNil)
+                                                                putOne(rds, k, f)
                                                                 panic("wheeeeee")
                                                         }, nil)
                                                 }, ShouldPanic)
 
                                                 f := &Foo{}
-                                                So(rds.Get(k, pls(f)), ShouldBeNil)
+                                                getOne(rds, k, f)
                                                 So(f.Val, ShouldEqual, 10)
                                         })
                                 })
                         })
                 })
 
         })
 }
 
 const MaxUint = ^uint(0)
@@ skipping 145 matching lines @@
                         })
                         Convey("kindless with decending-__key__ orders", func() {
                                 q := rds.NewQuery("").Order("-__key__")
                                 qi := q.(*queryImpl).checkCorrectness("", false)
                                 So(qi.err.Error(), ShouldContainSubstring, "kind is required for all orders")
                         })
                 })
 
         })
 }