Fix error message from KeyForObj when passing an invalid struct.

service/datastore/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.
 
 // adapted from github.com/golang/appengine/datastore
 
 package datastore
 
 import (
         "fmt"
@@ skipping 162 matching lines @@
                 if f.Kind == "" {
                         So(ret.SetMeta("kind", "FakePLS"), ShouldBeNil)
                 } else {
                         So(ret.SetMeta("kind", f.Kind), ShouldBeNil)
                 }
                 So(ret.SetMeta("assertExtra", true), ShouldBeNil)
         }
         return ret, nil
 }
 
-func (f *FakePLS) GetMetaDefault(key string, dflt interface{}) interface{} {
-        return GetMetaDefaultImpl(f.GetMeta, key, dflt)
-}
-
 func (f *FakePLS) GetMeta(key string) (interface{}, error) {
         if f.failGetMeta {
                 return nil, errors.New("FakePLS.GetMeta")
         }
         switch key {
         case "id":
                 if f.StringID != "" {
                         return f.StringID, nil
                 }
                 return f.IntID, nil
@@ skipping 12 matching lines @@
                 So(ret.SetMeta("id", id), ShouldBeNil)
         }
         if kind, err := f.GetMeta("kind"); err != nil {
                 So(ret.SetMeta("kind", kind), ShouldBeNil)
         }
         return ret
 }
 
 func (f *FakePLS) SetMeta(key string, val interface{}) error {
         if f.failSetMeta {
-                return errors.New("FakePL.SetMeta")
+                return errors.New("FakePLS.SetMeta")
         }
         if key == "id" {
                 switch x := val.(type) {
                 case int64:
                         f.IntID = x
                 case string:
                         f.StringID = x
                 }
                 return nil
         }
         if key == "kind" {
                 f.Kind = val.(string)
                 return nil
         }
         return ErrMetaFieldUnset
 }
 
 func (f *FakePLS) Problem() error {
         if f.failProblem {
                 return errors.New("FakePLS.Problem")
         }
         return nil
 }
 
 type MGSWithNoKind struct {
         S string
 }
 
-func (s *MGSWithNoKind) GetMetaDefault(key string, dflt interface{}) interface{} {
-        return GetMetaDefaultImpl(s.GetMeta, key, dflt)
-}
-
 func (s *MGSWithNoKind) GetMeta(key string) (interface{}, error) {
         return nil, ErrMetaFieldUnset
 }
 
 func (s *MGSWithNoKind) GetAllMeta() PropertyMap {
         return PropertyMap{}
 }
 
 func (s *MGSWithNoKind) SetMeta(key string, val interface{}) error {
         return ErrMetaFieldUnset
@@ skipping 74 matching lines @@
                         })
 
                 })
 
                 Convey("bad", func() {
                         Convey("a propmap without $kind", func() {
                                 pm := PropertyMap{}
                                 So(pm.SetMeta("id", 100), ShouldBeNil)
                                 So(func() { ds.KeyForObj(pm) }, ShouldPanic)
                         })
+
+                        Convey("a bad object", func() {
+                                type BadObj struct {
+                                        ID int64 `gae:"$id"`
+
+                                        NonSerializableField complex64
+                                }
+
+                                _, err := ds.KeyForObjErr(&BadObj{ID: 1})
+                                So(err, ShouldErrLike, `field "NonSerializableField" has invalid type: complex64`)
+                        })
                 })
         })
 }
 
 func TestPut(t *testing.T) {
         t.Parallel()
 
         Convey("Test Put/PutMulti", t, func() {
                 c := info.Set(context.Background(), fakeInfo{})
                 c = SetRawFactory(c, fakeDatastoreFactory)
                 ds := Get(c)
 
                 Convey("bad", func() {
                         Convey("static can't serialize", func() {
                                 bss := []badStruct{{}, {}}
-                                So(ds.PutMulti(bss).Error(), ShouldContainSubstring, "invalid PutMulti input")
+                                So(ds.PutMulti(bss), ShouldErrLike, "invalid PutMulti input")
                         })
 
                         Convey("static ptr can't serialize", func() {
                                 bss := []*badStruct{{}, {}}
-                                So(ds.PutMulti(bss).Error(), ShouldContainSubstring, "invalid PutMulti input")
+                                So(ds.PutMulti(bss), ShouldErrLike, "invalid PutMulti input")
                         })
 
                         Convey("static bad type (non-slice)", func() {
-                                So(ds.PutMulti(100).Error(), ShouldContainSubstring, "invalid PutMulti input")
+                                So(ds.PutMulti(100), ShouldErrLike, "invalid PutMulti input")
                         })
 
                         Convey("static bad type (slice of bad type)", func() {
-                                So(ds.PutMulti([]int{}).Error(), ShouldContainSubstring, "invalid PutMulti input")
+                                So(ds.PutMulti([]int{}), ShouldErrLike, "invalid PutMulti input")
                         })
 
                         Convey("dynamic can't serialize", func() {
                                 fplss := []FakePLS{{failSave: true}, {}}
-                                So(ds.PutMulti(fplss).Error(), ShouldContainSubstring, "FakePLS.Save")
+                                So(ds.PutMulti(fplss), ShouldErrLike, "FakePLS.Save")
                         })
 
                         Convey("can't get keys", func() {
                                 fplss := []FakePLS{{failGetMeta: true}, {}}
-                                So(ds.PutMulti(fplss).Error(), ShouldContainSubstring, "unable to extract $kind")
+                                So(ds.PutMulti(fplss), ShouldErrLike, "FakePLS.GetMeta")
                         })
 
                         Convey("get single error for RPC failure", func() {
                                 fplss := []FakePLS{{Kind: "FailAll"}, {}}
-                                So(ds.PutMulti(fplss).Error(), ShouldEqual, "PutMulti fail all")
+                                So(ds.PutMulti(fplss), ShouldErrLike, "PutMulti fail all")
                         })
 
                         Convey("get multi error for individual failures", func() {
                                 fplss := []FakePLS{{}, {Kind: "Fail"}}
                                 So(ds.PutMulti(fplss), ShouldResemble, errors.MultiError{nil, errors.New("PutMulti fail")})
                         })
 
                         Convey("put with non-modifyable type is an error", func() {
                                 cs := CommonStruct{}
-                                So(ds.Put(cs).Error(), ShouldContainSubstring, "invalid Put input type")
+                                So(ds.Put(cs), ShouldErrLike, "invalid Put input type")
                         })
 
                         Convey("struct with no $kind is an error", func() {
                                 s := MGSWithNoKind{}
-                                So(ds.Put(&s).Error(), ShouldContainSubstring, "unable to extract $kind")
+                                So(ds.Put(&s), ShouldErrLike, "unable to extract $kind")
                         })
                 })
 
                 Convey("ok", func() {
                         Convey("[]S", func() {
                                 css := make([]CommonStruct, 7)
                                 for i := range css {
                                         if i == 4 {
                                                 css[i].ID = 200
                                         }
@@ skipping 181 matching lines @@
 
         Convey("Test Get/GetMulti", t, func() {
                 c := info.Set(context.Background(), fakeInfo{})
                 c = SetRawFactory(c, fakeDatastoreFactory)
                 ds := Get(c)
                 So(ds, ShouldNotBeNil)
 
                 Convey("bad", func() {
                         Convey("static can't serialize", func() {
                                 toGet := []badStruct{{}, {}}
-                                So(ds.GetMulti(toGet).Error(), ShouldContainSubstring, "invalid GetMulti input")
+                                So(ds.GetMulti(toGet), ShouldErrLike, "invalid GetMulti input")
                         })
 
                         Convey("can't get keys", func() {
                                 fplss := []FakePLS{{failGetMeta: true}, {}}
-                                So(ds.GetMulti(fplss).Error(), ShouldContainSubstring, "unable to extract $kind")
+                                So(ds.GetMulti(fplss), ShouldErrLike, "FakePLS.GetMeta")
                         })
 
                         Convey("get single error for RPC failure", func() {
                                 fplss := []FakePLS{
                                         {IntID: 1, Kind: "FailAll"},
                                         {IntID: 2},
                                 }
                                 So(ds.GetMulti(fplss).Error(), ShouldEqual, "GetMulti fail all")
                         })
 
                         Convey("get multi error for individual failures", func() {
                                 fplss := []FakePLS{{IntID: 1}, {IntID: 2, Kind: "Fail"}}
                                 So(ds.GetMulti(fplss), ShouldResemble, errors.MultiError{nil, errors.New("GetMulti fail")})
                         })
 
                         Convey("get with non-modifiable type is an error", func() {
                                 cs := CommonStruct{}
-                                So(ds.Get(cs).Error(), ShouldContainSubstring, "invalid Get input type")
+                                So(ds.Get(cs), ShouldErrLike, "invalid Get input type")
                         })
 
-                        Convey("failure to save metadata is an issue too", func() {
-                                cs := &FakePLS{failGetMeta: true}
-                                So(ds.Get(cs).Error(), ShouldContainSubstring, "unable to extract $kind")
+                        Convey("failure to save metadata is no problem though", func() {
+                                // It just won't save the key
+                                cs := &FakePLS{IntID: 10, failSetMeta: true}
+                                So(ds.Get(cs), ShouldBeNil)
                         })
                 })
 
                 Convey("ok", func() {
                         Convey("Get", func() {
                                 cs := &CommonStruct{ID: 1}
                                 So(ds.Get(cs), ShouldBeNil)
                                 So(cs.Value, ShouldEqual, 1)
                         })
 
@@ skipping 21 matching lines @@
         Convey("Test GetAll", t, func() {
                 c := info.Set(context.Background(), fakeInfo{})
                 c = SetRawFactory(c, fakeDatastoreFactory)
                 ds := Get(c)
                 So(ds, ShouldNotBeNil)
 
                 q := NewQuery("").Limit(5)
 
                 Convey("bad", func() {
                         Convey("nil target", func() {
-                                So(ds.GetAll(q, (*[]PropertyMap)(nil)).Error(), ShouldContainSubstring, "dst: <nil>")
+                                So(ds.GetAll(q, (*[]PropertyMap)(nil)), ShouldErrLike, "dst: <nil>")
                         })
 
                         Convey("bad type", func() {
                                 output := 100
-                                So(ds.GetAll(q, &output).Error(), ShouldContainSubstring, "invalid GetAll input type")
+                                So(ds.GetAll(q, &output), ShouldErrLike, "invalid GetAll input type")
                         })
 
                         Convey("bad type (non pointer)", func() {
-                                So(ds.GetAll(q, "moo").Error(), ShouldContainSubstring, "must have a ptr-to-slice")
+                                So(ds.GetAll(q, "moo"), ShouldErrLike, "must have a ptr-to-slice")
                         })
 
                         Convey("bad type (underspecified)", func() {
                                 output := []PropertyLoadSaver(nil)
-                                So(ds.GetAll(q, &output).Error(), ShouldContainSubstring, "invalid GetAll input type")
+                                So(ds.GetAll(q, &output), ShouldErrLike, "invalid GetAll input type")
                         })
                 })
 
                 Convey("ok", func() {
                         Convey("*[]S", func() {
                                 output := []CommonStruct(nil)
                                 So(ds.GetAll(q, &output), ShouldBeNil)
                                 So(len(output), ShouldEqual, 5)
                                 for i, o := range output {
                                         So(o.ID, ShouldEqual, i+1)
@@ skipping 80 matching lines @@
                 ds := Get(c)
                 So(ds, ShouldNotBeNil)
 
                 q := NewQuery("kind").Limit(5)
 
                 Convey("bad", func() {
                         assertBadTypePanics := func(cb interface{}) {
                                 defer func() {
                                         err, _ := recover().(error)
                                         So(err, ShouldNotBeNil)
-                                        So(err.Error(), ShouldContainSubstring,
-                                                "cb does not match the required callback signature")
+                                        So(err, ShouldErrLike, "cb does not match the required callback signature")
                                 }()
                                 So(ds.Run(q, cb), ShouldBeNil)
                         }
 
                         Convey("not a function", func() {
                                 assertBadTypePanics("I am a potato")
                         })
 
                         Convey("bad proto type", func() {
                                 assertBadTypePanics(func(v int, _ CursorCB) bool {
@@ skipping 112 matching lines @@
                                 So(ds.Run(q, func(k *Key, _ CursorCB) bool {
                                         So(k.IntID(), ShouldEqual, i+1)
                                         i++
                                         return true
                                 }), ShouldBeNil)
                         })
 
                 })
         })
 }