datastore: Update AllocateIDs to take keys.

service/datastore/checkfilter_test.go

Index: service/datastore/checkfilter_test.go
diff --git a/service/datastore/checkfilter_test.go b/service/datastore/checkfilter_test.go
index 9f45b25a22147a2166c274dd60484c55ae130a9b..e2bf54dd18ab5245a6ebc7e1ea4254567bf859a1 100644
--- a/service/datastore/checkfilter_test.go
+++ b/service/datastore/checkfilter_test.go
@@ -10,8 +10,10 @@ import (
 	"testing"
 
 	"github.com/luci/gae/service/info"
-	. "github.com/smartystreets/goconvey/convey"
+	"github.com/luci/luci-go/common/errors"
 	"golang.org/x/net/context"
+
+	. "github.com/smartystreets/goconvey/convey"
 )
 
 type fakeRDS struct{ RawInterface }
@@ -30,6 +32,28 @@ func TestCheckFilter(t *testing.T) {
 		rds := GetRaw(c) // has checkFilter
 		So(rds, ShouldNotBeNil)
 
+		Convey("AllocateIDs", func() {
+			Convey("Will return nil if no keys are supplied.", func() {
+				So(rds.AllocateIDs(nil), ShouldBeNil)
+			})
+
+			Convey("Will reject keys that are not PartialValid.", func() {
+				k := NewKey("s~aid", "ns", "", "", 0, nil) // No Kind.
+				So(k.PartialValid("s~aid", "ns"), ShouldBeFalse)
+
+				err := rds.AllocateIDs([]*Key{k})
+				So(err, ShouldResemble, errors.MultiError{ErrInvalidKey})
+			})
+
+			Convey("Will reject keys with non-homogenous entity types.", func() {
+				k0 := NewKey("s~aid", "ns", "OneKind", "", 0, nil)
+				k1 := NewKey("s~aid", "ns", "OtherKind", "", 0, nil)
+
+				err := rds.AllocateIDs([]*Key{k0, k1})
+				So(err, ShouldResemble, errors.MultiError{nil, ErrInvalidKey})
+			})
+		})
+
 		Convey("RunInTransaction", func() {
 			So(rds.RunInTransaction(nil, nil).Error(), ShouldContainSubstring, "is nil")
 			hit := false