Don't filter "Stop" error in raw interface.

impl/memory/gkvlite_iter_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 (
         "bytes"
         "testing"
 
@@ skipping 196 matching lines @@
                         defs := []*iterDefinition{
                                 {c: c, prefix: mkNum(1), prefixLen: len(mkNum(1)), start: mkNum(2), end: mkNum(7)},
                                 {c: c, prefix: mkNum(1), prefixLen: len(mkNum(1)), start: mkNum(2), end: mkNum(7)},
                         }
 
                         i := 1
                         So(multiIterate(defs, func(suffix []byte) error {
                                 So(readNum(suffix), ShouldEqual, vals[i][1])
                                 i++
                                 return nil
-                        }), ShouldBeNil)
+                        }), shouldBeSuccessful)
 
                         So(i, ShouldEqual, 3)
                 })
 
                 Convey("can make empty iteration", func() {
                         // get just the (20, *) (doesn't exist)
                         defs := []*iterDefinition{
                                 {c: c, prefix: mkNum(20)},
                                 {c: c, prefix: mkNum(20)},
                         }
 
                         i := 0
                         So(multiIterate(defs, func(suffix []byte) error {
                                 panic("never")
-                        }), ShouldBeNil)
+                        }), shouldBeSuccessful)
 
                         So(i, ShouldEqual, 0)
                 })
 
                 Convey("can join (other, val, val)", func() {
                         // 'other' must start with 20, 'vals' must start with 1
                         // no range constraints
                         defs := []*iterDefinition{
                                 {c: c2, prefix: mkNum(20)},
                                 {c: c, prefix: mkNum(1)},
                                 {c: c, prefix: mkNum(1)},
                         }
 
                         expect := []int64{2, 4}
                         i := 0
                         So(multiIterate(defs, func(suffix []byte) error {
                                 So(readNum(suffix), ShouldEqual, expect[i])
                                 i++
                                 return nil
-                        }), ShouldBeNil)
+                        }), shouldBeSuccessful)
                 })
 
                 Convey("Can stop early", func() {
                         defs := []*iterDefinition{
                                 {c: c, prefix: mkNum(1), prefixLen: len(mkNum(1))},
                                 {c: c, prefix: mkNum(1), prefixLen: len(mkNum(1))},
                         }
 
                         i := 0
                         So(multiIterate(defs, func(suffix []byte) error {
                                 So(readNum(suffix), ShouldEqual, vals[i][1])
                                 i++
                                 return nil
-                        }), ShouldBeNil)
+                        }), shouldBeSuccessful)
                         So(i, ShouldEqual, 5)
 
                         i = 0
                         So(multiIterate(defs, func(suffix []byte) error {
                                 So(readNum(suffix), ShouldEqual, vals[i][1])
                                 i++
                                 return datastore.Stop
-                        }), ShouldBeNil)
+                        }), shouldBeSuccessful)
                         So(i, ShouldEqual, 1)
                 })
 
         })
 
 }