Sort revisions in rollout history as integers

Previously keys were sorted as strings, thus it was possible
to see such order as 1, 10, 2, 3, 4, 5.

Ints64 helper implemented in util/slice module to sort []int64

pkg/kubectl/history.go

@@ -19,8 +19,6 @@ package kubectl
 import (
 	"fmt"
 	"io"
-	"sort"
-	"strconv"
 
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/api/meta"
@@ -29,7 +27,7 @@ import (
 	clientset "k8s.io/kubernetes/pkg/client/clientset_generated/internalclientset"
 	"k8s.io/kubernetes/pkg/runtime"
 	deploymentutil "k8s.io/kubernetes/pkg/util/deployment"
-	"k8s.io/kubernetes/pkg/util/errors"
+	sliceutil "k8s.io/kubernetes/pkg/util/slice"
 )
 
 const (
@@ -103,30 +101,24 @@ func PrintRolloutHistory(historyInfo HistoryInfo, resource, name string) (string
 		return fmt.Sprintf("No rollout history found in %s %q", resource, name), nil
 	}
 	// Sort the revisionToChangeCause map by revision
-	var revisions []string
-	for k := range historyInfo.RevisionToTemplate {
-		revisions = append(revisions, strconv.FormatInt(k, 10))
+	var revisions []int64
+	for r := range historyInfo.RevisionToTemplate {
+		revisions = append(revisions, r)
 	}
-	sort.Strings(revisions)
+	sliceutil.SortInts64(revisions)
 
 	return tabbedString(func(out io.Writer) error {
 		fmt.Fprintf(out, "%s %q:\n", resource, name)
 		fmt.Fprintf(out, "REVISION\tCHANGE-CAUSE\n")
-		errs := []error{}
 		for _, r := range revisions {
 			// Find the change-cause of revision r
-			r64, err := strconv.ParseInt(r, 10, 64)
-			if err != nil {
-				errs = append(errs, err)
-				continue
-			}
-			changeCause := historyInfo.RevisionToTemplate[r64].Annotations[ChangeCauseAnnotation]
+			changeCause := historyInfo.RevisionToTemplate[r].Annotations[ChangeCauseAnnotation]
 			if len(changeCause) == 0 {
 				changeCause = "<none>"
 			}
-			fmt.Fprintf(out, "%s\t%s\n", r, changeCause)
+			fmt.Fprintf(out, "%d\t%s\n", r, changeCause)
 		}
-		return errors.NewAggregate(errs)
+		return nil
 	})
 }
 

pkg/util/slice/slice.go

@@ -48,3 +48,14 @@ func ShuffleStrings(s []string) []string {
 	}
 	return shuffled
 }
+
+// Int64Slice attaches the methods of Interface to []int64,
+// sorting in increasing order.
+type Int64Slice []int64
+
+func (p Int64Slice) Len() int           { return len(p) }
+func (p Int64Slice) Less(i, j int) bool { return p[i] < p[j] }
+func (p Int64Slice) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
+
+// Sorts []int64 in increasing order
+func SortInts64(a []int64) { sort.Sort(Int64Slice(a)) }

pkg/util/slice/slice_test.go

@@ -68,3 +68,12 @@ func TestShuffleStrings(t *testing.T) {
 		}
 	}
 }
+
+func TestSortInts64(t *testing.T) {
+	src := []int64{10, 1, 2, 3, 4, 5, 6}
+	expected := []int64{1, 2, 3, 4, 5, 6, 10}
+	SortInts64(src)
+	if !reflect.DeepEqual(src, expected) {
+		t.Errorf("func Ints64 didnt sort correctly, %v !- %v", src, expected)
+	}
+}