Fix self linking of objects returned in lists.

pkg/runtime/helper.go

@@ -23,6 +23,11 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/conversion"
 )
 
+func IsListType(obj Object) bool {
+	_, err := GetItemsPtr(obj)
+	return err == nil
+}
+
 // GetItemsPtr returns a pointer to the list object's Items member.
 // If 'list' doesn't have an Items member, it's not really a list type
 // and an error will be returned.

pkg/runtime/helper_test.go

@@ -26,6 +26,21 @@ import (
 	"github.com/google/gofuzz"
 )
 
+func TestIsList(t *testing.T) {
+	tests := []struct {
+		obj    runtime.Object
+		isList bool
+	}{
+		{&api.PodList{}, true},
+		{&api.Pod{}, false},
+	}
+	for _, item := range tests {
+		if e, a := item.isList, runtime.IsListType(item.obj); e != a {
+			t.Errorf("%v: Expected %v, got %v", reflect.TypeOf(item.obj), e, a)
+		}
+	}
+}
+
 func TestExtractList(t *testing.T) {
 	pl := &api.PodList{
 		Items: []api.Pod{