add Replicaset -> ReplicationController conversion test

and ensure we account for fields that are only supported by ReplicaSet

pkg/apis/core/v1/conversion_test.go

@@ -329,7 +329,106 @@ func TestReplicationControllerConversion(t *testing.T) {
 		if !apiequality.Semantic.DeepEqual(in, out) {
 			instr, _ := json.MarshalIndent(in, "", "  ")
 			outstr, _ := json.MarshalIndent(out, "", "  ")
-			t.Errorf("RC-RS conversion round-trip failed:\nin:\n%s\nout:\n%s", instr, outstr)
+			t.Errorf("RC-RS conversion round-trip failed:\nin:\n%s\nout:\n%s\ndiff:\n%s", instr, outstr, cmp.Diff(in, out))
+		}
+	}
+}
+
+func TestReplicaSetConversion(t *testing.T) {
+	inputs := []*apps.ReplicaSet{
+		{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      "name",
+				Namespace: "namespace",
+				Labels:    map[string]string{"foo": "bar", "bar": "foo"}, // labels have to be defined everywhere not to trigger RC defaulting
+			},
+			Spec: apps.ReplicaSetSpec{
+				Replicas:        1,
+				MinReadySeconds: 32,
+				Selector: &metav1.LabelSelector{
+					MatchLabels: map[string]string{"foo": "bar", "bar": "foo"},
+				},
+				Template: core.PodTemplateSpec{
+					ObjectMeta: metav1.ObjectMeta{
+						Labels: map[string]string{"foo": "bar", "bar": "foo"},
+					},
+					Spec: core.PodSpec{
+						Containers: []core.Container{
+							{
+								Name:  "container",
+								Image: "image",
+							},
+						},
+					},
+				},
+			},
+			Status: apps.ReplicaSetStatus{
+				Replicas:             1,
+				FullyLabeledReplicas: 2,
+				ReadyReplicas:        3,
+				AvailableReplicas:    4,
+				TerminatingReplicas:  nil, // ReplicationController does not support .status.terminatingReplicas
+				ObservedGeneration:   5,
+				Conditions: []apps.ReplicaSetCondition{
+					{
+						Type:               apps.ReplicaSetReplicaFailure,
+						Status:             core.ConditionTrue,
+						LastTransitionTime: metav1.NewTime(time.Unix(123456789, 0)),
+						Reason:             "Reason",
+						Message:            "Message",
+					},
+				},
+			},
+		},
+	}
+
+	// Add some fuzzed ReplicaSets.
+	apiObjectFuzzer := fuzzer.FuzzerFor(fuzzer.MergeFuzzerFuncs(metafuzzer.Funcs, corefuzzer.Funcs), rand.NewSource(152), legacyscheme.Codecs)
+	for i := 0; i < 100; i++ {
+		rs := &apps.ReplicaSet{}
+		apiObjectFuzzer.Fill(rs)
+		// if we have labels, they have to be set to satisfy RC defaulting
+		if labels := rs.Spec.Template.Labels; len(labels) > 0 {
+			rs.Labels = labels
+
+			// forcefully set label selector, since the RC has only partial selector support (MatchLabels)
+			rs.Spec.Selector = &metav1.LabelSelector{
+				MatchLabels: labels,
+			}
+		} else {
+			rs.Spec.Selector = nil
+		}
+
+		// ReplicationController does not support .status.terminatingReplicas
+		if rs.Status.TerminatingReplicas != nil {
+			rs.Status.TerminatingReplicas = nil
+		}
+		inputs = append(inputs, rs)
+	}
+
+	// Round-trip the input RSs before converting to RC.
+	for i := range inputs {
+		inputs[i] = roundTripRS(t, inputs[i])
+	}
+
+	for _, in := range inputs {
+		rc := &v1.ReplicationController{}
+		// Use in.DeepCopy() to avoid sharing pointers with `in`.
+		if err := corev1.Convert_apps_ReplicaSet_To_v1_ReplicationController(in.DeepCopy(), rc, nil); err != nil {
+			t.Errorf("can't convert RS to RC: %v", err)
+			continue
+		}
+		// Round-trip RC before converting back to RS.
+		rc = roundTrip(t, rc).(*v1.ReplicationController)
+		out := &apps.ReplicaSet{}
+		if err := corev1.Convert_v1_ReplicationController_To_apps_ReplicaSet(rc, out, nil); err != nil {
+			t.Errorf("can't convert RC to RS: %v", err)
+			continue
+		}
+		if !apiequality.Semantic.DeepEqual(in, out) {
+			instr, _ := json.MarshalIndent(in, "", "  ")
+			outstr, _ := json.MarshalIndent(out, "", "  ")
+			t.Errorf("RS-RC conversion round-trip failed:\nin:\n%s\nout:\n%s\ndiff:\n%s", instr, outstr, cmp.Diff(in, out))
 		}
 	}
 }