Add test for EphemeralContainerCommon struct tags

The tags for type EphemeralContainerCommon should be kept in sync with
those of type Container.

Co-authored-by: Jordan Liggitt <liggitt@google.com>

pkg/apis/core/types_test.go

@@ -0,0 +1,41 @@
+/*
+Copyright 2021 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package core
+
+import (
+	"reflect"
+	"testing"
+)
+
+// TestEphemeralContainer ensures that the tags of Container and EphemeralContainerCommon are kept in sync.
+func TestEphemeralContainer(t *testing.T) {
+	ephemeralType := reflect.TypeOf(EphemeralContainerCommon{})
+	containerType := reflect.TypeOf(Container{})
+
+	ephemeralFields := ephemeralType.NumField()
+	containerFields := containerType.NumField()
+	if containerFields != ephemeralFields {
+		t.Fatalf("%v has %d fields, %v has %d fields", ephemeralType, ephemeralFields, containerType, containerFields)
+	}
+	for i := 0; i < ephemeralFields; i++ {
+		ephemeralField := ephemeralType.Field(i)
+		containerField := containerType.Field(i)
+		if !reflect.DeepEqual(ephemeralField, containerField) {
+			t.Errorf("field %v differs:\n\t%#v\n\t%#v", ephemeralField.Name, ephemeralField, containerField)
+		}
+	}
+}