You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: empty_dir_test.go
    path of file: ./repos/kubernetes/pkg/volume/emptydir
    
    the code of the file until where you have to start completion: //go:build linux
// +build linux

/*
Copyright 2014 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 emptydir

import (
	"fmt"
	"os"
	"path/filepath"
	"testing"

	v1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/api/resource"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/types"
	utilfeature "k8s.io/apiserver/pkg/util/feature"
	utiltesting "k8s.io/client-go/util/testing"
	featuregatetesting "k8s.io/component-base/featuregate/testing"
	"k8s.io/kubernetes/pkg/features"
	"k8s.io/kubernetes/pkg/volume"
	volumetest "k8s.io/kubernetes/pkg/volume/testing"
	volumeutil "k8s.io/kubernetes/pkg/volume/util"
	"k8s.io/mount-utils"
)

// Construct an instance of a plugin, by name.
func makePluginUnderTest(t *testing.T, plugName, basePath string) volume.VolumePlugin {
	plugMgr := volume.VolumePluginMgr{}
	plugMgr.InitPlugins(ProbeVolumePlugins(), nil /* prober */, volumetest.NewFakeVolumeHost(t, basePath, nil, nil))

	plug, err := plugMgr.FindPluginByName(plugName)
	if err != nil {
		t.Fatal("Can't find the plugin by name")
	}
	return plug
}

func TestCanSupport(t *testing.T) {
	tmpDir, err := utiltesting.MkTmpdir("emptydirTest")
	if err != nil {
		t.Fatalf("can't make a temp dir: %v", err)
	}
	defer os.RemoveAll(tmpDir)
	plug := makePluginUnderTest(t, "kubernetes.io/empty-dir", tmpDir)

	if plug.GetPluginName() != "kubernetes.io/empty-dir" {
		t.Errorf("Wrong name: %s", plug.GetPluginName())
	}
	if !plug.CanSupport(&volume.Spec{Volume: &v1.Volume{VolumeSource: v1.VolumeSource{EmptyDir: &v1.EmptyDirVolumeSource{}}}}) {
		t.Errorf("Expected true")
	}
	if plug.CanSupport(&volume.Spec{Volume: &v1.Volume{VolumeSource: v1.VolumeSource{}}}) {
		t.Errorf("Expected false")
	}
}

type fakeMountDetector struct {
	medium  v1.StorageMedium
	isMount bool
}

func (fake *fakeMountDetector) GetMountMedium(path string, requestedMedium v1.StorageMedium) (v1.StorageMedium, bool, *resource.Quantity, error) {
	return fake.medium, fake.isMount, nil, nil
}

func TestPluginEmptyRootContext(t *testing.T) {
	doTestPlugin(t, pluginTestConfig{
		volumeDirExists:        true,
		readyDirExists:         true,
		medium:                 v1.StorageMediumDefault,
		expectedSetupMounts:    0,
		expectedTeardownMounts: 0})
	doTestPlugin(t, pluginTestConfig{
		volumeDirExists:        false,
		readyDirExists:         false,
		medium:                 v1.StorageMediumDefault,
		expectedSetupMounts:    0,
		expectedTeardownMounts: 0})
	doTestPlugin(t, pluginTestConfig{
		volumeDirExists:        true,
		readyDirExists:         false,
		medium:                 v1.StorageMediumDefault,
		expectedSetupMounts:    0,
		expectedTeardownMounts: 0})
	doTestPlugin(t, pluginTestConfig{
		volumeDirExists:        false,
		readyDirExists:         true,
		medium:                 v1.StorageMediumDefault,
		expectedSetupMounts:    0,
		expectedTeardownMounts: 0})
}

func TestPluginHugetlbfs(t *testing.T) {
	testCases := map[string]struct {
		medium v1.StorageMedium
	}{
		"medium without size": {
			medium: "HugePages",
		},
		"medium with size": {
			medium: "HugePages-2Mi",
		},
	}
	for tcName, tc := range testCases {
		t.Run(tcName, func(t *testing.T) {
			doTestPlugin(t, pluginTestConfig{
				medium:                        tc.medium,
				expectedSetupMounts:           1,
				expectedTeardownMounts:        0,
				shouldBeMountedBeforeTeardown: true,
			})
		})
	}
}

type pluginTestConfig struct {
	medium v1.StorageMedium
	//volumeDirExists indicates whether volumeDir already/still exists before volume setup/teardown
	volumeDirExists bool
	//readyDirExists indicates whether readyDir already/still exists before volume setup/teardown
	readyDirExists                bool
	expectedSetupMounts           int
	shouldBeMountedBeforeTeardown bool
	expectedTeardownMounts        int
}

// doTestPlugin sets up a volume and tears it back down.
func doTestPlugin(t *testing.T, config pluginTestConfig) {
	basePath, err := utiltesting.MkTmpdir("emptydir_volume_test")
	if err != nil {
    
func TestSetupHugepages(t *testing.T) {
	tmpdir, err := os.MkdirTemp("", "TestSetupHugepages")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(tmpdir)

	pageSize2Mi := resource.MustParse("2Mi")

	testCases := map[string]struct {
		path       string
		ed         *emptyDir
		shouldFail bool
	}{
		"Valid: mount expected": {
			path: tmpdir,
			ed: &emptyDir{
				medium: v1.StorageMediumHugePages,
				pod: &v1.Pod{
					Spec: v1.PodSpec{
						Containers: []v1.Container{
							{
								Resources: v1.ResourceRequirements{
									Requests: v1.ResourceList{
										v1.ResourceName("hugepages-2Mi"): resource.MustParse("100Mi"),
									},
								},
							},
						},
					},
				},
				mounter: &mount.FakeMounter{},
				mountDetector: &testMountDetector{
					pageSize: &resource.Quantity{},
					isMnt:    false,
					err:      nil,
				},
			},
			shouldFail: false,
		},
		"Valid: already mounted with correct pagesize": {
			path: tmpdir,
			ed: &emptyDir{
				medium: "HugePages-2Mi",
				pod: &v1.Pod{
					Spec: v1.PodSpec{
						Containers: []v1.Container{
							{
								Resources: v1.ResourceRequirements{
									Requests: v1.ResourceList{
										v1.ResourceName("hugepages-2Mi"): resource.MustParse("100Mi"),
									},
								},
							},
						},
					},
				},
				mounter: mount.NewFakeMounter([]mount.MountPoint{{Path: tmpdir, Opts: []string{"rw", "pagesize=2M", "realtime"}}}),
				mountDetector: &testMountDetector{
					pageSize: &pageSize2Mi,
					isMnt:    true,
					err:      nil,
				},
			},
			shouldFail: false,
		},
		"Valid: already mounted": {
			path: tmpdir,
			ed: &emptyDir{
				medium: "HugePages",
				pod: &v1.Pod{
					Spec: v1.PodSpec{
						Containers: []v1.Container{
							{
								Resources: v1.ResourceRequirements{
									Requests: v1.ResourceList{
										v1.ResourceName("hugepages-2Mi"): resource.MustParse("100Mi"),
									},
								},
							},
						},
					},
				},
				mounter: mount.NewFakeMounter([]mount.MountPoint{{Path: tmpdir, Opts: []string{"rw", "pagesize=2M", "realtime"}}}),
				mountDetector: &testMountDetector{
					pageSize: nil,
					isMnt:    true,
					err:      nil,
				},
			},
			shouldFail: false,
		},
		"Invalid: mounter is nil": {
			path: tmpdir,
			ed: &emptyDir{
				medium: "HugePages-2Mi",
				pod: &v1.Pod{
					Spec: v1.PodSpec{
						Containers: []v1.Container{
							{
								Resources: v1.ResourceRequirements{
									Requests: v1.ResourceList{
										v1.ResourceName("hugepages-2Mi"): resource.MustParse("100Mi"),
									},
								},
							},
						},
					},
				},
				mounter: nil,
			},
			shouldFail: true,
		},
		"Invalid: GetMountMedium error": {
			path: tmpdir,
			ed: &emptyDir{
				medium: "HugePages-2Mi",
				pod: &v1.Pod{
					Spec: v1.PodSpec{
						Containers: []v1.Container{
							{
								Resources: v1.ResourceRequirements{
									Requests: v1.ResourceList{
										v1.ResourceName("hugepages-2Mi"): resource.MustParse("100Mi"),
									},
								},
							},
						},
					},
				},
				mounter: mount.NewFakeMounter([]mount.MountPoint{{Path: tmpdir, Opts: []string{"rw", "pagesize=2M", "realtime"}}}),
				mountDetector: &testMountDetector{
					pageSize: &pageSize2Mi,
					isMnt:    true,
					err:      fmt.Errorf("GetMountMedium error"),
				},
			},
			shouldFail: true,
		},
		"Invalid: medium and page size differ": {
			path: tmpdir,
			ed: &emptyDir{
				medium: "HugePages-1Gi",
				pod: &v1.Pod{
					Spec: v1.PodSpec{
						Containers: []v1.Container{
							{
								Resources: v1.ResourceRequirements{
									Requests: v1.ResourceList{
										v1.ResourceName("hugepages-1Gi"): resource.MustParse("2Gi"),
									},
								},
							},
						},
					},
				},
				mounter: mount.NewFakeMounter([]mount.MountPoint{{Path: tmpdir, Opts: []string{"rw", "pagesize=2M", "realtime"}}}),
				mountDetector: &testMountDetector{
					pageSize: &pageSize2Mi,
					isMnt:    true,
					err:      nil,
				},
			},
			shouldFail: true,
		},
		"Invalid medium": {
			path: tmpdir,
			ed: &emptyDir{
				medium: "HugePages-NN",
				pod: &v1.Pod{
					Spec: v1.PodSpec{
						Containers: []v1.Container{
							{
								Resources: v1.ResourceRequirements{
									Requests: v1.ResourceList{
										v1.ResourceName("hugepages-2Mi"): resource.MustParse("100Mi"),
									},
								},
							},
						},
					},
				},
				mounter: &mount.FakeMounter{},
				mountDetector: &testMountDetector{
					pageSize: &resource.Quantity{},
					isMnt:    false,
					err:      nil,
				},
			},
			shouldFail: true,
		},
		"Invalid: setupDir fails": {
			path: "",
			ed: &emptyDir{
				medium: v1.StorageMediumHugePages,
				pod: &v1.Pod{
					Spec: v1.PodSpec{
						Containers: []v1.Container{
							{
								Resources: v1.ResourceRequirements{
									Requests: v1.ResourceList{
										v1.ResourceName("hugepages-2Mi"): resource.MustParse("100Mi"),
									},
								},
							},
						},
					},
				},
				mounter: &mount.FakeMounter{},
			},
			shouldFail: true,
		},
	}

	for testCaseName, testCase := range testCases {
		t.Run(testCaseName, func(t *testing.T) {
			err := testCase.ed.setupHugepages(testCase.path)
			if testCase.shouldFail && err == nil {
				t.Errorf("%s: Unexpected success", testCaseName)
			} else if !testCase.shouldFail && err != nil {
				t.Errorf("%s: Unexpected error: %v", testCaseName, err)
			}
		})
	}
}