mountPrefix := "/var/lib/kubelet/plugins/kubernetes.io/iscsi/iface-default/" + devicePath
	lun := "-lun-0"
	device, prefix, err := extractDeviceAndPrefix(mountPrefix + lun)
	if err != nil || device != (devicePath+lun) || prefix != mountPrefix {
		t.Errorf("extractDeviceAndPrefix: expected %s and %s, got %v %s and %s", devicePath+lun, mountPrefix, err, device, prefix)
	}
}

func TestExtractIface(t *testing.T) {

			name: "pci-0000:41:00.0-fc-0x500a0981891b8dc5-lun-0",
		}
		f2 := &fakeFileInfo{
			name: "fc-0x5005076810213b32-lun-2",
		}
		f3 := &fakeFileInfo{
			name: "abc-0000:41:00.0-fc-0x5005076810213404-lun-0",
		}
		f4 := &fakeFileInfo{
			name: "pci-0000:41:00.0-fc-0x500a0981891b8dc5-lun-12",
		}
		f5 := &fakeFileInfo{
			name: "pci-0000:41:00.0-fc-0x500a0981891b8dc5-lun-1",
		}
		f6 := &fakeFileInfo{

	var lun string
	var wwids []string
	if fc.Lun != nil && len(fc.TargetWWNs) != 0 {
		lun = strconv.Itoa(int(*fc.Lun))
		return fc.TargetWWNs, lun, wwids, nil
	}
	if len(fc.WWIDs) != 0 {
		for _, wwid := range fc.WWIDs {
			wwids = append(wwids, strings.Replace(wwid, " ", "_", -1))
		}
		return fc.TargetWWNs, lun, wwids, nil
	}

	iqn := spec.PersistentVolume.Spec.PersistentVolumeSource.ISCSI.IQN
	if iqn != "iqn.2014-12.server:storage.target01" {
		t.Errorf("wrong iqn: %v", iqn)
	}
	lun := spec.PersistentVolume.Spec.PersistentVolumeSource.ISCSI.Lun
	if lun != 0 {
		t.Errorf("wrong lun: %v", lun)
	}
	iface := spec.PersistentVolume.Spec.PersistentVolumeSource.ISCSI.ISCSIInterface
	if iface != "default" {
		t.Errorf("wrong ISCSIInterface: %v", iface)
	}
}

	return ioutil.WriteFile(filename, data, perm)
}

// given a wwn and lun, find the device and associated devicemapper parent
func findDisk(wwn, lun string, io ioHandler, deviceUtil volumeutil.DeviceUtil) (string, string) {
	fcPathExp := "^(pci-.*-fc|fc)-0x" + wwn + "-lun-" + lun + "$"
	r := regexp.MustCompile(fcPathExp)
	devPath := byPath
	if dirs, err := io.ReadDir(devPath); err == nil {

		if strings.Contains(volumeInfo, "-lun-") {
			wwnLun := strings.Split(volumeInfo, "-lun-")
			if len(wwnLun) < 2 {
				t.Errorf("failed to retrieve TargetWWN and Lun. volumeInfo is invalid: %v", volumeInfo)
			}
			lun, _ := strconv.Atoi(wwnLun[1])
			lun32 := int32(lun)
			if wwnLun[0] != "50060e801049cfd1" || lun32 != 0 {
				t.Errorf("failed to retrieve TargetWWN and Lun")
			}
		} else {

					continue
				}
			}

			klog.V(5).Infof("AttachDisk: scanning SCSI host %d LUN %s", hostNumber, b.Lun)
			lunNumber, err := strconv.Atoi(b.Lun)
			if err != nil {
				return "", fmt.Errorf("AttachDisk: lun is not a number: %s\nError: %v", b.Lun, err)
			}

			// Scan the iSCSI bus for the LUN
			err = scanOneLun(hostNumber, lunNumber)
			if err != nil {
				return "", err
			}

	bkpPortal, iqn, err := extractPortalAndIqn(device)
	if err != nil {
		return volume.ReconstructedVolume{}, err
	}
	arr := strings.Split(device, "-lun-")
	if len(arr) < 2 {
		return volume.ReconstructedVolume{}, fmt.Errorf("failed to retrieve lun from globalPDPath: %v", globalPDPath)
	}
	lun, err := strconv.Atoi(arr[1])
	if err != nil {
		return volume.ReconstructedVolume{}, err
	}
	iface, _ := extractIface(globalPDPath)

	}
	return b
}

// WithLun sets the Lun field in the declarative configuration to the given value
// and returns the receiver, so that objects can be built by chaining "With" function invocations.
// If called multiple times, the Lun field is set to the value of the last call.
func (b *FCVolumeSourceApplyConfiguration) WithLun(value int32) *FCVolumeSourceApplyConfiguration {
	b.Lun = &value
	return b
}

	fc, readOnly, err := getVolumeSource(spec)
	if err != nil {
		return nil, err
	}
	var lun string
	var wwids []string
	if fc.Lun != nil && len(fc.TargetWWNs) != 0 {
		lun = strconv.Itoa(int(*fc.Lun))
	} else if len(fc.WWIDs) != 0 {
		for _, wwid := range fc.WWIDs {
			wwids = append(wwids, strings.Replace(wwid, " ", "_", -1))
		}
	} else {