},
			}
			ver, err := GetKubeletVersion(fexec)
			switch {
			case err != nil && tc.valid:
				t.Errorf("GetKubeletVersion: unexpected error for %q. Error: %v", tc.output, err)
			case err == nil && !tc.valid:
				t.Errorf("GetKubeletVersion: error expected for key %q, but result is %q", tc.output, ver)
			case ver != nil && ver.String() != tc.expected:

import (
	"regexp"
	"strings"

	"github.com/pkg/errors"

	"k8s.io/apimachinery/pkg/util/version"
	utilsexec "k8s.io/utils/exec"
)

// GetKubeletVersion is helper function that returns version of kubelet available in $PATH
func GetKubeletVersion(execer utilsexec.Interface) (*version.Version, error) {
	kubeletVersionRegex := regexp.MustCompile(`^\s*Kubernetes v((0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)([-\w.+]*)?)\s*$`)

func (kubever KubeletVersionCheck) Check() (warnings, errorList []error) {
	klog.V(1).Infoln("validating kubelet version")
	kubeletVersion, err := GetKubeletVersion(kubever.exec)
	if err != nil {
		return nil, []error{errors.Wrap(err, "couldn't get kubelet version")}
	}
	if kubever.minKubeletVersion == nil {
		kubever.minKubeletVersion = kubeadmconstants.MinimumKubeletVersion