Address various linter (staticcheck, modernize, etc.) comments.

pkg/controller/controller.go

@@ -145,31 +145,31 @@ func NewResizeController(
 	return ctrl
 }
 
-func (ctrl *resizeController) addPVC(obj interface{}) {
+func (ctrl *resizeController) addPVC(obj any) {
 	objKey, err := util.GetObjectKey(obj)
 	if err != nil {
 		return
 	}
 	ctrl.claimQueue.Add(objKey)
 }
 
-func (ctrl *resizeController) addPod(obj interface{}) {
+func (ctrl *resizeController) addPod(obj any) {
 	pod := parsePod(obj)
 	if pod == nil {
 		return
 	}
 	ctrl.usedPVCs.addPod(pod)
 }
 
-func (ctrl *resizeController) deletePod(obj interface{}) {
+func (ctrl *resizeController) deletePod(obj any) {
 	pod := parsePod(obj)
 	if pod == nil {
 		return
 	}
 	ctrl.usedPVCs.removePod(pod)
 }
 
-func (ctrl *resizeController) updatePod(oldObj, newObj interface{}) {
+func (ctrl *resizeController) updatePod(oldObj, newObj any) {
 	pod := parsePod(newObj)
 	if pod == nil {
 		return
@@ -182,7 +182,7 @@ func (ctrl *resizeController) updatePod(oldObj, newObj interface{}) {
 	}
 }
 
-func (ctrl *resizeController) updatePVC(oldObj, newObj interface{}) {
+func (ctrl *resizeController) updatePVC(oldObj, newObj any) {
 	oldPVC, ok := oldObj.(*v1.PersistentVolumeClaim)
 	if !ok || oldPVC == nil {
 		return
@@ -261,7 +261,7 @@ func (ctrl *resizeController) updatePVC(oldObj, newObj interface{}) {
 	}
 }
 
-func (ctrl *resizeController) deletePVC(obj interface{}) {
+func (ctrl *resizeController) deletePVC(obj any) {
 	objKey, err := util.GetObjectKey(obj)
 	if err != nil {
 		return
@@ -291,7 +291,7 @@ func (ctrl *resizeController) Run(workers int, ctx context.Context) {
 		go ctrl.slowSet.Run(stopCh)
 	}
 
-	for i := 0; i < workers; i++ {
+	for range workers {
 		go wait.Until(ctrl.syncPVCs, 0, stopCh)
 	}
 
@@ -566,7 +566,7 @@ func (ctrl *resizeController) markPVCResizeInProgress(pvc *v1.PersistentVolumeCl
 
 	updatedPVC, err := util.PatchClaim(ctrl.kubeClient, pvc, newPVC, true /* addResourceVersionCheck */)
 	if err != nil {
-		return updatedPVC, fmt.Errorf("Mark PVC %q as resize as in progress failed: %v", klog.KObj(pvc), err)
+		return updatedPVC, fmt.Errorf("mark PVC %q as resize as in progress failed: %v", klog.KObj(pvc), err)
 	}
 	err = ctrl.claims.Update(updatedPVC)
 	if err != nil {
@@ -584,7 +584,7 @@ func (ctrl *resizeController) markPVCResizeFinished(
 
 	updatedPVC, err := util.PatchClaim(ctrl.kubeClient, pvc, newPVC, true /* addResourceVersionCheck */)
 	if err != nil {
-		return fmt.Errorf("Mark PVC %q as resize finished failed: %w", klog.KObj(pvc), err)
+		return fmt.Errorf("mark PVC %q as resize finished failed: %w", klog.KObj(pvc), err)
 	}
 
 	err = ctrl.claims.Update(updatedPVC)
@@ -636,7 +636,7 @@ func (ctrl *resizeController) updatePVCapacity(
 	return updatedPV, nil
 }
 
-func parsePod(obj interface{}) *v1.Pod {
+func parsePod(obj any) *v1.Pod {
 	if obj == nil {
 		return nil
 	}

pkg/csi/mock_client.go

@@ -98,7 +98,7 @@ func (c *MockClient) Expand(
 		additionalInfoVal := additionalInfo.(connection.AdditionalInfo)
 		migrated := additionalInfoVal.Migrated
 		if migrated != "true" {
-			err := fmt.Errorf("Expected value of migrated label: true, Actual value: %s", migrated)
+			err := fmt.Errorf("migrated label expected value: true, actual value: %s", migrated)
 			return requestBytes, c.supportsNodeResize, err
 		}
 	}

pkg/modifier/csi_modifier_test.go

@@ -1,7 +1,6 @@
 package modifier
 
 import (
-	"errors"
 	"testing"
 
 	"github.com/kubernetes-csi/external-resizer/pkg/csi"
@@ -10,10 +9,6 @@ import (
 	"k8s.io/client-go/kubernetes/fake"
 )
 
-var (
-	controllerServiceNotSupportErr = errors.New("CSI driver does not support controller service")
-)
-
 func TestNewModifier(t *testing.T) {
 	for i, c := range []struct {
 		SupportsControllerModify bool

pkg/modifycontroller/controller.go

@@ -140,15 +140,15 @@ func (ctrl *modifyController) initUncertainPVCs() error {
 	return nil
 }
 
-func (ctrl *modifyController) addPVC(obj interface{}) {
+func (ctrl *modifyController) addPVC(obj any) {
 	objKey, err := util.GetObjectKey(obj)
 	if err != nil {
 		return
 	}
 	ctrl.claimQueue.Add(objKey)
 }
 
-func (ctrl *modifyController) updatePVC(oldObj, newObj interface{}) {
+func (ctrl *modifyController) updatePVC(oldObj, newObj any) {
 	oldPVC, ok := oldObj.(*v1.PersistentVolumeClaim)
 	if !ok || oldPVC == nil {
 		return
@@ -178,7 +178,7 @@ func (ctrl *modifyController) updatePVC(oldObj, newObj interface{}) {
 	}
 }
 
-func (ctrl *modifyController) deletePVC(obj interface{}) {
+func (ctrl *modifyController) deletePVC(obj any) {
 	objKey, err := util.GetObjectKey(obj)
 	if err != nil {
 		return
@@ -220,7 +220,7 @@ func (ctrl *modifyController) Run(
 	// Starts go-routine that deletes expired slowSet entries.
 	go ctrl.slowSet.Run(stopCh)
 
-	for i := 0; i < workers; i++ {
+	for range workers {
 		go wait.Until(ctrl.sync, 0, stopCh)
 	}
 
@@ -265,7 +265,7 @@ func (ctrl *modifyController) syncPVC(key string) error {
 
 	pv, err := ctrl.pvLister.Get(pvc.Spec.VolumeName)
 	if err != nil {
-		return fmt.Errorf("Get PV %q of pvc %q in PVInformer cache failed: %v", pvc.Spec.VolumeName, klog.KObj(pvc), err)
+		return fmt.Errorf("get pv %q of pvc %q in PVInformer cache failed: %v", pvc.Spec.VolumeName, klog.KObj(pvc), err)
 	}
 
 	// Only trigger modify volume if the following conditions are met

pkg/modifycontroller/modify_status.go

@@ -48,7 +48,7 @@ func (ctrl *modifyController) markControllerModifyVolumeStatus(
 	case v1.PersistentVolumeClaimModifyVolumeInProgress:
 		conditionMessage = "ModifyVolume operation in progress."
 	case v1.PersistentVolumeClaimModifyVolumeInfeasible:
-		conditionMessage = "ModifyVolume failed with error" + err.Error() + ". Waiting for retry."
+		conditionMessage = "ModifyVolume failed with error: " + err.Error() + ". Waiting for retry."
 	}
 	pvcCondition.Message = conditionMessage
 	// Do not change conditions for pending modifications and keep existing conditions

pkg/modifycontroller/modify_status_test.go

@@ -2,7 +2,7 @@ package modifycontroller
 
 import (
 	"context"
-	"reflect"
+	"errors"
 	"testing"
 	"time"
 
@@ -37,7 +37,6 @@ var (
 	targetVac              = "target-vac"
 	testDriverName         = "mock"
 	infeasibleErr          = status.Errorf(codes.InvalidArgument, "Parameters in VolumeAttributesClass is invalid")
-	finalErr               = status.Errorf(codes.Internal, "Final error")
 	pvcConditionInProgress = v1.PersistentVolumeClaimCondition{
 		Type:    v1.PersistentVolumeClaimVolumeModifyingVolume,
 		Status:  v1.ConditionTrue,
@@ -47,7 +46,7 @@ var (
 	pvcConditionInfeasible = v1.PersistentVolumeClaimCondition{
 		Type:    v1.PersistentVolumeClaimVolumeModifyingVolume,
 		Status:  v1.ConditionTrue,
-		Message: "ModifyVolume failed with errorrpc error: code = InvalidArgument desc = Parameters in VolumeAttributesClass is invalid. Waiting for retry.",
+		Message: "ModifyVolume failed with error: rpc error: code = InvalidArgument desc = Parameters in VolumeAttributesClass is invalid. Waiting for retry.",
 	}
 
 	pvcConditionError = v1.PersistentVolumeClaimCondition{
@@ -83,7 +82,7 @@ func TestMarkControllerModifyVolumeStatus(t *testing.T) {
 			pvc:                basePVC.Get(),
 			expectedPVC:        basePVC.WithModifyVolumeStatus(v1.PersistentVolumeClaimModifyVolumeInfeasible).Get(),
 			expectedConditions: []v1.PersistentVolumeClaimCondition{pvcConditionInfeasible},
-			expectedErr:        infeasibleErr,
+			expectedErr:        nil,
 			testFunc: func(pvc *v1.PersistentVolumeClaim, ctrl *modifyController) (*v1.PersistentVolumeClaim, error) {
 				return ctrl.markControllerModifyVolumeStatus(pvc, v1.PersistentVolumeClaimModifyVolumeInfeasible, infeasibleErr)
 			},
@@ -126,14 +125,14 @@ func TestMarkControllerModifyVolumeStatus(t *testing.T) {
 			ctrlInstance, _ := controller.(*modifyController)
 
 			pvc, err = tc.testFunc(pvc, ctrlInstance)
-			if err != nil && !reflect.DeepEqual(tc.expectedErr, err) {
-				t.Errorf("Expected error to be %v but got %v", tc.expectedErr, err)
+			if !errors.Is(err, tc.expectedErr) {
+				t.Errorf("expected error: %v, got: %v", tc.expectedErr, err)
 			}
 
 			realStatus := pvc.Status.ModifyVolumeStatus.Status
 			expectedStatus := tc.expectedPVC.Status.ModifyVolumeStatus.Status
-			if !reflect.DeepEqual(realStatus, expectedStatus) {
-				t.Errorf("expected modify volume status %+v got %+v", expectedStatus, realStatus)
+			if diff := cmp.Diff(expectedStatus, realStatus); diff != "" {
+				t.Errorf("unexpected modify volume status (-want +got):\n%s", diff)
 			}
 
 			realConditions := pvc.Status.Conditions
@@ -167,8 +166,6 @@ func TestUpdateConditionBasedOnError(t *testing.T) {
 			client := csi.NewMockClient("foo", true, true, true, true, true, false)
 			driverName, _ := client.GetDriverName(context.TODO())
 
-			pvc := test.pvc
-
 			var initialObjects []runtime.Object
 			initialObjects = append(initialObjects, test.pvc)
 
@@ -185,9 +182,9 @@ func TestUpdateConditionBasedOnError(t *testing.T) {
 
 			ctrlInstance, _ := controller.(*modifyController)
 
-			pvc, err = ctrlInstance.updateConditionBasedOnError(tc.pvc, err)
-			if err != nil && !reflect.DeepEqual(tc.expectedErr, err) {
-				t.Errorf("Expected error to be %v but got %v", tc.expectedErr, err)
+			pvc, err := ctrlInstance.updateConditionBasedOnError(tc.pvc, err)
+			if !errors.Is(err, tc.expectedErr) {
+				t.Errorf("expected error: %v, got: %v", tc.expectedErr, err)
 			}
 
 			if !testutil.CompareConditions(pvc.Status.Conditions, tc.expectedConditions) {
@@ -254,20 +251,20 @@ func TestMarkControllerModifyVolumeCompleted(t *testing.T) {
 			ctrlInstance, _ := controller.(*modifyController)
 
 			actualPVC, pv, err := ctrlInstance.markControllerModifyVolumeCompleted(tc.pvc, tc.pv)
-			if err != nil && !reflect.DeepEqual(tc.expectedErr, err) {
-				t.Errorf("Expected error to be %v but got %v", tc.expectedErr, err)
+			if !errors.Is(err, tc.expectedErr) {
+				t.Errorf("expected error: %v, got: %v", tc.expectedErr, err)
 			}
 
 			if len(actualPVC.Status.Conditions) == 0 {
 				actualPVC.Status.Conditions = []v1.PersistentVolumeClaimCondition{}
 			}
 
 			if diff := cmp.Diff(tc.expectedPVC, actualPVC); diff != "" {
-				t.Errorf("expected pvc %+v got %+v, diff is: %v", tc.expectedPVC, actualPVC, diff)
+				t.Errorf("unexpected pvc (-want +got):\n%s", diff)
 			}
 
 			if diff := cmp.Diff(tc.expectedPV, pv); diff != "" {
-				t.Errorf("expected pvc %+v got %+v, diff is: %v", tc.expectedPV, pv, diff)
+				t.Errorf("unexpected pv (-want +got):\n%s", diff)
 			}
 		})
 	}

pkg/resizer/csi_resizer.go

@@ -37,8 +37,8 @@ import (
 )
 
 var (
-	controllerServiceNotSupportErr = errors.New("CSI driver does not support controller service")
-	resizeNotSupportErr            = errors.New("CSI driver neither supports controller resize nor node resize")
+	errControllerServiceNotSupport = errors.New("CSI driver does not support controller service")
+	errResizeNotSupport            = errors.New("CSI driver neither supports controller resize nor node resize")
 )
 
 func NewResizerFromClient(
@@ -53,7 +53,7 @@ func NewResizerFromClient(
 	}
 
 	if !supportControllerService {
-		return nil, controllerServiceNotSupportErr
+		return nil, errControllerServiceNotSupport
 	}
 
 	supportControllerResize, err := supportsControllerResize(csiClient, timeout)
@@ -70,7 +70,7 @@ func NewResizerFromClient(
 			klog.InfoS("The CSI driver supports node resize only, using trivial resizer to handle resize requests")
 			return newTrivialResizer(driverName), nil
 		}
-		return nil, resizeNotSupportErr
+		return nil, errResizeNotSupport
 	}
 
 	_, err = supportsControllerSingleNodeMultiWriter(csiClient, timeout)

pkg/resizer/csi_resizer_test.go

@@ -42,7 +42,7 @@ func TestNewResizer(t *testing.T) {
 			SupportsPluginControllerService:         false,
 			SupportsControllerSingleNodeMultiWriter: true,
 
-			Error: controllerServiceNotSupportErr,
+			Error: errControllerServiceNotSupport,
 		},
 		// Controller modify not supported.
 		{
@@ -69,7 +69,7 @@ func TestNewResizer(t *testing.T) {
 			SupportsPluginControllerService:         true,
 			SupportsControllerSingleNodeMultiWriter: true,
 
-			Error: resizeNotSupportErr,
+			Error: errResizeNotSupport,
 		},
 	} {
 		client := csi.NewMockClient("mock", c.SupportsNodeResize, c.SupportsControllerResize, false, c.SupportsPluginControllerService, c.SupportsControllerSingleNodeMultiWriter, false)

pkg/util/util.go

@@ -139,7 +139,7 @@ func GetPVCPatchData(oldPVC, newPVC *v1.PersistentVolumeClaim, addResourceVersio
 }
 
 func addResourceVersion(patchBytes []byte, resourceVersion string) ([]byte, error) {
-	var patchMap map[string]interface{}
+	var patchMap map[string]any
 	err := json.Unmarshal(patchBytes, &patchMap)
 	if err != nil {
 		return nil, fmt.Errorf("error unmarshalling patch with %v", err)
@@ -157,7 +157,7 @@ func addResourceVersion(patchBytes []byte, resourceVersion string) ([]byte, erro
 	return versionBytes, nil
 }
 
-func GetPatchData(oldObj, newObj interface{}) ([]byte, error) {
+func GetPatchData(oldObj, newObj any) ([]byte, error) {
 	oldData, err := json.Marshal(oldObj)
 	if err != nil {
 		return nil, fmt.Errorf("marshal old object failed: %v", err)
@@ -195,7 +195,7 @@ func SanitizeName(name string) string {
 	return name
 }
 
-func GetObjectKey(obj interface{}) (string, error) {
+func GetObjectKey(obj any) (string, error) {
 	if unknown, ok := obj.(cache.DeletedFinalStateUnknown); ok && unknown.Obj != nil {
 		obj = unknown.Obj
 	}

pkg/util/util_test.go

@@ -60,13 +60,13 @@ func TestGetPVCPatchData(t *testing.T) {
 			t.Errorf("Case %d: Get patch data failed: %v", i, err)
 		}
 
-		var patchMap map[string]interface{}
+		var patchMap map[string]any
 		err = json.Unmarshal(patchBytes, &patchMap)
 		if err != nil {
 			t.Errorf("Case %d: unmarshalling json patch failed: %v", i, err)
 		}
 
-		metadata, exist := patchMap["metadata"].(map[string]interface{})
+		metadata, exist := patchMap["metadata"].(map[string]any)
 		if !exist {
 			t.Errorf("Case %d: ResourceVersion should exist in patch data", i)
 		}