fix linting (#4000)

.golangci.yml

@@ -45,3 +45,4 @@ linters:
 #     disabled-checks:
 #       - wrapperFunc
 #       - commentFormatting # https://github.com/go-critic/go-critic/issues/755
+

blockchain/v2/reactor.go

@@ -13,16 +13,14 @@ type timeCheck struct {
 }
 
 func schedulerHandle(event Event) (Event, error) {
-	switch event.(type) {
-	case timeCheck:
+	if _, ok := event.(timeCheck); ok {
 		fmt.Println("scheduler handle timeCheck")
 	}
 	return noOp, nil
 }
 
 func processorHandle(event Event) (Event, error) {
-	switch event.(type) {
-	case timeCheck:
+	if _, ok := event.(timeCheck); ok {
 		fmt.Println("processor handle timeCheck")
 	}
 	return noOp, nil

blockchain/v2/routine.go

@@ -42,6 +42,7 @@ func newRoutine(name string, handleFunc handleFunc, bufferSize int) *Routine {
 	}
 }
 
+// nolint: unused
 func (rt *Routine) setLogger(logger log.Logger) {
 	rt.logger = logger
 }

blockchain/v2/routine_test.go

@@ -15,8 +15,7 @@ type eventA struct {
 var done = fmt.Errorf("done")
 
 func simpleHandler(event Event) (Event, error) {
-	switch event.(type) {
-	case eventA:
+	if _, ok := event.(eventA); ok {
 		return noOp, done
 	}
 	return noOp, nil