Add gosimple linter (#9590)

.golangci.yml

@@ -73,6 +73,7 @@ linters:
     - structcheck
     - unconvert
     - gofmt
+    - gosimple
     # Stretch Goal
     #- maligned
   fast: false

client/agent_endpoint.go

@@ -135,10 +135,7 @@ func (a *Agent) monitor(conn io.ReadWriteCloser) {
 			cancel()
 			return
 		}
-		select {
-		case <-ctx.Done():
-			return
-		}
+		<-ctx.Done()
 	}()
 
 	logCh := monitor.Start()

client/allocdir/fs_linux.go

@@ -55,8 +55,7 @@ func createSecretDir(dir string) error {
 			return nil
 		}
 
-		var flags uintptr
-		flags = syscall.MS_NOEXEC
+		flags := uintptr(syscall.MS_NOEXEC)
 		options := fmt.Sprintf("size=%dm", secretDirTmpfsSize)
 		if err := syscall.Mount("tmpfs", dir, "tmpfs", flags, options); err != nil {
 			return os.NewSyscallError("mount", err)

client/allocrunner/health_hook.go

@@ -215,7 +215,7 @@ func (h *allocHealthWatcherHook) watchHealth(ctx context.Context, deadline time.
 		// Allocation has stopped so no need to set health
 		return
 
-	case <-time.After(deadline.Sub(time.Now())):
+	case <-time.After(time.Until(deadline)):
 		// Time is up! Fallthrough to set unhealthy.
 		h.logger.Trace("deadline reached; setting unhealthy", "deadline", deadline)
 

client/allocrunner/taskrunner/plugin_supervisor_hook.go

@@ -161,7 +161,7 @@ func (h *csiPluginSupervisorHook) Poststart(_ context.Context, _ *interfaces.Tas
 // Deeper fingerprinting of the plugin is implemented by the csimanager.
 func (h *csiPluginSupervisorHook) ensureSupervisorLoop(ctx context.Context) {
 	h.runningLock.Lock()
-	if h.running == true {
+	if h.running {
 		h.runningLock.Unlock()
 		return
 	}

client/client.go

@@ -1613,7 +1613,7 @@ func (c *Client) getHeartbeatRetryIntv(err error) time.Duration {
 	}
 
 	// Determine how much time we have left to heartbeat
-	left := last.Add(ttl).Sub(time.Now())
+	left := time.Until(last.Add(ttl))
 
 	// Logic for retrying is:
 	// * Do not retry faster than once a second

client/devicemanager/instance.go

@@ -406,8 +406,6 @@ func (i *instanceManager) handleFingerprintError() {
 
 	// Cancel the context so we cleanup all goroutines
 	i.cancel()
-
-	return
 }
 
 // handleFingerprint stores the new devices and triggers the fingerprint output

client/dynamicplugins/registry.go

@@ -373,9 +373,7 @@ func (p *pluginEventBroadcaster) run() {
 		case msg := <-p.publishCh:
 			p.subscriptionsLock.RLock()
 			for msgCh := range p.subscriptions {
-				select {
-				case msgCh <- msg:
-				}
+				msgCh <- msg
 			}
 			p.subscriptionsLock.RUnlock()
 		}

client/enterprise_client_oss.go

@@ -12,6 +12,4 @@ func newEnterpriseClient(logger hclog.Logger) *EnterpriseClient {
 }
 
 // SetFeatures is used for enterprise builds to configure enterprise features
-func (ec *EnterpriseClient) SetFeatures(features uint64) {
-	return
-}
+func (ec *EnterpriseClient) SetFeatures(features uint64) {}

client/fingerprint/structs.go

@@ -30,7 +30,7 @@ type FingerprintResponse struct {
 func (f *FingerprintResponse) AddAttribute(name, value string) {
 	// initialize Attributes if it has not been already
 	if f.Attributes == nil {
-		f.Attributes = make(map[string]string, 0)
+		f.Attributes = make(map[string]string)
 	}
 
 	f.Attributes[name] = value
@@ -41,7 +41,7 @@ func (f *FingerprintResponse) AddAttribute(name, value string) {
 func (f *FingerprintResponse) RemoveAttribute(name string) {
 	// initialize Attributes if it has not been already
 	if f.Attributes == nil {
-		f.Attributes = make(map[string]string, 0)
+		f.Attributes = make(map[string]string)
 	}
 
 	f.Attributes[name] = ""
@@ -51,7 +51,7 @@ func (f *FingerprintResponse) RemoveAttribute(name string) {
 func (f *FingerprintResponse) AddLink(name, value string) {
 	// initialize Links if it has not been already
 	if f.Links == nil {
-		f.Links = make(map[string]string, 0)
+		f.Links = make(map[string]string)
 	}
 
 	f.Links[name] = value
@@ -62,7 +62,7 @@ func (f *FingerprintResponse) AddLink(name, value string) {
 func (f *FingerprintResponse) RemoveLink(name string) {
 	// initialize Links if it has not been already
 	if f.Links == nil {
-		f.Links = make(map[string]string, 0)
+		f.Links = make(map[string]string)
 	}
 
 	f.Links[name] = ""

client/logmon/logging/rotator.go

@@ -295,7 +295,7 @@ func (f *FileRotator) purgeOldFiles() {
 
 			// Sorting the file indexes so that we can purge the older files and keep
 			// only the number of files as configured by the user
-			sort.Sort(sort.IntSlice(fIndexes))
+			sort.Ints(fIndexes)
 			toDelete := fIndexes[0 : len(fIndexes)-f.MaxFiles]
 			for _, fIndex := range toDelete {
 				fname := filepath.Join(f.path, fmt.Sprintf("%s.%d", f.baseFileName, fIndex))

client/logmon/logmon.go

@@ -253,7 +253,6 @@ func (l *logRotatorWrapper) start(openFn func() (io.ReadCloser, error)) {
 			reader.Close()
 		}
 	}()
-	return
 }
 
 // Close closes the rotator and the process writer to ensure that the Wait

client/pluginmanager/group.go

@@ -65,14 +65,12 @@ func (m *PluginGroup) WaitForFirstFingerprint(ctx context.Context) (<-chan struc
 		go func() {
 			defer wg.Done()
 			logger.Debug("waiting on plugin manager initial fingerprint")
+			<-manager.WaitForFirstFingerprint(ctx)
 			select {
-			case <-manager.WaitForFirstFingerprint(ctx):
-				select {
-				case <-ctx.Done():
-					logger.Warn("timeout waiting for plugin manager to be ready")
-				default:
-					logger.Debug("finished plugin manager initial fingerprint")
-				}
+			case <-ctx.Done():
+				logger.Warn("timeout waiting for plugin manager to be ready")
+			default:
+				logger.Debug("finished plugin manager initial fingerprint")
 			}
 		}()
 	}

client/rpc.go

@@ -114,7 +114,7 @@ TRY:
 	case <-time.After(lib.RandomStagger(c.config.RPCHoldTimeout / structs.JitterFraction)):
 		// If we are going to retry a blocking query we need to update the time to block so it finishes by our deadline.
 		if info, ok := args.(structs.RPCInfo); ok && info.TimeToBlock() > 0 {
-			newBlockTime := deadline.Sub(time.Now())
+			newBlockTime := time.Until(deadline)
 			// We can get below 0 here on slow computers because we slept for jitter so at least try to get an immediate response
 			if newBlockTime < 0 {
 				newBlockTime = 0

client/state/08types.go

@@ -108,10 +108,7 @@ func (t *taskRunnerState08) Upgrade(allocID, taskName string) (*state.LocalState
 
 	// The docker driver prefixed the handle with 'DOCKER:'
 	// Strip so that it can be unmarshalled
-	data := t.HandleID
-	if strings.HasPrefix(data, "DOCKER:") {
-		data = data[7:]
-	}
+	data := strings.TrimPrefix(t.HandleID, "DOCKER:")
 
 	// The pre09 driver handle ID is given to the driver. It is unmarshalled
 	// here to check for errors

client/structs/structs.go

@@ -331,7 +331,7 @@ type HealthCheckIntervalResponse struct {
 func (h *HealthCheckResponse) AddDriverInfo(name string, driverInfo *structs.DriverInfo) {
 	// initialize Drivers if it has not been already
 	if h.Drivers == nil {
-		h.Drivers = make(map[string]*structs.DriverInfo, 0)
+		h.Drivers = make(map[string]*structs.DriverInfo)
 	}
 
 	h.Drivers[name] = driverInfo

client/vaultclient/vaultclient.go

@@ -479,7 +479,7 @@ func (c *vaultClient) run() {
 				// Compute the duration after which the item
 				// needs renewal and set the renewalCh to fire
 				// at that time.
-				renewalDuration := renewalTime.Sub(time.Now())
+				renewalDuration := time.Until(renewalTime)
 				renewalCh = time.After(renewalDuration)
 			} else {
 				// If the renewals of multiple items are too

command/acl_policy_list.go

@@ -111,7 +111,7 @@ func formatPolicies(policies []*api.ACLPolicyListStub) string {
 	}
 
 	output := make([]string, 0, len(policies)+1)
-	output = append(output, fmt.Sprintf("Name|Description"))
+	output = append(output, "Name|Description")
 	for _, p := range policies {
 		output = append(output, fmt.Sprintf("%s|%s", p.Name, p.Description))
 	}

command/acl_token_list.go

@@ -108,7 +108,7 @@ func formatTokens(tokens []*api.ACLTokenListStub) string {
 	}
 
 	output := make([]string, 0, len(tokens)+1)
-	output = append(output, fmt.Sprintf("Name|Type|Global|Accessor ID"))
+	output = append(output, "Name|Type|Global|Accessor ID")
 	for _, p := range tokens {
 		output = append(output, fmt.Sprintf("%s|%s|%t|%s", p.Name, p.Type, p.Global, p.AccessorID))
 	}

command/agent/command.go

@@ -882,7 +882,7 @@ func (c *Command) handleReload() {
 	c.Ui.Output("Reloading configuration...")
 	newConf := c.readConfig()
 	if newConf == nil {
-		c.Ui.Error(fmt.Sprintf("Failed to reload configs"))
+		c.Ui.Error("Failed to reload configs")
 		return
 	}
 

command/agent/http.go

@@ -400,7 +400,6 @@ func (s *HTTPServer) handleUI(h http.Handler) http.Handler {
 		header := w.Header()
 		header.Add("Content-Security-Policy", "default-src 'none'; connect-src *; img-src 'self' data:; script-src 'self'; style-src 'self' 'unsafe-inline'; form-action 'none'; frame-ancestors 'none'")
 		h.ServeHTTP(w, req)
-		return
 	})
 }
 
@@ -448,7 +447,7 @@ func (s *HTTPServer) wrap(handler func(resp http.ResponseWriter, req *http.Reque
 		reqURL := req.URL.String()
 		start := time.Now()
 		defer func() {
-			s.logger.Debug("request complete", "method", req.Method, "path", reqURL, "duration", time.Now().Sub(start))
+			s.logger.Debug("request complete", "method", req.Method, "path", reqURL, "duration", time.Since(start))
 		}()
 		obj, err := s.auditHandler(handler)(resp, req)
 
@@ -524,7 +523,7 @@ func (s *HTTPServer) wrapNonJSON(handler func(resp http.ResponseWriter, req *htt
 		reqURL := req.URL.String()
 		start := time.Now()
 		defer func() {
-			s.logger.Debug("request complete", "method", req.Method, "path", reqURL, "duration", time.Now().Sub(start))
+			s.logger.Debug("request complete", "method", req.Method, "path", reqURL, "duration", time.Since(start))
 		}()
 		obj, err := s.auditNonJSONHandler(handler)(resp, req)
 
@@ -595,7 +594,7 @@ func setMeta(resp http.ResponseWriter, m *structs.QueryMeta) {
 // setHeaders is used to set canonical response header fields
 func setHeaders(resp http.ResponseWriter, headers map[string]string) {
 	for field, value := range headers {
-		resp.Header().Set(http.CanonicalHeaderKey(field), value)
+		resp.Header().Set(field, value)
 	}
 }
 

command/agent_info.go

@@ -79,7 +79,7 @@ func (c *AgentInfoCommand) Run(args []string) int {
 
 	for _, key := range statsKeys {
 		c.Ui.Output(key)
-		statsData, _ := info.Stats[key]
+		statsData := info.Stats[key]
 		statsDataKeys := make([]string, len(statsData))
 		i := 0
 		for key := range statsData {

command/agent_monitor.go

@@ -97,7 +97,7 @@ func (c *MonitorCommand) Run(args []string) int {
 
 	// Query the node info and lookup prefix
 	if len(nodeID) == 1 {
-		c.Ui.Error(fmt.Sprintf("Node identifier must contain at least two characters."))
+		c.Ui.Error("Node identifier must contain at least two characters.")
 		return 1
 	}
 

command/alloc_exec.go

@@ -168,7 +168,7 @@ func (l *AllocExecCommand) Run(args []string) int {
 
 	// Query the allocation info
 	if len(allocID) == 1 {
-		l.Ui.Error(fmt.Sprintf("Alloc ID must contain at least two characters."))
+		l.Ui.Error("Alloc ID must contain at least two characters.")
 		return 1
 	}
 

command/alloc_fs.go

@@ -178,7 +178,7 @@ func (f *AllocFSCommand) Run(args []string) int {
 	}
 	// Query the allocation info
 	if len(allocID) == 1 {
-		f.Ui.Error(fmt.Sprintf("Alloc ID must contain at least two characters."))
+		f.Ui.Error("Alloc ID must contain at least two characters.")
 		return 1
 	}
 

command/alloc_logs.go

@@ -158,7 +158,7 @@ func (l *AllocLogsCommand) Run(args []string) int {
 	}
 	// Query the allocation info
 	if len(allocID) == 1 {
-		l.Ui.Error(fmt.Sprintf("Alloc ID must contain at least two characters."))
+		l.Ui.Error("Alloc ID must contain at least two characters.")
 		return 1
 	}
 

command/alloc_restart.go

@@ -68,7 +68,7 @@ func (c *AllocRestartCommand) Run(args []string) int {
 
 	// Query the allocation info
 	if len(allocID) == 1 {
-		c.Ui.Error(fmt.Sprintf("Alloc ID must contain at least two characters."))
+		c.Ui.Error("Alloc ID must contain at least two characters.")
 		return 1
 	}
 

command/alloc_signal.go

@@ -73,7 +73,7 @@ func (c *AllocSignalCommand) Run(args []string) int {
 
 	// Query the allocation info
 	if len(allocID) == 1 {
-		c.Ui.Error(fmt.Sprintf("Alloc ID must contain at least two characters."))
+		c.Ui.Error("Alloc ID must contain at least two characters.")
 		return 1
 	}
 

command/alloc_status.go

@@ -149,7 +149,7 @@ func (c *AllocStatusCommand) Run(args []string) int {
 
 	// Query the allocation info
 	if len(allocID) == 1 {
-		c.Ui.Error(fmt.Sprintf("Identifier must contain at least two characters."))
+		c.Ui.Error("Identifier must contain at least two characters.")
 		return 1
 	}
 

command/alloc_stop.go

@@ -76,7 +76,7 @@ func (c *AllocStopCommand) Run(args []string) int {
 
 	// Query the allocation info
 	if len(allocID) == 1 {
-		c.Ui.Error(fmt.Sprintf("Alloc ID must contain at least two characters."))
+		c.Ui.Error("Alloc ID must contain at least two characters.")
 		return 1
 	}
 

command/eval_status.go

@@ -139,7 +139,7 @@ func (c *EvalStatusCommand) Run(args []string) int {
 
 	// Query the allocation info
 	if len(evalID) == 1 {
-		c.Ui.Error(fmt.Sprintf("Identifier must contain at least two characters."))
+		c.Ui.Error("Identifier must contain at least two characters.")
 		return 1
 	}
 

command/job_plan.go

@@ -255,7 +255,7 @@ func (c *JobPlanCommand) addPreemptions(resp *api.JobPlanResponse) {
 	c.Ui.Output(c.Colorize().Color("[bold][yellow]Preemptions:\n[reset]"))
 	if len(resp.Annotations.PreemptedAllocs) < preemptionDisplayThreshold {
 		var allocs []string
-		allocs = append(allocs, fmt.Sprintf("Alloc ID|Job ID|Task Group"))
+		allocs = append(allocs, "Alloc ID|Job ID|Task Group")
 		for _, alloc := range resp.Annotations.PreemptedAllocs {
 			allocs = append(allocs, fmt.Sprintf("%s|%s|%s", alloc.ID, alloc.JobID, alloc.TaskGroup))
 		}
@@ -284,7 +284,7 @@ func (c *JobPlanCommand) addPreemptions(resp *api.JobPlanResponse) {
 	// Show counts grouped by job ID if its less than a threshold
 	var output []string
 	if numJobs < preemptionDisplayThreshold {
-		output = append(output, fmt.Sprintf("Job ID|Namespace|Job Type|Preemptions"))
+		output = append(output, "Job ID|Namespace|Job Type|Preemptions")
 		for jobType, jobCounts := range allocDetails {
 			for jobId, count := range jobCounts {
 				output = append(output, fmt.Sprintf("%s|%s|%s|%d", jobId.id, jobId.namespace, jobType, count))
@@ -292,7 +292,7 @@ func (c *JobPlanCommand) addPreemptions(resp *api.JobPlanResponse) {
 		}
 	} else {
 		// Show counts grouped by job type
-		output = append(output, fmt.Sprintf("Job Type|Preemptions"))
+		output = append(output, "Job Type|Preemptions")
 		for jobType, jobCounts := range allocDetails {
 			total := 0
 			for _, count := range jobCounts {

command/job_status.go

@@ -188,7 +188,7 @@ func (c *JobStatusCommand) Run(args []string) int {
 
 	if periodic && !parameterized {
 		if *job.Stop {
-			basic = append(basic, fmt.Sprintf("Next Periodic Launch|none (job stopped)"))
+			basic = append(basic, "Next Periodic Launch|none (job stopped)")
 		} else {
 			location, err := job.Periodic.GetLocation()
 			if err == nil {

command/node_config.go

@@ -97,7 +97,7 @@ func (c *NodeConfigCommand) Run(args []string) int {
 			c.Ui.Error(fmt.Sprintf("Error updating server list: %s", err))
 			return 1
 		}
-		c.Ui.Output(fmt.Sprint("Updated server list"))
+		c.Ui.Output("Updated server list")
 		return 0
 	}
 

command/node_drain.go

@@ -223,7 +223,7 @@ func (c *NodeDrainCommand) Run(args []string) int {
 
 	// Check if node exists
 	if len(nodeID) == 1 {
-		c.Ui.Error(fmt.Sprintf("Identifier must contain at least two characters."))
+		c.Ui.Error("Identifier must contain at least two characters.")
 		return 1
 	}
 

command/node_eligibility.go

@@ -123,7 +123,7 @@ func (c *NodeEligibilityCommand) Run(args []string) int {
 
 	// Check if node exists
 	if len(nodeID) == 1 {
-		c.Ui.Error(fmt.Sprintf("Identifier must contain at least two characters."))
+		c.Ui.Error("Identifier must contain at least two characters.")
 		return 1
 	}
 

command/node_status.go

@@ -239,7 +239,7 @@ func (c *NodeStatusCommand) Run(args []string) int {
 		}
 	}
 	if len(nodeID) == 1 {
-		c.Ui.Error(fmt.Sprintf("Identifier must contain at least two characters."))
+		c.Ui.Error("Identifier must contain at least two characters.")
 		return 1
 	}
 

command/operator_debug.go

@@ -373,9 +373,7 @@ func (c *OperatorDebugCommand) Run(args []string) int {
 			c.serverIDs = append(c.serverIDs, member.Name)
 		}
 	} else {
-		for _, id := range argNodes(serverIDs) {
-			c.serverIDs = append(c.serverIDs, id)
-		}
+		c.serverIDs = append(c.serverIDs, argNodes(serverIDs)...)
 	}
 
 	serversFound := 0
@@ -590,7 +588,7 @@ func (c *OperatorDebugCommand) collectAgentHost(path, id string, client *api.Cli
 
 		if strings.Contains(err.Error(), structs.ErrPermissionDenied.Error()) {
 			// Drop a hint to help the operator resolve the error
-			c.Ui.Warn(fmt.Sprintf("Agent host retrieval requires agent:read ACL or enable_debug=true.  See https://www.nomadproject.io/api-docs/agent#host for more information."))
+			c.Ui.Warn("Agent host retrieval requires agent:read ACL or enable_debug=true.  See https://www.nomadproject.io/api-docs/agent#host for more information.")
 		}
 		return // exit on any error
 	}
@@ -630,7 +628,7 @@ func (c *OperatorDebugCommand) collectPprof(path, id string, client *api.Client)
 			// one permission failure before we bail.
 			// But lets first drop a hint to help the operator resolve the error
 
-			c.Ui.Warn(fmt.Sprintf("Pprof retrieval requires agent:write ACL or enable_debug=true.  See https://www.nomadproject.io/api-docs/agent#agent-runtime-profiles for more information."))
+			c.Ui.Warn("Pprof retrieval requires agent:write ACL or enable_debug=true.  See https://www.nomadproject.io/api-docs/agent#agent-runtime-profiles for more information.")
 			return // only exit on 403
 		}
 	} else {

command/operator_keygen.go

@@ -38,7 +38,7 @@ func (c *OperatorKeygenCommand) Run(_ []string) int {
 		return 1
 	}
 	if n != 32 {
-		c.Ui.Error(fmt.Sprintf("Couldn't read enough entropy. Generate more entropy!"))
+		c.Ui.Error("Couldn't read enough entropy. Generate more entropy!")
 		return 1
 	}
 

command/operator_keyring.go

@@ -171,7 +171,7 @@ func (c *OperatorKeyringCommand) handleKeyResponse(resp *api.KeyringResponse) {
 	out[0] = "Key"
 	i := 1
 	for k := range resp.Keys {
-		out[i] = fmt.Sprintf("%s", k)
+		out[i] = k
 		i = i + 1
 	}
 	c.Ui.Output(formatList(out))

command/recommendation_apply.go

@@ -96,9 +96,7 @@ func (r *RecommendationApplyCommand) Run(args []string) int {
 
 	// Create a list of recommendations to apply.
 	ids := make([]string, len(args))
-	for i, id := range args {
-		ids[i] = id
-	}
+	copy(ids, args)
 
 	resp, _, err := client.Recommendations().Apply(ids, override)
 	if err != nil {

command/recommendation_dismiss.go

@@ -93,9 +93,7 @@ func (r *RecommendationDismissCommand) Run(args []string) int {
 
 	// Create a list of recommendations to dismiss.
 	ids := make([]string, len(args))
-	for i, id := range args {
-		ids[i] = id
-	}
+	copy(ids, args)
 
 	_, err = client.Recommendations().Delete(ids, nil)
 	if err != nil {

command/scaling_policy_list.go

@@ -168,8 +168,5 @@ func (s scalingPolicyStubList) Less(i, j int) bool {
 	stringList := []string{iTarget, jTarget}
 	sort.Strings(stringList)
 
-	if stringList[0] == iTarget {
-		return true
-	}
-	return false
+	return stringList[0] == iTarget
 }

command/status.go

@@ -184,6 +184,6 @@ func (c *StatusCommand) logMultiMatchError(id string, matches map[contexts.Conte
 		}
 
 		c.Ui.Error(fmt.Sprintf("\n%s:", strings.Title(string(ctx))))
-		c.Ui.Error(fmt.Sprintf("%s", strings.Join(vers, ", ")))
+		c.Ui.Error(strings.Join(vers, ", "))
 	}
 }

command/ui.go

@@ -182,6 +182,6 @@ func (c *UiCommand) logMultiMatchError(id string, matches map[contexts.Context][
 		}
 
 		c.Ui.Error(fmt.Sprintf("\n%s:", strings.Title(string(ctx))))
-		c.Ui.Error(fmt.Sprintf("%s", strings.Join(vers, ", ")))
+		c.Ui.Error(strings.Join(vers, ", "))
 	}
 }

command/volume_detach.go

@@ -52,9 +52,7 @@ func (c *VolumeDetachCommand) AutocompleteArgs() complete.Predictor {
 		if err != nil {
 			return []string{}
 		}
-		for _, match := range resp.Matches[contexts.Nodes] {
-			matches = append(matches, match)
-		}
+		matches = append(matches, resp.Matches[contexts.Nodes]...)
 		return matches
 	})
 }

drivers/docker/coordinator.go

@@ -154,9 +154,7 @@ func (d *dockerCoordinator) PullImage(image string, authOptions *docker.AuthConf
 	// Delete the future since we don't need it and we don't want to cache an
 	// image being there if it has possibly been manually deleted (outside of
 	// Nomad).
-	if _, ok := d.pullFutures[image]; ok {
-		delete(d.pullFutures, image)
-	}
+	delete(d.pullFutures, image)
 
 	// If we are cleaning up, we increment the reference count on the image
 	if err == nil && d.cleanup {
@@ -220,7 +218,6 @@ func (d *dockerCoordinator) pullImageImpl(image string, authOptions *docker.Auth
 	}
 
 	future.set(dockerImage.ID, nil)
-	return
 }
 
 // IncrementImageReference is used to increment an image reference count

drivers/docker/driver.go

@@ -1657,7 +1657,7 @@ func sliceMergeUlimit(ulimitsRaw map[string]string) ([]docker.ULimit, error) {
 			return []docker.ULimit{}, fmt.Errorf("Malformed ulimit specification %v: %q, cannot be empty", name, ulimitRaw)
 		}
 		// hard limit is optional
-		if strings.Contains(ulimitRaw, ":") == false {
+		if !strings.Contains(ulimitRaw, ":") {
 			ulimitRaw = ulimitRaw + ":" + ulimitRaw
 		}
 

drivers/docker/progress.go

@@ -103,7 +103,7 @@ func (p *imageProgress) get() (string, time.Time) {
 		}
 	}
 
-	elapsed := time.Now().Sub(p.pullStart)
+	elapsed := time.Since(p.pullStart)
 	cur := p.currentBytes()
 	total := p.totalBytes()
 	var est int64

drivers/mock/handle.go

@@ -94,5 +94,4 @@ func (h *taskHandle) run() {
 	}
 
 	h.exitResult = runCommand(h.command, stdout, stderr, h.killCh, pluginExitTimer, h.logger)
-	return
 }

drivers/qemu/driver.go

@@ -680,7 +680,7 @@ func (d *Driver) getMonitorPath(dir string, fingerPrint *drivers.Fingerprint) (s
 		d.logger.Debug("long socket paths available in this version of QEMU", "version", currentQemuVer)
 	}
 	fullSocketPath := fmt.Sprintf("%s/%s", dir, qemuMonitorSocketName)
-	if len(fullSocketPath) > qemuLegacyMaxMonitorPathLen && longPathSupport == false {
+	if len(fullSocketPath) > qemuLegacyMaxMonitorPathLen && !longPathSupport {
 		return "", fmt.Errorf("monitor path is too long for this version of qemu")
 	}
 	return fullSocketPath, nil

e2e/cli/command/run.go

@@ -172,7 +172,7 @@ func (c *Run) Run(args []string) int {
 	}
 
 	if len(failedEnvs) > 0 {
-		c.Ui.Error(fmt.Sprintf("The following environments ***FAILED***"))
+		c.Ui.Error("The following environments ***FAILED***")
 		for name, report := range failedEnvs {
 			c.Ui.Error(fmt.Sprintf("  [%s]: %d out of %d suite failures",
 				name, report.TotalFailedSuites, report.TotalSuites))

e2e/framework/framework.go

@@ -259,10 +259,5 @@ func (f *Framework) runCase(t *testing.T, s *TestSuite, c TestCase) {
 }
 
 func isTestMethod(m string) bool {
-	if !strings.HasPrefix(m, "Test") {
-		return false
-	}
-
-	// THINKING: adding flag to target a specific test or test regex?
-	return true
+	return strings.HasPrefix(m, "Test")
 }

e2e/vaultsecrets/vaultsecrets.go

@@ -189,7 +189,7 @@ func (tc *VaultSecretsTest) TestVaultSecrets(f *framework.F) {
 		fmt.Sprintf("%s/myapp", tc.secretsPath), "key=UPDATED")
 	f.NoError(err, out)
 
-	elapsed := time.Now().Sub(ttlStart)
+	elapsed := time.Since(ttlStart)
 	time.Sleep((time.Second * 60) - elapsed)
 
 	// tokens will not be updated

helper/flatmap/flatmap.go

@@ -17,9 +17,7 @@ func Flatten(obj interface{}, filter []string, primitiveOnly bool) map[string]st
 
 	flatten("", v, primitiveOnly, false, flat)
 	for _, f := range filter {
-		if _, ok := flat[f]; ok {
-			delete(flat, f)
-		}
+		delete(flat, f)
 	}
 	return flat
 }
@@ -116,7 +114,7 @@ func getSubPrefix(curPrefix, subField string) string {
 	if curPrefix != "" {
 		return fmt.Sprintf("%s.%s", curPrefix, subField)
 	}
-	return fmt.Sprintf("%s", subField)
+	return subField
 }
 
 // getSubKeyPrefix takes the current prefix and the next subfield and returns an
@@ -125,5 +123,5 @@ func getSubKeyPrefix(curPrefix, subField string) string {
 	if curPrefix != "" {
 		return fmt.Sprintf("%s[%s]", curPrefix, subField)
 	}
-	return fmt.Sprintf("%s", subField)
+	return subField
 }

helper/funcs.go

@@ -366,9 +366,7 @@ func CopySliceString(s []string) []string {
 	}
 
 	c := make([]string, l)
-	for i, v := range s {
-		c[i] = v
-	}
+	copy(c, s)
 	return c
 }
 
@@ -379,9 +377,7 @@ func CopySliceInt(s []int) []int {
 	}
 
 	c := make([]int, l)
-	for i, v := range s {
-		c[i] = v
-	}
+	copy(c, s)
 	return c
 }
 

helper/grpc-middleware/logging/client_interceptors.go

@@ -35,7 +35,7 @@ func StreamClientInterceptor(logger hclog.Logger, opts ...Option) grpc.StreamCli
 func emitClientLog(logger hclog.Logger, o *options, fullMethodString string, startTime time.Time, err error, msg string) {
 	code := status.Code(err)
 	logLevel := o.levelFunc(code)
-	reqDuration := time.Now().Sub(startTime)
+	reqDuration := time.Since(startTime)
 	service := path.Dir(fullMethodString)[1:]
 	method := path.Base(fullMethodString)
 	logger.Log(logLevel, msg, "grpc.code", code, "duration", reqDuration, "grpc.service", service, "grpc.method", method)

helper/pluginutils/hclutils/util.go

@@ -85,7 +85,7 @@ func formattedDiagnosticErrors(diag hcl.Diagnostics) []error {
 		if d.Summary == "Extraneous JSON object property" {
 			d.Summary = "Invalid label"
 		}
-		err := errors.New(fmt.Sprintf("%s: %s", d.Summary, d.Detail))
+		err := fmt.Errorf("%s: %s", d.Summary, d.Detail)
 		errs = append(errs, err)
 	}
 	return errs

helper/tlsutil/config.go

@@ -309,18 +309,15 @@ func (c *Config) OutgoingTLSWrapper() (RegionWrapper, error) {
 // no longer supports this mode of operation, we have to do it
 // manually.
 func WrapTLSClient(conn net.Conn, tlsConfig *tls.Config) (net.Conn, error) {
-	var err error
-	var tlsConn *tls.Conn
-
-	tlsConn = tls.Client(conn, tlsConfig)
+	tlsConn := tls.Client(conn, tlsConfig)
 
 	// If crypto/tls is doing verification, there's no need to do
 	// our own.
-	if tlsConfig.InsecureSkipVerify == false {
+	if !tlsConfig.InsecureSkipVerify {
 		return tlsConn, nil
 	}
 
-	if err = tlsConn.Handshake(); err != nil {
+	if err := tlsConn.Handshake(); err != nil {
 		tlsConn.Close()
 		return nil, err
 	}
@@ -342,13 +339,13 @@ func WrapTLSClient(conn net.Conn, tlsConfig *tls.Config) (net.Conn, error) {
 		opts.Intermediates.AddCert(cert)
 	}
 
-	_, err = certs[0].Verify(opts)
+	_, err := certs[0].Verify(opts)
 	if err != nil {
 		tlsConn.Close()
 		return nil, err
 	}
 
-	return tlsConn, err
+	return tlsConn, nil
 }
 
 // IncomingTLSConfig generates a TLS configuration for incoming requests

jobspec/parse.go

@@ -332,7 +332,7 @@ func parseSpread(result *[]*api.Spread, list *ast.ObjectList) error {
 		// Parse spread target
 		if o := listVal.Filter("target"); len(o.Items) > 0 {
 			if err := parseSpreadTarget(&s.SpreadTarget, o); err != nil {
-				return multierror.Prefix(err, fmt.Sprintf("target ->"))
+				return multierror.Prefix(err, "target ->")
 			}
 		}
 

nomad/client_agent_endpoint.go

@@ -198,10 +198,7 @@ func (a *Agent) monitor(conn io.ReadWriteCloser) {
 			cancel()
 			return
 		}
-		select {
-		case <-ctx.Done():
-			return
-		}
+		<-ctx.Done()
 	}()
 
 	logCh := monitor.Start()
@@ -351,7 +348,6 @@ func (a *Agent) forwardMonitorClient(conn io.ReadWriteCloser, args cstructs.Moni
 	}
 
 	structs.Bridge(conn, clientConn)
-	return
 }
 
 func (a *Agent) forwardMonitorServer(conn io.ReadWriteCloser, server *serverParts, args cstructs.MonitorRequest, encoder *codec.Encoder, decoder *codec.Decoder) {
@@ -373,8 +369,8 @@ func (a *Agent) forwardMonitorServer(conn io.ReadWriteCloser, server *serverPart
 	}
 
 	structs.Bridge(conn, serverConn)
-	return
 }
+
 func (a *Agent) forwardProfileClient(args *structs.AgentPprofRequest, reply *structs.AgentPprofResponse) error {
 	state, srv, err := a.findClientConn(args.NodeID)
 

nomad/client_alloc_endpoint.go

@@ -389,5 +389,4 @@ func (a *ClientAllocations) exec(conn io.ReadWriteCloser) {
 	}
 
 	structs.Bridge(conn, clientConn)
-	return
 }

nomad/client_fs_endpoint.go

@@ -318,7 +318,6 @@ func (f *FileSystem) stream(conn io.ReadWriteCloser) {
 	}
 
 	structs.Bridge(conn, clientConn)
-	return
 }
 
 // logs is used to access an task's logs for a given allocation
@@ -440,5 +439,4 @@ func (f *FileSystem) logs(conn io.ReadWriteCloser) {
 	}
 
 	structs.Bridge(conn, clientConn)
-	return
 }

nomad/deploymentwatcher/deployment_watcher.go

@@ -412,7 +412,7 @@ func (w *deploymentWatcher) watch() {
 			<-deadlineTimer.C
 		}
 	} else {
-		deadlineTimer = time.NewTimer(currentDeadline.Sub(time.Now()))
+		deadlineTimer = time.NewTimer(time.Until(currentDeadline))
 	}
 
 	allocIndex := uint64(1)
@@ -474,7 +474,7 @@ FAIL:
 				// rollout, the next progress deadline becomes zero, so we want
 				// to avoid resetting, causing a deployment failure.
 				if !next.IsZero() {
-					deadlineTimer.Reset(next.Sub(time.Now()))
+					deadlineTimer.Reset(time.Until(next))
 				}
 			}
 

nomad/drainer/drain_heap.go

@@ -95,7 +95,7 @@ func (d *deadlineHeap) watch() {
 		// deadline is in the future, see if we already have a timer setup to
 		// handle it. If we don't create the timer.
 		if deadline.IsZero() || !deadline.Equal(nextDeadline) {
-			timer.Reset(deadline.Sub(time.Now()))
+			timer.Reset(time.Until(deadline))
 			nextDeadline = deadline
 		}
 	}

nomad/rpc.go

@@ -559,7 +559,7 @@ CHECK_LEADER:
 	if firstCheck.IsZero() {
 		firstCheck = time.Now()
 	}
-	if time.Now().Sub(firstCheck) < r.config.RPCHoldTimeout {
+	if time.Since(firstCheck) < r.config.RPCHoldTimeout {
 		jitter := lib.RandomStagger(r.config.RPCHoldTimeout / structs.JitterFraction)
 		select {
 		case <-time.After(jitter):
@@ -749,7 +749,7 @@ func (r *rpcHandler) setQueryMeta(m *structs.QueryMeta) {
 		m.LastContact = 0
 		m.KnownLeader = true
 	} else {
-		m.LastContact = time.Now().Sub(r.raft.LastContact())
+		m.LastContact = time.Since(r.raft.LastContact())
 		m.KnownLeader = (r.raft.Leader() != "")
 	}
 }

nomad/state/schema.go

@@ -287,7 +287,7 @@ func jobIsPeriodic(obj interface{}) (bool, error) {
 		return false, fmt.Errorf("Unexpected type: %v", obj)
 	}
 
-	if j.Periodic != nil && j.Periodic.Enabled == true {
+	if j.Periodic != nil && j.Periodic.Enabled {
 		return true, nil
 	}
 

nomad/structs/config/tls.go

@@ -185,13 +185,13 @@ func (t *TLSConfig) IsEmpty() bool {
 		return true
 	}
 
-	return t.EnableHTTP == false &&
-		t.EnableRPC == false &&
-		t.VerifyServerHostname == false &&
+	return !t.EnableHTTP &&
+		!t.EnableRPC &&
+		!t.VerifyServerHostname &&
 		t.CAFile == "" &&
 		t.CertFile == "" &&
 		t.KeyFile == "" &&
-		t.VerifyHTTPSClient == false
+		!t.VerifyHTTPSClient
 }
 
 // Merge is used to merge two TLS configs together

nomad/structs/diff.go

@@ -1060,12 +1060,12 @@ func connectGatewayProxyDiff(prev, next *ConsulGatewayProxy, contextual bool) *O
 		if prev.ConnectTimeout == nil {
 			oldPrimitiveFlat["ConnectTimeout"] = ""
 		} else {
-			oldPrimitiveFlat["ConnectTimeout"] = fmt.Sprintf("%s", *prev.ConnectTimeout)
+			oldPrimitiveFlat["ConnectTimeout"] = prev.ConnectTimeout.String()
 		}
 		if next.ConnectTimeout == nil {
 			newPrimitiveFlat["ConnectTimeout"] = ""
 		} else {
-			newPrimitiveFlat["ConnectTimeout"] = fmt.Sprintf("%s", *next.ConnectTimeout)
+			newPrimitiveFlat["ConnectTimeout"] = next.ConnectTimeout.String()
 		}
 	}
 

nomad/structs/structs.go

@@ -3527,11 +3527,7 @@ func (a *AllocatedTaskResources) Comparable() *ComparableResources {
 			},
 		},
 	}
-	if len(a.Networks) > 0 {
-		for _, net := range a.Networks {
-			ret.Flattened.Networks = append(ret.Flattened.Networks, net)
-		}
-	}
+	ret.Flattened.Networks = append(ret.Flattened.Networks, a.Networks...)
 	return ret
 }
 
@@ -4722,9 +4718,7 @@ func (m *Multiregion) Copy() *Multiregion {
 			Datacenters: []string{},
 			Meta:        map[string]string{},
 		}
-		for _, dc := range region.Datacenters {
-			copyRegion.Datacenters = append(copyRegion.Datacenters, dc)
-		}
+		copyRegion.Datacenters = append(copyRegion.Datacenters, region.Datacenters...)
 		for k, v := range region.Meta {
 			copyRegion.Meta[k] = v
 		}
@@ -8367,15 +8361,15 @@ func (s *Spread) Validate() error {
 		if !ok {
 			seen[target.Value] = struct{}{}
 		} else {
-			mErr.Errors = append(mErr.Errors, errors.New(fmt.Sprintf("Spread target value %q already defined", target.Value)))
+			mErr.Errors = append(mErr.Errors, fmt.Errorf("Spread target value %q already defined", target.Value))
 		}
 		if target.Percent < 0 || target.Percent > 100 {
-			mErr.Errors = append(mErr.Errors, errors.New(fmt.Sprintf("Spread target percentage for value %q must be between 0 and 100", target.Value)))
+			mErr.Errors = append(mErr.Errors, fmt.Errorf("Spread target percentage for value %q must be between 0 and 100", target.Value))
 		}
 		sumPercent += uint32(target.Percent)
 	}
 	if sumPercent > 100 {
-		mErr.Errors = append(mErr.Errors, errors.New(fmt.Sprintf("Sum of spread target percentages must not be greater than 100%%; got %d%%", sumPercent)))
+		mErr.Errors = append(mErr.Errors, fmt.Errorf("Sum of spread target percentages must not be greater than 100%%; got %d%%", sumPercent))
 	}
 	return mErr.ErrorOrNil()
 }
@@ -9608,11 +9602,9 @@ func (a *AllocListStub) SetEventDisplayMessages() {
 }
 
 func setDisplayMsg(taskStates map[string]*TaskState) {
-	if taskStates != nil {
-		for _, taskState := range taskStates {
-			for _, event := range taskState.Events {
-				event.PopulateEventDisplayMessage()
-			}
+	for _, taskState := range taskStates {
+		for _, event := range taskState.Events {
+			event.PopulateEventDisplayMessage()
 		}
 	}
 }
@@ -10504,7 +10496,7 @@ func (p *PlanResult) FullCommit(plan *Plan) (bool, int, int) {
 	expected := 0
 	actual := 0
 	for name, allocList := range plan.NodeAllocation {
-		didAlloc, _ := p.NodeAllocation[name]
+		didAlloc := p.NodeAllocation[name]
 		expected += len(allocList)
 		actual += len(didAlloc)
 	}

nomad/vault.go

@@ -330,8 +330,6 @@ func (v *vaultClient) SetActive(active bool) {
 	v.revLock.Lock()
 	v.revoking = make(map[*structs.VaultAccessor]time.Time)
 	v.revLock.Unlock()
-
-	return
 }
 
 // flush is used to reset the state of the vault client
@@ -557,7 +555,7 @@ func (v *vaultClient) renewalLoop() {
 			// Successfully renewed
 			if err == nil {
 				// Attempt to renew the token at half the expiration time
-				durationUntilRenew := currentExpiration.Sub(time.Now()) / 2
+				durationUntilRenew := time.Until(currentExpiration) / 2
 
 				v.logger.Info("successfully renewed token", "next_renewal", durationUntilRenew)
 				authRenewTimer.Reset(durationUntilRenew)

plugins/drivers/testutils/exec_testing.go

@@ -197,7 +197,7 @@ func TestExecFSIsolation(t *testing.T, driver *DriverHarness, taskID string) {
 
 		// we always run in a cgroup - testing freezer cgroup
 		r = execTask(t, driver, taskID,
-			fmt.Sprintf("cat /proc/self/cgroup"),
+			"cat /proc/self/cgroup",
 			false, "")
 		require.Zero(t, r.exitCode)
 

plugins/shared/structs/attribute.go

@@ -296,16 +296,11 @@ func (a *Attribute) Comparable(b *Attribute) bool {
 	}
 
 	if a.String != nil {
-		if b.String != nil {
-			return true
-		}
-		return false
+		return b.String != nil
 	}
+
 	if a.Bool != nil {
-		if b.Bool != nil {
-			return true
-		}
-		return false
+		return b.Bool != nil
 	}
 
 	return true

scheduler/feasible.go

@@ -348,12 +348,8 @@ func (c *NetworkChecker) SetNetwork(network *structs.NetworkResource) {
 	}
 
 	c.ports = make([]structs.Port, len(network.DynamicPorts)+len(network.ReservedPorts))
-	for _, port := range network.DynamicPorts {
-		c.ports = append(c.ports, port)
-	}
-	for _, port := range network.ReservedPorts {
-		c.ports = append(c.ports, port)
-	}
+	c.ports = append(c.ports, network.DynamicPorts...)
+	c.ports = append(c.ports, network.ReservedPorts...)
 }
 
 func (c *NetworkChecker) Feasible(option *structs.Node) bool {

scheduler/generic_sched.go

@@ -705,7 +705,7 @@ func updateRescheduleTracker(alloc *structs.Allocation, prev *structs.Allocation
 
 // findPreferredNode finds the preferred node for an allocation
 func (s *GenericScheduler) findPreferredNode(place placementResult) (*structs.Node, error) {
-	if prev := place.PreviousAllocation(); prev != nil && place.TaskGroup().EphemeralDisk.Sticky == true {
+	if prev := place.PreviousAllocation(); prev != nil && place.TaskGroup().EphemeralDisk.Sticky {
 		var preferredNode *structs.Node
 		ws := memdb.NewWatchSet()
 		preferredNode, err := s.state.NodeByID(ws, prev.NodeID)

scheduler/reconcile.go

@@ -466,9 +466,7 @@ func (a *allocReconciler) computeGroup(group string, all allocSet) bool {
 
 	if deploymentPlaceReady {
 		desiredChanges.Place += uint64(len(place))
-		for _, p := range place {
-			a.result.place = append(a.result.place, p)
-		}
+		a.result.place = append(a.result.place, place...)
 		a.markStop(rescheduleNow, "", allocRescheduled)
 		desiredChanges.Stop += uint64(len(rescheduleNow))
 
@@ -481,9 +479,7 @@ func (a *allocReconciler) computeGroup(group string, all allocSet) bool {
 		if len(lost) != 0 {
 			allowed := helper.IntMin(len(lost), len(place))
 			desiredChanges.Place += uint64(allowed)
-			for _, p := range place[:allowed] {
-				a.result.place = append(a.result.place, p)
-			}
+			a.result.place = append(a.result.place, place[:allowed]...)
 		}
 
 		// Handle rescheduling of failed allocations even if the deployment is

version/version.go

@@ -50,7 +50,7 @@ func GetVersion() *VersionInfo {
 }
 
 func (c *VersionInfo) VersionNumber() string {
-	version := fmt.Sprintf("%s", c.Version)
+	version := c.Version
 
 	if c.VersionPrerelease != "" {
 		version = fmt.Sprintf("%s-%s", version, c.VersionPrerelease)