Dockerfile: update golangci-lint to v2.9.0 and fix linting

cli-plugins/manager/cobra.go

@@ -57,7 +57,7 @@ func AddPluginCommandStubs(dockerCLI config.Provider, rootCmd *cobra.Command) (e
 				},
 				ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 					// Delegate completion to plugin
-					cargs := []string{p.Path, cobra.ShellCompRequestCmd, p.Name}
+					cargs := []string{p.Path, cobra.ShellCompRequestCmd, p.Name} //nolint:prealloc // no need to over-complicate things.
 					cargs = append(cargs, args...)
 					cargs = append(cargs, toComplete)
 					os.Args = cargs

cli/command/formatter/container.go

@@ -350,7 +350,7 @@ func DisplayablePorts(ports []container.PortSummary) string {
 		last  uint16
 	}
 	groupMap := make(map[string]*portGroup)
-	var result []string //nolint:prealloc
+	var result []string
 	var hostMappings []string
 	var groupMapKeys []string
 	sort.Slice(ports, func(i, j int) bool {

cli/command/image/build_test.go

@@ -190,7 +190,7 @@ func (f *fakeBuild) build(_ context.Context, buildContext io.Reader, options cli
 
 func (f *fakeBuild) headers(t *testing.T) []*tar.Header {
 	t.Helper()
-	headers := []*tar.Header{}
+	var headers []*tar.Header
 	for {
 		hdr, err := f.context.Next()
 		switch err {
@@ -206,8 +206,9 @@ func (f *fakeBuild) headers(t *testing.T) []*tar.Header {
 
 func (f *fakeBuild) filenames(t *testing.T) []string {
 	t.Helper()
-	names := []string{}
-	for _, header := range f.headers(t) {
+	h := f.headers(t)
+	names := make([]string, 0, len(h))
+	for _, header := range h {
 		names = append(names, header.Name)
 	}
 	sort.Strings(names)

cli/command/service/list_test.go

@@ -108,7 +108,7 @@ func TestServiceListServiceStatus(t *testing.T) {
 		},
 	}
 
-	matrix := make([]testCase, 0)
+	matrix := make([]testCase, 0, len(tests))
 	for _, quiet := range []bool{false, true} {
 		for _, tc := range tests {
 			if quiet {

cli/command/service/progress/progress_test.go

@@ -80,7 +80,7 @@ func TestReplicatedProgressUpdaterOneReplica(t *testing.T) {
 		service:     service,
 	}
 
-	tasks := []swarm.Task{}
+	var tasks []swarm.Task //nolint:prealloc // no need to over-complicate things.
 
 	ut.testUpdater(tasks, false,
 		[]progress.Progress{
@@ -193,7 +193,7 @@ func TestReplicatedProgressUpdaterManyReplicas(t *testing.T) {
 		service:     service,
 	}
 
-	tasks := []swarm.Task{}
+	var tasks []swarm.Task
 
 	// No per-task progress bars because there are too many replicas
 	ut.testUpdater(tasks, false,
@@ -248,7 +248,7 @@ func TestGlobalProgressUpdaterOneNode(t *testing.T) {
 		service:     service,
 	}
 
-	tasks := []swarm.Task{}
+	var tasks []swarm.Task //nolint:prealloc // no need to over-complicate things.
 
 	ut.testUpdater(tasks, false,
 		[]progress.Progress{
@@ -362,7 +362,7 @@ func TestGlobalProgressUpdaterManyNodes(t *testing.T) {
 		ut.activeNodes[strconv.Itoa(i)] = struct{}{}
 	}
 
-	tasks := []swarm.Task{}
+	var tasks []swarm.Task
 
 	ut.testUpdater(tasks, false,
 		[]progress.Progress{
@@ -459,25 +459,24 @@ func TestReplicatedJobProgressUpdaterSmall(t *testing.T) {
 	})
 
 	// wipe the old tasks out of the list
-	tasks = []swarm.Task{}
-	tasks = append(tasks,
-		swarm.Task{
+	tasks = []swarm.Task{ //nolint:prealloc // no need to over-complicate things.
+		{
 			ID:           "task1",
 			Slot:         0,
 			NodeID:       "",
 			DesiredState: swarm.TaskStateComplete,
 			Status:       swarm.TaskStatus{State: swarm.TaskStateNew},
 			JobIteration: &swarm.Version{Index: service.JobStatus.JobIteration.Index},
 		},
-		swarm.Task{
+		{
 			ID:           "task2",
 			Slot:         1,
 			NodeID:       "",
 			DesiredState: swarm.TaskStateComplete,
 			Status:       swarm.TaskStatus{State: swarm.TaskStateNew},
 			JobIteration: &swarm.Version{Index: service.JobStatus.JobIteration.Index},
 		},
-	)
+	}
 	ut.testUpdater(tasks, false, []progress.Progress{
 		{ID: "1/5", Action: "new      ", Current: 1, Total: 10, HideCounts: true},
 		{ID: "2/5", Action: "new      ", Current: 1, Total: 10, HideCounts: true},
@@ -644,7 +643,7 @@ func TestReplicatedJobProgressUpdaterLarge(t *testing.T) {
 		service:     service,
 	}
 
-	tasks := []swarm.Task{}
+	var tasks []swarm.Task
 
 	// see the comments in TestReplicatedJobProgressUpdaterSmall for why
 	// we write this out twice.
@@ -741,7 +740,7 @@ func TestGlobalJobProgressUpdaterSmall(t *testing.T) {
 		service:     service,
 	}
 
-	tasks := []swarm.Task{
+	tasks := []swarm.Task{ //nolint:prealloc // no need to over-complicate things.
 		{
 			ID:           "oldtask1",
 			DesiredState: swarm.TaskStateComplete,
@@ -871,7 +870,7 @@ func TestGlobalJobProgressUpdaterLarge(t *testing.T) {
 		service:     service,
 	}
 
-	tasks := []swarm.Task{}
+	var tasks []swarm.Task //nolint:prealloc // no need to over-complicate things.
 	for nodeID := range activeNodes {
 		tasks = append(tasks, swarm.Task{
 			ID:           "task" + nodeID,

cli/command/service/update.go

@@ -1333,7 +1333,7 @@ func updateNetworks(ctx context.Context, apiClient client.NetworkAPIClient, flag
 	}
 
 	existingNetworks := make(map[string]struct{})
-	var newNetworks []swarm.NetworkAttachmentConfig //nolint:prealloc
+	var newNetworks []swarm.NetworkAttachmentConfig
 	for _, nw := range specNetworks {
 		if _, exists := idsToRemove[nw.Target]; exists {
 			continue

cli/command/stack/loader.go

@@ -27,7 +27,6 @@ func loadComposeFile(streams command.Streams, opts deployOptions) (*composetypes
 		return nil, err
 	}
 
-	dicts := getDictsFrom(configDetails.ConfigFiles)
 	config, err := loader.Load(configDetails)
 	if err != nil {
 		var fpe *loader.ForbiddenPropertiesError
@@ -39,6 +38,7 @@ func loadComposeFile(streams command.Streams, opts deployOptions) (*composetypes
 		return nil, err
 	}
 
+	dicts := getDictsFrom(configDetails.ConfigFiles)
 	unsupportedProperties := loader.GetUnsupportedProperties(dicts...)
 	if len(unsupportedProperties) > 0 {
 		_, _ = fmt.Fprintf(streams.Err(), "Ignoring unsupported options: %s\n\n",
@@ -65,8 +65,7 @@ func loadComposeFile(streams command.Streams, opts deployOptions) (*composetypes
 }
 
 func getDictsFrom(configFiles []composetypes.ConfigFile) []map[string]any {
-	dicts := []map[string]any{}
-
+	dicts := make([]map[string]any, 0, len(configFiles))
 	for _, configFile := range configFiles {
 		dicts = append(dicts, configFile.Config)
 	}

cli/command/swarm/opts.go

@@ -110,7 +110,7 @@ func (*ExternalCAOption) Type() string {
 
 // String returns a string repr of this option.
 func (m *ExternalCAOption) String() string {
-	externalCAs := []string{}
+	externalCAs := make([]string, 0, len(m.values))
 	for _, externalCA := range m.values {
 		repr := fmt.Sprintf("%s: %s", externalCA.Protocol, externalCA.URL)
 		externalCAs = append(externalCAs, repr)

cli/command/system/events.go

@@ -133,12 +133,12 @@ func prettyPrintEvent(out io.Writer, event events.Message) error {
 	_, _ = fmt.Fprintf(out, "%s %s %s", event.Type, event.Action, event.Actor.ID)
 
 	if len(event.Actor.Attributes) > 0 {
-		var attrs []string
-		var keys []string
+		keys := make([]string, 0, len(event.Actor.Attributes))
 		for k := range event.Actor.Attributes {
 			keys = append(keys, k)
 		}
 		sort.Strings(keys)
+		attrs := make([]string, 0, len(keys))
 		for _, k := range keys {
 			v := event.Actor.Attributes[k]
 			attrs = append(attrs, k+"="+v)

cli/compose/convert/service.go

@@ -174,7 +174,11 @@ func Service(
 }
 
 func getPlacementPreference(preferences []composetypes.PlacementPreferences) []swarm.PlacementPreference {
-	result := []swarm.PlacementPreference{}
+	if len(preferences) == 0 {
+		return nil
+	}
+
+	result := make([]swarm.PlacementPreference, 0, len(preferences))
 	for _, preference := range preferences {
 		spreadDescriptor := preference.Spread
 		result = append(result, swarm.PlacementPreference{
@@ -198,7 +202,7 @@ func convertServiceNetworks(
 		}
 	}
 
-	nets := []swarm.NetworkAttachmentConfig{}
+	nets := make([]swarm.NetworkAttachmentConfig, 0, len(networks))
 	for networkName, nw := range networks {
 		networkConfig, ok := networkConfigs[networkName]
 		if !ok && networkName != defaultNetwork {
@@ -241,15 +245,15 @@ func convertServiceSecrets(
 	secrets []composetypes.ServiceSecretConfig,
 	secretSpecs map[string]composetypes.SecretConfig,
 ) ([]*swarm.SecretReference, error) {
-	refs := []*swarm.SecretReference{}
-
 	lookup := func(key string) (composetypes.FileObjectConfig, error) {
 		secretSpec, exists := secretSpecs[key]
 		if !exists {
 			return composetypes.FileObjectConfig{}, fmt.Errorf("undefined secret %q", key)
 		}
 		return composetypes.FileObjectConfig(secretSpec), nil
 	}
+
+	refs := make([]*swarm.SecretReference, 0, len(secrets))
 	for _, secret := range secrets {
 		obj, err := convertFileObject(namespace, composetypes.FileReferenceConfig(secret), lookup)
 		if err != nil {
@@ -564,7 +568,7 @@ func convertResources(source composetypes.Resources) (*swarm.ResourceRequirement
 }
 
 func convertEndpointSpec(endpointMode string, source []composetypes.ServicePortConfig) *swarm.EndpointSpec {
-	portConfigs := []swarm.PortConfig{}
+	portConfigs := make([]swarm.PortConfig, 0, len(source))
 	for _, port := range source {
 		portConfig := swarm.PortConfig{
 			Protocol:      network.IPProtocol(port.Protocol),

cli/compose/loader/merge.go

@@ -134,7 +134,7 @@ func toServiceVolumeConfigsMap(s any) (map[any]any, error) {
 }
 
 func toServiceSecretConfigsSlice(dst reflect.Value, m map[any]any) error {
-	s := []types.ServiceSecretConfig{}
+	s := make([]types.ServiceSecretConfig, 0, len(m))
 	for _, v := range m {
 		s = append(s, v.(types.ServiceSecretConfig))
 	}
@@ -144,7 +144,7 @@ func toServiceSecretConfigsSlice(dst reflect.Value, m map[any]any) error {
 }
 
 func toSServiceConfigObjConfigsSlice(dst reflect.Value, m map[any]any) error {
-	s := []types.ServiceConfigObjConfig{}
+	s := make([]types.ServiceConfigObjConfig, 0, len(m))
 	for _, v := range m {
 		s = append(s, v.(types.ServiceConfigObjConfig))
 	}
@@ -154,7 +154,7 @@ func toSServiceConfigObjConfigsSlice(dst reflect.Value, m map[any]any) error {
 }
 
 func toServicePortConfigsSlice(dst reflect.Value, m map[any]any) error {
-	s := []types.ServicePortConfig{}
+	s := make([]types.ServicePortConfig, 0, len(m))
 	for _, v := range m {
 		s = append(s, v.(types.ServicePortConfig))
 	}
@@ -164,7 +164,7 @@ func toServicePortConfigsSlice(dst reflect.Value, m map[any]any) error {
 }
 
 func toServiceVolumeConfigsSlice(dst reflect.Value, m map[any]any) error {
-	s := []types.ServiceVolumeConfig{}
+	s := make([]types.ServiceVolumeConfig, 0, len(m))
 	for _, v := range m {
 		s = append(s, v.(types.ServiceVolumeConfig))
 	}

cli/connhelper/ssh/ssh.go

@@ -175,7 +175,7 @@ func quoteCommand(commandAndArgs ...string) (string, error) {
 			quotedCmd = a
 			continue
 		}
-		quotedCmd += " " + a //nolint:perfsprint // ignore "concat-loop"; no need to use a string-builder for this.
+		quotedCmd += " " + a
 	}
 	// each part is quoted appropriately, so now we'll have a full
 	// shell command to pass off to "ssh"

dockerfiles/Dockerfile.lint

@@ -7,7 +7,7 @@ ARG GO_VERSION=1.25.7
 # that's also available as alpine image variant for the Golang version used.
 ARG ALPINE_VERSION=3.22
 # GOLANGCI_LINT_VERSION sets the version of the golangci/golangci-lint image to use.
-ARG GOLANGCI_LINT_VERSION=v2.6.1
+ARG GOLANGCI_LINT_VERSION=v2.9.0
 
 FROM golangci/golangci-lint:${GOLANGCI_LINT_VERSION}-alpine AS golangci-lint
 

internal/volumespec/volumespec.go

@@ -25,7 +25,7 @@ func Parse(spec string) (VolumeConfig, error) {
 		return volume, nil
 	}
 
-	var buffer []rune
+	buffer := make([]rune, 0, len(spec))
 	for _, char := range spec + string(endOfSpec) {
 		switch {
 		case isWindowsDrive(buffer, char):
@@ -35,7 +35,7 @@ func Parse(spec string) (VolumeConfig, error) {
 				populateType(&volume)
 				return volume, fmt.Errorf("invalid spec: %s: %w", spec, err)
 			}
-			buffer = []rune{}
+			buffer = buffer[:0] // reset, but reuse capacity
 		default:
 			buffer = append(buffer, char)
 		}

opts/gpus.go

@@ -105,7 +105,7 @@ func (*GpuOpts) Type() string {
 
 // String returns a string repr of this option
 func (o *GpuOpts) String() string {
-	gpus := []string{}
+	gpus := make([]string, 0, len(o.values))
 	for _, gpu := range o.values {
 		gpus = append(gpus, fmt.Sprintf("%v", gpu))
 	}

opts/mount.go

@@ -151,7 +151,7 @@ func (*MountOpt) Type() string {
 
 // String returns a string repr of this option
 func (m *MountOpt) String() string {
-	mounts := []string{}
+	mounts := make([]string, 0, len(m.values))
 	for _, mount := range m.values {
 		repr := fmt.Sprintf("%s %s %s", mount.Type, mount.Source, mount.Target)
 		mounts = append(mounts, repr)

opts/swarmopts/config.go

@@ -86,7 +86,7 @@ func (*ConfigOpt) Type() string {
 
 // String returns a string repr of this option
 func (o *ConfigOpt) String() string {
-	configs := []string{}
+	configs := make([]string, 0, len(o.values))
 	for _, config := range o.values {
 		repr := fmt.Sprintf("%s -> %s", config.ConfigName, config.File.Name)
 		configs = append(configs, repr)

opts/swarmopts/secret.go

@@ -85,7 +85,7 @@ func (*SecretOpt) Type() string {
 
 // String returns a string repr of this option
 func (o *SecretOpt) String() string {
-	secrets := []string{}
+	secrets := make([]string, 0, len(o.values))
 	for _, secret := range o.values {
 		repr := fmt.Sprintf("%s -> %s", secret.SecretName, secret.File.Name)
 		secrets = append(secrets, repr)