Fix some linting warnings. (#149)

acctest/pluginacc.go

@@ -59,9 +59,7 @@ type TestTeardownFunc func() error
 //nolint:errcheck
 func TestPlugin(t *testing.T, testCase *PluginTestCase) {
 	if os.Getenv(TestEnvVar) == "" {
-		t.Skip(fmt.Sprintf(
-			"Acceptance tests skipped unless env '%s' set",
-			TestEnvVar))
+		t.Skipf("Acceptance tests skipped unless env '%s' set", TestEnvVar)
 		return
 	}
 

adapter/adapter.go

@@ -105,7 +105,6 @@ func (c *Adapter) handleSession(newChannel ssh.NewChannel) error {
 	// Sessions have requests such as "pty-req", "shell", "env", and "exec".
 	// see RFC 4254, section 6
 	go func(in <-chan *ssh.Request) {
-		env := make([]envRequestPayload, 4)
 		for req := range in {
 			switch req.Type {
 			case "pty-req":
@@ -120,7 +119,6 @@ func (c *Adapter) handleSession(newChannel ssh.NewChannel) error {
 					req.Reply(false, nil)
 					continue
 				}
-				env = append(env, req.Payload)
 				log.Printf("new env request: %s", req.Payload)
 				req.Reply(true, nil)
 			case "exec":
@@ -207,7 +205,7 @@ func (c *Adapter) exec(command string, in io.Reader, out io.Writer, err io.Write
 
 func serveSCP(args string) bool {
 	opts, _ := scpOptions(args)
-	return bytes.IndexAny(opts, "tf") >= 0
+	return bytes.ContainsAny(opts, "tf")
 }
 
 func (c *Adapter) scpExec(args string, in io.Reader, out io.Writer) error {

adapter/scp.go

@@ -42,13 +42,13 @@ well.
 func scpUploadSession(opts []byte, rest string, in io.Reader, out io.Writer, comm packersdk.Communicator) error {
 	rest = strings.TrimSpace(rest)
 	if len(rest) == 0 {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return errors.New("no scp target specified")
 	}
 
 	d, err := tmp.Dir("ansible-upload")
 	if err != nil {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return err
 	}
 	defer os.RemoveAll(d)
@@ -60,41 +60,41 @@ func scpUploadSession(opts []byte, rest string, in io.Reader, out io.Writer, com
 	// irrelevant.
 	state := &scpUploadState{target: rest, srcRoot: d, comm: comm}
 
-	fmt.Fprintf(out, scpOK) // signal the client to start the transfer.
+	fmt.Fprint(out, scpOK) // signal the client to start the transfer.
 	return state.Protocol(bufio.NewReader(in), out)
 }
 
 func scpDownloadSession(opts []byte, rest string, in io.Reader, out io.Writer, comm packersdk.Communicator) error {
 	rest = strings.TrimSpace(rest)
 	if len(rest) == 0 {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return errors.New("no scp source specified")
 	}
 
 	d, err := tmp.Dir("ansible-download")
 	if err != nil {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return err
 	}
 	defer os.RemoveAll(d)
 
 	if bytes.Contains([]byte{'d'}, opts) {
 		// the only ansible module that supports downloading via scp is fetch,
 		// fetch only supports file downloads as of Ansible 2.1.
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return errors.New("directory downloads not supported")
 	}
 
 	f, err := os.Create(filepath.Join(d, filepath.Base(rest)))
 	if err != nil {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return err
 	}
 	defer f.Close()
 
 	err = comm.Download(rest, f)
 	if err != nil {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return err
 	}
 
@@ -118,7 +118,7 @@ func (state *scpDownloadState) FileProtocol(path string, info os.FileInfo, in *b
 	defer f.Close()
 
 	io.CopyN(out, f, size)
-	fmt.Fprintf(out, scpOK)
+	fmt.Fprint(out, scpOK)
 
 	return scpResponse(in)
 }
@@ -157,12 +157,12 @@ func (state *scpUploadState) Protocol(in *bufio.Reader, out io.Writer) error {
 			return state.FileProtocol(in, out)
 		case 'E':
 			state.dir = filepath.Dir(state.dir)
-			fmt.Fprintf(out, scpOK)
+			fmt.Fprint(out, scpOK)
 			return nil
 		case 'D':
 			return state.DirProtocol(in, out)
 		default:
-			fmt.Fprintf(out, scpEmptyError)
+			fmt.Fprint(out, scpEmptyError)
 			return fmt.Errorf("unexpected message: %c", b)
 		}
 	}
@@ -178,10 +178,10 @@ func (state *scpUploadState) FileProtocol(in *bufio.Reader, out io.Writer) error
 	var name string
 	_, err := fmt.Fscanf(in, "%04o %d %s\n", &mode, &size, &name)
 	if err != nil {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return fmt.Errorf("invalid file message: %v", err)
 	}
-	fmt.Fprintf(out, scpOK)
+	fmt.Fprint(out, scpOK)
 
 	var fi os.FileInfo = fileInfo{name: name, size: size, mode: mode, mtime: state.mtime}
 
@@ -192,25 +192,25 @@ func (state *scpUploadState) FileProtocol(in *bufio.Reader, out io.Writer) error
 
 	err = state.comm.Upload(dest, io.LimitReader(in, fi.Size()), &fi)
 	if err != nil {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return err
 	}
 
 	if err := scpResponse(in); err != nil {
 		return err
 	}
 
-	fmt.Fprintf(out, scpOK)
+	fmt.Fprint(out, scpOK)
 	return nil
 }
 
 func (state *scpUploadState) TimeProtocol(in *bufio.Reader, out io.Writer) error {
 	var m, a int64
 	if _, err := fmt.Fscanf(in, "%d 0 %d 0\n", &m, &a); err != nil {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return err
 	}
-	fmt.Fprintf(out, scpOK)
+	fmt.Fprint(out, scpOK)
 
 	state.atime = time.Unix(a, 0)
 	state.mtime = time.Unix(m, 0)
@@ -223,10 +223,10 @@ func (state *scpUploadState) DirProtocol(in *bufio.Reader, out io.Writer) error
 	var name string
 
 	if _, err := fmt.Fscanf(in, "%04o %d %s\n", &mode, &length, &name); err != nil {
-		fmt.Fprintf(out, scpEmptyError)
+		fmt.Fprint(out, scpEmptyError)
 		return fmt.Errorf("invalid directory message: %v", err)
 	}
-	fmt.Fprintf(out, scpOK)
+	fmt.Fprint(out, scpOK)
 
 	path := filepath.Join(state.dir, name)
 	if err := os.Mkdir(path, mode); err != nil {

chroot/communicator_test.go

@@ -12,6 +12,7 @@ import (
 func TestCommunicator_ImplementsCommunicator(t *testing.T) {
 	var raw interface{}
 	raw = &Communicator{}
+
 	if _, ok := raw.(packersdk.Communicator); !ok {
 		t.Fatalf("Communicator should be a communicator")
 	}

communicator/config.go

@@ -627,7 +627,7 @@ func (c *Config) prepareWinRM(ctx *interpolate.Context) (errs []error) {
 		c.WinRMTimeout = 30 * time.Minute
 	}
 
-	if c.WinRMUseNTLM == true {
+	if c.WinRMUseNTLM {
 		c.WinRMTransportDecorator = func() winrm.Transporter { return &winrm.ClientNTLM{} }
 	}
 

multistep/commonsteps/iso_config_test.go

@@ -23,34 +23,6 @@ func testISOConfig() ISOConfig {
 	}
 }
 
-var cs_bsd_style = `
-MD5 (other.iso) = bAr
-MD5 (the-OS.iso) = baZ
-`
-
-var cs_bsd_style_subdir = `
-MD5 (other.iso) = bAr
-MD5 (./subdir/the-OS.iso) = baZ
-`
-
-var cs_gnu_style = `
-bAr0 *the-OS.iso
-baZ0  other.iso
-`
-
-var cs_gnu_style_subdir = `
-bAr0 *./subdir/the-OS.iso
-baZ0  other.iso
-`
-
-var cs_bsd_style_no_newline = `
-MD5 (other.iso) = bAr
-MD5 (the-OS.iso) = baZ`
-
-var cs_gnu_style_no_newline = `
-bAr0 *the-OS.iso
-baZ0  other.iso`
-
 func TestISOConfigPrepare_ISOChecksum(t *testing.T) {
 	i := testISOConfig()
 
@@ -89,10 +61,8 @@ func TestISOConfigPrepare_ISOChecksumURLBad(t *testing.T) {
 }
 
 func TestISOConfigPrepare_ISOChecksumType(t *testing.T) {
-	i := testISOConfig()
-
 	// Test none
-	i = testISOConfig()
+	i := testISOConfig()
 	i.ISOChecksum = "none"
 	warns, err := i.Prepare(nil)
 	if len(warns) == 0 {

multistep/commonsteps/step_create_floppy.go

@@ -199,9 +199,7 @@ func (s *StepCreateFloppy) Run(ctx context.Context, state multistep.StateBag) mu
 				return multistep.ActionHalt
 			}
 
-			for _, filename := range matches {
-				pathqueue = append(pathqueue, filename)
-			}
+			pathqueue = append(pathqueue, matches...)
 			continue
 		}
 		pathqueue = append(pathqueue, filename)

multistep/commonsteps/step_create_floppy_test.go

@@ -248,7 +248,7 @@ func TestStepCreateFloppyDirectories(t *testing.T) {
 			for _, c := range test.dirs {
 				step.Directories = append(step.Directories, filepath.Join(dir, filepath.FromSlash(c)))
 			}
-			log.Println(fmt.Sprintf("Trying against floppy_dirs : %v", step.Directories))
+			log.Printf("Trying against floppy_dirs : %v\n", step.Directories)
 
 			// run the step
 			if action := step.Run(context.Background(), state); action != multistep.ActionContinue {

multistep/commonsteps/step_download.go

@@ -31,8 +31,9 @@ import (
 // progress reporting, interrupt handling, etc.
 //
 // Uses:
-//   cache packer.Cache
-//   ui    packersdk.Ui
+//
+//	cache packer.Cache
+//	ui    packersdk.Ui
 type StepDownload struct {
 	// The checksum and the type of the checksum for the download
 	Checksum string
@@ -124,7 +125,7 @@ func (s *StepDownload) Run(ctx context.Context, state multistep.StateBag) multis
 			// TODO(adrien): make go-getter allow using files in place.
 			// ovf files usually point to a file in the same directory, so
 			// using them in place is the only way.
-			ui.Say(fmt.Sprintf("Using ovf inplace"))
+			ui.Say("Using ovf inplace")
 			dst = source
 		} else {
 			dst, err = s.download(ctx, ui, source)

multistep/commonsteps/step_provision.go

@@ -107,7 +107,7 @@ func (s *StepProvision) runWithHook(ctx context.Context, state multistep.StateBa
 	if comm == nil {
 		raw, ok := state.Get("communicator").(packersdk.Communicator)
 		if ok {
-			comm = raw.(packersdk.Communicator)
+			comm = raw
 		}
 	}
 

multistep/if.go

@@ -5,7 +5,7 @@ package multistep
 
 // if returns step only if on is true.
 func If(on bool, step Step) Step {
-	if on == false {
+	if !on {
 		return &nullStep{}
 	}
 	return step

packer/logs.go

@@ -50,15 +50,6 @@ func (l *secretFilter) FilterString(message string) string {
 	return message
 }
 
-func (l *secretFilter) get() (s []string) {
-	l.m.Lock()
-	defer l.m.Unlock()
-	for k := range l.s {
-		s = append(s, k)
-	}
-	return
-}
-
 var LogSecretFilter secretFilter
 
 func init() {

rpc/server.go

@@ -14,16 +14,16 @@ import (
 
 const (
 	DefaultArtifactEndpoint      string = "Artifact"
-	DefaultBuildEndpoint                = "Build"
-	DefaultBuilderEndpoint              = "Builder"
-	DefaultCacheEndpoint                = "Cache"
-	DefaultCommandEndpoint              = "Command"
-	DefaultCommunicatorEndpoint         = "Communicator"
-	DefaultHookEndpoint                 = "Hook"
-	DefaultPostProcessorEndpoint        = "PostProcessor"
-	DefaultProvisionerEndpoint          = "Provisioner"
-	DefaultDatasourceEndpoint           = "Datasource"
-	DefaultUiEndpoint                   = "Ui"
+	DefaultBuildEndpoint         string = "Build"
+	DefaultBuilderEndpoint       string = "Builder"
+	DefaultCacheEndpoint         string = "Cache"
+	DefaultCommandEndpoint       string = "Command"
+	DefaultCommunicatorEndpoint  string = "Communicator"
+	DefaultHookEndpoint          string = "Hook"
+	DefaultPostProcessorEndpoint string = "PostProcessor"
+	DefaultProvisionerEndpoint   string = "Provisioner"
+	DefaultDatasourceEndpoint    string = "Datasource"
+	DefaultUiEndpoint            string = "Ui"
 )
 
 // PluginServer represents an RPC server for Packer. This must be paired on the

rpc/ui_progress_tracking.go

@@ -85,7 +85,7 @@ type ProgressTrackingServer struct {
 }
 
 func (t *ProgressTrackingServer) Add(size int, _ *interface{}) error {
-	stubBytes := make([]byte, size, size)
+	stubBytes := make([]byte, size)
 	t.stream.Read(stubBytes)
 	return nil
 }

sdk-internals/communicator/ssh/communicator.go

@@ -161,9 +161,9 @@ func (c *comm) Start(ctx context.Context, cmd *packersdk.RemoteCmd) (err error)
 		err := session.Wait()
 		exitStatus := 0
 		if err != nil {
-			switch err.(type) {
+			switch err := err.(type) {
 			case *ssh.ExitError:
-				exitStatus = err.(*ssh.ExitError).ExitStatus()
+				exitStatus = err.ExitStatus()
 				log.Printf("[ERROR] Remote command exited with '%d': %s", exitStatus, cmd.Command)
 			case *ssh.ExitMissingError:
 				log.Printf("[ERROR] Remote command exited without exit status or exit signal.")
@@ -490,7 +490,6 @@ func (c *comm) connectToAgent() {
 	}
 
 	log.Printf("[INFO] agent forwarding enabled")
-	return
 }
 
 func (c *comm) sftpUploadSession(path string, input io.Reader, fi *os.FileInfo) error {

sdk-internals/communicator/winrm/communicator.go

@@ -207,8 +207,7 @@ func (c *Communicator) newWinRMClient() (*winrm.Client, error) {
 	// winrmcp uses even we we aren't using winrmcp. This ensures similar
 	// behavior between upload, download, and copy functions. We can't use the
 	// one generated by winrmcp because it isn't exported.
-	var endpoint *winrm.Endpoint
-	endpoint = &winrm.Endpoint{
+	var endpoint = &winrm.Endpoint{
 		Host:          c.endpoint.Host,
 		Port:          c.endpoint.Port,
 		HTTPS:         conf.Https,