Fix linter list and fix errors discovered by new staticcheck

deb/remote.go

@@ -540,12 +540,10 @@ func (repo *RemoteRepo) DownloadPackageIndexes(progress aptly.Progress, d aptly.
 				}
 			}
 			err = repo.packageList.Add(p)
-			if err != nil {
-				if _, ok := err.(*PackageConflictError); ok {
-					progress.ColoredPrintf("@y[!]@| @!skipping package %s: duplicate in packages index@|", p)
-				} else {
-					return err
-				}
+			if _, ok := err.(*PackageConflictError); ok {
+				progress.ColoredPrintf("@y[!]@| @!skipping package %s: duplicate in packages index@|", p)
+			} else if err != nil {
+				return err
 			}
 		}
 

deb/version_test.go

@@ -5,7 +5,6 @@ import (
 )
 
 type VersionSuite struct {
-	stanza Stanza
 }
 
 var _ = Suite(&VersionSuite{})

http/download.go

@@ -81,7 +81,7 @@ func (downloader *downloaderImpl) GetLength(ctx context.Context, url string) (in
 	}
 
 	if resp.ContentLength < 0 {
-		return -1, fmt.Errorf("Could not determine length of %s", url)
+		return -1, fmt.Errorf("could not determine length of %s", url)
 	}
 
 	return resp.ContentLength, nil
@@ -94,12 +94,12 @@ func (downloader *downloaderImpl) Download(ctx context.Context, url string, dest
 
 func retryableError(err error) bool {
 	switch err.(type) {
-	case net.Error:
-		return true
 	case *net.OpError:
 		return true
 	case syscall.Errno:
 		return true
+	case net.Error:
+		return true
 	}
 	return false
 }

linter.json

@@ -7,7 +7,6 @@
         "deadcode",
         "goimports",
         "misspell",
-        "gosimple",
         "ineffassign",
         "staticcheck",
         "varcheck",

pgp/gnupg_test.go

@@ -10,8 +10,7 @@ import (
 )
 
 type GnupgSuite struct {
-	verifier Verifier
-	bins     string
+	bins string
 }
 
 var _ = Suite(&GnupgSuite{})

query/lex.go

@@ -119,14 +119,6 @@ func (l *lexer) backup() {
 	l.pos -= l.width
 }
 
-// peek returns but does not consume
-// the next rune in the input.
-func (l *lexer) peek() rune {
-	r := l.next()
-	l.backup()
-	return r
-}
-
 func (l *lexer) Current() item {
 	if l.last.typ == 0 {
 		l.last = <-l.items

s3/server_test.go

@@ -73,7 +73,6 @@ type Server struct {
 type bucket struct {
 	name    string
 	acl     string
-	ctime   time.Time
 	objects map[string]*object
 }
 

utils/utils.go

@@ -13,7 +13,7 @@ func DirIsAccessible(filename string) error {
 	_, err := os.Stat(filename)
 	if err != nil {
 		if !os.IsNotExist(err) {
-			return fmt.Errorf("Something went wrong, %v", err)
+			return fmt.Errorf("error checking directory '%s': %s", filename, err)
 		}
 	} else {
 		if unix.Access(filename, unix.W_OK) != nil {