fix lint issues

cmd/main.go

@@ -33,7 +33,7 @@ func main() {
 	runtime.GOMAXPROCS(runtime.NumCPU())
 
 	meta.Version = version
-	meta.UserAgent = fmt.Sprintf("%s/%s go/%s %s", meta.ID, meta.Version, runtime.Version()[2:], strings.Title(runtime.GOOS))
+	meta.UserAgent = fmt.Sprintf("%s/%s go/%s %s", meta.ID, meta.Version, runtime.Version()[2:], strings.Title(runtime.GOOS)) //nolint:staticcheck // ignoring "SA1019: strings.Title is deprecated", as for our use we don't need full unicode support
 
 	_ = kong.Parse(&cli,
 		kong.Name(meta.ID),

internal/app/undock.go

@@ -9,7 +9,7 @@ import (
 	"github.com/crazy-max/undock/internal/config"
 	ximage "github.com/crazy-max/undock/pkg/extractor/image"
 	"github.com/crazy-max/undock/pkg/image"
-	specs "github.com/opencontainers/image-spec/specs-go/v1"
+	ocispecs "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/pkg/errors"
 )
 
@@ -18,7 +18,7 @@ type Undock struct {
 	ctx      context.Context
 	meta     config.Meta
 	cli      config.Cli
-	platform specs.Platform
+	platform ocispecs.Platform
 }
 
 // New creates new undock instance

pkg/extractor/blob.go

@@ -2,7 +2,6 @@ package extractor
 
 import (
 	"context"
-	"fmt"
 	"io"
 	"io/fs"
 	"os"
@@ -93,7 +92,7 @@ func ExtractBlob(filename string, dest string, opts ExtractBlobOpts) error {
 		case f.FileInfo.Mode()&fs.ModeSymlink != 0:
 			return writeSymlink(ctx, path, f)
 		default:
-			return fmt.Errorf("cannot handle file mode: %v", f.FileInfo.Mode())
+			return errors.Errorf("cannot handle file mode: %v", f.FileInfo.Mode())
 		}
 	})
 }

pkg/extractor/image/image.go

@@ -11,7 +11,7 @@ import (
 	"github.com/containerd/containerd/platforms"
 	"github.com/containers/image/v5/manifest"
 	"github.com/crazy-max/undock/pkg/extractor"
-	specs "github.com/opencontainers/image-spec/specs-go/v1"
+	ocispecs "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/pkg/errors"
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
@@ -31,7 +31,7 @@ type Options struct {
 	// Source image reference
 	Source string
 	// Platform to enforce for Source image
-	Platform specs.Platform
+	Platform ocispecs.Platform
 	// Includes a subset of files/dirs from the Source image
 	Includes []string
 	// All extracts all architectures if Source image is a manifest list
@@ -102,14 +102,14 @@ func (c *Client) Extract() error {
 	}
 
 	type manifestEntry struct {
-		platform specs.Platform
+		platform ocispecs.Platform
 		manifest *manifest.OCI1
 	}
 
 	var mans []manifestEntry
 
 	mtype := manifest.GuessMIMEType(manblob)
-	if mtype == specs.MediaTypeImageManifest {
+	if mtype == ocispecs.MediaTypeImageManifest {
 		man, err := manifest.OCI1FromManifest(manblob)
 		if err != nil {
 			return errors.Wrap(err, "cannot create OCI manifest instance from blob")
@@ -118,7 +118,7 @@ func (c *Client) Extract() error {
 			platform: c.opts.Platform,
 			manifest: man,
 		})
-	} else if mtype == specs.MediaTypeImageIndex {
+	} else if mtype == ocispecs.MediaTypeImageIndex {
 		ocindex, err := manifest.OCI1IndexFromManifest(manblob)
 		if err != nil {
 			return errors.Wrap(err, "cannot create OCI manifest index instance from blob")

pkg/image/ref.go

@@ -28,10 +28,8 @@ func Reference(name string) (reference.Named, error) {
 	ref, err := reference.ParseNormalizedNamed(name)
 	if err != nil {
 		return nil, errors.Wrapf(err, "parsing normalized named %q", name)
-	}
-
-	if _, ok := ref.(reference.Named); !ok {
-		return nil, fmt.Errorf("%q is not a named reference", name)
+	} else if ref == nil {
+		return nil, errors.Errorf("%q is not a named reference", name)
 	}
 
 	if _, hasTag := ref.(reference.NamedTagged); hasTag {