lint: fix errorlint issues

5 files changed, 13 insertions, 10 deletions

diff --git a/internal/httprange/http_ranged_reader_test.go b/internal/httprange/http_ranged_reader_test.go
index d32e5619..22f2b094 100644
--- a/internal/httprange/http_ranged_reader_test.go
+++ b/internal/httprange/http_ranged_reader_test.go
@@ -2,6 +2,7 @@ package httprange
 
 import (
 	"context"
+	"errors"
 	"io"
 	"net/http"
 	"net/http/httptest"
@@ -95,7 +96,7 @@ func TestSectionReader(t *testing.T) {
 
 			buf := make([]byte, tt.readSize)
 			n, err := s.Read(buf)
-			if tt.expectedErr != nil && err != io.EOF {
+			if tt.expectedErr != nil && !errors.Is(err, io.EOF) {
 				require.EqualError(t, err, tt.expectedErr.Error())
 				return
 			}
diff --git a/internal/httprange/http_reader.go b/internal/httprange/http_reader.go
index c2b81b4d..639d391f 100644
--- a/internal/httprange/http_reader.go
+++ b/internal/httprange/http_reader.go
@@ -171,7 +171,7 @@ func (r *Reader) Read(buf []byte) (int, error) {
 	}
 
 	n, err := r.res.Body.Read(buf)
-	if err == nil || err == io.EOF {
+	if err == nil || errors.Is(err, io.EOF) {
 		r.offset += int64(n)
 	}
 
diff --git a/internal/serving/disk/reader.go b/internal/serving/disk/reader.go
index 5961d843..4078d5ef 100644
--- a/internal/serving/disk/reader.go
+++ b/internal/serving/disk/reader.go
@@ -50,7 +50,7 @@ func (reader *Reader) tryRedirects(h serving.Handler) bool {
 
 	rewrittenURL, status, err := r.Rewrite(h.Request.URL)
 	if err != nil {
-		if err != redirects.ErrNoRedirect {
+		if !errors.Is(err, redirects.ErrNoRedirect) {
 			// We assume that rewrite failure is not fatal
 			// and we only capture the error
 			errortracking.Capture(err, errortracking.WithRequest(h.Request), errortracking.WithStackTrace())
@@ -81,7 +81,8 @@ func (reader *Reader) tryFile(h serving.Handler) bool {
 	request := h.Request
 	urlPath := request.URL.Path
 
-	if locationError, _ := err.(*locationDirectoryError); locationError != nil {
+	var locationDirError *locationDirectoryError
+	if errors.As(err, &locationDirError) {
 		if endsWithSlash(urlPath) {
 			fullPath, err = reader.resolvePath(ctx, root, h.SubPath, "index.html")
 		} else {
@@ -90,7 +91,8 @@ func (reader *Reader) tryFile(h serving.Handler) bool {
 		}
 	}
 
-	if locationError, _ := err.(*locationFileNoExtensionError); locationError != nil {
+	var locationFileError *locationFileNoExtensionError
+	if errors.As(err, &locationFileError) {
 		fullPath, err = reader.resolvePath(ctx, root, strings.TrimSuffix(h.SubPath, "/")+".html")
 	}
 
diff --git a/internal/vfs/zip/archive.go b/internal/vfs/zip/archive.go
index b773899c..c44f45ef 100644
--- a/internal/vfs/zip/archive.go
+++ b/internal/vfs/zip/archive.go
@@ -100,10 +100,9 @@ func (a *zipArchive) openArchive(parentCtx context.Context, url string) (err err
 		return a.err
 	case <-ctx.Done():
 		err := ctx.Err()
-		switch err {
-		case context.Canceled:
+		if errors.Is(err, context.Canceled) {
 			log.ContextLogger(parentCtx).WithError(err).Traceln("open zip archive request canceled")
-		case context.DeadlineExceeded:
+		} else if errors.Is(err, context.DeadlineExceeded) {
 			log.ContextLogger(parentCtx).WithError(err).Traceln("open zip archive timed out")
 		}
 
@@ -264,7 +263,7 @@ func (a *zipArchive) Readlink(ctx context.Context, name string) (string, error)
 
 		// read up to len(symlink) bytes from the link file
 		n, err := io.ReadFull(rc, link[:])
-		if err != nil && err != io.ErrUnexpectedEOF {
+		if err != nil && !errors.Is(err, io.ErrUnexpectedEOF) {
 			// if err == io.ErrUnexpectedEOF the link is smaller than len(symlink) so it's OK to not return it
 			return nil, err
 		}
diff --git a/internal/vfs/zip/vfs_test.go b/internal/vfs/zip/vfs_test.go
index 98660719..4de0240a 100644
--- a/internal/vfs/zip/vfs_test.go
+++ b/internal/vfs/zip/vfs_test.go
@@ -2,6 +2,7 @@ package zip
 
 import (
 	"context"
+	"errors"
 	"io"
 	"io/fs"
 	"testing"
@@ -103,7 +104,7 @@ func TestVFSFindOrOpenArchiveConcurrentAccess(t *testing.T) {
 
 	require.Eventually(t, func() bool {
 		_, err := vfs.findOrOpenArchive(context.Background(), key, path)
-		return err == errAlreadyCached
+		return errors.Is(err, errAlreadyCached)
 	}, 3*time.Second, time.Nanosecond)
 }