archiver: Add filepath to error message if it is not included yet

internal/archiver/archiver.go

@@ -7,6 +7,7 @@ import (
 	"path"
 	"runtime"
 	"sort"
+	"strings"
 	"time"
 
 	"github.com/restic/restic/internal/debug"
@@ -169,6 +170,11 @@ func (arch *Archiver) error(item string, err error) error {
 		return err
 	}
 
+	// not all errors include the filepath, thus add it if it is missing
+	if !strings.Contains(err.Error(), item) {
+		err = fmt.Errorf("%v: %w", item, err)
+	}
+
 	errf := arch.Error(item, err)
 	if err != errf {
 		debug.Log("item %v: error was filtered by handler, before: %q, after: %v", item, err, errf)