sorting preserves selection state

internal/files/disk.go

@@ -1,6 +1,7 @@
 package files
 
 import (
+	"fmt"
 	"io/fs"
 	"os"
 	"path/filepath"
@@ -31,6 +32,10 @@ func (f DiskFile) Filesize() int64 {
 	return f.filesize
 }
 
+func (f DiskFile) String() string {
+	return fmt.Sprintf(string_format, f.name, f.path, f.modified.Format(time.UnixDate), f.filesize, f.isdir)
+}
+
 func NewDisk(path string) (DiskFile, error) {
 	info, err := os.Stat(path)
 	if err != nil {

internal/files/files.go

@@ -6,12 +6,15 @@ import (
 	"time"
 )
 
+const string_format = "%s %s %s %d %t"
+
 type File interface {
 	Name() string
 	Path() string
 	Date() time.Time
 	Filesize() int64
 	IsDir() bool
+	String() string
 }
 
 type Files []File

internal/files/trash.go

@@ -54,6 +54,10 @@ func (t TrashInfo) Filesize() int64 {
 	return t.filesize
 }
 
+func (t TrashInfo) String() string {
+	return fmt.Sprintf(string_format, t.name, t.path, t.trashed.Format(time.UnixDate), t.filesize, t.isdir)
+}
+
 func FindTrash(trashdir, ogdir string, f *filter.Filter) (files Files, outerr error) {
 	outerr = filepath.WalkDir(trashdir, func(path string, d fs.DirEntry, err error) error {
 		if err != nil {