fix!: query escape abspath header

CHANGELOG.md

@@ -22,6 +22,11 @@ The following emojis are used to highlight certain changes:
 
 ### Fixed
 
+* 🛠 `MultiFileReader` has been updated to escape the absolute paths due to the regression
+  found in [`net/textproto`](https://github.com/golang/go/issues/60674). This is no longer
+  compatible with previous versions when using files that have binary characters in their
+  name.
+
 ### Security
 
 ## [v0.11.0]

files/multifilereader.go

@@ -114,7 +114,7 @@ func (mfr *MultiFileReader) Read(buf []byte) (written int, err error) {
 
 			header.Set("Content-Type", contentType)
 			if rf, ok := entry.Node().(FileInfo); ok {
-				header.Set("abspath", rf.AbsPath())
+				header.Set("abspath", url.QueryEscape(rf.AbsPath()))
 			}
 
 			_, err := mfr.mpWriter.CreatePart(header)

files/multipartfile.go

@@ -100,9 +100,14 @@ func (w *multipartWalker) nextFile() (Node, error) {
 
 		return NewLinkFile(string(out), nil), nil
 	default:
+		abspath, err := url.QueryUnescape(part.Header.Get("abspath"))
+		if err != nil {
+			return nil, err
+		}
+
 		return &ReaderFile{
 			reader:  part,
-			abspath: part.Header.Get("abspath"),
+			abspath: abspath,
 		}, nil
 	}
 }