Don't expose io.EOF in multifilereader

multifilereader.go

@@ -70,7 +70,7 @@ func (mfr *MultiFileReader) Read(buf []byte) (written int, err error) {
 
 			if !mfr.files[len(mfr.files)-1].Next() {
 				if mfr.files[len(mfr.files)-1].Err() != nil {
-					return 0, err
+					return 0, mfr.files[len(mfr.files)-1].Err()
 				}
 				mfr.files = mfr.files[:len(mfr.files)-1]
 				mfr.path = mfr.path[:len(mfr.path)-1]

multifilereader_test.go

@@ -61,16 +61,20 @@ func TestMultiFileReaderToMultiFile(t *testing.T) {
 		t.Fatal("iterator didn't work as expected")
 	}
 
-	if subIt.Next() {
+	if subIt.Next() || it.Err() != nil {
 		t.Fatal("iterator didn't work as expected")
 	}
 
 	// try to break internal state
-	if subIt.Next() {
+	if subIt.Next() || it.Err() != nil {
 		t.Fatal("iterator didn't work as expected")
 	}
 
-	if !it.Next() || it.Name() != "beep.txt" || it.Dir() != nil {
+	if !it.Next() || it.Name() != "beep.txt" || it.Dir() != nil || it.Err() != nil {
+		t.Fatal("iterator didn't work as expected")
+	}
+
+	if it.Next() || it.Err() != nil {
 		t.Fatal("iterator didn't work as expected")
 	}
 }

multipartfile.go

@@ -2,6 +2,7 @@ package files
 
 import (
 	"errors"
+	"io"
 	"io/ioutil"
 	"mime"
 	"mime/multipart"
@@ -127,6 +128,9 @@ func (it *multipartIterator) Next() bool {
 	}
 	part, err := it.f.Reader.NextPart()
 	if err != nil {
+		if err == io.EOF {
+			return false
+		}
 		it.err = err
 		return false
 	}
@@ -198,7 +202,15 @@ func (pr *peekReader) NextPart() (*multipart.Part, error) {
 		return p, nil
 	}
 
-	return pr.r.NextPart()
+	if pr.r == nil {
+		return nil, io.EOF
+	}
+
+	p, err := pr.r.NextPart()
+	if err == io.EOF {
+		pr.r = nil
+	}
+	return p, err
 }
 
 func (pr *peekReader) put(p *multipart.Part) error {