WIP: Line wrapping for text/plain content

encode.go

@@ -18,6 +18,9 @@ import (
 // from quoted-printable to base64 encoding.
 const b64Percent = 20
 
+// lineWrapLength is the length at which we wrap base64 and plain text content
+const lineWrapLength = 76
+
 type transferEncoding byte
 
 const (
@@ -159,25 +162,25 @@ func (p *Part) encodeContent(b *bufio.Writer, cte transferEncoding) (err error)
 		text := make([]byte, enc.EncodedLen(len(p.Content)))
 		base64.StdEncoding.Encode(text, p.Content)
 		// Wrap lines.
-		lineLen := 76
-		for len(text) > 0 {
-			if lineLen > len(text) {
-				lineLen = len(text)
-			}
-			if _, err = b.Write(text[:lineLen]); err != nil {
-				return err
-			}
-			b.Write(crnl)
-			text = text[lineLen:]
+		if err := wrapContent(text, b); err != nil {
+			return err
 		}
+		//b.Write(crnl)
 	case teQuoted:
 		qp := quotedprintable.NewWriter(b)
 		if _, err = qp.Write(p.Content); err != nil {
 			return err
 		}
 		err = qp.Close()
 	default:
-		_, err = b.Write(p.Content)
+		if p.ContentType == ctTextPlain {
+			// Wrap lines.
+			if err := wrapContent(p.Content, b); err != nil {
+				return err
+			}
+		} else {
+			_, err = b.Write(p.Content)
+		}
 	}
 	return err
 }
@@ -213,3 +216,22 @@ func setParamValue(p map[string]string, k, v string) {
 		p[k] = v
 	}
 }
+
+func wrapContent(text []byte, b *bufio.Writer) error {
+	lineLen := lineWrapLength
+	beginning := true
+	for len(text) > 0 {
+		if !beginning {
+			b.Write(crnl)
+		}
+		if lineLen > len(text) {
+			lineLen = len(text)
+		}
+		if _, err := b.Write(text[:lineLen]); err != nil {
+			return err
+		}
+		text = text[lineLen:]
+		beginning = false
+	}
+	return nil
+}

encode_test.go

@@ -77,7 +77,7 @@ func TestEncodePartBinaryHeader(t *testing.T) {
 		0xa2, 0xb2, 0xc0, 0x90, 0x59, 0xe3, 0x35, 0xf8, 0x60, 0xb7, 0xb1, 0x63, 0x77, 0xd7,
 		0x5f, 0x92, 0x58, 0xa8, 0x75,
 	}))
-	p.Content = []byte("This is a test of a plain text part.\r\n\r\nAnother line.\r\n")
+	p.Content = []byte("This is a test of a plain text part.\r\n\r\nAnother line.")
 
 	b := &bytes.Buffer{}
 	err := p.Encode(b)
@@ -101,7 +101,7 @@ func TestEncodePartContentOnly(t *testing.T) {
 
 func TestEncodePartPlain(t *testing.T) {
 	p := enmime.NewPart("text/plain")
-	p.Content = []byte("This is a test of a plain text part.\r\n\r\nAnother line.\r\n")
+	p.Content = []byte("This is a test of a plain text part.\r\n\r\nAnother line.")
 
 	b := &bytes.Buffer{}
 	err := p.Encode(b)

testdata/encode/part-bin-content.golden

@@ -36,4 +36,4 @@ rq+wsbKztLW2t7i5uru8vb6/wMHCw8TFxsfIycrLzM3Oz9DR0tPU1dbX2Nna29zd3t/g4eLj5OXm
 ICEiIyQlJicoKSorLC0uLzAxMjM0NTY3ODk6Ozw9Pj9AQUJDREVGR0hJSktMTU5PUFFSU1RVVldY
 WVpbXF1eX2BhYmNkZWZnaGlqa2xtbm9wcXJzdHV2d3h5ent8fX5/gIGCg4SFhoeIiYqLjI2Oj5CR
 kpOUlZaXmJmam5ydnp+goaKjpKWmp6ipqqusra6vsLGys7S1tre4ubq7vL2+v8DBwsPExcbHyMnK
-y8zNzs8=
+y8zNzs8=

testdata/encode/part-bin-header.golden

@@ -5,4 +5,4 @@ X-Data: =?utf-8?b?AxfhfujropadladnggnfjgwsaiubvnmkadiuhterqHJSFfuAjkfhrqpeorLA?=
 
 This is a test of a plain text part.
 
-Another line.
+Another line.

testdata/encode/part-default-headers.golden

@@ -5,4 +5,4 @@ Content-Transfer-Encoding: base64
 Content-Type: application/zip; boundary=enmime-abcdefg0123456789;
  charset=binary; name=stuff.zip
 
-WklQWklQWklQ
+WklQWklQWklQ

testdata/encode/part-plain.golden

@@ -2,4 +2,4 @@ Content-Type: text/plain; charset=utf-8
 
 This is a test of a plain text part.
 
-Another line.
+Another line.

testdata/encode/part-quoted-headers.golden

@@ -5,4 +5,4 @@ Content-Transfer-Encoding: base64
 Content-Type: application/zip; boundary=enmime-abcdefg0123456789;
  charset=binary; name="arvizturo \"x\" tukorfurogep.zip"
 
-WklQWklQWklQ
+WklQWklQWklQ