Merge pull request #1 from ernesto-jimenez/allow-custom-line-ending

Configurable line ends

encode.go

@@ -58,12 +58,15 @@ func (e *MarshalInvalidTypeError) Error() string {
 // stream.
 type Encoder struct {
 	w *bufio.Writer
+
+	LineEnd []byte
 }
 
 // NewEncoder returns a new encoder that writes to w.
 func NewEncoder(w io.Writer) *Encoder {
 	return &Encoder{
-		bufio.NewWriter(w),
+		w:       bufio.NewWriter(w),
+		LineEnd: []byte("\n"),
 	}
 }
 
@@ -95,14 +98,18 @@ func (e *Encoder) Encode(i interface{}) (err error) {
 }
 
 func (e *Encoder) writeLines(v reflect.Value) error {
+	lineEnd := e.LineEnd
+	if len(lineEnd) == 0 {
+		lineEnd = []byte("\n")
+	}
 	for i := 0; i < v.Len(); i++ {
 		err := e.writeLine(v.Index(i))
 		if err != nil {
 			return err
 		}
 
 		if i != v.Len()-1 {
-			_, err := e.w.Write([]byte("\n"))
+			_, err := e.w.Write(lineEnd)
 			if err != nil {
 				return err
 			}

encode_test.go

@@ -3,10 +3,12 @@ package fixedwidth
 import (
 	"bytes"
 	"fmt"
-	"github.com/pkg/errors"
+	"io"
 	"log"
 	"reflect"
 	"testing"
+
+	"github.com/pkg/errors"
 )
 
 func ExampleMarshal() {
@@ -126,3 +128,35 @@ func TestNewValueEncoder(t *testing.T) {
 		})
 	}
 }
+
+func TestEncoderWithMultipleLines(t *testing.T) {
+	input := []interface{}{
+		EncodableString{"foo", nil},
+		EncodableString{"bar", nil},
+	}
+
+	for _, tt := range []struct {
+		name       string
+		expected   string
+		newEncoder func(io.Writer) *Encoder
+	}{
+		{"default", "foo\nbar", func(w io.Writer) *Encoder { return NewEncoder(w) }},
+		{"default", "foo\r\nbar", func(w io.Writer) *Encoder {
+			enc := NewEncoder(w)
+			enc.LineEnd = []byte("\r\n")
+			return enc
+		}},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			var buf bytes.Buffer
+			enc := tt.newEncoder(&buf)
+			err := enc.Encode(input)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if buf.String() != tt.expected {
+				t.Fatalf("unexpected output\nexpected: %q\nreceived: %q", tt.expected, buf.String())
+			}
+		})
+	}
+}