From 7c5918c35f347446cd7db9804ca3a3caa1187a7d Mon Sep 17 00:00:00 2001
From: Leon Bogaert <leon@tim-online.nl>
Date: Tue, 10 Dec 2019 14:16:52 +0100
Subject: [PATCH] Implement suggest changes for decode lineTerminator

---
 decode.go      | 30 +++++++++++++-----------------
 decode_test.go | 30 +++++++++++++++---------------
 2 files changed, 28 insertions(+), 32 deletions(-)

diff --git a/decode.go b/decode.go
index 45eb695..f050d56 100644
--- a/decode.go
+++ b/decode.go
@@ -22,7 +22,7 @@ func Unmarshal(data []byte, v interface{}) error {
 // A Decoder reads and decodes fixed width data from an input stream.
 type Decoder struct {
 	scanner             *bufio.Scanner
-	separator           string
+	lineTerminator      []byte
 	done                bool
 	useCodepointIndices bool
 
@@ -33,10 +33,10 @@ type Decoder struct {
 // NewDecoder returns a new decoder that reads from r.
 func NewDecoder(r io.Reader) *Decoder {
 	dec := &Decoder{
-		scanner:   bufio.NewScanner(r),
-		separator: "",
+		scanner:        bufio.NewScanner(r),
+		lineTerminator: []byte("\n"),
 	}
-	dec.scanner.Split(dec.Scan)
+	dec.scanner.Split(dec.scan)
 	return dec
 }
 
@@ -182,26 +182,22 @@ func findFirstMultiByteChar(data string) int {
 	return len(data)
 }
 
-func (d *Decoder) SetSeparator(separator string) {
-	d.separator = separator
-}
-
-func (d Decoder) Separator() string {
-	if d.separator != "" {
-		return d.separator
+// SetLineTerminator sets the character(s) that will be used to terminate lines.
+//
+// The default value is "\n".
+func (d *Decoder) SetLineTerminator(lineTerminator []byte) {
+	if len(lineTerminator) > 0 {
+		d.lineTerminator = lineTerminator
 	}
-
-	return "\n"
 }
 
-func (d *Decoder) Scan(data []byte, atEOF bool) (advance int, token []byte, err error) {
-	sep := []byte(d.Separator())
+func (d *Decoder) scan(data []byte, atEOF bool) (advance int, token []byte, err error) {
 	if atEOF && len(data) == 0 {
 		return 0, nil, nil
 	}
-	if i := bytes.Index(data, sep); i >= 0 {
+	if i := bytes.Index(data, d.lineTerminator); i >= 0 {
 		// We have a full newline-terminated line.
-		return i + len(sep), data[0:i], nil
+		return i + len(d.lineTerminator), data[0:i], nil
 	}
 	// If we're at EOF, we have a final, non-terminated line. Return it.
 	if atEOF {
diff --git a/decode_test.go b/decode_test.go
index dad5812..1cdbed0 100644
--- a/decode_test.go
+++ b/decode_test.go
@@ -342,12 +342,12 @@ func TestLineSeparator(t *testing.T) {
 		TextUnmarshaler EncodableString `fixed:"16,20"`
 	}
 	for _, tt := range []struct {
-		name      string
-		rawValue  []byte
-		target    interface{}
-		expected  interface{}
-		shouldErr bool
-		separator string
+		name           string
+		rawValue       []byte
+		target         interface{}
+		expected       interface{}
+		shouldErr      bool
+		lineTerminator []byte
 	}{
 		{
 			name:     "CR line endings",
@@ -357,8 +357,8 @@ func TestLineSeparator(t *testing.T) {
 				{"foo", 123, 1.2, EncodableString{"bar", nil}},
 				{"bar", 321, 2.1, EncodableString{"foo", nil}},
 			},
-			shouldErr: false,
-			separator: "",
+			shouldErr:      false,
+			lineTerminator: []byte{},
 		},
 		{
 			name:     "CR line endings",
@@ -368,8 +368,8 @@ func TestLineSeparator(t *testing.T) {
 				{"f\ro", 123, 1.2, EncodableString{"bar", nil}},
 				{"bar", 321, 2.1, EncodableString{"foo", nil}},
 			},
-			shouldErr: false,
-			separator: "\n",
+			shouldErr:      false,
+			lineTerminator: []byte("\n"),
 		},
 		{
 			name:     "CRLF line endings",
@@ -379,8 +379,8 @@ func TestLineSeparator(t *testing.T) {
 				{"f\no", 123, 1.2, EncodableString{"bar", nil}},
 				{"bar", 321, 2.1, EncodableString{"foo", nil}},
 			},
-			shouldErr: false,
-			separator: "\r\n",
+			shouldErr:      false,
+			lineTerminator: []byte("\r\n"),
 		},
 		{
 			name:     "LF line endings",
@@ -390,13 +390,13 @@ func TestLineSeparator(t *testing.T) {
 				{"f\no", 123, 1.2, EncodableString{"bar", nil}},
 				{"bar", 321, 2.1, EncodableString{"foo", nil}},
 			},
-			shouldErr: false,
-			separator: "\r",
+			shouldErr:      false,
+			lineTerminator: []byte("\r"),
 		},
 	} {
 		t.Run(tt.name, func(t *testing.T) {
 			dec := NewDecoder(bytes.NewReader(tt.rawValue))
-			dec.SetSeparator(tt.separator)
+			dec.SetLineTerminator(tt.lineTerminator)
 			err := dec.Decode(tt.target)
 			if tt.shouldErr != (err != nil) {
 				t.Errorf("Unmarshal() err want %v, have %v (%v)", tt.shouldErr, err != nil, err)