add feature to have a multiple line with quote escaping

reader.go

@@ -198,13 +198,16 @@ func (r *Reader) readQuotedField() (string, error) {
 
 	s := &r.tmpBuf
 	defer r.tmpBuf.Reset() // TODO: Not using defer here is faster.
+	var previousChar rune
 	for {
 		char, _, err := r.r.ReadRune()
 		if err != nil {
 			return s.String(), err
 		}
-		if char != r.opts.QuoteChar {
-			s.WriteRune(char)
+		if char != r.opts.QuoteChar || previousChar == r.opts.EscapeChar {
+			if char != r.opts.EscapeChar {
+				s.WriteRune(char)
+			}
 		} else {
 			switch r.opts.DoubleQuote {
 			case DoDoubleQuote:
@@ -237,6 +240,7 @@ func (r *Reader) readQuotedField() (string, error) {
 				panic("Unrecognized double quote mode.")
 			}
 		}
+		previousChar = char
 	}
 
 	// Required by Go 1.0 to compile. Unreachable code.

reader_test.go

@@ -284,3 +284,18 @@ func TestReadingWithComments(t *testing.T) {
 		t.Error("Expected EOF, but got:", err)
 	}
 }
+
+func TestReadingMultipleLineWithQuoteEscaping(t *testing.T) {
+	t.Parallel()
+
+	b := new(bytes.Buffer)
+	// a,"b \"c d\ne\"", f
+	b.WriteString(`a,"b \"c d
+e\"",f` + "\n")
+	r := NewReader(b)
+
+	err := testReadingSingleLine(t, r, []string{"a", `b "c d` + "\n" + `e"`, "f"})
+	if err != nil && err != io.EOF {
+		t.Error("Unexpected error:", err)
+	}
+}