parser: use GetPositionalLength() on TextParser.Discard() and TextParser.Emit()

Signed-off-by: Alejandro Mery <amery@jpi.io>

parser/text.go

@@ -39,9 +39,10 @@ func (p *TextParser) InitString(s string) {
 
 // Discard shadows [lexer.Reader]'s, and takes in consideration
 // new lines on the discarded data when moving the position
-func (*TextParser) Discard() {
-	// TODO: consider new lines
-	panic("not implemented")
+func (p *TextParser) Discard() {
+	s := p.Reader.Emit()
+	l := GetPositionalLength(s)
+	p.pos.Add(l)
 }
 
 // Emit returns the accepted text, its position, and
@@ -49,8 +50,8 @@ func (*TextParser) Discard() {
 func (p *TextParser) Emit() (lexer.Position, string) {
 	pos := p.pos
 	s := p.Reader.Emit()
-	// TODO: consider new lines
-	p.pos.StepN(len(s))
+	l := GetPositionalLength(s)
+	p.pos.Add(l)
 
 	return pos, s
 }