basic: refactor error handling

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

basic/error.go

@@ -10,24 +10,22 @@ var (
 	errInvalidToken = errors.New("invalid token")
 )
 
-func newErrInvalidToken(t *token) *lexer.Error {
-	err := &lexer.Error{
-		Line:    t.pos.Line,
-		Column:  t.pos.Column,
-		Content: t.value,
-		Err:     errInvalidToken,
-	}
-	return err
-}
-
-func (dec *decoder) OnError(pos lexer.Position, content string, err error) error {
-	err = &lexer.Error{
+func newError(pos lexer.Position, content, hint string, err error) *lexer.Error {
+	return &lexer.Error{
 		Line:    pos.Line,
 		Column:  pos.Column,
 		Content: content,
+		Hint:    hint,
 		Err:     err,
 	}
+}
 
+func newErrInvalidToken(t *token) *lexer.Error {
+	return newError(t.pos, t.value, "", errInvalidToken)
+}
+
+func (dec *decoder) OnError(pos lexer.Position, content string, err error) error {
+	err = newError(pos, content, "", err)
 	dec.executeFinal()
 	return err
 }

basic/token.go

@@ -29,7 +29,7 @@ func (dec *decoder) executeFinal() {
 	}
 }
 
-func (dec *decoder) execute(typ parser.TokenType) {
+func (dec *decoder) execute(typ parser.TokenType) error {
 	switch typ {
 	case parser.TokenSectionEnd:
 		name1, ok1 := dec.getValue(1, parser.TokenSectionName)
@@ -48,6 +48,8 @@ func (dec *decoder) execute(typ parser.TokenType) {
 		dec.addField(key, value)
 		dec.reset()
 	}
+
+	return nil
 }
 
 func (dec *decoder) addSection(key, id string, allowEmptyID bool) {
@@ -136,19 +138,25 @@ func (dec *decoder) typeOK(typ parser.TokenType) bool {
 }
 
 func (dec *decoder) OnToken(pos lexer.Position, typ parser.TokenType, value string) error {
+	var err error
 	t := &token{pos, typ, value}
 
 	switch {
 	case typ == parser.TokenComment:
 		// ignore comments
-		return nil
 	case dec.typeOK(typ):
 		// acceptable token
 		dec.queue = append(dec.queue, t)
-		dec.execute(typ)
-		return nil
+		err = dec.execute(typ)
 	default:
 		// unacceptable
-		return newErrInvalidToken(t)
+		err = newErrInvalidToken(t)
 	}
+
+	if err != nil {
+		dec.executeFinal()
+		return err
+	}
+
+	return nil
 }