Error widths now work properly

file/location.go

@@ -34,6 +34,11 @@ func (location Location) Width () (width int) {
 	return location.width
 }
 
+// SetWidth sets the location's width
+func (location *Location) SetWidth (width int) {
+	location.width = width
+}
+
 // Describe generates a description of the location for debug purposes
 func (location Location) Describe () (description string) {
 	return fmt.Sprint (

infoerr/error.go

@@ -67,7 +67,7 @@ func (err Error) Error () (formattedMessage string) {
 		}
 		
 		// print an arrow with a tail spanning the width of the mistake
-		for err.Width() > 1 {
+		for index < err.Column() + err.Width() - 1 {
 			if line[index] == '\t' {
 				formattedMessage += "--------"
 			} else {

lexer/lexer_test.go

@@ -242,6 +242,6 @@ func TestTokenizeErr (test *testing.T) {
 		"../tests/lexer/error/unknownEscape.arf",
 		infoerr.ErrorKindError,
 		"unknown escape character g",
-		1, 2, 1,
+		1, 1, 7,
 		test)
 }

lexer/text.go

@@ -9,9 +9,9 @@ func (lexer *LexingOperation) tokenizeString (isRuneLiteral bool) (err error) {
 	if err != nil { return }
 
 	token := lexer.newToken()
-
 	got := ""
 
+	beginning := lexer.file.Location(1)
 	for {
 		// TODO: add hexadecimal escape codes
 		if lexer.char == '\\' {
@@ -40,10 +40,11 @@ func (lexer *LexingOperation) tokenizeString (isRuneLiteral bool) (err error) {
 	err = lexer.nextRune()
 	if err != nil { return }
 
+	beginning.SetWidth(len(got))
 	if isRuneLiteral {
 		if len(got) > 1 {
 			err = infoerr.NewError (
-				lexer.file.Location(1),
+				beginning,
 				"excess data in rune literal",
 				infoerr.ErrorKindError)
 			return