Bump libasciidoc dependency

hswg/main.go

@@ -107,7 +107,11 @@ func Render(r io.Reader, config configuration.Configuration) (
 
 	var doc types.Document
 	if doc, err = parser.ParseDocument(pr, config); err == nil {
-		for _, problem := range validator.Validate(&doc) {
+		problems, err := validator.Validate(&doc)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+		}
+		for _, problem := range problems {
 			fmt.Fprintln(os.Stderr, problem.Message)
 		}
 		ctx := renderer.NewContext(doc, config)
@@ -140,7 +144,7 @@ type Entry struct {
 
 // Published returns the date when the entry was published, or nil if unknown.
 func (e *Entry) Published() *time.Time {
-	if d, ok := e.Metadata.Attributes.GetAsString("date"); !ok {
+	if d, _, err := e.Metadata.Attributes.GetAsString("date"); err != nil {
 		return nil
 	} else if t, err := time.Parse(time.RFC3339, d); err == nil {
 		return &t