Correctly parsing attribute selectors of the form '[attr]'.

document_parser.cpp

@@ -399,7 +399,8 @@ namespace Sass {
     lex< exactly<'['> >();
     if (!lex< type_selector >()) syntax_error("invalid attribute name in attribute selector");
     Token name(lexed);
-    attr_sel << Node(Node::value, line_number, lexed);
+    attr_sel << Node(Node::value, line_number, name);
+    if (lex< exactly<']'> >()) return attr_sel;
     if (!lex< alternatives< exact_match, class_match, dash_match,
                             prefix_match, suffix_match, substring_match > >()) {
       syntax_error("invalid operator in attribute selector for " + name.to_string());

node.cpp

@@ -125,7 +125,7 @@ namespace Sass {
         string result(prefix);
         if (!prefix.empty()) result += " ";
         result += "[";
-        for (int i = 0; i < 3; ++i)
+        for (int i = 0; i < size(); ++i)
         { result += at(i).to_string(prefix); }
         result += ']';
         return result;