util.stanza: Serializer optimizations, and nicer output for empty elements

diff --git a/util/stanza.lua b/util/stanza.lua
index eb9f392209d78b6ea60c53f95def5026645bbbec..35d600ed4bc153b4b8e2e36eacb2a58c1b4e213a 100644 (file)
--- a/util/stanza.lua
+++ b/util/stanza.lua
@@ -24,6 +24,7 @@ local print         =         print;
 local unpack        =        unpack;
 local s_gsub        =   string.gsub;
 local s_char        =   string.char;
+local s_find        =   string.find;
 local os            =            os;
 
 local do_pretty_printing = not os.getenv("WINDIR");
@@ -122,27 +123,33 @@ local xml_escape = (function()
        return function(str) return (s_gsub(str, "['&<>\"]", escape_table)); end
 end)();
 local function _dostring(t, buf, self, xml_escape)
-       local nsid, ns, attrk = 0;
-       t_insert(buf, "<"..t.name);
+       local nsid = 0;
+       local name = t.name
+       t_insert(buf, "<"..name);
        for k, v in pairs(t.attr) do
-               ns, attrk = s_match(k, "^([^|]+)|(.+)$");
-               if ns then
+               if s_find(k, "|", 1, true) then
+                       local ns, attrk = s_match(k, "^([^|]+)|(.+)$");
                        nsid = nsid + 1;
                        t_insert(buf, " xmlns:ns"..nsid.."='"..xml_escape(ns).."' ".."ns"..nsid..":"..attrk.."='"..xml_escape(v).."'");
                else
                        t_insert(buf, " "..k.."='"..xml_escape(v).."'");
                end
        end
-       t_insert(buf, ">");
-       for n=1,#t do
-               local child = t[n];
-               if child.name then
-                       self(child, buf, self, xml_escape);
-               else
-                       t_insert(buf, xml_escape(child));
+       local len = #t;
+       if len == 0 then
+               t_insert(buf, "/>");
+       else
+               t_insert(buf, ">");
+               for n=1,len do
+                       local child = t[n];
+                       if child.name then
+                               self(child, buf, self, xml_escape);
+                       else
+                               t_insert(buf, xml_escape(child));
+                       end
                end
+               t_insert(buf, "</"..name..">");
        end
-       t_insert(buf, "</"..t.name..">");
 end
 function stanza_mt.__tostring(t)
        local buf = {};