util.stanza: Add an is_stanza() function to check if an object is a stanza

1 files changed, 6 insertions, 0 deletions

diff --git a/util/stanza.lua b/util/stanza.lua
index 8bb9ba05..2191fa8e 100644
--- a/util/stanza.lua
+++ b/util/stanza.lua
@@ -14,6 +14,7 @@ local s_format      = string.format;
 local s_match       =  string.match;
 local tostring      =      tostring;
 local setmetatable  =  setmetatable;
+local getmetatable  =  getmetatable;
 local pairs         =         pairs;
 local ipairs        =        ipairs;
 local type          =          type;
@@ -45,6 +46,10 @@ local function new_stanza(name, attr)
 	return setmetatable(stanza, stanza_mt);
 end
 
+local function is_stanza(s)
+	return getmetatable(s) == stanza_mt;
+end
+
 function stanza_mt:query(xmlns)
 	return self:tag("query", { xmlns = xmlns });
 end
@@ -417,6 +422,7 @@ end
 return {
 	stanza_mt = stanza_mt;
 	stanza = new_stanza;
+	is_stanza = is_stanza;
 	new_id = new_id;
 	preserialize = preserialize;
 	deserialize = deserialize;