util.datamapper: Deal with locally built stanzas missing xmlns So the problem is that xmlns is not inherited when building a stanza, and then :get_child(n, ns) with an explicit namespace does not find that such child tags. E.g. local t = st.stanza("foo", { xmlns = "urn:example:bar" }) :text_tag("hello", "world"); assert(t:get_child("hello", "urn:example:bar"), "This fails"); Meanwhile, during parsing (util.xmppstream or util.xml) child tags do get the parents xmlns when not overriding them. Thus, in the above example, if the stanza is passed trough `t = util.xml.parse(tostring(t))` then the assert succeeds. This change makes it so that it leaves out the namespace argument to :get_child when it is the same as the current/parent namespace, which behaves the same for both built and parsed stanzas.

author: Kim Alvefur <zash@zash.se>
date: Tue, 23 Mar 2021 19:52:59 +0100
parent: 11475:9bd36e871f05
child: 11479:377a9eaf7bef
--- a/util/datamapper.lua	Mon Mar 22 22:24:39 2021 +0100
+++ b/util/datamapper.lua	Tue Mar 23 19:52:59 2021 +0100
@@ -29,7 +29,7 @@
 	local proptype = "string"
 	local value_where = propname and "in_text_tag" or "in_text"
 	local name = propname
-	local namespace = current_ns
+	local namespace
 	local prefix
 	local single_attribute
 	local enums
@@ -50,7 +50,7 @@
 			if xml.name then
 				name = xml.name
 			end
-			if xml.namespace then
+			if xml.namespace and xml.namespace ~= current_ns then
 				namespace = xml.namespace
 			end
 			if xml.prefix then
@@ -105,7 +105,7 @@
 		local attr = name
 		if prefix then
 			attr = prefix .. ":" .. name
-		elseif namespace ~= s.attr.xmlns then
+		elseif namespace and namespace ~= s.attr.xmlns then
 			attr = namespace .. "\1" .. name
 		end
 		return s.attr[attr]
@@ -218,7 +218,7 @@
 		local attr = name
 		if prefix then
 			attr = prefix .. ":" .. name
-		elseif namespace ~= current_ns then
+		elseif namespace and namespace ~= current_ns then
 			attr = namespace .. "\1" .. name
 		end
 
@@ -229,7 +229,7 @@
 		assert(single_attribute)
 		local propattr = {}
 
-		if namespace ~= current_ns then
+		if namespace and namespace ~= current_ns then
 			propattr.xmlns = namespace
 		end