# HG changeset patch
# User Kim Alvefur <zash@zash.se>
# Date 1681896773 -7200
# Node ID 6da83deb8d7f7a2921db69f06b8e50dabe3945e4
# Parent  de42a93a7c8d777ed871fd1305d3d1ea3c131a28
util.error: Fix error on conversion of invalid error stanza, fix #1805

Error stanzas should have an <error> element, but if you pass a
stanza without one to util.error.from_stanza() it triggers an attempt to
index a nil value, which this patch avoids.

In the conditional, it should be safe to assume error_tag is non-nil
since condition can't have those values then.

diff -r de42a93a7c8d -r 6da83deb8d7f util/error.lua
--- a/util/error.lua	Thu Apr 06 17:09:03 2023 +0200
+++ b/util/error.lua	Wed Apr 19 11:32:53 2023 +0200
@@ -141,7 +141,7 @@
 	local error_tag = stanza:get_child("error");
 	context = context or {};
 	context.stanza = stanza;
-	context.by = error_tag.attr.by or stanza.attr.from;
+	context.by = error_tag and error_tag.attr.by or stanza.attr.from;
 
 	local uri;
 	if condition == "gone" or condition == "redirect" then