From fdbffe744b38811be8b1cf6a9eec3eea4d71c412 Mon Sep 17 00:00:00 2001
From: Sutou Kouhei <kou@clear-code.com>
Date: Sat, 17 Aug 2024 16:14:19 +0900
Subject: [PATCH] Use loop instead of recursive call for Element#namespace

It's for performance and avoiding stack level too deep.
---
 lib/rexml/element.rb | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/lib/rexml/element.rb b/lib/rexml/element.rb
index 27132926..eb802165 100644
--- a/lib/rexml/element.rb
+++ b/lib/rexml/element.rb
@@ -624,8 +624,12 @@ def namespace(prefix=nil)
       else
         prefix = "xmlns:#{prefix}" unless prefix[0,5] == 'xmlns'
       end
-      ns = attributes[ prefix ]
-      ns = parent.namespace(prefix) if ns.nil? and parent
+      ns = nil
+      target = self
+      while ns.nil? and target
+        ns = target.attributes[prefix]
+        target = target.parent
+      end
       ns = '' if ns.nil? and prefix == 'xmlns'
       return ns
     end