From 437c018aaa1fbf6f71e439a451de41ab3907a3d9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Trung=20L=C3=AA?= <8@tle.id.au>
Date: Sun, 8 Feb 2026 02:39:12 +1100
Subject: [PATCH] Localize release note links on non-English releases pages

The releases pages for non-English languages (ja, ko, uk, vi, zh_cn)
always linked to the English (/en/) release posts because the post URL
in _data/releases.yml is hardcoded to /en/.

Add a localize_post_url Liquid filter plugin that checks whether a
translated post exists for the current page language. If a translation
is found, the link points to the localized post; otherwise it falls
back to the original English URL.
---
 _plugins/localize_post_url.rb     | 35 +++++++++++++++++++++++++++++++
 ja/downloads/releases/index.md    |  2 +-
 ko/downloads/releases/index.md    |  2 +-
 uk/downloads/releases/index.md    |  2 +-
 vi/downloads/releases/index.md    |  2 +-
 zh_cn/downloads/releases/index.md |  2 +-
 6 files changed, 40 insertions(+), 5 deletions(-)
 create mode 100644 _plugins/localize_post_url.rb

diff --git a/_plugins/localize_post_url.rb b/_plugins/localize_post_url.rb
new file mode 100644
index 0000000000..3d17651264
--- /dev/null
+++ b/_plugins/localize_post_url.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+module Jekyll
+
+  # Provides a Liquid filter to resolve a localized version of a
+  # post URL when a translation exists for the given language.
+  #
+  # Falls back to the original (English) URL if no translation is found.
+  #
+  # Example:
+  #     {{ release.post | localize_post_url: page.lang }}
+  #
+  module LocalizePostUrlFilter
+
+    def localize_post_url(url, lang)
+      return url if lang.nil? || lang == "en"
+
+      localized_url = url.sub(%r{\A/en/}, "/#{lang}/")
+      return url if localized_url == url
+
+      site = @context.registers[:site]
+
+      # Build a lookup set of all post URLs on first use (cached per site)
+      @post_urls ||= Set.new(site.posts.docs.map(&:url))
+
+      if @post_urls.include?(localized_url)
+        localized_url
+      else
+        url
+      end
+    end
+  end
+end
+
+Liquid::Template.register_filter(Jekyll::LocalizePostUrlFilter)
diff --git a/ja/downloads/releases/index.md b/ja/downloads/releases/index.md
index 21eb6aad9d..41aef4c71b 100644
--- a/ja/downloads/releases/index.md
+++ b/ja/downloads/releases/index.md
@@ -28,6 +28,6 @@ lang: ja
 <td>Ruby {{ release.version }}</td>
 <td>{{ release.date }}</td>
 <td><a href="{{ release.url.gz }}">download</a></td>
-<td><a href="{{ release.post }}">more...</a></td>
+<td><a href="{{ release.post | localize_post_url: page.lang }}">more...</a></td>
 </tr>{% endfor %}
 </table>
diff --git a/ko/downloads/releases/index.md b/ko/downloads/releases/index.md
index 0df0c0d90d..b5b2b900ab 100644
--- a/ko/downloads/releases/index.md
+++ b/ko/downloads/releases/index.md
@@ -29,6 +29,6 @@ Ruby 릴리스 목록입니다.
 <td>Ruby {{ release.version }}</td>
 <td>{{ release.date }}</td>
 <td><a href="{{ release.url.gz }}">다운로드</a></td>
-<td><a href="{{ release.post }}">더 보기...</a></td>
+<td><a href="{{ release.post | localize_post_url: page.lang }}">더 보기...</a></td>
 </tr>{% endfor %}
 </table>
diff --git a/uk/downloads/releases/index.md b/uk/downloads/releases/index.md
index 5032b42074..f9cfc78286 100644
--- a/uk/downloads/releases/index.md
+++ b/uk/downloads/releases/index.md
@@ -30,6 +30,6 @@ lang: uk
 <td>Ruby {{ release.version }}</td>
 <td>{{ release.date }}</td>
 <td><a href="{{ release.url.gz }}">завантажити</a></td>
-<td><a href="{{ release.post }}">детальніше...</a></td>
+<td><a href="{{ release.post | localize_post_url: page.lang }}">детальніше...</a></td>
 </tr>{% endfor %}
 </table>
diff --git a/vi/downloads/releases/index.md b/vi/downloads/releases/index.md
index 3b7f6a21e7..a0ddc9e991 100644
--- a/vi/downloads/releases/index.md
+++ b/vi/downloads/releases/index.md
@@ -30,6 +30,6 @@ các tarball mã nguồn.
 <td>Ruby {{ release.version }}</td>
 <td>{{ release.date }}</td>
 <td><a href="{{ release.url.gz }}">tải về</a></td>
-<td><a href="{{ release.post }}">xem thêm...</a></td>
+<td><a href="{{ release.post | localize_post_url: page.lang }}">xem thêm...</a></td>
 </tr>{% endfor %}
 </table>
diff --git a/zh_cn/downloads/releases/index.md b/zh_cn/downloads/releases/index.md
index 7cfc5e2fa9..d955a7afef 100644
--- a/zh_cn/downloads/releases/index.md
+++ b/zh_cn/downloads/releases/index.md
@@ -28,6 +28,6 @@ lang: zh_cn
 <td>Ruby {{ release.version }}</td>
 <td>{{ release.date }}</td>
 <td><a href="{{ release.url.gz }}">下载</a></td>
-<td><a href="{{ release.post }}">查看…</a></td>
+<td><a href="{{ release.post | localize_post_url: page.lang }}">查看…</a></td>
 </tr>{% endfor %}
 </table>