\#527 Fixes issue where the history button doesn't work when viewing a historical entry

Author: trumpet2012

AUTHORS.rst

@@ -146,6 +146,7 @@ Authors
 - `DanialErfanian <https://github.com/DanialErfanian>`_
 - `Sridhar Marella <https://github.com/sridhar562345>`_
 - `Mattia Fantoni <https://github.com/MattFanto>`_
+- `Trent Holliday <https://github.com/trumpet2012>`_
 
 Background
 ==========

CHANGES.rst

@@ -13,6 +13,8 @@ Unreleased
 - Dropped support for Python 3.8, which reached end-of-life on 2024-10-07 (gh-1421)
 - Added support for Django 5.1 (gh-1388)
 - Added pagination to ``SimpleHistoryAdmin`` (gh-1277)
+- Fixed issue with history button not working when viewing historical entries in the
+  admin (gh-527)
 
 3.7.0 (2024-05-29)
 ------------------

simple_history/templates/simple_history/object_history_form.html

@@ -1,5 +1,5 @@
 {% extends "admin/change_form.html" %}
-{% load i18n %}
+{% load i18n admin_urls %}
 {% load url from simple_history_compat %}
 
 {% block breadcrumbs %}
@@ -21,6 +21,14 @@
   {% include "simple_history/submit_line.html" %}
 {% endblock %}
 
+{% block object-tools-items %}
+{# We override this block from the django template to fix up the history link #}
+<li>
+    <a href="{% add_preserved_filters history_url %}" class="historylink">{% translate "History" %}</a>
+</li>
+{% if has_absolute_url %}<li><a href="{{ absolute_url }}" class="viewsitelink">{% translate "View on site" %}</a></li>{% endif %}
+{% endblock %}
+
 {% block form_top %}
 <p>{% if not revert_disabled %}{% blocktrans %}Press the 'Revert' button below to revert to this version of the object.{% endblocktrans %}{% endif %}{% if change_history %}{% blocktrans %}Press the 'Change History' button below to edit the history.{% endblocktrans %}{% endif %}</p>
 {% endblock %}