From e9381e337fd5c7b2733c95fe6c00094e0bbdecb3 Mon Sep 17 00:00:00 2001
From: Scott Burns <13770321+scott-8@users.noreply.github.com>
Date: Fri, 10 Apr 2026 15:56:41 -0400
Subject: [PATCH] Don't check for URLs if `ROOT_URLCONF` isn't defined

---
 debug_toolbar/apps.py | 15 ++++++++++-----
 docs/changes.rst      |  1 +
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/debug_toolbar/apps.py b/debug_toolbar/apps.py
index 776c6a810..324ea490e 100644
--- a/debug_toolbar/apps.py
+++ b/debug_toolbar/apps.py
@@ -249,12 +249,17 @@ def debug_toolbar_installed_when_running_tests_check(app_configs, **kwargs):
         dt_settings.get_config()["SHOW_TOOLBAR_CALLBACK"]
         != CONFIG_DEFAULTS["SHOW_TOOLBAR_CALLBACK"]
     )
-    try:
-        # Check if the toolbar's urls are installed
-        reverse(f"{APP_NAME}:render_panel")
-        toolbar_urls_installed = True
-    except NoReverseMatch:
+
+    if not hasattr(settings, "ROOT_URLCONF"):
+        # reverse will raise AttributeError if ROOT_URLCONF is not defined
         toolbar_urls_installed = False
+    else:
+        try:
+            # Check if the toolbar's urls are installed
+            reverse(f"{APP_NAME}:render_panel")
+            toolbar_urls_installed = True
+        except NoReverseMatch:
+            toolbar_urls_installed = False
 
     # If the user is using the default SHOW_TOOLBAR_CALLBACK,
     # then the middleware will respect the change to settings.DEBUG.
diff --git a/docs/changes.rst b/docs/changes.rst
index 7af2dd769..e5726591e 100644
--- a/docs/changes.rst
+++ b/docs/changes.rst
@@ -3,6 +3,7 @@ Change log
 
 Pending
 -------
+* Prevent check from failing when ``ROOT_URLCONF`` is not defined.
 
 6.3.0 (2026-04-01)
 ------------------