Emit RedirectsPanel warning on usage rather than set up. (#2326)

* Emit RedirectsPanel warning on usage rather than set up.

* Remove stale test.

The test's doc string was out of alignment with what the test
actually did.

Author: tim-schilling

debug_toolbar/panels/redirects.py

@@ -18,17 +18,6 @@ class RedirectsPanel(Panel):
 
     nav_title = _("Intercept redirects")
 
-    def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)
-        warnings.warn(
-            "The RedirectsPanel is deprecated and will be removed in a future version. "
-            "The HistoryPanel now provides the ability to view toolbar data for redirected requests. "
-            "If you still have a use case for this panel, please comment on "
-            "https://github.com/django-commons/django-debug-toolbar/issues/2216",
-            DeprecationWarning,
-            stacklevel=2,
-        )
-
     def _process_response(self, response):
         """
         Common response processing logic.
@@ -71,4 +60,13 @@ def get_interception_response(self, response, redirect_to):
         response = SimpleTemplateResponse("debug_toolbar/redirect.html", context)
         response.cookies = cookies
         response.original_response = original_response
+
+        warnings.warn(
+            "The RedirectsPanel is deprecated and will be removed in a future version. "
+            "The HistoryPanel now provides the ability to view toolbar data for redirected requests. "
+            "If you still have a use case for this panel, please comment on "
+            "https://github.com/django-commons/django-debug-toolbar/issues/2216",
+            DeprecationWarning,
+            stacklevel=2,
+        )
         return response

docs/changes.rst

@@ -12,6 +12,8 @@ Pending
 * Added translations for Lithuanian, Turkish and Uzbek.
 * Update the translations.
 * Expose a ``py.typed`` marker file.
+* Updated ``RedirectsPanel`` to emit the deprecation warning when it's used
+  rather than on instantiation.
 
 6.2.0 (2026-01-20)
 ------------------

tests/panels/test_redirects.py

@@ -1,25 +1,17 @@
 import copy
-import warnings
 
 from django.conf import settings
 from django.http import HttpResponse
 from django.test import AsyncRequestFactory
 
 from debug_toolbar.panels.redirects import RedirectsPanel
-from debug_toolbar.toolbar import DebugToolbar
 
 from ..base import BaseTestCase
 
 
 class RedirectsPanelTestCase(BaseTestCase):
     panel_id = RedirectsPanel.panel_id
 
-    def setUp(self):
-        # Suppress the deprecation warning during setup
-        with warnings.catch_warnings():
-            warnings.simplefilter("ignore", DeprecationWarning)
-            super().setUp()
-
     def test_regular_response(self):
         not_redirect = HttpResponse()
         self._get_response = lambda request: not_redirect
@@ -70,18 +62,6 @@ def test_unknown_status_code_with_reason(self):
         response = self.panel.process_request(self.request)
         self.assertContains(response, "369 Look Ma!")
 
-    def test_insert_content(self):
-        """
-        Test that the panel only inserts content after generate_stats and
-        not the process_request.
-        """
-        redirect = HttpResponse(status=304)
-        self._get_response = lambda request: redirect
-        response = self.panel.process_request(self.request)
-        self.assertIsNotNone(response)
-        response = self.panel.generate_stats(self.request, redirect)
-        self.assertIsNone(response)
-
     async def test_async_compatibility(self):
         redirect = HttpResponse(status=302)
 
@@ -110,11 +90,13 @@ def test_original_response_preserved(self):
         )
 
     def test_deprecation_warning(self):
-        """Test that a deprecation warning is shown when RedirectsPanel is instantiated."""
+        """Test that a deprecation warning is shown when RedirectsPanel used."""
+        redirect = HttpResponse(status=304)
+        redirect["Location"] = "http://somewhere/else/"
+        self._get_response = lambda request: redirect
 
         with self.assertWarns(DeprecationWarning) as cm:
-            toolbar = DebugToolbar(self.request, self._get_response)
-            toolbar.get_panel_by_id(RedirectsPanel.panel_id)
+            self.panel.process_request(self.request)
 
         self.assertIn("RedirectsPanel is deprecated", str(cm.warning))
         self.assertIn("HistoryPanel", str(cm.warning))