Fixed #32106 -- Preserved HTTP_HOST in test Client when following redirects.

Co-authored-by: David Sanders <shang.xiao.sanders@gmail.com>

django/test/client.py

@@ -901,6 +901,7 @@ class ClientMixin:
             extra["wsgi.url_scheme"] = url.scheme
         if url.hostname:
             extra["SERVER_NAME"] = url.hostname
+            extra["HTTP_HOST"] = url.hostname
         if url.port:
             extra["SERVER_PORT"] = str(url.port)
 

tests/test_client/tests.py

@@ -856,6 +856,13 @@ class ClientTest(TestCase):
             response, "https://www.djangoproject.com/", fetch_redirect_response=False
         )
 
+    @override_settings(ALLOWED_HOSTS=["hostname1", "hostname2"])
+    def test_redirect_with_http_host(self):
+        response = self.client.get(
+            "/redirect_to_different_hostname/", follow=True, HTTP_HOST="hostname1"
+        )
+        self.assertEqual(response.content, b"hostname2")
+
     def test_external_redirect_without_trailing_slash(self):
         """
         Client._handle_redirects() with an empty path.

tests/test_client/urls.py

@@ -25,6 +25,12 @@ urlpatterns = [
         "redirect_view_308_query_string/",
         views.method_saving_308_redirect_query_string_view,
     ),
+    path(
+        "redirect_to_different_hostname/",
+        views.redirect_to_different_hostname,
+        name="redirect_to_different_hostname",
+    ),
+    path("get_host_view/", views.get_host_view, name="get_host_view"),
     path("secure_view/", views.view_with_secure),
     path(
         "permanent_redirect_view/",

tests/test_client/views.py

@@ -179,6 +179,14 @@ def method_saving_308_redirect_view(request):
     return _post_view_redirect(request, 308)
 
 
+def redirect_to_different_hostname(request):
+    return HttpResponseRedirect("https://hostname2/get_host_view/")
+
+
+def get_host_view(request):
+    return HttpResponse(request.get_host())
+
+
 def view_with_secure(request):
     "A view that indicates if the request was secure"
     response = HttpResponse()