Fixed #30550 -- Fixed decoding of non-UTF-8 bytes objects in response.json().

django/test/client.py

@@ -650,7 +650,7 @@ class Client(RequestFactory):
                     'Content-Type header is "{0}", not "application/json"'
                     .format(response.get('Content-Type'))
                 )
-            response._json = json.loads(response.content.decode(), **extra)
+            response._json = json.loads(response.content.decode(response.charset), **extra)
         return response._json
 
     def _handle_redirects(self, response, data='', content_type='', **extra):

tests/test_client_regress/tests.py

@@ -1204,6 +1204,11 @@ class RequestMethodStringDataTests(SimpleTestCase):
         response = self.client.get('/json_response/')
         self.assertEqual(response.json(), {'key': 'value'})
 
+    def test_json_charset(self):
+        response = self.client.get('/json_response_latin1/')
+        self.assertEqual(response.charset, 'latin1')
+        self.assertEqual(response.json(), {'a': 'Å'})
+
     def test_json_structured_suffixes(self):
         valid_types = (
             'application/vnd.api+json',

tests/test_client_regress/urls.py

@@ -31,6 +31,7 @@ urlpatterns = [
     path('check_unicode/', views.return_unicode),
     path('check_binary/', views.return_undecodable_binary),
     path('json_response/', views.return_json_response),
+    path('json_response_latin1/', views.return_json_response_latin1),
     path('parse_encoded_text/', views.return_text_file),
     path('check_headers/', views.check_headers),
     path('check_headers_redirect/', RedirectView.as_view(url='/check_headers/')),

tests/test_client_regress/views.py

@@ -109,6 +109,10 @@ def return_json_response(request):
     return JsonResponse({'key': 'value'}, **kwargs)
 
 
+def return_json_response_latin1(request):
+    return HttpResponse(b'{"a":"\xc5"}', content_type='application/json; charset=latin1')
+
+
 def return_text_file(request):
     "A view that parses and returns text as a file."
     match = CONTENT_TYPE_RE.match(request.META['CONTENT_TYPE'])