Fixed #22799 -- Made GET and POST on HttpRequest QueryDicts, and FILES a MultiValueDict.

Previously, GET, POST, and FILES on an HttpRequest were created in
the __init__ method as dictionaries. This was not something you would
usually notice causing trouble in production as you'd only see a
WSGIRequest, but in testing using the test client, calling .getlist
on GET, POST, or FILES for a request with no get/post data resulted in
an AttributeError.

Changed GET and POST on an HttpRequest object to be mutable
QueryDicts (mutable because the Django tests, and probably many
third party tests, were expecting it).

3 files changed, 19 insertions, 1 deletions

diff --git a/django/http/request.py b/django/http/request.py
index e5e4c51114..175cdd58b5 100644
--- a/django/http/request.py
+++ b/django/http/request.py
@@ -49,7 +49,12 @@ class HttpRequest(object):
         # Any variable assignment made here should also happen in
         # `WSGIRequest.__init__()`.
 
-        self.GET, self.POST, self.COOKIES, self.META, self.FILES = {}, {}, {}, {}, {}
+        self.GET = QueryDict(mutable=True)
+        self.POST = QueryDict(mutable=True)
+        self.COOKIES = {}
+        self.META = {}
+        self.FILES = MultiValueDict()
+
         self.path = ''
         self.path_info = ''
         self.method = None
diff --git a/docs/releases/1.8.txt b/docs/releases/1.8.txt
index 11b051fc70..96bcc55051 100644
--- a/docs/releases/1.8.txt
+++ b/docs/releases/1.8.txt
@@ -220,6 +220,12 @@ Requests and Responses
   instantiated with ``QueryDict()`` instead of ``QueryDict(None)`` or
   ``QueryDict('')``.
 
+* The ``GET`` and ``POST`` attributes of an :class:`~django.http.HttpRequest`
+  object are now :class:`~django.http.QueryDict`\s rather than dictionaries,
+  and the ``FILES`` attribute is now a ``MultiValueDict``.
+  This brings this class into line with the documentation and with
+  ``WSGIRequest``.
+
 Tests
 ^^^^^
 
diff --git a/tests/requests/tests.py b/tests/requests/tests.py
index 3f30f75eea..b778fe3718 100644
--- a/tests/requests/tests.py
+++ b/tests/requests/tests.py
@@ -27,6 +27,13 @@ class RequestsTests(SimpleTestCase):
         self.assertEqual(list(request.COOKIES.keys()), [])
         self.assertEqual(list(request.META.keys()), [])
 
+        # .GET and .POST should be QueryDicts
+        self.assertEqual(request.GET.urlencode(), '')
+        self.assertEqual(request.POST.urlencode(), '')
+
+        # and FILES should be MultiValueDict
+        self.assertEqual(request.FILES.getlist('foo'), [])
+
     def test_httprequest_repr(self):
         request = HttpRequest()
         request.path = '/somepath/'