Refs #20456 -- Moved initialization of HEAD method based on GET to the View.setup() for generic views.

This will ease unit testing of views since setup will essentially do
everything needed to set the view instance up (other than instantiating
it). Credit for idea goes to Vincent Prouillet.

AUTHORS

@@ -286,6 +286,7 @@ answer newbie questions, and generally made Django that much better:
     favo@exoweb.net
     fdr <drfarina@gmail.com>
     Federico Capoano <nemesis@ninux.org>
+    Felipe Lee <felipe.lee.garcia@gmail.com>
     Filip Noetzel <http://filip.noetzel.co.uk/>
     Filip Wasilewski <filip.wasilewski@gmail.com>
     Finn Gruwier Larsen <finn@gruwier.dk>

django/views/generic/base.py

@@ -60,8 +60,6 @@ class View:
 
         def view(request, *args, **kwargs):
             self = cls(**initkwargs)
-            if hasattr(self, 'get') and not hasattr(self, 'head'):
-                self.head = self.get
             self.setup(request, *args, **kwargs)
             if not hasattr(self, 'request'):
                 raise AttributeError(
@@ -82,6 +80,8 @@ class View:
 
     def setup(self, request, *args, **kwargs):
         """Initialize attributes shared by all view methods."""
+        if hasattr(self, 'get') and not hasattr(self, 'head'):
+            self.head = self.get
         self.request = request
         self.args = args
         self.kwargs = kwargs

docs/ref/class-based-views/base.txt

@@ -79,12 +79,9 @@ MRO is an acronym for Method Resolution Order.
 
     .. method:: setup(request, *args, **kwargs)
 
-        Initializes view instance attributes: ``self.request``, ``self.args``,
-        and ``self.kwargs`` prior to :meth:`dispatch`.
+        Performs key view initialization prior to :meth:`dispatch`.
 
-        Overriding this method allows mixins to setup instance attributes for
-        reuse in child classes. When overriding this method, you must call
-        ``super()``.
+        If overriding this method, you must call ``super()``.
 
     .. method:: dispatch(request, *args, **kwargs)
 

tests/generic_views/test_base.py

@@ -113,6 +113,13 @@ class ViewTest(SimpleTestCase):
         response = SimpleView.as_view()(self.rf.head('/'))
         self.assertEqual(response.status_code, 200)
 
+    def test_setup_get_and_head(self):
+        view_instance = SimpleView()
+        self.assertFalse(hasattr(view_instance, 'head'))
+        view_instance.setup(self.rf.get('/'))
+        self.assertTrue(hasattr(view_instance, 'head'))
+        self.assertEqual(view_instance.head, view_instance.get)
+
     def test_head_no_get(self):
         """
         Test a view which supplies no GET method responds to HEAD with HTTP 405.