Fix #26220 -- Allowed ModelFormMixin.get_model() to retrieve the model from form_class's Meta.

AUTHORS

@@ -233,6 +233,7 @@ answer newbie questions, and generally made Django that much better:
     Chris Wilson <chris+github@qwirx.com>
     Ciaran McCormick <ciaran@ciaranmccormick.com>
     Claude Paroz <claude@2xlibre.net>
+    Clifford Gama <cliffygamy@gmail.com>
     Clint Ecker
     colin@owlfish.com
     Colin Wood <cwood06@gmail.com>

django/views/generic/edit.py

@@ -1,5 +1,5 @@
 from django.core.exceptions import ImproperlyConfigured
-from django.forms import Form
+from django.forms import Form, ModelForm
 from django.forms import models as model_forms
 from django.http import HttpResponseRedirect
 from django.views.generic.base import ContextMixin, TemplateResponseMixin, View
@@ -113,6 +113,13 @@ class ModelFormMixin(FormMixin, SingleObjectMixin):
             kwargs.update({"instance": self.object})
         return kwargs
 
+    def get_model(self):
+        model = super().get_model()
+        if model is None and self.form_class is not None:
+            if issubclass(self.form_class, ModelForm):
+                model = self.form_class.Meta.model
+        return model
+
     def get_success_url(self):
         """Return the URL to redirect to after processing a valid form."""
         if self.success_url:

docs/ref/class-based-views/flattened-index.txt

@@ -212,7 +212,7 @@ Editing views
 * :attr:`~django.views.generic.edit.FormMixin.form_class` [:meth:`~django.views.generic.edit.ModelFormMixin.get_form_class`]
 * :attr:`~django.views.generic.base.View.http_method_names`
 * :attr:`~django.views.generic.edit.FormMixin.initial` [:meth:`~django.views.generic.edit.FormMixin.get_initial`]
-* :attr:`~django.views.generic.detail.SingleObjectMixin.model` [:meth:`~django.views.generic.detail.SingleObjectMixin.get_model`]
+* :attr:`~django.views.generic.detail.SingleObjectMixin.model` [:meth:`~django.views.generic.edit.ModelFormMixin.get_model`]
 * :attr:`~django.views.generic.detail.SingleObjectMixin.pk_url_kwarg`
 * :attr:`~django.views.generic.edit.FormMixin.prefix` [:meth:`~django.views.generic.edit.FormMixin.get_prefix`]
 * :attr:`~django.views.generic.detail.SingleObjectMixin.query_pk_and_slug`
@@ -236,7 +236,7 @@ Editing views
 * :meth:`~django.views.generic.edit.FormMixin.get_context_data`
 * :meth:`~django.views.generic.edit.FormMixin.get_form`
 * :meth:`~django.views.generic.edit.ModelFormMixin.get_form_kwargs`
-* :meth:`~django.views.generic.detail.SingleObjectMixin.get_model`
+* :meth:`~django.views.generic.edit.ModelFormMixin.get_model`
 * :meth:`~django.views.generic.detail.SingleObjectMixin.get_object`
 * ``head()``
 * :meth:`~django.views.generic.base.View.http_method_not_allowed`
@@ -259,7 +259,7 @@ Editing views
 * :attr:`~django.views.generic.edit.FormMixin.form_class` [:meth:`~django.views.generic.edit.ModelFormMixin.get_form_class`]
 * :attr:`~django.views.generic.base.View.http_method_names`
 * :attr:`~django.views.generic.edit.FormMixin.initial` [:meth:`~django.views.generic.edit.FormMixin.get_initial`]
-* :attr:`~django.views.generic.detail.SingleObjectMixin.model` [:meth:`~django.views.generic.detail.SingleObjectMixin.get_model`]
+* :attr:`~django.views.generic.detail.SingleObjectMixin.model` [:meth:`~django.views.generic.edit.ModelFormMixin.get_model`]
 * :attr:`~django.views.generic.detail.SingleObjectMixin.pk_url_kwarg`
 * :attr:`~django.views.generic.edit.FormMixin.prefix` [:meth:`~django.views.generic.edit.FormMixin.get_prefix`]
 * :attr:`~django.views.generic.detail.SingleObjectMixin.query_pk_and_slug`
@@ -283,7 +283,7 @@ Editing views
 * :meth:`~django.views.generic.edit.FormMixin.get_context_data`
 * :meth:`~django.views.generic.edit.FormMixin.get_form`
 * :meth:`~django.views.generic.edit.ModelFormMixin.get_form_kwargs`
-* :meth:`~django.views.generic.detail.SingleObjectMixin.get_model`
+* :meth:`~django.views.generic.edit.ModelFormMixin.get_model`
 * :meth:`~django.views.generic.detail.SingleObjectMixin.get_object`
 * ``head()``
 * :meth:`~django.views.generic.base.View.http_method_not_allowed`

docs/ref/class-based-views/mixins-editing.txt

@@ -121,9 +121,10 @@ The following mixins are used to construct Django's editing views:
 
     .. attribute:: model
 
-        A model class. Can be explicitly provided, otherwise will be determined
-        by examining ``self.object`` or
-        :attr:`~django.views.generic.detail.SingleObjectMixin.queryset`.
+        A model class. It can be explicitly provided; otherwise, it will be
+        determined by examining ``self.object``,
+        :attr:`~django.views.generic.detail.SingleObjectMixin.queryset`, or the
+        value returned by :meth:`~django.views.generic.edit.ModelFormMixin.get_model`.
 
     .. attribute:: fields
 
@@ -159,6 +160,14 @@ The following mixins are used to construct Django's editing views:
         Add the current instance (``self.object``) to the standard
         :meth:`~django.views.generic.edit.FormMixin.get_form_kwargs`.
 
+    .. method:: get_model()
+
+        .. versionadded:: 5.2
+
+        Return ``self.model`` if specified, or the model defined in the
+        ``form_class``'s ``Meta`` attribute if ``form_class`` is provided as
+        a ``ModelForm``.
+
     .. method:: get_success_url()
 
         Determine the URL to redirect to when the form is successfully

docs/releases/5.2.txt

@@ -231,6 +231,11 @@ Generic Views
   overridden. If ``queryset`` is provided, it takes precedence as the source
   of objects.
 
+* :meth:`~django.views.generic.edit.ModelFormMixin.get_model` is overridden to
+  return the model from the ``ModelForm``'s ``Meta`` class when the view's
+  ``model`` attribute is not defined, allowing for simplified form-based edit
+  views using only ``form_class``.
+
 Internationalization
 ~~~~~~~~~~~~~~~~~~~~
 

tests/generic_views/test_edit.py

@@ -164,7 +164,7 @@ class CreateViewTests(TestCase):
         self.assertIsInstance(res.context["form"], views.AuthorForm)
         self.assertNotIn("object", res.context)
         self.assertNotIn("author", res.context)
-        self.assertTemplateUsed(res, "generic_views/form.html")
+        self.assertTemplateUsed(res, "generic_views/author_form.html")
 
         res = self.client.post(
             "/edit/authors/create/special/",
@@ -324,7 +324,7 @@ class UpdateViewTests(TestCase):
         self.assertEqual(res.context["object"], self.author)
         self.assertEqual(res.context["thingy"], self.author)
         self.assertNotIn("author", res.context)
-        self.assertTemplateUsed(res, "generic_views/form.html")
+        self.assertTemplateUsed(res, "generic_views/author_form.html")
 
         res = self.client.post(
             "/edit/author/%d/update/special/" % self.author.pk,

tests/generic_views/views.py

@@ -144,9 +144,7 @@ class AuthorCreate(generic.CreateView):
 
 
 class SpecializedAuthorCreate(generic.CreateView):
-    model = Author
     form_class = AuthorForm
-    template_name = "generic_views/form.html"
     context_object_name = "thingy"
 
     def get_success_url(self):
@@ -187,9 +185,7 @@ class OneAuthorUpdate(generic.UpdateView):
 
 
 class SpecializedAuthorUpdate(generic.UpdateView):
-    model = Author
     form_class = AuthorForm
-    template_name = "generic_views/form.html"
     context_object_name = "thingy"
 
     def get_success_url(self):