Fixed #21753 -- Raised exception when both `form_class` and `fields` are specified.

3 files changed, 25 insertions, 0 deletions

diff --git a/docs/ref/class-based-views/mixins-editing.txt b/docs/ref/class-based-views/mixins-editing.txt
index 1a06e2bb97..3dcf28dae3 100644
--- a/docs/ref/class-based-views/mixins-editing.txt
+++ b/docs/ref/class-based-views/mixins-editing.txt
@@ -115,6 +115,17 @@ ModelFormMixin
     :attr:`~django.views.generic.detail.SingleObjectMixin.queryset` attributes,
     describing the type of object that the ``ModelForm`` is manipulating.
 
+    If you specify both the
+    :attr:`~django.views.generic.edit.ModelFormMixin.fields` and
+    :attr:`~django.views.generic.edit.FormMixin.form_class` attributes, an
+    :exc:`~django.core.exceptions.ImproperlyConfigured` exception will be
+    raised.
+
+    .. versionchanged:: 1.8
+
+        Previously if both ``fields`` and ``form_class`` were specified,
+        ``fields`` was silently ignored.
+
     **Mixins**
 
     * :class:`django.views.generic.edit.FormMixin`
diff --git a/docs/releases/1.8.txt b/docs/releases/1.8.txt
index 41a0be4ecc..3175eecf5f 100644
--- a/docs/releases/1.8.txt
+++ b/docs/releases/1.8.txt
@@ -783,6 +783,11 @@ Miscellaneous
   ``<WSGIRequest: GET '/somepath/'>``). This won't change the behavior of
   the :class:`~django.views.debug.SafeExceptionReporterFilter` class.
 
+* Class-based views that use :class:`~django.views.generic.edit.ModelFormMixin`
+  will raise an :exc:`~django.core.exceptions.ImproperlyConfigured` exception
+  when both the ``fields`` and ``form_class`` attributes are specified.
+  Previously, ``fields`` was silently ignored.
+
 .. _deprecated-features-1.8:
 
 Features deprecated in 1.8
diff --git a/docs/topics/class-based-views/generic-editing.txt b/docs/topics/class-based-views/generic-editing.txt
index 8490f0d4fb..be087d7758 100644
--- a/docs/topics/class-based-views/generic-editing.txt
+++ b/docs/topics/class-based-views/generic-editing.txt
@@ -139,11 +139,20 @@ inner ``Meta`` class on :class:`~django.forms.ModelForm`. Unless you define the
 form class in another way, the attribute is required and the view will raise
 an :exc:`~django.core.exceptions.ImproperlyConfigured` exception if it's not.
 
+If you specify both the :attr:`~django.views.generic.edit.ModelFormMixin.fields`
+and :attr:`~django.views.generic.edit.FormMixin.form_class` attributes, an
+:exc:`~django.core.exceptions.ImproperlyConfigured` exception will be raised.
+
 .. versionchanged:: 1.8
 
     Omitting the ``fields`` attribute was previously allowed and resulted in a
     form with all of the model's fields.
 
+.. versionchanged:: 1.8
+
+    Previously if both ``fields`` and ``form_class`` were specified,
+    ``fields`` was silently ignored.
+
 Finally, we hook these new views into the URLconf:
 
 .. snippet::