Modified [7112] to make things behave more in line with Python subclassing when subclassing ModelForms.

Meta can now be subclassed and changes on the child model affect the fields
list. Also removed a block of error checking, since it's harder to mess up in
unexpected ways now (e.g. you can't change the model and get the entirely wrong
fields list), so it was a level of overkill.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@7115 bcc190cf-cafb-0310-a4f2-bffc1f526a37

1 files changed, 23 insertions, 14 deletions

diff --git a/tests/modeltests/model_forms/models.py b/tests/modeltests/model_forms/models.py
index 0d429b2a71..c480899f84 100644
--- a/tests/modeltests/model_forms/models.py
+++ b/tests/modeltests/model_forms/models.py
@@ -155,43 +155,52 @@ familiar with the mechanics.
 ...     class Meta:
 ...         model = Category
 
->>> class BadForm(CategoryForm):
+>>> class OddForm(CategoryForm):
 ...     class Meta:
 ...         model = Article
-Traceback (most recent call last):
-...
-ImproperlyConfigured: BadForm's base classes define more than one model.
+
+OddForm is now an Article-related thing, because BadForm.Meta overrides
+CategoryForm.Meta.
+>>> OddForm.base_fields.keys()
+['headline', 'slug', 'pub_date', 'writer', 'article', 'status', 'categories']
 
 >>> class ArticleForm(ModelForm):
 ...     class Meta:
 ...         model = Article
 
+First class with a Meta class wins.
+
 >>> class BadForm(ArticleForm, CategoryForm):
 ...     pass
-Traceback (most recent call last):
-...
-ImproperlyConfigured: BadForm's base classes define more than one model.
+>>> OddForm.base_fields.keys()
+['headline', 'slug', 'pub_date', 'writer', 'article', 'status', 'categories']
 
-This one is OK since the subclass specifies the same model as the parent.
+Subclassing without specifying a Meta on the class will use the parent's Meta
+(or the first parent in the MRO if there are multiple parent classes).
 
->>> class SubCategoryForm(CategoryForm):
+>>> class CategoryForm(ModelForm):
 ...     class Meta:
 ...         model = Category
+>>> class SubCategoryForm(CategoryForm):
+...     pass
+>>> SubCategoryForm.base_fields.keys()
+['name', 'slug', 'url']
 
-
-Subclassing without specifying a Meta on the class will use the parent's Meta
-(or the first parent in the MRO if there are multiple parent classes).
+We can also subclass the Meta inner class to change the fields list.
 
 >>> class CategoryForm(ModelForm):
+...     checkbox = forms.BooleanField()
+...
 ...     class Meta:
 ...         model = Category
-...         exclude = ['url']
 >>> class SubCategoryForm(CategoryForm):
-...     pass
+...     class Meta(CategoryForm.Meta):
+...         exclude = ['url']
 
 >>> print SubCategoryForm()
 <tr><th><label for="id_name">Name:</label></th><td><input id="id_name" type="text" name="name" maxlength="20" /></td></tr>
 <tr><th><label for="id_slug">Slug:</label></th><td><input id="id_slug" type="text" name="slug" maxlength="20" /></td></tr>
+<tr><th><label for="id_checkbox">Checkbox:</label></th><td><input type="checkbox" name="checkbox" id="id_checkbox" /></td></tr>
 
 # Old form_for_x tests #######################################################