newforms-admin: Fixed #6117 -- Implemented change history for the admin. This includes the ability to track changes on a newform. Model formsets now only return the changed/new objects saved. A big thanks to Karen Tracey and Alex Gaynor.

git-svn-id: http://code.djangoproject.com/svn/django/branches/newforms-admin@7507 bcc190cf-cafb-0310-a4f2-bffc1f526a37

2 files changed, 31 insertions, 19 deletions

diff --git a/django/newforms/forms.py b/django/newforms/forms.py
index 42dacec6ce..300afb2a5b 100644
--- a/django/newforms/forms.py
+++ b/django/newforms/forms.py
@@ -81,6 +81,7 @@ class BaseForm(StrAndUnicode):
         self.label_suffix = label_suffix
         self.empty_permitted = empty_permitted
         self._errors = None # Stores the errors after clean() has been called.
+        self._changed_data = None
 
         # The base_fields class attribute is the *class-wide* definition of
         # fields. Because a particular *instance* of the class might want to
@@ -243,19 +244,25 @@ class BaseForm(StrAndUnicode):
         """
         Returns True if data differs from initial.
         """
-        # XXX: For now we're asking the individual widgets whether or not the
-        # data has changed. It would probably be more efficient to hash the
-        # initial data, store it in a hidden field, and compare a hash of the
-        # submitted data, but we'd need a way to easily get the string value
-        # for a given field. Right now, that logic is embedded in the render
-        # method of each widget.
-        for name, field in self.fields.items():
-            prefixed_name = self.add_prefix(name)
-            data_value = field.widget.value_from_datadict(self.data, self.files, prefixed_name)
-            initial_value = self.initial.get(name, field.initial)
-            if field.widget._has_changed(initial_value, data_value):
-                return True
-        return False
+        return bool(self.changed_data)
+    
+    def _get_changed_data(self):
+        if self._changed_data is None:
+            self._changed_data = []
+            # XXX: For now we're asking the individual widgets whether or not the
+            # data has changed. It would probably be more efficient to hash the
+            # initial data, store it in a hidden field, and compare a hash of the
+            # submitted data, but we'd need a way to easily get the string value
+            # for a given field. Right now, that logic is embedded in the render
+            # method of each widget.
+            for name, field in self.fields.items():
+                prefixed_name = self.add_prefix(name)
+                data_value = field.widget.value_from_datadict(self.data, self.files, prefixed_name)
+                initial_value = self.initial.get(name, field.initial)
+                if field.widget._has_changed(initial_value, data_value):
+                    self._changed_data.append(name)
+        return self._changed_data
+    changed_data = property(_get_changed_data)
 
     def _get_media(self):
         """
diff --git a/django/newforms/models.py b/django/newforms/models.py
index f12b53dacb..79a9e1a457 100644
--- a/django/newforms/models.py
+++ b/django/newforms/models.py
@@ -328,8 +328,11 @@ class BaseModelFormSet(BaseFormSet):
         return self.save_existing_objects(commit) + self.save_new_objects(commit)
 
     def save_existing_objects(self, commit=True):
+        self.changed_objects = []
+        self.deleted_objects = []
         if not self.get_queryset():
             return []
+
         # Put the objects from self.get_queryset into a dict so they are easy to lookup by pk
         existing_objects = {}
         for obj in self.get_queryset():
@@ -338,23 +341,25 @@ class BaseModelFormSet(BaseFormSet):
         for form in self.initial_forms:
             obj = existing_objects[form.cleaned_data[self.model._meta.pk.attname]]
             if self.can_delete and form.cleaned_data[DELETION_FIELD_NAME]:
+                self.deleted_objects.append(obj)
                 obj.delete()
             else:
-                saved_instances.append(self.save_existing(form, obj, commit=commit))
+                if form.changed_data:
+                    self.changed_objects.append((obj, form.changed_data))
+                    saved_instances.append(self.save_existing(form, obj, commit=commit))
         return saved_instances
 
     def save_new_objects(self, commit=True):
-        new_objects = []
+        self.new_objects = []
         for form in self.extra_forms:
             if not form.has_changed():
                 continue
             # If someone has marked an add form for deletion, don't save the
-            # object. At some point it would be nice if we didn't display
-            # the deletion widget for add forms.
+            # object.
             if self.can_delete and form.cleaned_data[DELETION_FIELD_NAME]:
                 continue
-            new_objects.append(self.save_new(form, commit=commit))
-        return new_objects
+            self.new_objects.append(self.save_new(form, commit=commit))
+        return self.new_objects
 
     def add_fields(self, form, index):
         """Add a hidden field for the object's primary key."""