Fixed #23162 -- Renamed forms.Field._has_changed() to has_changed().

django/contrib/auth/forms.py

@@ -64,7 +64,7 @@ def bound_data(self, data, initial):
         # render an input field.
         return initial
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         return False
 
 

django/contrib/auth/tests/test_forms.py

@@ -533,4 +533,4 @@ def test_bug_19349_render_with_none_value(self):
 
     def test_readonly_field_has_changed(self):
         field = ReadOnlyPasswordHashField()
-        self.assertFalse(field._has_changed('aaa', 'bbb'))
+        self.assertFalse(field.has_changed('aaa', 'bbb'))

django/contrib/gis/forms/fields.py

@@ -81,7 +81,7 @@ def clean(self, value):
 
         return geom
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         """ Compare geographic value of data with its initial value. """
 
         try:

django/contrib/gis/tests/geoadmin/tests.py

@@ -44,7 +44,7 @@ def test_olwidget_has_changed(self):
         """
         geoadmin = admin.site._registry[City]
         form = geoadmin.get_changelist_form(None)()
-        has_changed = form.fields['point']._has_changed
+        has_changed = form.fields['point'].has_changed
 
         initial = Point(13.4197458572965953, 52.5194108501149799, srid=4326)
         data_same = "SRID=3857;POINT(1493879.2754093995 6894592.019687599)"

django/forms/fields.py

@@ -25,7 +25,7 @@
 from django.utils import formats
 from django.utils.encoding import smart_text, force_str, force_text
 from django.utils.ipv6 import clean_ipv6_address
-from django.utils.deprecation import RemovedInDjango19Warning, RemovedInDjango20Warning
+from django.utils.deprecation import RemovedInDjango19Warning, RemovedInDjango20Warning, RenameMethodsBase
 from django.utils import six
 from django.utils.six.moves.urllib.parse import urlsplit, urlunsplit
 from django.utils.translation import ugettext_lazy as _, ungettext_lazy
@@ -45,7 +45,13 @@
 )
 
 
-class Field(object):
+class RenameFieldMethods(RenameMethodsBase):
+    renamed_methods = (
+        ('_has_changed', 'has_changed', RemovedInDjango20Warning),
+    )
+
+
+class Field(six.with_metaclass(RenameFieldMethods, object)):
     widget = TextInput  # Default widget to use when rendering this type of Field.
     hidden_widget = HiddenInput  # Default widget to use when rendering this as "hidden".
     default_validators = []  # Default set of validators
@@ -185,7 +191,7 @@ def get_limit_choices_to(self):
             return self.limit_choices_to()
         return self.limit_choices_to
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         """
         Return True if data differs from initial.
         """
@@ -629,7 +635,7 @@ def bound_data(self, data, initial):
             return initial
         return data
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         if data is None:
             return False
         return True
@@ -744,7 +750,7 @@ def validate(self, value):
         if not value and self.required:
             raise ValidationError(self.error_messages['required'], code='required')
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         # Sometimes data or initial could be None or '' which should be the
         # same thing as False.
         if initial == 'False':
@@ -779,7 +785,7 @@ def to_python(self, value):
     def validate(self, value):
         pass
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         # None (unknown) and False (No) are not the same
         if initial is not None:
             initial = bool(initial)
@@ -906,7 +912,7 @@ def validate(self, value):
                     params={'value': val},
                 )
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         if initial is None:
             initial = []
         if data is None:
@@ -1084,14 +1090,14 @@ def compress(self, data_list):
         """
         raise NotImplementedError('Subclasses must implement this method.')
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         if initial is None:
             initial = ['' for x in range(0, len(data))]
         else:
             if not isinstance(initial, list):
                 initial = self.widget.decompress(initial)
         for field, initial, data in zip(self.fields, initial, data):
-            if field._has_changed(field.to_python(initial), data):
+            if field.has_changed(field.to_python(initial), data):
                 return True
         return False
 

django/forms/forms.py

@@ -443,7 +443,7 @@ def changed_data(self):
                         # Always assume data has changed if validation fails.
                         self._changed_data.append(name)
                         continue
-                if field._has_changed(initial_value, data_value):
+                if field.has_changed(initial_value, data_value):
                     self._changed_data.append(name)
         return self._changed_data
 

django/forms/models.py

@@ -1058,7 +1058,7 @@ def clean(self, value):
             raise ValidationError(self.error_messages['invalid_choice'], code='invalid_choice')
         return self.parent_instance
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         return False
 
 
@@ -1186,7 +1186,7 @@ def to_python(self, value):
     def validate(self, value):
         return Field.validate(self, value)
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         initial_value = initial if initial is not None else ''
         data_value = data if data is not None else ''
         return force_text(self.prepare_value(initial_value)) != force_text(data_value)
@@ -1254,7 +1254,7 @@ def prepare_value(self, value):
             return [super(ModelMultipleChoiceField, self).prepare_value(v) for v in value]
         return super(ModelMultipleChoiceField, self).prepare_value(value)
 
-    def _has_changed(self, initial, data):
+    def has_changed(self, initial, data):
         if initial is None:
             initial = []
         if data is None:

docs/internals/deprecation.txt

@@ -46,6 +46,9 @@ about each item can often be found in the release notes of two versions prior.
 
 * Support for string ``view`` arguments to ``url()`` will be removed.
 
+* The backward compatible shim  to rename ``django.forms.Form._has_changed()``
+  to ``has_changed()`` will be removed.
+
 .. _deprecation-removed-in-1.9:
 
 1.9

docs/ref/forms/api.txt

@@ -279,7 +279,9 @@ so that the comparison can be done:
     >>> f.has_changed()
 
 ``has_changed()`` will be ``True`` if the data from ``request.POST`` differs
-from what was provided in :attr:`~Form.initial` or ``False`` otherwise.
+from what was provided in :attr:`~Form.initial` or ``False`` otherwise. The
+result is computed by calling :meth:`Field.has_changed` for each field in the
+form.
 
 Accessing the fields from the form
 ----------------------------------

docs/ref/forms/fields.txt

@@ -299,6 +299,24 @@ as the rendered output.
 See the :ref:`format localization <format-localization>` documentation for
 more information.
 
+
+Checking if the field data has changed
+--------------------------------------
+
+``has_changed()``
+~~~~~~~~~~~~~~~~~~
+
+.. method:: Field.has_changed()
+
+.. versionchanged:: 1.8
+
+    This method was renamed from ``_has_changed()``.
+
+The ``has_changed()`` method is used to determine if the field value has changed
+from the initial value. Returns ``True`` or ``False``.
+
+See the :class:`Form.has_changed()` documentation for more information.
+
 .. _built-in-fields:
 
 Built-in ``Field`` classes

docs/releases/1.8.txt

@@ -676,3 +676,9 @@ An older (pre-1.0), more restrictive and verbose input format for the
 Using the new syntax, this becomes::
 
     ``['States', ['Kansas', ['Lawrence', 'Topeka'], 'Illinois']]``
+
+``django.forms.Field._has_changed()``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Rename this method to :meth:`~django.forms.Field.has_changed` by removing the
+leading underscore. The old name will still work until Django 2.0.

tests/forms_tests/tests/test_extra.py

@@ -443,19 +443,19 @@ def compress(self, data_list):
         self.assertFormErrors(['This field is required.'], f.clean, ['some text', ['JP']])
 
         # test with no initial data
-        self.assertTrue(f._has_changed(None, ['some text', ['J', 'P'], ['2007-04-25', '6:24:00']]))
+        self.assertTrue(f.has_changed(None, ['some text', ['J', 'P'], ['2007-04-25', '6:24:00']]))
 
         # test when the data is the same as initial
-        self.assertFalse(f._has_changed('some text,JP,2007-04-25 06:24:00',
+        self.assertFalse(f.has_changed('some text,JP,2007-04-25 06:24:00',
             ['some text', ['J', 'P'], ['2007-04-25', '6:24:00']]))
 
         # test when the first widget's data has changed
-        self.assertTrue(f._has_changed('some text,JP,2007-04-25 06:24:00',
+        self.assertTrue(f.has_changed('some text,JP,2007-04-25 06:24:00',
             ['other text', ['J', 'P'], ['2007-04-25', '6:24:00']]))
 
         # test when the last widget's data has changed. this ensures that it is not
         # short circuiting while testing the widgets.
-        self.assertTrue(f._has_changed('some text,JP,2007-04-25 06:24:00',
+        self.assertTrue(f.has_changed('some text,JP,2007-04-25 06:24:00',
             ['some text', ['J', 'P'], ['2009-04-25', '11:44:00']]))
 
         class ComplexFieldForm(Form):
@@ -803,7 +803,7 @@ def test_l10n(self):
 
     def test_l10n_date_changed(self):
         """
-        Ensure that DateField._has_changed() with SelectDateWidget works
+        Ensure that DateField.has_changed() with SelectDateWidget works
         correctly with a localized date format.
         Refs #17165.
         """