Skip form validation rules if a field is empty

demo/tests/test_forms.py

@@ -12,8 +12,9 @@
 from freezegun import freeze_time
 
 from formidable.constants import REQUIRED, EDITABLE, READONLY, HIDDEN
-from formidable.models import Formidable
+from formidable.models import Formidable, PresetArg
 from formidable.forms import FormidableForm, widgets, fields
+from formidable.forms.validations.presets import ConfirmationPresets
 
 
 class TestDynamicForm(TestCase):
@@ -776,3 +777,80 @@ def test_from_json_raised_error(self):
         self.assertEqual(len(context.exception.messages), 3)
         for message in context.exception.messages:
             self.assertEqual(message, 'This field is required.')
+
+
+class TestInnerPresets(TestCase):
+
+    def test_confirmation_not_required_field(self):
+        class TestPresets(FormidableForm):
+            number = fields.IntegerField(accesses={
+                'jedi': EDITABLE,
+            })
+            text = fields.CharField(accesses={
+                'jedi': EDITABLE,
+            })
+
+            class Meta:
+                presets = [
+                    ConfirmationPresets(
+                        [PresetArg(slug='left', field_id='number'),
+                         PresetArg(slug='right', value='42')],
+                    ),
+                    ConfirmationPresets(
+                        [PresetArg(slug='left', field_id='text'),
+                         PresetArg(slug='right', value='toto')],
+                    ),
+                ]
+
+        formidable = TestPresets.to_formidable(label='presets')
+        form_class = formidable.get_django_form_class(role='jedi')
+        form = form_class(data={'number': '', 'text': ''})
+        self.assertEqual(len(form.rules), 2)
+        self.assertTrue(form.is_valid(), form.errors)
+
+    def test_confirmation_not_required_fields(self):
+        class TestPresets(FormidableForm):
+            left = fields.IntegerField(accesses={
+                'jedi': REQUIRED,
+            })
+            right = fields.IntegerField(accesses={
+                'jedi': REQUIRED,
+            })
+
+            class Meta:
+                presets = [
+                    ConfirmationPresets(
+                        [PresetArg(slug='left', field_id='left'),
+                         PresetArg(slug='right', field_id='right')],
+                    ),
+                ]
+
+        formidable = TestPresets.to_formidable(label='presets')
+        form_class = formidable.get_django_form_class(role='padawan')
+        form = form_class(data={'left': '', 'right': ''})
+        self.assertTrue(form.is_valid(), form.errors)
+
+    def test_confirmation_required_fields(self):
+        class TestPresets(FormidableForm):
+            left = fields.IntegerField(accesses={
+                'jedi': REQUIRED,
+            })
+            right = fields.IntegerField(accesses={
+                'jedi': REQUIRED,
+            })
+
+            class Meta:
+                presets = [
+                    ConfirmationPresets(
+                        [PresetArg(slug='left', field_id='left'),
+                         PresetArg(slug='right', field_id='right')],
+                    ),
+                ]
+
+        formidable = TestPresets.to_formidable(label='presets')
+        form_class = formidable.get_django_form_class(role='jedi')
+        form = form_class(data={'left': '', 'right': ''})
+        self.assertFalse(form.is_valid(), form.errors)
+        self.assertEqual(len(form.errors), 2)
+        self.assertIn('left', form.errors)
+        self.assertIn('right', form.errors)

formidable/forms/validations/presets.py

@@ -147,7 +147,25 @@ def __init__(self, arguments, message=None):
         self.arguments = arguments
         self.message = message or self.default_message
 
+    def has_empty_fields(self, cleaned_data):
+        def is_empty_value(data):
+            return (data is None or
+                    (isinstance(data, six.string_types) and not data))
+
+        used_fields = {a.field_id for a in self.arguments if a.field_id}
+        # we do not filter out required fields because they can't be empty
+        return any(
+            is_empty_value(cleaned_data.get(name, None))
+            for name in used_fields
+        )
+
     def __call__(self, cleaned_data):
+        if self.has_empty_fields(cleaned_data):
+            # We skip rules using empty fields
+            # If the fields were required then it is already reported in
+            # form.errors. If the fields were not required, then it is not
+            # useful to report an error
+            return True
         kwargs = self.collect_kwargs(cleaned_data)
         if not self.run(**kwargs):
             raise ValidationError(self.get_message(kwargs))