Fixed #9493 -- Corrected error handling of formsets that violate unique constraints across the component forms. Thanks to Alex Gaynor for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@10682 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/forms/models.py

@@ -6,10 +6,10 @@ and database field objects.
 from django.utils.encoding import smart_unicode, force_unicode
 from django.utils.datastructures import SortedDict
 from django.utils.text import get_text_list, capfirst
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import ugettext_lazy as _, ugettext
 
 from util import ValidationError, ErrorList
-from forms import BaseForm, get_declared_fields
+from forms import BaseForm, get_declared_fields, NON_FIELD_ERRORS
 from fields import Field, ChoiceField, IntegerField, EMPTY_VALUES
 from widgets import Select, SelectMultiple, HiddenInput, MultipleHiddenInput
 from widgets import media_property
@@ -231,6 +231,26 @@ class BaseModelForm(BaseForm):
         return self.cleaned_data
 
     def validate_unique(self):
+        unique_checks, date_checks = self._get_unique_checks()
+        form_errors = []
+        bad_fields = set()
+
+        field_errors, global_errors = self._perform_unique_checks(unique_checks)
+        bad_fields.union(field_errors)
+        form_errors.extend(global_errors)
+
+        field_errors, global_errors = self._perform_date_checks(date_checks)
+        bad_fields.union(field_errors)
+        form_errors.extend(global_errors)
+
+        for field_name in bad_fields:
+            del self.cleaned_data[field_name]
+        if form_errors:
+            # Raise the unique together errors since they are considered
+            # form-wide.
+            raise ValidationError(form_errors)
+
+    def _get_unique_checks(self):
         from django.db.models.fields import FieldDoesNotExist, Field as ModelField
 
         # Gather a list of checks to perform. We only perform unique checks
@@ -271,24 +291,8 @@ class BaseModelForm(BaseForm):
                 date_checks.append(('year', name, f.unique_for_year))
             if f.unique_for_month and self.cleaned_data.get(f.unique_for_month) is not None:
                 date_checks.append(('month', name, f.unique_for_month))
+        return unique_checks, date_checks
 
-        form_errors = []
-        bad_fields = set()
-
-        field_errors, global_errors = self._perform_unique_checks(unique_checks)
-        bad_fields.union(field_errors)
-        form_errors.extend(global_errors)
-
-        field_errors, global_errors = self._perform_date_checks(date_checks)
-        bad_fields.union(field_errors)
-        form_errors.extend(global_errors)
-
-        for field_name in bad_fields:
-            del self.cleaned_data[field_name]
-        if form_errors:
-            # Raise the unique together errors since they are considered
-            # form-wide.
-            raise ValidationError(form_errors)
 
     def _perform_unique_checks(self, unique_checks):
         bad_fields = set()
@@ -504,6 +508,96 @@ class BaseModelFormSet(BaseFormSet):
             self.save_m2m = save_m2m
         return self.save_existing_objects(commit) + self.save_new_objects(commit)
 
+    def clean(self):
+        self.validate_unique()
+
+    def validate_unique(self):
+        # Iterate over the forms so that we can find one with potentially valid
+        # data from which to extract the error checks
+        for form in self.forms:
+            if hasattr(form, 'cleaned_data'):
+                break
+        else:
+            return
+        unique_checks, date_checks = form._get_unique_checks()
+        errors = []
+        # Do each of the unique checks (unique and unique_together)
+        for unique_check in unique_checks:
+            seen_data = set()
+            for form in self.forms:
+                # if the form doesn't have cleaned_data then we ignore it,
+                # it's already invalid
+                if not hasattr(form, "cleaned_data"):
+                    continue
+                # get each of the fields for which we have data on this form
+                if [f for f in unique_check if f in form.cleaned_data and form.cleaned_data[f] is not None]:
+                    # get the data itself
+                    row_data = tuple([form.cleaned_data[field] for field in unique_check])
+                    # if we've aready seen it then we have a uniqueness failure
+                    if row_data in seen_data:
+                        # poke error messages into the right places and mark
+                        # the form as invalid
+                        errors.append(self.get_unique_error_message(unique_check))
+                        form._errors[NON_FIELD_ERRORS] = self.get_form_error()
+                        del form.cleaned_data
+                        break
+                    # mark the data as seen
+                    seen_data.add(row_data)
+        # iterate over each of the date checks now
+        for date_check in date_checks:
+            seen_data = set()
+            lookup, field, unique_for = date_check
+            for form in self.forms:
+                # if the form doesn't have cleaned_data then we ignore it,
+                # it's already invalid
+                if not hasattr(self, 'cleaned_data'):
+                    continue
+                # see if we have data for both fields
+                if (form.cleaned_data and form.cleaned_data[field] is not None
+                    and form.cleaned_data[unique_for] is not None):
+                    # if it's a date lookup we need to get the data for all the fields
+                    if lookup == 'date':
+                        date = form.cleaned_data[unique_for]
+                        date_data = (date.year, date.month, date.day)
+                    # otherwise it's just the attribute on the date/datetime
+                    # object
+                    else:
+                        date_data = (getattr(form.cleaned_data[unique_for], lookup),)
+                    data = (form.cleaned_data[field],) + date_data
+                    # if we've aready seen it then we have a uniqueness failure
+                    if data in seen_data:
+                        # poke error messages into the right places and mark
+                        # the form as invalid
+                        errors.append(self.get_date_error_message(date_check))
+                        form._errors[NON_FIELD_ERRORS] = self.get_form_error()
+                        del form.cleaned_data
+                        break
+                    seen_data.add(data)
+        if errors:
+            raise ValidationError(errors)
+
+    def get_unique_error_message(self, unique_check):
+        if len(unique_check) == 1:
+            return ugettext("Please correct the duplicate data for %(field)s.") % {
+                "field": unique_check[0],
+            }
+        else:
+            return ugettext("Please correct the duplicate data for %(field)s, "
+                "which must be unique.") % {
+                    "field": get_text_list(unique_check, _("and")),
+                }
+
+    def get_date_error_message(self, date_check):
+        return ugettext("Please correct the duplicate data for %(field_name)s "
+            "which must be unique for the %(lookup)s in %(date_field)s.") % {
+            'field_name': date_check[1],
+            'date_field': date_check[2],
+            'lookup': unicode(date_check[0]),
+        }
+
+    def get_form_error(self):
+        return ugettext("Please correct the duplicate values below.")
+
     def save_existing_objects(self, commit=True):
         self.changed_objects = []
         self.deleted_objects = []
@@ -657,6 +751,10 @@ class BaseInlineFormSet(BaseModelFormSet):
                 label=getattr(form.fields.get(self.fk.name), 'label', capfirst(self.fk.verbose_name))
             )
 
+    def get_unique_error_message(self, unique_check):
+        unique_check = [field for field in unique_check if field != self.fk.name]
+        return super(BaseInlineFormSet, self).get_unique_error_message(unique_check)
+
 def _get_foreign_key(parent_model, model, fk_name=None):
     """
     Finds and returns the ForeignKey from model to parent if there is one.

docs/topics/forms/modelforms.txt

@@ -515,6 +515,22 @@ exclude::
 
 .. _saving-objects-in-the-formset:
 
+Overriding clean() method
+-------------------------
+
+You can override the ``clean()`` method to provide custom validation to
+the whole formset at once. By default, the ``clean()`` method will validate
+that none of the data in the formsets violate the unique constraints on your
+model (both field ``unique`` and model ``unique_together``). To maintain this
+default behavior be sure you call the parent's ``clean()`` method::
+
+    class MyModelFormSet(BaseModelFormSet):
+        def clean(self):
+            super(MyModelFormSet, self).clean()
+            # example custom validation across forms in the formset:
+            for form in self.forms:
+                # your custom formset validation
+
 Saving objects in the formset
 -----------------------------
 
@@ -599,6 +615,17 @@ than that of a "normal" formset. The only difference is that we call
 ``formset.save()`` to save the data into the database. (This was described
 above, in :ref:`saving-objects-in-the-formset`.)
 
+
+Overiding ``clean()`` on a ``model_formset``
+--------------------------------------------
+
+Just like with ``ModelForms``, by default the ``clean()`` method of a
+``model_formset`` will validate that none of the items in the formset validate
+the unique constraints on your model(either unique or unique_together).  If you
+want to overide the ``clean()`` method on a ``model_formset`` and maintain this
+validation, you must call the parent classes ``clean`` method.
+
+
 Using a custom queryset
 ~~~~~~~~~~~~~~~~~~~~~~~
 

tests/modeltests/model_formsets/models.py

@@ -23,6 +23,12 @@ class Book(models.Model):
     author = models.ForeignKey(Author)
     title = models.CharField(max_length=100)
 
+    class Meta:
+        unique_together = (
+            ('author', 'title'),
+        )
+        ordering = ['id']
+
     def __unicode__(self):
         return self.title
 
@@ -166,6 +172,15 @@ class Poem(models.Model):
     def __unicode__(self):
         return self.name
 
+class Post(models.Model):
+    title = models.CharField(max_length=50, unique_for_date='posted', blank=True)
+    slug = models.CharField(max_length=50, unique_for_year='posted', blank=True)
+    subtitle = models.CharField(max_length=50, unique_for_month='posted', blank=True)
+    posted = models.DateField()
+
+    def __unicode__(self):
+        return self.name
+
 __test__ = {'API_TESTS': """
 
 >>> from datetime import date
@@ -943,4 +958,129 @@ True
 >>> FormSet = modelformset_factory(ClassyMexicanRestaurant, fields=["tacos_are_yummy"])
 >>> sorted(FormSet().forms[0].fields.keys())
 ['restaurant', 'tacos_are_yummy']
+
+# Prevent duplicates from within the same formset
+>>> FormSet = modelformset_factory(Product, extra=2)
+>>> data = {
+...     'form-TOTAL_FORMS': 2,
+...     'form-INITIAL_FORMS': 0,
+...     'form-0-slug': 'red_car',
+...     'form-1-slug': 'red_car',
+... }
+>>> formset = FormSet(data)
+>>> formset.is_valid()
+False
+>>> formset._non_form_errors
+[u'Please correct the duplicate data for slug.']
+
+>>> FormSet = modelformset_factory(Price, extra=2)
+>>> data = {
+...     'form-TOTAL_FORMS': 2,
+...     'form-INITIAL_FORMS': 0,
+...     'form-0-price': '25',
+...     'form-0-quantity': '7',
+...     'form-1-price': '25',
+...     'form-1-quantity': '7',
+... }
+>>> formset = FormSet(data)
+>>> formset.is_valid()
+False
+>>> formset._non_form_errors
+[u'Please correct the duplicate data for price and quantity, which must be unique.']
+
+# only the price field is specified, this should skip any unique checks since the unique_together is not fulfilled.
+# this will fail with a KeyError if broken.
+>>> FormSet = modelformset_factory(Price, fields=("price",), extra=2)
+>>> data = {
+...     'form-TOTAL_FORMS': '2',
+...     'form-INITIAL_FORMS': '0',
+...     'form-0-price': '24',
+...     'form-1-price': '24',
+... }
+>>> formset = FormSet(data)
+>>> formset.is_valid()
+True
+
+>>> FormSet = inlineformset_factory(Author, Book, extra=0)
+>>> author = Author.objects.order_by('id')[0]
+>>> book_ids = author.book_set.values_list('id', flat=True)
+>>> data = {
+...     'book_set-TOTAL_FORMS': '2',
+...     'book_set-INITIAL_FORMS': '2',
+...
+...     'book_set-0-title': 'The 2008 Election',
+...     'book_set-0-author': str(author.id),
+...     'book_set-0-id': str(book_ids[0]),
+...
+...     'book_set-1-title': 'The 2008 Election',
+...     'book_set-1-author': str(author.id),
+...     'book_set-1-id': str(book_ids[1]),
+... }
+>>> formset = FormSet(data=data, instance=author)
+>>> formset.is_valid()
+False
+>>> formset._non_form_errors
+[u'Please correct the duplicate data for title.']
+>>> formset.errors
+[{}, {'__all__': u'Please correct the duplicate values below.'}]
+
+>>> FormSet = modelformset_factory(Post, extra=2)
+>>> data = {
+...     'form-TOTAL_FORMS': '2',
+...     'form-INITIAL_FORMS': '0',
+...
+...     'form-0-title': 'blah',
+...     'form-0-slug': 'Morning',
+...     'form-0-subtitle': 'foo',
+...     'form-0-posted': '2009-01-01',
+...     'form-1-title': 'blah',
+...     'form-1-slug': 'Morning in Prague',
+...     'form-1-subtitle': 'rawr',
+...     'form-1-posted': '2009-01-01'
+... }
+>>> formset = FormSet(data)
+>>> formset.is_valid()
+False
+>>> formset._non_form_errors
+[u'Please correct the duplicate data for title which must be unique for the date in posted.']
+>>> formset.errors
+[{}, {'__all__': u'Please correct the duplicate values below.'}]
+
+>>> data = {
+...     'form-TOTAL_FORMS': '2',
+...     'form-INITIAL_FORMS': '0',
+...
+...     'form-0-title': 'foo',
+...     'form-0-slug': 'Morning in Prague',
+...     'form-0-subtitle': 'foo',
+...     'form-0-posted': '2009-01-01',
+...     'form-1-title': 'blah',
+...     'form-1-slug': 'Morning in Prague',
+...     'form-1-subtitle': 'rawr',
+...     'form-1-posted': '2009-08-02'
+... }
+>>> formset = FormSet(data)
+>>> formset.is_valid()
+False
+>>> formset._non_form_errors
+[u'Please correct the duplicate data for slug which must be unique for the year in posted.']
+
+>>> data = {
+...     'form-TOTAL_FORMS': '2',
+...     'form-INITIAL_FORMS': '0',
+...
+...     'form-0-title': 'foo',
+...     'form-0-slug': 'Morning in Prague',
+...     'form-0-subtitle': 'rawr',
+...     'form-0-posted': '2008-08-01',
+...     'form-1-title': 'blah',
+...     'form-1-slug': 'Prague',
+...     'form-1-subtitle': 'rawr',
+...     'form-1-posted': '2009-08-02'
+... }
+>>> formset = FormSet(data)
+>>> formset.is_valid()
+False
+>>> formset._non_form_errors
+[u'Please correct the duplicate data for subtitle which must be unique for the month in posted.']
 """}