Fixed #5975 -- Gave `ModelChoiceField` and `ModelMultipleChoiceField` ability to specify custom error messages.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6694 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/newforms/models.py

@@ -3,7 +3,7 @@ Helper functions for creating Form classes from Django models
 and database field objects.
 """
 
-from django.utils.translation import ugettext
+from django.utils.translation import ugettext_lazy as _
 from django.utils.encoding import smart_unicode
 from django.utils.datastructures import SortedDict
 
@@ -151,15 +151,20 @@ class ModelChoiceField(ChoiceField):
     """A ChoiceField whose choices are a model QuerySet."""
     # This class is a subclass of ChoiceField for purity, but it doesn't
     # actually use any of ChoiceField's implementation.
+    default_error_messages = {
+        'invalid_choice': _(u'Select a valid choice. That choice is not one of'
+                            u' the available choices.'),
+    }
 
     def __init__(self, queryset, empty_label=u"---------", cache_choices=False,
                  required=True, widget=Select, label=None, initial=None,
-                 help_text=None):
+                 help_text=None, *args, **kwargs):
         self.empty_label = empty_label
         self.cache_choices = cache_choices
         # Call Field instead of ChoiceField __init__() because we don't need
         # ChoiceField.__init__().
-        Field.__init__(self, required, widget, label, initial, help_text)
+        Field.__init__(self, required, widget, label, initial, help_text,
+                       *args, **kwargs)
         self.queryset = queryset
 
     def _get_queryset(self):
@@ -200,36 +205,38 @@ class ModelChoiceField(ChoiceField):
         try:
             value = self.queryset.get(pk=value)
         except self.queryset.model.DoesNotExist:
-            raise ValidationError(ugettext(u'Select a valid choice. That'
-                                           u' choice is not one of the'
-                                           u' available choices.'))
+            raise ValidationError(self.error_messages['invalid_choice'])
         return value
 
 class ModelMultipleChoiceField(ModelChoiceField):
     """A MultipleChoiceField whose choices are a model QuerySet."""
     hidden_widget = MultipleHiddenInput
+    default_error_messages = {
+        'list': _(u'Enter a list of values.'),
+        'invalid_choice': _(u'Select a valid choice. %s is not one of the'
+                            u' available choices.'),
+    }
 
     def __init__(self, queryset, cache_choices=False, required=True,
                  widget=SelectMultiple, label=None, initial=None,
-                 help_text=None):
+                 help_text=None, *args, **kwargs):
         super(ModelMultipleChoiceField, self).__init__(queryset, None,
-            cache_choices, required, widget, label, initial, help_text)
+            cache_choices, required, widget, label, initial, help_text,
+            *args, **kwargs)
 
     def clean(self, value):
         if self.required and not value:
-            raise ValidationError(ugettext(u'This field is required.'))
+            raise ValidationError(self.error_messages['required'])
         elif not self.required and not value:
             return []
         if not isinstance(value, (list, tuple)):
-            raise ValidationError(ugettext(u'Enter a list of values.'))
+            raise ValidationError(self.error_messages['list'])
         final_values = []
         for val in value:
             try:
                 obj = self.queryset.get(pk=val)
             except self.queryset.model.DoesNotExist:
-                raise ValidationError(ugettext(u'Select a valid choice. %s is'
-                                               u' not one of the available'
-                                               u' choices.') % val)
+                raise ValidationError(self.error_messages['invalid_choice'] % val)
             else:
                 final_values.append(obj)
         return final_values

tests/regressiontests/forms/error_messages.py

@@ -312,4 +312,49 @@ ValidationError: [u'REQUIRED']
 Traceback (most recent call last):
 ...
 ValidationError: [u'INVALID IP ADDRESS']
+
+###############################################################################
+
+# Create choices for the model choice field tests below.
+
+>>> from regressiontests.forms.models import ChoiceModel
+>>> ChoiceModel.objects.create(pk=1, name='a')
+<ChoiceModel: ChoiceModel object>
+>>> ChoiceModel.objects.create(pk=2, name='b')
+<ChoiceModel: ChoiceModel object>
+>>> ChoiceModel.objects.create(pk=3, name='c')
+<ChoiceModel: ChoiceModel object>
+
+# ModelChoiceField ############################################################
+
+>>> e = {'required': 'REQUIRED'}
+>>> e['invalid_choice'] = 'INVALID CHOICE'
+>>> f = ModelChoiceField(queryset=ChoiceModel.objects.all(), error_messages=e)
+>>> f.clean('')
+Traceback (most recent call last):
+...
+ValidationError: [u'REQUIRED']
+>>> f.clean('4')
+Traceback (most recent call last):
+...
+ValidationError: [u'INVALID CHOICE']
+
+# ModelMultipleChoiceField ####################################################
+
+>>> e = {'required': 'REQUIRED'}
+>>> e['invalid_choice'] = '%s IS INVALID CHOICE'
+>>> e['list'] = 'NOT A LIST OF VALUES'
+>>> f = ModelMultipleChoiceField(queryset=ChoiceModel.objects.all(), error_messages=e)
+>>> f.clean('')
+Traceback (most recent call last):
+...
+ValidationError: [u'REQUIRED']
+>>> f.clean('3')
+Traceback (most recent call last):
+...
+ValidationError: [u'NOT A LIST OF VALUES']
+>>> f.clean(['4'])
+Traceback (most recent call last):
+...
+ValidationError: [u'4 IS INVALID CHOICE']
 """

tests/regressiontests/forms/models.py

@@ -10,6 +10,10 @@ class Defaults(models.Model):
     def_date = models.DateField(default = datetime.date(1980, 1, 1))
     value = models.IntegerField(default=42)
 
+class ChoiceModel(models.Model):
+    """For ModelChoiceField and ModelMultipleChoiceField tests."""
+    name = models.CharField(max_length=10)
+
 __test__ = {'API_TESTS': """
 >>> from django.newforms import form_for_model, form_for_instance