Fixed #19034 -- Added proper i18n pluralization for max/min length validation messages

This was made possible by commit 3f1a0c0040. Thanks Evil Clay
for the report and Alexey Boriskin his work on the ticket.

django/core/validators.py

@@ -7,7 +7,7 @@ except ImportError:     # Python 2
     from urlparse import urlsplit, urlunsplit
 
 from django.core.exceptions import ValidationError
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import ugettext_lazy as _, ungettext_lazy
 from django.utils.encoding import force_text
 from django.utils.ipv6 import is_valid_ipv6_address
 from django.utils import six
@@ -209,12 +209,18 @@ class MinValueValidator(BaseValidator):
 class MinLengthValidator(BaseValidator):
     compare = lambda self, a, b: a < b
     clean = lambda self, x: len(x)
-    message = _('Ensure this value has at least %(limit_value)d characters (it has %(show_value)d).')
+    message = ungettext_lazy(
+        'Ensure this value has at least %(limit_value)d character (it has %(show_value)d).',
+        'Ensure this value has at least %(limit_value)d characters (it has %(show_value)d).',
+        'limit_value')
     code = 'min_length'
 
 
 class MaxLengthValidator(BaseValidator):
     compare = lambda self, a, b: a > b
     clean = lambda self, x: len(x)
-    message = _('Ensure this value has at most %(limit_value)d characters (it has %(show_value)d).')
+    message = ungettext_lazy(
+        'Ensure this value has at most %(limit_value)d character (it has %(show_value)d).',
+        'Ensure this value has at most %(limit_value)d characters (it has %(show_value)d).',
+        'limit_value')
     code = 'max_length'

django/forms/fields.py

@@ -28,7 +28,7 @@ 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 import six
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import ugettext_lazy as _, ungettext_lazy
 
 # Provide this import for backwards compatibility.
 from django.core.validators import EMPTY_VALUES
@@ -505,7 +505,10 @@ class FileField(Field):
         'invalid': _("No file was submitted. Check the encoding type on the form."),
         'missing': _("No file was submitted."),
         'empty': _("The submitted file is empty."),
-        'max_length': _('Ensure this filename has at most %(max)d characters (it has %(length)d).'),
+        'max_length': ungettext_lazy(
+            'Ensure this filename has at most %(max)d character (it has %(length)d).',
+            'Ensure this filename has at most %(max)d characters (it has %(length)d).',
+            'max'),
         'contradiction': _('Please either submit a file or check the clear checkbox, not both.')
     }