[soc2009/model-validation] Make validators work with error messages containing paramters.

Implemented MaxValueValidator and MinValueValidator and migrated number
based form.Fields to use those instead of hardwired code. The validators
themselves are likely to change.

Covered by existing tests

git-svn-id: http://code.djangoproject.com/svn/django/branches/soc2009/model-validation@11186 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/core/exceptions.py

@@ -35,7 +35,7 @@ class FieldError(Exception):
 NON_FIELD_ERRORS = '__all__'
 class ValidationError(Exception):
     """An error while validating data."""
-    def __init__(self, message, code=None):
+    def __init__(self, message, code=None, params=None):
         import operator
         from django.utils.encoding import force_unicode
         """
@@ -50,6 +50,7 @@ class ValidationError(Exception):
             self.messages = [force_unicode(msg) for msg in message]
         else:
             self.code = code
+            self.params = params
             message = force_unicode(message)
             self.messages = [message]
 

django/core/validators.py

@@ -22,6 +22,29 @@ def validate_email(value):
     if not email_re.search(smart_unicode(value)):
         raise ValidationError(_(u'Enter a valid e-mail address.'), code='invalid')
 
+class MaxValueValidator(object):
+    def __init__(self, max_value):
+        self.max_value = max_value
+
+    def __call__(self, value):
+        if value > self.max_value:
+            raise ValidationError(
+                _(u'Ensure this value is less than or equal to %s.') % self.max_value,
+                code='max_value',
+                params=(self.max_value,)
+            )
+class MinValueValidator(object):
+    def __init__(self, min_value):
+        self.min_value = min_value
+
+    def __call__(self, value):
+        if value < self.min_value:
+            raise ValidationError(
+                _(u'Ensure this value is greater than or equal to %s.') % self.min_value,
+                code='min_value',
+                params=(self.min_value,)
+            )
+
 class ComplexValidator(object):
     def get_value(self, name, all_values, obj):
         assert all_values or obj, "Either all_values or obj must be supplied"

django/forms/fields.py

@@ -128,7 +128,10 @@ class Field(object):
                     v(value)
                 except ValidationError, e:
                     if hasattr(e, 'code'):
-                        errors.append(self.error_messages.get(e.code, e.messages[0]))
+                        message = self.error_messages.get(e.code, e.messages[0])
+                        if e.params:
+                            message = message % e.params
+                        errors.append(message)
                     else:
                         errors.extend(e.messages)
         if errors:
@@ -201,9 +204,13 @@ class IntegerField(Field):
     }
 
     def __init__(self, max_value=None, min_value=None, *args, **kwargs):
-        self.max_value, self.min_value = max_value, min_value
         super(IntegerField, self).__init__(*args, **kwargs)
 
+        if max_value is not None:
+            self.validators.append(validators.MaxValueValidator(max_value))
+        if min_value is not None:
+            self.validators.append(validators.MinValueValidator(min_value))
+
     def to_python(self, value):
         """
         Validates that int() can be called on the input. Returns the result
@@ -219,15 +226,6 @@ class IntegerField(Field):
             raise ValidationError(self.error_messages['invalid'])
         return value
 
-    def validate(self, value):
-        super(IntegerField, self).validate(value)
-        if value in validators.EMPTY_VALUES:
-            return
-        if self.max_value is not None and value > self.max_value:
-            raise ValidationError(self.error_messages['max_value'] % self.max_value)
-        if self.min_value is not None and value < self.min_value:
-            raise ValidationError(self.error_messages['min_value'] % self.min_value)
-
 class FloatField(IntegerField):
     default_error_messages = {
         'invalid': _(u'Enter a number.'),
@@ -261,10 +259,14 @@ class DecimalField(Field):
     }
 
     def __init__(self, max_value=None, min_value=None, max_digits=None, decimal_places=None, *args, **kwargs):
-        self.max_value, self.min_value = max_value, min_value
         self.max_digits, self.decimal_places = max_digits, decimal_places
         Field.__init__(self, *args, **kwargs)
 
+        if max_value is not None:
+            self.validators.append(validators.MaxValueValidator(max_value))
+        if min_value is not None:
+            self.validators.append(validators.MinValueValidator(min_value))
+
     def to_python(self, value):
         """
         Validates that the input is a decimal number. Returns a Decimal
@@ -297,10 +299,6 @@ class DecimalField(Field):
             digits = decimals
         whole_digits = digits - decimals
 
-        if self.max_value is not None and value > self.max_value:
-            raise ValidationError(self.error_messages['max_value'] % self.max_value)
-        if self.min_value is not None and value < self.min_value:
-            raise ValidationError(self.error_messages['min_value'] % self.min_value)
         if self.max_digits is not None and digits > self.max_digits:
             raise ValidationError(self.error_messages['max_digits'] % self.max_digits)
         if self.decimal_places is not None and decimals > self.decimal_places: