Improved error message display during validation errors.

When reporting a validation error (during model validation or fixture
loading, for example), the error messages now report the bad value as
well as the expected type. This can make identifying the offending field
and problem a bit easier.

Fixed #11595. Patch from raulcd and wildfire with supervision from
Russell.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16638 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/fields/__init__.py

@@ -462,7 +462,7 @@ class AutoField(Field):
 
     empty_strings_allowed = False
     default_error_messages = {
-        'invalid': _(u'This value must be an integer.'),
+        'invalid': _(u"'%s' value must be an integer."),
     }
     def __init__(self, *args, **kwargs):
         assert kwargs.get('primary_key', False) is True, "%ss must have primary_key=True." % self.__class__.__name__
@@ -478,7 +478,8 @@ class AutoField(Field):
         try:
             return int(value)
         except (TypeError, ValueError):
-            raise exceptions.ValidationError(self.error_messages['invalid'])
+            msg = self.error_messages['invalid'] % str(value)
+            raise exceptions.ValidationError(msg)
 
     def validate(self, value, model_instance):
         pass
@@ -500,7 +501,7 @@ class AutoField(Field):
 class BooleanField(Field):
     empty_strings_allowed = False
     default_error_messages = {
-        'invalid': _(u'This value must be either True or False.'),
+        'invalid': _(u"'%s' value must be either True or False."),
     }
     description = _("Boolean (Either True or False)")
     def __init__(self, *args, **kwargs):
@@ -521,7 +522,8 @@ class BooleanField(Field):
             return True
         if value in ('f', 'False', '0'):
             return False
-        raise exceptions.ValidationError(self.error_messages['invalid'])
+        msg = self.error_messages['invalid'] % str(value)
+        raise exceptions.ValidationError(msg)
 
     def get_prep_lookup(self, lookup_type, value):
         # Special-case handling for filters coming from a Web request (e.g. the
@@ -753,7 +755,7 @@ class DateTimeField(DateField):
 class DecimalField(Field):
     empty_strings_allowed = False
     default_error_messages = {
-        'invalid': _(u'This value must be a decimal number.'),
+        'invalid': _(u"'%s' value must be a decimal number."),
     }
     description = _("Decimal number")
 
@@ -770,7 +772,8 @@ class DecimalField(Field):
         try:
             return decimal.Decimal(value)
         except decimal.InvalidOperation:
-            raise exceptions.ValidationError(self.error_messages['invalid'])
+            msg = self.error_messages['invalid'] % str(value)
+            raise exceptions.ValidationError(msg)
 
     def _format(self, value):
         if isinstance(value, basestring) or value is None:
@@ -848,7 +851,7 @@ class FilePathField(Field):
 class FloatField(Field):
     empty_strings_allowed = False
     default_error_messages = {
-        'invalid': _("This value must be a float."),
+        'invalid': _("'%s' value must be a float."),
     }
     description = _("Floating point number")
 
@@ -866,7 +869,8 @@ class FloatField(Field):
         try:
             return float(value)
         except (TypeError, ValueError):
-            raise exceptions.ValidationError(self.error_messages['invalid'])
+            msg = self.error_messages['invalid'] % str(value)
+            raise exceptions.ValidationError(msg)
 
     def formfield(self, **kwargs):
         defaults = {'form_class': forms.FloatField}
@@ -876,7 +880,7 @@ class FloatField(Field):
 class IntegerField(Field):
     empty_strings_allowed = False
     default_error_messages = {
-        'invalid': _("This value must be an integer."),
+        'invalid': _("'%s' value must be an integer."),
     }
     description = _("Integer")
 
@@ -900,7 +904,8 @@ class IntegerField(Field):
         try:
             return int(value)
         except (TypeError, ValueError):
-            raise exceptions.ValidationError(self.error_messages['invalid'])
+            msg = self.error_messages['invalid'] % str(value)
+            raise exceptions.ValidationError(msg)
 
     def formfield(self, **kwargs):
         defaults = {'form_class': forms.IntegerField}
@@ -981,7 +986,7 @@ class GenericIPAddressField(Field):
 class NullBooleanField(Field):
     empty_strings_allowed = False
     default_error_messages = {
-        'invalid': _("This value must be either None, True or False."),
+        'invalid': _("'%s' value must be either None, True or False."),
     }
     description = _("Boolean (Either True, False or None)")
 
@@ -1004,7 +1009,8 @@ class NullBooleanField(Field):
             return True
         if value in ('f', 'False', '0'):
             return False
-        raise exceptions.ValidationError(self.error_messages['invalid'])
+        msg = self.error_messages['invalid'] % str(value)
+        raise exceptions.ValidationError(msg)
 
     def get_prep_lookup(self, lookup_type, value):
         # Special-case handling for filters coming from a Web request (e.g. the

tests/modeltests/validation/test_error_messages.py

+from django.core.exceptions import ValidationError
+from django.utils.unittest import TestCase
+from django.db import models
+
+
+class ValidationMessagesTest(TestCase):
+
+    def test_autofield_field_raises_error_message(self):
+        f = models.AutoField(primary_key=True)
+        self.assertRaises(ValidationError, f.clean, 'foo', None)
+        try:
+            f.clean('foo', None)
+        except ValidationError, e:
+            self.assertEqual(e.messages, [u"'foo' value must be an integer."])
+
+    def test_integer_field_raises_error_message(self):
+        f = models.IntegerField()
+        self.assertRaises(ValidationError, f.clean, 'foo', None)
+        try:
+            f.clean('foo', None)
+        except ValidationError, e:
+            self.assertEqual(e.messages, [u"'foo' value must be an integer."])
+
+    def test_boolean_field_raises_error_message(self):
+        f = models.BooleanField()
+        self.assertRaises(ValidationError, f.clean, 'foo', None)
+        try:
+            f.clean('foo', None)
+        except ValidationError, e:
+            self.assertEqual(e.messages,
+                        [u"'foo' value must be either True or False."])
+
+    def test_float_field_raises_error_message(self):
+        f = models.FloatField()
+        self.assertRaises(ValidationError, f.clean, 'foo', None)
+        try:
+            f.clean('foo', None)
+        except ValidationError, e:
+            self.assertEqual(e.messages, [u"'foo' value must be a float."])
+
+    def test_decimal_field_raises_error_message(self):
+        f = models.DecimalField()
+        self.assertRaises(ValidationError, f.clean, 'foo', None)
+        try:
+            f.clean('foo', None)
+        except ValidationError, e:
+            self.assertEqual(e.messages,
+                        [u"'foo' value must be a decimal number."])
+
+    def test_null_boolean_field_raises_error_message(self):
+        f = models.NullBooleanField()
+        self.assertRaises(ValidationError, f.clean, 'foo', None)
+        try:
+            f.clean('foo', None)
+        except ValidationError, e:
+            self.assertEqual(e.messages,
+                        [u"'foo' value must be either None, True or False."])