Fixed #24636 -- Added model field validation for decimal places and max digits. (75ed5900) · Commits · Dom Sekotill / django

django/core/validators.py

+69 −0

Original line number	Diff line number	Diff line
		@@ -346,3 +346,72 @@ class MaxLengthValidator(BaseValidator):
		'Ensure this value has at most %(limit_value)d characters (it has %(show_value)d).',
		'limit_value')
		code = 'max_length'


		@deconstructible
		class DecimalValidator(object):
		"""
		Validate that the input does not exceed the maximum number of digits
		expected, otherwise raise ValidationError.
		"""
		messages = {
		'max_digits': ungettext_lazy(
		'Ensure that there are no more than %(max)s digit in total.',
		'Ensure that there are no more than %(max)s digits in total.',
		'max'
		),
		'max_decimal_places': ungettext_lazy(
		'Ensure that there are no more than %(max)s decimal place.',
		'Ensure that there are no more than %(max)s decimal places.',
		'max'
		),
		'max_whole_digits': ungettext_lazy(
		'Ensure that there are no more than %(max)s digit before the decimal point.',
		'Ensure that there are no more than %(max)s digits before the decimal point.',
		'max'
		),
		}

		def __init__(self, max_digits, decimal_places):
		self.max_digits = max_digits
		self.decimal_places = decimal_places

		def __call__(self, value):
		digit_tuple, exponent = value.as_tuple()[1:]
		decimals = abs(exponent)
		# digit_tuple doesn't include any leading zeros.
		digits = len(digit_tuple)
		if decimals > digits:
		# We have leading zeros up to or past the decimal point. Count
		# everything past the decimal point as a digit. We do not count
		# 0 before the decimal point as a digit since that would mean
		# we would not allow max_digits = decimal_places.
		digits = decimals
		whole_digits = digits - decimals

		if self.max_digits is not None and digits > self.max_digits:
		raise ValidationError(
		self.messages['max_digits'],
		code='max_digits',
		params={'max': self.max_digits},
		)
		if self.decimal_places is not None and decimals > self.decimal_places:
		raise ValidationError(
		self.messages['max_decimal_places'],
		code='max_decimal_places',
		params={'max': self.decimal_places},
		)
		if (self.max_digits is not None and self.decimal_places is not None
		and whole_digits > (self.max_digits - self.decimal_places)):
		raise ValidationError(
		self.messages['max_whole_digits'],
		code='max_whole_digits',
		params={'max': (self.max_digits - self.decimal_places)},
		)

		def __eq__(self, other):
		return (
		isinstance(other, self.__class__) and
		self.max_digits == other.max_digits and
		self.decimal_places == other.decimal_places
		)

django/db/models/fields/init.py

+6 −0

Original line number	Diff line number	Diff line
		@@ -1578,6 +1578,12 @@ class DecimalField(Field):
		]
		return []

		@cached_property
		def validators(self):
		return super(DecimalField, self).validators + [
		validators.DecimalValidator(self.max_digits, self.decimal_places)
		]

		def deconstruct(self):
		name, path, args, kwargs = super(DecimalField, self).deconstruct()
		if self.max_digits is not None:

django/forms/fields.py

+1 −44

Original line number	Diff line number	Diff line
		@@ -334,23 +334,12 @@ class FloatField(IntegerField):
		class DecimalField(IntegerField):
		default_error_messages = {
		'invalid': _('Enter a number.'),
		'max_digits': ungettext_lazy(
		'Ensure that there are no more than %(max)s digit in total.',
		'Ensure that there are no more than %(max)s digits in total.',
		'max'),
		'max_decimal_places': ungettext_lazy(
		'Ensure that there are no more than %(max)s decimal place.',
		'Ensure that there are no more than %(max)s decimal places.',
		'max'),
		'max_whole_digits': ungettext_lazy(
		'Ensure that there are no more than %(max)s digit before the decimal point.',
		'Ensure that there are no more than %(max)s digits before the decimal point.',
		'max'),
		}

		def __init__(self, max_value=None, min_value=None, max_digits=None, decimal_places=None, args, *kwargs):
		self.max_digits, self.decimal_places = max_digits, decimal_places
		super(DecimalField, self).__init__(max_value, min_value, args, *kwargs)
		self.validators.append(validators.DecimalValidator(max_digits, decimal_places))

		def to_python(self, value):
		"""
		@@ -379,38 +368,6 @@ class DecimalField(IntegerField):
		# isn't equal to itself, so we can use this to identify NaN
		if value != value or value == Decimal("Inf") or value == Decimal("-Inf"):
		raise ValidationError(self.error_messages['invalid'], code='invalid')
		sign, digittuple, exponent = value.as_tuple()
		decimals = abs(exponent)
		# digittuple doesn't include any leading zeros.
		digits = len(digittuple)
		if decimals > digits:
		# We have leading zeros up to or past the decimal point. Count
		# everything past the decimal point as a digit. We do not count
		# 0 before the decimal point as a digit since that would mean
		# we would not allow max_digits = decimal_places.
		digits = decimals
		whole_digits = digits - decimals

		if self.max_digits is not None and digits > self.max_digits:
		raise ValidationError(
		self.error_messages['max_digits'],
		code='max_digits',
		params={'max': self.max_digits},
		)
		if self.decimal_places is not None and decimals > self.decimal_places:
		raise ValidationError(
		self.error_messages['max_decimal_places'],
		code='max_decimal_places',
		params={'max': self.decimal_places},
		)
		if (self.max_digits is not None and self.decimal_places is not None
		and whole_digits > (self.max_digits - self.decimal_places)):
		raise ValidationError(
		self.error_messages['max_whole_digits'],
		code='max_whole_digits',
		params={'max': (self.max_digits - self.decimal_places)},
		)
		return value

		def widget_attrs(self, widget):
		attrs = super(DecimalField, self).widget_attrs(widget)

docs/ref/validators.txt

+16 −0

Original line number	Diff line number	Diff line
		@@ -281,3 +281,19 @@ to, or in lieu of custom ``field.clean()`` methods.
		.. versionchanged:: 1.8

		The ``message`` parameter was added.

		``DecimalValidator``
		--------------------

		.. class:: DecimalValidator(max_digits, decimal_places)

		.. versionadded:: 1.9

		Raises :exc:`~django.core.exceptions.ValidationError` with the following
		codes:

		- ``'max_digits'`` if the number of digits is larger than ``max_digits``.
		- ``'max_decimal_places'`` if the number of decimals is larger than
		``decimal_places``.
		- ``'max_whole_digits'`` if the number of whole digits is larger than
		the difference between ``max_digits`` and ``decimal_places``.

tests/model_fields/tests.py

+18 −0

Original line number	Diff line number	Diff line
		@@ -165,6 +165,24 @@ class DecimalFieldTests(test.TestCase):
		# This should not crash. That counts as a win for our purposes.
		Foo.objects.filter(d__gte=100000000000)

		def test_max_digits_validation(self):
		field = models.DecimalField(max_digits=2)
		expected_message = validators.DecimalValidator.messages['max_digits'] % {'max': 2}
		with self.assertRaisesMessage(ValidationError, expected_message):
		field.clean(100, None)

		def test_max_decimal_places_validation(self):
		field = models.DecimalField(decimal_places=1)
		expected_message = validators.DecimalValidator.messages['max_decimal_places'] % {'max': 1}
		with self.assertRaisesMessage(ValidationError, expected_message):
		field.clean(Decimal('0.99'), None)

		def test_max_whole_digits_validation(self):
		field = models.DecimalField(max_digits=3, decimal_places=1)
		expected_message = validators.DecimalValidator.messages['max_whole_digits'] % {'max': 2}
		with self.assertRaisesMessage(ValidationError, expected_message):
		field.clean(Decimal('999'), None)


		class ForeignKeyTests(test.TestCase):
		def test_callable_default(self):