Add MXCLABEField for Mexico

docs/changelog.rst

@@ -19,6 +19,8 @@ New fields for existing flavors:
   (`gh-151 <https://github.com/django/django-localflavor/pull/151>`_).
 - Added NLZipCodeField, NLProvinceField, NLSoFiNumberField, NLPhoneNumberField model fields.
   (`gh-152 <https://github.com/django/django-localflavor/pull/152>`_).
+- Added MXCLABEField form field.
+  (`gh-227 <https://github.com/django/django-localflavor/pull/227>`_).
 
 Modifications to existing flavors:
 

localflavor/mx/forms.py

@@ -163,6 +163,50 @@ def _has_inconvenient_word(self, rfc):
         return first_four in RFC_INCONVENIENT_WORDS
 
 
+class MXCLABEField(RegexField):
+    """This field validates a CLABE (Clave Bancaria Estandarizada).
+
+    A CLABE is a 18-digits long number. The first 6 digits denote bank and branch number.
+    The remaining 12 digits denote an account number, plus a verifying digit.
+
+    More info:
+    https://es.wikipedia.org/wiki/CLABE
+
+    .. versionadded:: 1.3
+    """
+
+    default_error_messages = {
+        'invalid': _('Enter a valid CLABE.'),
+        'invalid_checksum': _('Invalid checksum for CLABE.'),
+    }
+
+    def __init__(self, min_length=18, max_length=18, *args, **kwargs):
+        clabe_re = r'^\d{18}$'
+        clabe_re = re.compile(clabe_re)
+        super(MXCLABEField, self).__init__(clabe_re, min_length, max_length, *args, **kwargs)
+
+    def _checksum(self, value):
+        verification_digit = int(value[-1])
+        number = value[:-1]
+
+        ponderator = (3, 7, 1, 3, 7, 1, 3, 7, 1, 3, 7, 1, 3, 7, 1, 3, 7)
+
+        sum_remainder = sum(x * int(y) % 10 for x, y in zip(ponderator, number)) % 10
+
+        return verification_digit == (10 - sum_remainder) % 10
+
+    def clean(self, value):
+        value = super(MXCLABEField, self).clean(value)
+        if value in EMPTY_VALUES:
+            return ''
+        if not value.isdigit():
+            raise ValidationError(self.error_messages['invalid'])
+        if not self._checksum(value):
+            raise ValidationError(self.error_messages['invalid_checksum'])
+
+        return value
+
+
 class MXCURPField(RegexField):
     """
     A field that validates a Mexican Clave Única de Registro de Población.

localflavor/mx/models.py

@@ -1,6 +1,7 @@
 from django.db.models import CharField
 from django.utils.translation import ugettext_lazy as _
 
+from .forms import MXCLABEField as MXCLABEFormField
 from .forms import MXCURPField as MXCURPFormField
 from .forms import MXRFCField as MXRFCFormField
 from .forms import MXSocialSecurityNumberField as MXSocialSecurityNumberFormField
@@ -71,6 +72,28 @@ def formfield(self, **kwargs):
         return super(MXRFCField, self).formfield(**defaults)
 
 
+class MXCLABEField(CharField):
+    """
+    A model field that forms represent as a forms.MXCURPField field and
+    stores the value of a valid Mexican CLABE.
+    """
+    description = _("Mexican CLABE")
+
+    def __init__(self, *args, **kwargs):
+        kwargs['max_length'] = 18
+        super(MXCLABEField, self).__init__(*args, **kwargs)
+
+    def deconstruct(self):
+        name, path, args, kwargs = super(MXCLABEField, self).deconstruct()
+        del kwargs['max_length']
+        return name, path, args, kwargs
+
+    def formfield(self, **kwargs):
+        defaults = {'form_class': MXCLABEFormField}
+        defaults.update(kwargs)
+        return super(MXCLABEField, self).formfield(**defaults)
+
+
 class MXCURPField(CharField):
     """
     A model field that forms represent as a forms.MXCURPField field and

tests/test_mx/forms.py

@@ -7,4 +7,4 @@ class MXPersonProfileForm(ModelForm):
 
     class Meta:
         model = MXPersonProfile
-        fields = ('state', 'rfc', 'curp', 'zip_code', 'ssn')
+        fields = ('state', 'rfc', 'curp', 'zip_code', 'ssn', 'clabe')

tests/test_mx/models.py

@@ -1,6 +1,6 @@
 from django.db import models
-
-from localflavor.mx.models import MXCURPField, MXRFCField, MXSocialSecurityNumberField, MXStateField, MXZipCodeField
+from localflavor.mx.models import (MXCLABEField, MXCURPField, MXRFCField, MXSocialSecurityNumberField, MXStateField,
+                                   MXZipCodeField)
 
 
 class MXPersonProfile(models.Model):
@@ -9,3 +9,4 @@ class MXPersonProfile(models.Model):
     curp = MXCURPField()
     zip_code = MXZipCodeField()
     ssn = MXSocialSecurityNumberField()
+    clabe = MXCLABEField()

tests/test_mx/tests.py

@@ -2,8 +2,8 @@
 from __future__ import unicode_literals
 
 from django.test import TestCase
-
-from localflavor.mx.forms import MXCURPField, MXRFCField, MXSocialSecurityNumberField, MXStateSelect, MXZipCodeField
+from localflavor.mx.forms import (MXCLABEField, MXCURPField, MXRFCField, MXSocialSecurityNumberField, MXStateSelect,
+                                  MXZipCodeField)
 
 from .forms import MXPersonProfileForm
 
@@ -17,6 +17,7 @@ def setUp(self):
             'curp': 'toma880125hmnrrn02',
             'zip_code': '58120',
             'ssn': '53987417457',
+            'clabe': '032180000118359719'
         })
 
     def test_get_display_methods(self):
@@ -32,13 +33,15 @@ def test_errors(self):
             'curp': 'invalid curp',
             'zip_code': 'xxx',
             'ssn': 'invalid ssn',
+            'clabe': 'invalid clabe'
         })
         self.assertFalse(form.is_valid())
         self.assertEqual(form.errors['state'], ['Select a valid choice. Invalid state is not one of the available choices.'])
         self.assertEqual(form.errors['rfc'], ['Ensure this value has at least 12 characters (it has 11).', 'Enter a valid RFC.'])
         self.assertEqual(form.errors['curp'], ['Ensure this value has at least 18 characters (it has 12).', 'Enter a valid CURP.'])
         self.assertEqual(form.errors['zip_code'], ['Enter a valid zip code in the format XXXXX.'])
         self.assertEqual(form.errors['ssn'], ['Enter a valid Social Security Number.'])
+        self.assertEqual(form.errors['clabe'], ['Ensure this value has at least 18 characters (it has 13).', 'Enter a valid CLABE.'])
 
     def test_field_blank_option(self):
         """Test that the empty option is there."""
@@ -247,3 +250,28 @@ def test_MXSocialSecurityNumberField(self):
             '53563800130': error_checksum,
         }
         self.assertFieldOutput(MXSocialSecurityNumberField, valid, invalid)
+
+    def test_MXCLABEField(self):
+        error_format = ['Enter a valid CLABE.']
+        error_checksum = ['Invalid checksum for CLABE.']
+        valid = {
+            '032180000118359719': '032180000118359719',
+            '002115016003269411': '002115016003269411',
+            '435816798316429530': '435816798316429530',
+            '102211657483920119': '102211657483920119',
+            '002846375894578321': '002846375894578321',
+            '012276385238571288': '012276385238571288',
+            '633790823578925966': '633790823578925966',
+            '613137129494921910': '613137129494921910',
+            '108180637932589295': '108180637932589295',
+        }
+
+        invalid = {
+            'abc123def456-902-4': error_format,
+            '123456789123456789': error_checksum,
+            '123456237454589458': error_checksum,
+            '098765375925788389': error_checksum,
+            '042560735684818257': error_checksum,
+            '037027587179835981': error_checksum,
+        }
+        self.assertFieldOutput(MXCLABEField, valid, invalid)