Add Australian Company Number validator

docs/authors.rst

@@ -10,6 +10,7 @@ Authors
 * Alex Gaynor
 * Alex Hill
 * Alex Zhang
+* Alexey Kotlyarov
 * Alix Martineau
 * Alonisser
 * Andreas Pelme

docs/changelog.rst

@@ -14,6 +14,8 @@ New fields for existing flavors:
 
 - Added NOBankAccountNumber form field.
   (`gh-275 <https://github.com/django/django-localflavor/pull/275>`_)
+- Added AUCompanyNumberField model and form field.
+  (`gh-278 <https://github.com/django/django-localflavor/pull/278>`_)
 
 Modifications to existing flavors:
 

localflavor/au/forms.py

@@ -13,7 +13,7 @@
 from localflavor.generic.forms import DeprecatedPhoneNumberFormFieldMixin
 
 from .au_states import STATE_CHOICES
-from .validators import AUBusinessNumberFieldValidator, AUTaxFileNumberFieldValidator
+from .validators import AUBusinessNumberFieldValidator, AUCompanyNumberFieldValidator, AUTaxFileNumberFieldValidator
 
 PHONE_DIGITS_RE = re.compile(r'^(\d{10})$')
 
@@ -88,6 +88,28 @@ def prepare_value(self, value):
         return '{} {} {} {}'.format(spaceless[:2], spaceless[2:5], spaceless[5:8], spaceless[8:])
 
 
+class AUCompanyNumberField(CharField):
+    """
+    A form field that validates input as an Australian Company Number (ACN).
+
+    .. versionadded:: 1.5
+    """
+
+    default_validators = [AUCompanyNumberFieldValidator()]
+
+    def to_python(self, value):
+        value = super(AUCompanyNumberField, self).to_python(value)
+        return value.upper().replace(' ', '')
+
+    def prepare_value(self, value):
+        """Format the value for display."""
+        if value is None:
+            return value
+
+        spaceless = ''.join(value.split())
+        return '{} {} {}'.format(spaceless[:3], spaceless[3:6], spaceless[6:])
+
+
 class AUTaxFileNumberField(CharField):
     """
     A form field that validates input as an Australian Tax File Number (TFN).

localflavor/au/models.py

@@ -4,7 +4,7 @@
 from localflavor.generic.models import DeprecatedPhoneNumberField
 from . import forms
 from .au_states import STATE_CHOICES
-from .validators import AUBusinessNumberFieldValidator, AUTaxFileNumberFieldValidator
+from .validators import AUBusinessNumberFieldValidator, AUCompanyNumberFieldValidator, AUTaxFileNumberFieldValidator
 
 
 class AUStateField(CharField):
@@ -91,6 +91,36 @@ def to_python(self, value):
         return value
 
 
+class AUCompanyNumberField(CharField):
+    """
+    A model field that checks that the value is a valid Australian Company Number (ACN).
+
+    .. versionadded:: 1.5
+    """
+
+    description = _("Australian Company Number")
+
+    validators = [AUCompanyNumberFieldValidator()]
+
+    def __init__(self, *args, **kwargs):
+        kwargs['max_length'] = 9
+        super(AUCompanyNumberField, self).__init__(*args, **kwargs)
+
+    def formfield(self, **kwargs):
+        defaults = {'form_class': forms.AUCompanyNumberField}
+        defaults.update(kwargs)
+        return super(AUCompanyNumberField, self).formfield(**defaults)
+
+    def to_python(self, value):
+        """Ensure the ACN is stored without spaces."""
+        value = super(AUCompanyNumberField, self).to_python(value)
+
+        if value is not None:
+            return ''.join(value.split())
+
+        return value
+
+
 class AUTaxFileNumberField(CharField):
     """
     A model field that checks that the value is a valid Tax File Number (TFN).

localflavor/au/validators.py

@@ -51,6 +51,49 @@ def __call__(self, value):
             raise ValidationError(self.error_message)
 
 
+class AUCompanyNumberFieldValidator(RegexValidator):
+    """
+    Validation for Australian Company Numbers.
+
+    .. versionadded:: 1.5
+    """
+
+    error_message = _('Enter a valid ACN.')
+
+    def __init__(self):
+        nine_digits = '^\d{9}$'
+        super(AUCompanyNumberFieldValidator, self).__init__(
+            regex=nine_digits, message=self.error_message)
+
+    def _is_valid(self, value):
+        """
+        Return whether the given value is a valid ACN.
+
+        See http://www.clearwater.com.au/code/acn for a description of the
+        validation algorithm.
+
+        """
+        digits = [int(i) for i in list(value)]
+
+        # 1. Multiply each digit by its weighting factor.
+        weighting_factors = [8, 7, 6, 5, 4, 3, 2, 1]
+        weighted = [digit * weight for digit, weight in zip(digits, weighting_factors)]
+
+        # 3. Sum the resulting values.
+        total = sum(weighted)
+
+        # 4. Calculate the check digit
+        check = (10 - total % 10) % 10
+
+        # 5. Check against the last digit
+        return check == digits[8]
+
+    def __call__(self, value):
+        super(AUCompanyNumberFieldValidator, self).__call__(value)
+        if not self._is_valid(value):
+            raise ValidationError(self.error_message)
+
+
 class AUTaxFileNumberFieldValidator(RegexValidator):
     """
     Validation for Australian Tax File Numbers.

tests/test_au/models.py

@@ -1,7 +1,7 @@
 from django.db import models
 
-from localflavor.au.models import (AUBusinessNumberField, AUPhoneNumberField, AUPostCodeField, AUStateField,
-                                   AUTaxFileNumberField)
+from localflavor.au.models import (AUBusinessNumberField, AUCompanyNumberField, AUPhoneNumberField, AUPostCodeField,
+                                   AUStateField, AUTaxFileNumberField)
 
 
 class AustralianPlace(models.Model):
@@ -14,4 +14,5 @@ class AustralianPlace(models.Model):
     phone = AUPhoneNumberField(blank=True)
     name = models.CharField(max_length=20)
     abn = AUBusinessNumberField()
+    acn = AUCompanyNumberField()
     tfn = AUTaxFileNumberField()

tests/test_au/tests.py

@@ -6,7 +6,8 @@
 from django.test import TestCase
 
 from localflavor.au import forms, models
-from localflavor.au.validators import AUBusinessNumberFieldValidator, AUTaxFileNumberFieldValidator
+from localflavor.au.validators import (AUBusinessNumberFieldValidator, AUCompanyNumberFieldValidator,
+                                       AUTaxFileNumberFieldValidator)
 
 from .forms import AustralianPlaceForm
 from .models import AustralianPlace
@@ -195,6 +196,56 @@ def test_raises_error_for_invalid_abn(self):
         self.assertRaises(ValidationError, lambda: validator(invalid_abn))
 
 
+class AULocalFlavorAUCompanyNumberFieldValidatorTests(TestCase):
+
+    def test_no_error_for_a_valid_acn(self):
+        """Test a valid ACN does not cause an error."""
+        valid_acn = '604327504'
+
+        validator = AUCompanyNumberFieldValidator()
+
+        validator(valid_acn)
+
+    def test_raises_error_for_acn_containing_a_letter(self):
+        """Test an ACN containing a letter is invalid."""
+        invalid_acn = '60432750A'
+
+        validator = AUCompanyNumberFieldValidator()
+
+        self.assertRaises(ValidationError, lambda: validator(invalid_acn))
+
+    def test_raises_error_for_too_short_acn(self):
+        """Test an ACN with fewer than nine digits is invalid."""
+        invalid_acn = '60432750'
+
+        validator = AUCompanyNumberFieldValidator()
+
+        self.assertRaises(ValidationError, lambda: validator(invalid_acn))
+
+    def test_raises_error_for_too_long_acn(self):
+        """Test an ACN with more than nine digits is invalid."""
+        invalid_acn = '6043275040'
+        validator = AUCompanyNumberFieldValidator()
+        self.assertRaises(ValidationError, lambda: validator(invalid_acn))
+
+    def test_raises_error_for_whitespace(self):
+        """Test an ACN can be valid when it contains whitespace."""
+        # NB: Form field should strip the whitespace before regex valdation is run.
+        invalid_acn = '604 327 504'
+
+        validator = AUCompanyNumberFieldValidator()
+
+        self.assertRaises(ValidationError, lambda: validator(invalid_acn))
+
+    def test_raises_error_for_invalid_acn(self):
+        """Test that an ACN must pass the ATO's validation algorithm."""
+        invalid_acn = '604327509'
+
+        validator = AUCompanyNumberFieldValidator()
+
+        self.assertRaises(ValidationError, lambda: validator(invalid_acn))
+
+
 class AULocalFlavorAUTaxFileNumberFieldValidatorTests(TestCase):
 
     def test_no_error_for_a_valid_tfn(self):