feat: add french i18n validation (#308)

* feat: add french i18n validation

---------

Co-authored-by: Jovial Joe Jayarson <jovial7joe@hotmail.com>

Author: imperosol

src/validators/__init__.py

@@ -9,7 +9,7 @@
 from .email import email
 from .hashes import md5, sha1, sha224, sha256, sha512
 from .hostname import hostname
-from .i18n import es_cif, es_doi, es_nie, es_nif, fi_business_id, fi_ssn
+from .i18n import es_cif, es_doi, es_nie, es_nif, fi_business_id, fi_ssn, fr_department, fr_ssn
 from .iban import iban
 from .ip_address import ipv4, ipv6
 from .length import length
@@ -57,6 +57,8 @@
     "es_nif",
     "fi_business_id",
     "fi_ssn",
+    "fr_department",
+    "fr_ssn",
     # ...
     "iban",
     # ip addresses

src/validators/i18n/__init__.py

@@ -5,5 +5,15 @@
 # local
 from .es import es_cif, es_doi, es_nie, es_nif
 from .fi import fi_business_id, fi_ssn
+from .fr import fr_department, fr_ssn
 
-__all__ = ("fi_business_id", "fi_ssn", "es_cif", "es_doi", "es_nie", "es_nif")
+__all__ = (
+    "fi_business_id",
+    "fi_ssn",
+    "es_cif",
+    "es_doi",
+    "es_nie",
+    "es_nif",
+    "fr_department",
+    "fr_ssn",
+)

src/validators/i18n/fr.py

@@ -0,0 +1,127 @@
+"""France."""
+
+# standard
+from functools import lru_cache
+import re
+import typing
+
+# local
+from validators.utils import validator
+
+
+@lru_cache
+def _ssn_pattern():
+    """SSN Pattern."""
+    return re.compile(
+        r"^([1,2])"  # gender (1=M, 2=F)
+        r"\s(\d{2})"  # year of birth
+        r"\s(0[1-9]|1[0-2])"  # month of birth
+        r"\s(\d{2,3}|2[A,B])"  # department of birth
+        r"\s(\d{2,3})"  # town of birth
+        r"\s(\d{3})"  # registration number
+        r"(?:\s(\d{2}))?$",  # control key (may or may not be provided)
+        re.VERBOSE,
+    )
+
+
+@validator
+def fr_department(value: typing.Union[str, int]):
+    """Validate a french department number.
+
+    Examples:
+        >>> fr_department(20)  # can be an integer
+        # Output: True
+        >>> fr_department("20")
+        # Output: True
+        >>> fr_department("971")  # Guadeloupe
+        # Output: True
+        >>> fr_department("00")
+        # Output: ValidationError(func=fr_department, args=...)
+        >>> fr_department('2A')  # Corsica
+        # Output: True
+        >>> fr_department('2B')
+        # Output: True
+        >>> fr_department('2C')
+        # Output: ValidationError(func=fr_department, args=...)
+
+    Args:
+        value:
+            French department number to validate.
+
+    Returns:
+        (Literal[True]):
+            If `value` is a valid french department number.
+        (ValidationError):
+            If `value` is an invalid french department number.
+
+    > *New in version 0.23.0*.
+    """
+    if not value:
+        return False
+    if isinstance(value, str):
+        if value in ("2A", "2B"):  # Corsica
+            return True
+        try:
+            value = int(value)
+        except ValueError:
+            return False
+    return 1 <= value <= 19 or 21 <= value <= 95 or 971 <= value <= 976  # Overseas departments
+
+
+@validator
+def fr_ssn(value: str):
+    """Validate a french Social Security Number.
+
+    Each french citizen has a distinct Social Security Number.
+    For more information see [French Social Security Number][1] (sadly unavailable in english).
+
+    [1]: https://fr.wikipedia.org/wiki/Num%C3%A9ro_de_s%C3%A9curit%C3%A9_sociale_en_France
+
+    Examples:
+        >>> fr_ssn('1 84 12 76 451 089 46')
+        # Output: True
+        >>> fr_ssn('1 84 12 76 451 089')  # control key is optional
+        # Output: True
+        >>> fr_ssn('3 84 12 76 451 089 46')  # wrong gender number
+        # Output: ValidationError(func=fr_ssn, args=...)
+        >>> fr_ssn('1 84 12 76 451 089 47')  # wrong control key
+        # Output: ValidationError(func=fr_ssn, args=...)
+
+    Args:
+        value:
+            French Social Security Number string to validate.
+
+    Returns:
+        (Literal[True]):
+            If `value` is a valid french Social Security Number.
+        (ValidationError):
+            If `value` is an invalid french Social Security Number.
+
+    > *New in version 0.23.0*.
+    """
+    if not value:
+        return False
+    matched = re.match(_ssn_pattern(), value)
+    if not matched:
+        return False
+    groups = list(matched.groups())
+    control_key = groups[-1]
+    department = groups[3]
+    if department != "99" and not fr_department(department):
+        # 99 stands for foreign born people
+        return False
+    if control_key is None:
+        # no control key provided, no additional check needed
+        return True
+    if len(department) == len(groups[4]):
+        # if the department number is 3 digits long (overseas departments),
+        # the town number must be 2 digits long
+        # and vice versa
+        return False
+    if department in ("2A", "2B"):
+        # Corsica's department numbers are not in the same range as the others
+        # thus 2A and 2B are replaced by 19 and 18 respectively to compute the control key
+        groups[3] = "19" if department == "2A" else "18"
+    # the control key is valid if it is equal to 97 - (the first 13 digits modulo 97)
+    digits = int("".join(groups[:-1]))
+    return int(control_key) == (97 - (digits % 97))

tests/i18n/test_fr.py

@@ -0,0 +1,86 @@
+"""Test French validators."""
+
+# standard
+from typing import Union
+
+# external
+import pytest
+
+# local
+from validators import ValidationError
+from validators.i18n.fr import fr_department, fr_ssn
+
+
+@pytest.mark.parametrize(
+    ("value",),
+    [
+        ("1 84 12 76 451 089 46",),
+        ("1 84 12 76 451 089",),  # control key is optional
+        ("2 99 05 75 202 818 97",),
+        ("2 99 05 75 202 817 01",),
+        ("2 99 05 2A 202 817 58",),
+        ("2 99 05 2B 202 817 85",),
+        ("2 99 05 971 12 817 70",),
+    ],
+)
+def test_returns_true_on_valid_ssn(value: str):
+    """Test returns true on valid ssn."""
+    assert fr_ssn(value)
+
+
+@pytest.mark.parametrize(
+    ("value",),
+    [
+        (None,),
+        ("",),
+        ("3 84 12 76 451 089 46",),  # wrong gender number
+        ("1 84 12 76 451 089 47",),  # wrong control key
+        ("1 84 00 76 451 089",),  # invalid month
+        ("1 84 13 76 451 089",),  # invalid month
+        ("1 84 12 00 451 089",),  # invalid department
+        ("1 84 12 2C 451 089",),
+        ("1 84 12 98 451 089",),  # invalid department
+        # ("1 84 12 971 451 089",), # ?
+    ],
+)
+def test_returns_failed_validation_on_invalid_ssn(value: str):
+    """Test returns failed validation on invalid_ssn."""
+    assert isinstance(fr_ssn(value), ValidationError)
+
+
+@pytest.mark.parametrize(
+    ("value",),
+    [
+        ("01",),
+        ("2A",),  # Corsica
+        ("2B",),
+        (14,),
+        ("95",),
+        ("971",),
+        (971,),
+    ],
+)
+def test_returns_true_on_valid_department(value: Union[str, int]):
+    """Test returns true on valid department."""
+    assert fr_department(value)
+
+
+@pytest.mark.parametrize(
+    ("value",),
+    [
+        (None,),
+        ("",),
+        ("00",),
+        (0,),
+        ("2C",),
+        ("97",),
+        ("978",),
+        ("98",),
+        ("96",),
+        ("20",),
+        (20,),
+    ],
+)
+def test_returns_failed_validation_on_invalid_department(value: Union[str, int]):
+    """Test returns failed validation on invalid department."""
+    assert isinstance(fr_department(value), ValidationError)