Improve fi-ssn validator (#97)

* Fi-ssn validator: checksum must be upper case

* Fi-ssn validator: better validation for the date

* Fi-ssn validator: Implement serial validation

Make fi-ssn validator by default accept all valid serials, meaning
serials in range 2 - 999. Also add an option to not allow temporal
serials that are in the range 900 - 999.

Author: quantus

tests/i18n/test_fi.py

@@ -25,9 +25,11 @@ def test_returns_failed_validation_on_invalid_email(value):
 
 
 @pytest.mark.parametrize(('value',), [
+    ('010190-002R',),
     ('010101-0101',),
     ('010101+0101',),
     ('010101A0101',),
+    ('010190-900P',),
 ])
 def test_returns_true_on_valid_ssn(value):
     assert fi_ssn(value)
@@ -36,10 +38,22 @@ def test_returns_true_on_valid_ssn(value):
 @pytest.mark.parametrize(('value',), [
     (None,),
     ('',),
+    ('010190-001P',),  # Too low serial
+    ('010190-000N',),  # Too low serial
+    ('000190-0023',),  # Invalid day
+    ('010090-002X',),  # Invalid month
+    ('010190-002r',),  # Invalid checksum
     ('101010-0102',),
     ('10a010-0101',),
     ('101010-0\xe401',),
     ('101010b0101',)
 ])
 def test_returns_failed_validation_on_invalid_ssn(value):
     assert isinstance(fi_ssn(value), ValidationFailure)
+
+
+def test_returns_failed_validation_on_temporal_ssn_when_not_allowed():
+    assert isinstance(
+        fi_ssn('010190-900P', allow_temporal_ssn=False),
+        ValidationFailure
+    )

validators/i18n/fi.py

@@ -6,13 +6,13 @@
 ssn_checkmarks = '0123456789ABCDEFHJKLMNPRSTUVWXY'
 ssn_pattern = re.compile(
     r"""^
-    (?P<date>([0-2]\d|3[01])
-    (0\d|1[012])
+    (?P<date>(0[1-9]|[1-2]\d|3[01])
+    (0[1-9]|1[012])
     (\d{{2}}))
     [A+-]
     (?P<serial>(\d{{3}}))
     (?P<checksum>[{checkmarks}])$""".format(checkmarks=ssn_checkmarks),
-    re.VERBOSE | re.IGNORECASE
+    re.VERBOSE
 )
 
 
@@ -52,7 +52,7 @@ def fi_business_id(business_id):
 
 
 @validator
-def fi_ssn(ssn):
+def fi_ssn(ssn, allow_temporal_ssn=True):
     """
     Validate a Finnish Social Security Number.
 
@@ -67,11 +67,16 @@ def fi_ssn(ssn):
         True
 
         >>> fi_ssn('101010-0102')
-        ValidationFailure(func=fi_ssn, args={'ssn': '101010-0102'})
+        ValidationFailure(func=fi_ssn, args=...)
 
     .. versionadded:: 0.5
 
     :param ssn: Social Security Number to validate
+    :param allow_temporal_ssn:
+        Whether to accept temporal SSN numbers. Temporal SSN numbers are the
+        ones where the serial is in the range [900-999]. By default temporal
+        SSN numbers are valid.
+
     """
     if not ssn:
         return False
@@ -82,6 +87,8 @@ def fi_ssn(ssn):
     gd = result.groupdict()
     checksum = int(gd['date'] + gd['serial'])
     return (
+        int(gd['serial']) >= 2 and
+        (allow_temporal_ssn or int(gd['serial']) <= 899) and
         ssn_checkmarks[checksum % len(ssn_checkmarks)] ==
-        gd['checksum'].upper()
+        gd['checksum']
     )