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Add European Community (EC) Number #422

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7f503d8
Add European Community (EC) Number
weberdak Nov 11, 2023
a8e6d16
Add tests for single hyphen and non-numeric characters
weberdak Nov 12, 2023
97e24e7
Remove redundant hyphen check
weberdak Nov 12, 2023
fc4480c
Add newline and remove trailing whitespace
weberdak Nov 12, 2023
e082341
Remove typo
weberdak Nov 12, 2023
c346a41
Merge branch 'arthurdejong:master' into master
weberdak Nov 15, 2023
81007b0
Handle check digit of 10
weberdak Nov 19, 2023
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84 changes: 84 additions & 0 deletions stdnum/eu/ecnumber.py
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# ecnumber.py - functions for handling European Community Numbers

# Copyright (C) 2023 Daniel Weber
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301 USA

"""EC Number (European Community Number).

The EC Number is a unique seven-digit number assigned to chemical substances
for regulatory purposes within the European Union by the European Commision.

More information:

* https://en.wikipedia.org/wiki/European_Community_number

>>> validate('200-001-8')
'200-001-8'
>>> validate('200-001-9')
Traceback (most recent call last):
...
InvalidChecksum: ...
>>> validate('20-0001-8')
Traceback (most recent call last):
...
InvalidFormat: ...
"""

import re

from stdnum.exceptions import *
from stdnum.util import clean


_ec_number_re = re.compile(r'^[0-9]{3}-[0-9]{3}-[0-9]$')


def compact(number):
"""Convert the number to the minimal representation."""
number = clean(number, ' ').strip()
if '-' not in number:
number = '-'.join((number[:3], number[3:6], number[6:]))
return number


def calc_check_digit(number):
"""Calculate the check digit for the number. The passed number should not
have the check digit included. In instances where the check digit is
'10', the check digit is set to '1' and the number is considered."""
number = number.replace('-', '')
return str(
sum((i + 1) * int(n) for i, n in enumerate(number)) % 11)[0]


def validate(number):
"""Check if the number provided is a valid EC Number."""
number = compact(number)
if not len(number) == 9:
raise InvalidLength()
if not _ec_number_re.match(number):
raise InvalidFormat()
if number[-1] != calc_check_digit(number[:-1]):
raise InvalidChecksum()
return number


def is_valid(number):
"""Check if the number provided is a valid EC Number."""
try:
return bool(validate(number))
except ValidationError:
return False
199 changes: 199 additions & 0 deletions tests/test_eu_ecnumber.doctest
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test_eu_ecnumber.doctest - more detailed doctests for the stdnum.eu.ecnumber module

Copyright (C) 2023 Daniel Weber

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA


This file contains more detailed doctests for the stdnum.eu.ecnumber module. It
contains some corner case tests and tries to validate numbers that have been
found online.

>>> from stdnum.eu import ecnumber
>>> from stdnum.exceptions import *


EC Numbers always include separators and will be introduced if they
are not present. Validation will fail if separators are in the incorrect
place.

>>> ecnumber.validate('200-112-1')
'200-112-1'
>>> ecnumber.validate('2001121')
'200-112-1'
>>> ecnumber.validate('20-0112-1')
Traceback (most recent call last):
...
InvalidFormat: ...
>>> ecnumber.validate('2000112-1')
Traceback (most recent call last):
...
InvalidFormat: ...


The number should only have two separators.

>>> ecnumber.validate('20--112-1')
Traceback (most recent call last):
...
InvalidFormat: ...


Only numeric characters between separators.

>>> ecnumber.validate('20A-112-1')
Traceback (most recent call last):
...
InvalidFormat: ...


EC Numbers are always nine characters long (including hyphens).

>>> ecnumber.validate('2000-112-1')
Traceback (most recent call last):
...
InvalidLength: ...
>>> ecnumber.validate('20001121')
Traceback (most recent call last):
...
InvalidLength: ...
>>> ecnumber.validate('201121')
Traceback (most recent call last):
...
InvalidLength: ...


The final character must have the correct check digit.

>>> ecnumber.validate('200-112-2')
Traceback (most recent call last):
...
InvalidChecksum: ...
>>> ecnumber.validate('2001122')
Traceback (most recent call last):
...
InvalidChecksum: ...


These are randomly selected from the EC Inventory should be valid EC Numbers.

>>> numbers = '''
...
... 257-228-0
... 207-296-2
... 297-119-5
... 287-900-9
... 271-104-3
... 280-851-4
... 281-919-6
... 252-552-9
... 215-429-0
... 249-469-5
... 421-750-9
... 301-916-6
... 217-931-5
... 295-191-2
... 207-952-8
... 211-043-1
... 262-758-0
... 255-597-2
... 255-524-4
... 226-307-1
... 276-796-0
... 274-741-5
... 250-046-2
... 287-761-4
... 200-662-2
... 200-897-0
... 250-140-3
... 222-729-5
... 212-948-4
... 239-367-9
... 249-213-2
... 263-543-4
... 259-660-5
... 254-324-4
... 241-289-5
... 228-426-4
... 207-631-2
... 245-704-0
... 282-848-3
... 204-282-8
... 284-690-0
... 282-944-5
... 302-175-1
... 251-412-4
... 257-308-5
... 220-575-3
... 249-244-1
... 266-556-3
... 288-360-7
... 266-708-9
... 221-531-6
... 274-747-8
... 238-769-1
... 251-186-7
... 254-323-9
... 247-214-2
... 304-902-8
... 307-415-9
... 256-980-7
... 296-057-6
... 222-700-7
... 223-550-5
... 239-530-4
... 219-941-5
... 216-155-4
... 236-325-1
... 244-886-9
... 248-170-7
... 203-499-5
... 280-279-5
... 267-064-1
... 280-947-6
... 266-597-7
... 281-719-9
... 250-478-1
... 243-154-6
... 271-556-1
... 263-157-6
... 301-691-4
... 274-112-5
... 302-331-9
... 235-556-5
... 244-556-4
... 217-593-9
... 206-777-4
... 286-712-4
... 414-380-4
... 242-807-2
... 500-464-9
... 252-796-6
... 304-512-8
... 307-269-6
... 238-475-3
... 304-680-2
... 273-972-9
... 297-362-7
... 233-748-3
... 307-692-6
... 300-706-1
... 310-159-0
... 424-870-1
...
... '''
>>> [x for x in numbers.splitlines() if x and not ecnumber.is_valid(x)]
[]