Refactor Spain country handler to support Natural Persons without DNI or NIE and Non-Natural Persons TIN formats

[alphp]

This PR

• Refactor Spanish country handler to support Natural Persons without DNI or NIE and Non-Natural Persons TIN formats
• Documentation

Spanish Natural Persons without DNI or NIE and Non-Natural Persons TIN formats:

Format	Explanation	Comments	Example
K9999999C	Letter K + 7 digits + 1 Control character	Resident Spaniards under 14 without DNI	K0867756I
L9999999C	Letter L + 7 digits + 1 Control character	Non-resident Spaniards without DNI	L2812345C
M9999999C	Letter M + 7 digits + 1 Control character	Foreigners without NIE	M2812345C
L9999999C	1 Letter + 7 digits + 1 Control character	Non-Natural Persons	P2009300A

[drupol]

Hello,

Are these changes from somewhere? Can you please provide the documentation?

In the TIN specifications hasn't been updated since 2019, do you have an updated specification?

Thanks!

[alphp]

I have refactored the code according to the validation that I created in 2015 and with which I have validated hundreds of TINs from public organizations in Spain.
https://lab.fawno.com/2015/08/27/validacion-de-cif-nif/

The code is based on the information collected in the Spanish Wikipedia:
https://es.wikipedia.org/wiki/C%C3%B3digo_de_identificaci%C3%B3n_fiscal
https://es.wikipedia.org/wiki/N%C3%BAmero_de_identificaci%C3%B3n_fiscal

Right now I do not have official sources on the validation of Spanish TINs. If I find something I will share it here.

[alphp]

The 'P2009300A' corresponds to the City Council of Mendaro (Gipuzkoa, Spain) and is one of the many CIFs that did not validate the current code:
https://www.euskadi.eus/ac70cPublicidadWar/trazabilidad/336188?idioma=es&R01HNoPortal=true
The CIF 'B05327986' is based on a real company code, but modified so that, although valid, it does not correspond to any company.

Estos son validadores online que validan correctamente los TIN con los que he tenido problemas:
https://factura.city/validar-vat
https://www.validardni.es/

[drupol]

Let's be consistent here to make sure that the message you're trying to tell me is well understood.

From what I understand:

1. You've created a Spain TIN validator, used hundreds of times.
2. Its code is based on Wikipedia
3. You would like to implement updates so that more Spain TINs can be supported?

Questions:

1. Is CIF equals TIN ? Can you please clarify that?
2. Can we please continue the conversation in English. I don't really speak Spanish even though I think I have understood what you meant.

Thoughts:

Regarding making changes, I wish I could have official sources to implement these changes, even though they seem totally correct. Do you know where we can find that documentation?

[alphp]

The Código de Identificación Fiscal (CIF, tax identification code) was the name given to TINs in Spain from 1975 to 2008.
https://www.boe.es/buscar/doc.php?id=BOE-A-1975-21698
https://www.boe.es/buscar/act.php?id=BOE-A-2008-3580

For historical reasons, we commonly call the TIN of a company, organization or public entity as CIF.

There are three algorithms:

1. For natural persons (real people): Spain::PATTERN_1
   https://www.interior.gob.es/opencms/ca/servicios-al-ciudadano/tramites-y-gestiones/dni/calculo-del-digito-de-control-del-nif-nie/
2. For legal entities (companies, organizations and public entities):
   a. Ended in control digit (0-9): Spain::PATTERN_2
   b. Ending in control letter (A-J): Spain::PATTERN_3

From experience I know that my implementation is correct, I have been able to verify it with hundreds of TINs of different types of legal entities.

I am looking for information on official sites such as pages of the Spanish Government or the BOE (where the laws are published).
I also prefer to have official references.

[drupol]

Thanks, I also wrote an email to DG Taxud for having more official informations too, I'll keep you posted.

[alphp]

This document is interesting, it is on a Spanish Government website but it is prepared from information from a forum or similar:
https://www.mapa.gob.es/app/materialvegetal/docs/CIF.pdf
It is interesting because the code follows the algorithm described on Wikipedia, which I have implemented. Except that it only contemplates two types of CIF that end in a letter, when there are a few more cases.
I keep searching, but I probably won't find an official source, this is Spain and its public administration.

[alphp]

The only official references I have found about the TINs of legal entities are about the format, not about verification:
https://sede.agenciatributaria.gob.es/Sede/todas-gestiones/impuestos-tasas/declaraciones-informativas/modelo-289-decla_____ras-ambito-asistencia-mutua/portales-web-validaciones-tin.html
TIN_-_country_sheet_ES_es.pdf
https://www.oecd.org/tax/automatic-exchange/crs-implementation-and-assistance/tax-identification-numbers/Spain-TIN.pdf
Spain-TIN.pdf

[alphp]

I have found a public administration that describes the validation algorithm for TINs of legal entities.
This is the Junta de Andalucía, the highest public institution of the autonomous community of Andalusia.
The help website for software development for public administration describes the two algorithms for verifying Spanish TINs.
This is the link:
https://www.juntadeandalucia.es/servicios/madeja/sites/default/files/historico/1.4.0/contenido-libro-pautas-196.html#Validacion_de_NIF_con_tipo_distinto_a_DNI

Unfortunately it does not provide information about the regulations where these algorithms are defined. However, we have a description of them from an institutional website.

[drupol]

Please don't use merge but do a simple rebase... it will be easier for me to review.

[alphp]

Something went wrong while trying to rebase.
I have created a new branch and a new PR #41 with the changes applied to the last commit of the master branch.