[Validator] IBAN Check digits should always between 2 and 98

[karstennilsen]

Q	A
Branch?	5.4
Bug fix?	yes/no
New feature?	no
Deprecations?	no
Issues	No existing
License	MIT

A ECBS document (https://www.ecbs.org/Download/EBS204_V3.PDF) replicates part of the ISO/IEC 7064:2003 standard as a method for generating check digits in the range 02 to 98.

Besides this I have a production database of 160K valid IBANs. All of them have a check digit between 02 and 98.

Example of invalid IBANs, which before were valid, are NL01INGB0001393698 and NL01RABO0331811235. You can check them at iban.com to verify they are indeed invalid.

[carsonbot]

Hey!

I see that this is your first PR. That is great! Welcome!

Symfony has a contribution guide which I suggest you to read.

In short:

• Always add tests
• Keep backward compatibility (see https://symfony.com/bc).
• Bug fixes must be submitted against the lowest maintained branch where they apply (see https://symfony.com/releases)
• Features and deprecations must be submitted against the 7.1 branch.

Review the GitHub status checks of your pull request and try to solve the reported issues. If some tests are failing, try to see if they are failing because of this change.

When two Symfony core team members approve this change, it will be merged and you will become an official Symfony contributor!
If this PR is merged in a lower version branch, it will be merged up to all maintained branches within a few days.

I am going to sit back now and wait for the reviews.

Cheers!

Carsonbot

[karstennilsen]

7.2 & 8.0 integration & 8.2 unit test failures seem to be non related to changes in this PR

[nicolas-grekas]

Thank you @karstennilsen.