fix(isIBAN): adjusting Ireland and Palestine IBAN regex

[Tarasz57]

Changes:

Palestine and Ireland IBAN's should consist of countryCode followed by 2 numbers and then 4 [A-Z] symbols, not [A-Z0-9]. This PR adjusts these 2 regexes to follow the required standard.

Sources:

According to Swift documentation, specifically this file here

Checklist

• PR contains only changes related; no stray files, etc.
• README updated (where applicable)
• Tests written (where applicable)
• References provided in PR (where applicable)

[WikiRik]

Thanks for this PR. I was able to verify that your changes seem correct. Can you add some test cases so we don't accidentally change it back?

[Tarasz57]

Of course. I've updated the tests to include both (previously) invalid and now correct IBAN's for both of these countries.

[pano9000]

Kindly correct me, but If I understand this correctly, the Palestine RegExp would be wrong here (the last part):

On page 6 of the supplied PDF we can see the convention:

The supplied PDF says the IBAN structure is PS2!n4!a21!c
The regex here shows /^(PS[0-9]{2})[A-Z]{4}\d{21}$/

So I would argue, that the \d{21} part should actually be [a-zA-Z0-9] or [A-Z0-9] (since we don't care about case, I think).

what do you think?

[Tarasz57]

Good catch. I was focused on the first part of the regex since it was the one that gave me trouble 😄.

As for the [a-zA-Z0-9] or [A-Z0-9] part, I've adjusted regex to include only capital letters, since from what I was able to gather IBAN should be case-insensitive and we're already converting everything to uppercase. I've added a test case that includes a letter as well.