Why validation is case insensitive?

[alexkuc]

As per title, I don't understand why validation of letter case is insensitive since it forms part of the standard?

Official definition of ISO-3166 standard does not indicate the case of letters, however, when using ISO search, the alpha-2 or alpha-3 standard always uses uppercase. Also, the underlying dependency arslanimamutdinov/iso-standard-3166 uses uppercase for alpha-2 or alpha-3.

[arslanim]

First of all, hello. Thank you for your question. As you mentioned in your issue, official definition of ISO-3166 does not indicate the case of letters. So I believe that alpha-2 and alpha-3 codes in both uppercase and lowercase are valid from the point of view of the standard. If you have links to official docs that disprove this, I'd be happy to look at them and make corrections to the code.

As for the repository https://github.com/arslanim/iso-standard-3166, its implementation was obtained by code that automatically parsed pages with standards and generated code in accordance with the results of this parsing. Accordingly, the alpha-2 and alpha-3 codes there were in uppercase.

[alexkuc]

Hello @arslanim

If you have links to official docs that disprove this

Unfortunately, the official documentation is behind a paywall. However, stefangabos/world_countries#50 indicates that letters should be in the uppercase.