UK Postcode. Better / more legiible validations

[luke-hill]

Describe the bug

UK Postcode regex isn't strictly speaking true. I am posting this to see if there is appetite / willingness to accept PRs that split out some of the complex regex

To Reproduce

The Generator produced the following invalid postcode. "Y0P 4AX"

Expected behavior

There is a good amount of validation. I would also prefer it if we went down the phone number route of wildcard / less variable stuff. As it's then more legible

Additional context

There are six authorized formats (A=Alpha, N=Numeric): Taken from Market Research and UK Gov

AN NAA (e.g., M1 1AA)
ANN NAA (e.g., M60 1NW)
AAN NAA (e.g., CR2 6XH)
AANN NAA (e.g., DN55 1PT)
ANA NAA (e.g., W1A 1HQ)
AANA NAA (e.g., EC1A 1BB)

However, these can further be granularised.

[stefannibrasil]

To clarify: do you mean the format is wrong or that it's invalid?

If it's the latter, then it's fine. We do not aim to generate valid results.

[luke-hill]

Sometimes Faker can generate invalid postcodes.

I raised a similar issue a while ago on Phone Numbers. Which was met with the same response. I guess from my POV Postcodes are a lot easier to handle. So I'd prefer to either suggest/work on something that splits up a complex regex into "simpler" regexes. Then from there we can maybe go ahead and extract things out further.

It should be viable / probable to produce valid postcodes for the UK because the rules are quite well understood

The reason it's wrong, is because they are invalid. i.e. the rule is wrong. So we should improve the rule - I propose doing this in a series of small PR's to aid reviews and be viable in the short term for contributing