feat(locale): add Welsh (cy) postcode definitions

[IestynGage]

Based on the en_GB postcode definitions with a prefix as recommened by @matthewmayer in #3850 (comment)

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[IestynGage]

The en_GB is just export default ['??# #??', '??## #??']; I suppose you can also add a similiar prefix to en_GB as well. But the postcodes for England, NI, Scotland, Wales, crown dependecies and other special postcodes.

[ST-DDT]

See also #2390

• Invalid zip/postal codes when using locale en_GB #2390

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.91%. Comparing base (e72fd7c) to head (c5759f0).

Additional details and impacted files

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##             next    #3851   +/-   ##
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  Coverage   98.91%   98.91%           
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  Files         905      905           
  Lines        3146     3146           
  Branches      581      581           
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  Hits         3112     3112           
  Misses         30       30           
  Partials        4        4           

Files with missing lines	Coverage Δ
src/locales/cy/location/index.ts	100.00% <ø> (ø)

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[ST-DDT]

Please make sure to test your changes and verify that they return the expected results ⚠️

fakerCY.location.zipCode() // "{{location.postcode_prefix}}76 2MM"

Currently, the zipcode implementation does not support fake patterns (for default patterns).

This is planned for #3233 / #3176

Until then, you have to cross-product them yourself.

[IestynGage]

Please make sure to test your changes and verify that they return the expected results ⚠️

fakerCY.location.zipCode() // "{{location.postcode_prefix}}76 2MM"

Currently, the zipcode implementation does not support fake patterns (for default patterns).

This is planned for #3233 / #3176

Until then, you have to cross-product them yourself.

Oof that's embarrising 🤦 Just a heads up it will be away for a while before I can come back to this :)

@ST-DDT what do you mean by 'cross-product this myself?' Is it that:

• Or do you mean I have to do it by "hand", as in change the content to 'CF# #??', 'CF## #??', etc and remove postcode_prefix?
• update /src/definitions/location.ts?

I pushed a WIP commit of doing the latter, it seems to work. WIP as I would like to update some tests check that the other locales work as well and add documentation.

Also whats the easiest way to run faker locally? via testing or starting pnpm run docs:dev and then using the browser console?

[matthewmayer]

Yes, do it by hand like

['CF# #??', 'CF## #??', 'CH# #??', 'CH## #??'...]

[matthewmayer]

In the long run we would like to move to fake patterns and drop use of replaceSymbols completely, but that will potentially be a breaking change and impacts many locales, so the "by hand" trick is the easiest for now.

[ST-DDT]

Also whats the easiest way to run faker locally? via testing or starting pnpm run docs:dev and then using the browser console?

There are 4 ways. In descending order of my personal preference.

• pnpm tsx my-test.ts (easy to repeat and debug, looking into complex values may require JSON.stringify, no need to switch windows)
• pnpm run docs:dev and then via browser console (easy to look into array/complex values , you may need to run it/generate:apidocs repeatedly)
• clone and use the playground or create your own (you may need to build/install repeatedly)
• write a (temporary) test, (vitest may add noise to your logs or run more tests than you intended)

@faker-js/members Should we document that somewhere or prepare a commamd for that like pnpm run testxecute/texecute? Currently only docs:dev ist documented.

[Shinigami92]

IMO this is a really niche case. However you could store scripts in _local folder, because this folder will be ignored by the clean script.

faker/package.json

Line 6 in 8b4e2b1

"clean": "git clean -fdx --exclude _local",

[matthewmayer]

Also whats the easiest way to run faker locally? via testing or starting pnpm run docs:dev and then using the browser console?

There are 4 ways. In descending order of my personal preference.

• pnpm tsx my-test.ts (easy to repeat and debug, looking into complex values may require JSON.stringify, no need to switch windows)

• pnpm run docs:dev and then via browser console (easy to look into array/complex values , you may need to run it/generate:apidocs repeatedly)

• clone and use the playground or create your own (you may need to build/install repeatedly)

• write a (temporary) test, (vitest may add noise to your logs or run more tests than you intended)

@faker-js/members Should we document that somewhere or prepare a commamd for that like pnpm run testxecute/texecute? Currently only docs:dev ist documented.

Personally I do

pnpm run build
node

Now you are in node REPL so can do like:

const {fakerCY}=require(".")
fakerCY.location.zipCode()

[ST-DDT]

I created a separate issue to discuss dev verification tooling and documentation:

• Add and document verification tooling for contributors #3854

[ST-DDT]

Just a heads up it will be away for a while before I can come back to this :)

Thanks for the heads up.

@ST-DDT what do you mean by 'cross-product this myself?' Is it that:

* Or do you mean I have to do it by "hand", as in change the content to `'CF# #??', 'CF## #??',` etc and remove `postcode_prefix`?

* update `/src/definitions/location.ts`?

I pushed a WIP commit of doing the latter, it seems to work. WIP as I would like to update some tests check that the other locales work as well and add documentation.

Sorry, for not being more clear.

I didn't mean add fake support.
I meant:

const suffixes = ['`## ##?', ...]
const prefixes = ['CY', ...]

export prefixes.flatMap(prefix => suffixes.map(suffix => prefix+suffix))

Either like this or only the result of it.