perf: replaces list of postcodes in ja/address.yml with a 7-digit format - #3201
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…ormat Replaces the full list of japanese postcodes in favor of a simple 7-digit format: "###-####". The reason is for performance, as generating a postcode in this locale is too expensive. Japanese postal codes were changed from a simple pattern to a list of real postal codes, introduced in #2297. The problem is that when running Faker on `locale = 'ja'`, about 60% of the time to load and call `Faker::Address.postalcode` is spent reading and parsing the [ja/address.yml](https://github.com/faker-ruby/faker/blob/main/lib/locales/ja/address.yml) file, which has 2.2mb. Benchmark: ``` Postcode - Smaller Address File: 1.2 i/s Postcode: 0.7 i/s - 1.65x slower 1.34 s/i vs 811.55 ms/i ``` This has the potential to improve the performance of generating postcodes in japanese by 65%.
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test/test_ja_locale.rb
| assert_kind_of String, Faker::Subscription.status | ||
| assert_not_english(Faker::Subscription.status) | ||
| assert_kind_of String, Faker::Subscription.payment_method | ||
| assert Array.new(10) { Faker::Subscription.payment_method }.any? { |word| !word.match?(/[a-zA-Z]/) } |
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this test would randomly generate words that often wouldn't match the filter.
The weird thing is that it should have been happening on main too.
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January 31, 2026 21:37
stefannibrasil
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We don't need to generate every single possible post code out there since we are not Wikipedia 😅 We just need to generate a few samples. It's good to have this done, thanks!
🐡 🅾️
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(fixes #3200)
This PR replaces the full list of postcodes with a 7-digit format for ja/address.yml.
The reason is for performance, as generating a postcode in this locale
is too expensive.
Japanese postal codes were changed from a simple pattern to a list of real postal codes, introduced in #2297.
The problem is that when running Faker on locale = 'ja', about 60% of the time to load and call Faker::Address.postalcode is spent reading and parsing the ja/address.yml file, which has 2.2mb.
Benchmark:
This has the potential to improve the performance of generating
postcodes in japanese by 65%, as well as loading in general.
Gem size will also decrease by 200kb. 🎉
1.6M -> 1.4M