Time.zone.parse('dark')/time-zone-parse-dark

Transcript

1. Time.zone .parse(‘dark’) 森塚 真年(@sanfrecce_osaka) 2025/04/30 Kyobashi.rb#6 #kyobashirb
2. 注: 言うほど闇では ないかもしれないです 良いタイトル思いつかなかった
3. 自己紹介 森塚 真年 GitHub: @sanfrecce-osaka Twitter(X) ・Qiita: @sanfrecce_osaka 趣味: コミュニティ・勉強会 Machida.rb Hirakata.rb 株式会社Leaner Technologies Ruby3.4/Rails8.0 Next.js 14.2
4. 本編
5. しばしば書きませんか？ Time.zone.parse('2020-10-10T10:10:10+09:00')
6. ここで問題です
7. 次の場合どうなるでしょう？ 1. 例外(ArgumentError) 2. nil 3. 2020-10-10 10:10:10.000000000 JST +09:00 4. 2025-10-10 10:10:10.000000000 JST +09:00 5. 2025-04-30 00:00:00.000000000 JST +09:00 6. 該当なし # 年の最後が数字じゃなくてアルファベット Time.zone.parse('202O-10-10T10:10:10+09:00')
8. 正解 Time.zone.parse('202O-10-10T10:10:10+09:00') # => 2025-04-30 10:10:10.000000000 JST +09:00
9. why?
10. コードを追ってみました
11. show_source 参考: https://onk.hatenablog.jp/entry/2022/10/10/003542 irb(main):001> $ Time.zone.parse From: /xxx/activesupport-8.0.2/lib /active_support/values/time_zone.rb:453 def parse(str, now = now()) parts_to_time(Date._parse(str, false), now) end
12. Date._parse ドキュメント: 実装: https://docs.ruby-lang.org/ja/3.4/method/Date/s/_parse.html https://github.com/ruby/ruby/blob/v3_4_3/ext/date/date_core.c#L4481-L4498 irb(main):002> Date._parse('2020-10-10T10:10:10+09:00') # => {zone: "+09:00", hour: 10, min: 10, sec: 10, # year: 2020, mon: 10, mday: 10, offset: 32400 } irb(main):003> Date._parse('202O-10-10T10:10:10+09:00') # => {zone: "+09:00", hour: 10, min: 10, sec: 10, # yday: 202, offset: 32400 }
13. ActiveSupport::TimeZone #parts_to_time https://github.com/rails/rails/blob/v8.0.2/activesupport/lib/active_support/values/time_zone.rb#L585-L608 irb(main):004> $ Time.zone.parts_to_time From: /xxx/activesupport-8.0.2/lib /active_support/values/time_zone.rb:585
14. def parts_to_time(parts, now) raise ArgumentError, "invalid date" if parts.nil? return if parts.empty?
15. if parts[:seconds] time = Time.at(parts[:seconds]) else time = Time.new( parts.fetch(:year, now.year), parts.fetch(:mon, now.month), parts.fetch(:mday, parts[:year] || parts[:mon] ? 1 : now.day), parts.fetch(:hour, 0), parts.fetch(:min, 0), parts.fetch(:sec, 0) + parts.fetch(:sec_fraction, 0), parts.fetch(:offset, 0) ) end
16. if parts[:offset] || parts[:seconds] TimeWithZone.new(time.utc, self) else TimeWithZone.new(nil, self, time) end end
17. その他の挙動 irb(main):005> Time.zone.parse('') # => nil irb(main):006> Time.zone.parse(nil) # => no implicit conversion of nil into String (TypeError) irb(main):007> Time.zone.parse('2020') # => argument out of range (ArgumentError) irb(main):008> Time.zone.parse('202O') # => 2025-04-30 00:00:00.000000000 JST +09:00 irb(main):009> Time.zone.parse('ほげ') # => nil irb(main):010> Time.zone.parse('ほげ-10') # => 2025-04-10 00:00:00.000000000 JST +09:00
18. 難しい／(^o^) ＼
19. invalid な文字列は弾きたい
20. が rails のバリデータ ない(´ ・ω ・｀) gem なさそう(´ ・ω ・｀)
21. そこで
22. ActiveSupport::TimeZone #strptime irb(main):011> $ Time.zone.strptime From: /xxx/activesupport-8.0.2/lib /active_support/values/time_zone.rb:507 def strptime(str, format, now = now()) parts_to_time(DateTime._strptime(str, format), now) end
23. DateTime._strptime ドキュメント: 実装: https://docs.ruby-lang.org/ja/3.4/method/DateTime/s/_strptime.html https://github.com/ruby/ruby/blob/v3_4_3/ext/date/date_core.c#L4327-L4374 irb(main):012* DateTime._strptime( irb(main):013* '2020-10-10T10:10:10+09:00', irb(main):014> '%Y-%m-%dT%H:%M:%S') # => {year: 2020, mon: 10, mday: 10, # hour: 10, min: 10, sec: 10, # zone: "+09:00", offset: 32400 } irb(main):015* DateTime._strptime( irb(main):016* '202O-10-10T10:10:10+09:00', irb(main):017* '%Y-%m-%dT%H:%M:%S') # => nil
24. def parts_to_time(parts, now) raise ArgumentError, "invalid date" if parts.nil? return if parts.empty?
25. irb(main):018* Time.zone.strptime( irb(main):019* '2020-10-10T10:10:10+09:00', irb(main):020> '%Y-%m-%dT%H:%M:%S') # => 2020-10-10 10:10:10.000000000 JST +09:00 irb(main):021* Time.zone.strptime( irb(main):022* '202O-10-10T10:10:10+09:00', irb(main):023> '%Y-%m-%dT%H:%M:%S') # => invalid date (ArgumentError)
26. グッ(๑•̀ ㅂ•́)و✧
27. 皆さん どうしてますか？
28. もっといい方法あったら おしえてほすい (´ω ｀)
29. ご清聴 ありがとうございました。