私達はmodernize packageに夢を見るか feat. go/analysis, go/ast / Go Conference 2025

Go Conference 2025 Day2 での登壇資料です
https://gocon.jp/2025/talks/959035/

1. ࢲୡ͸ modernize package ʹ ເΛݟΔ͔ feat. go/analysis, go/ast Go Conference 2025 (2025/09/28) Kaoru Muta / mentos
2. ࣗݾ঺հ 2 Kaoru Muta ໂా ܆ (ϝϯτε) ੜ·ΕҭͪେࡕͰࠓ΋େࡕʹ͍·͢ 🐯 גࣜձࣾBuySell Technologies ͰόοΫΤϯυ୲౰ ϒϩϯζεϙϯαʔͱͯ͠ڠࢍͯ͠ΔΑʂ ങऔɾࠪఆ ങऔछผʹԠͨ͡࠷దͳγεςϜߏங Visit -๚໰ങऔ- Store -ళฮങऔ- ങऔ ϦϢʔεϓϥοτϑΥʔϜCosmos ࣗࣾ։ൃͷϦϢʔεಛԽۀ຿جװγεςϜͰ͋ΓαʔϏε܈ͷू߹ମ @m_t_tion1
3. ͏Θͬɾɾɾࢲୡͷ Go version ݹ͗͢ɾɾɾʁ 3 ͱࢥͬͨܦݧ͸͋Γ·͔͢ʁ ձ৔ͷօ༷ͥͻڍखͰ✋
4. ͥͻ version Λ͋͛·͠ΐ͏ 4 Go ͸جຊతʹޙํޓ׵ੑ͕ όʔδϣϯؒͰ୲อ͞Ε͍ͯΔ
5. ͏Θͬɾɾɾࢲୡͷ Go ͷه๏ ݹ͗͢ɾɾɾʁ 5 ͱࢥͬͨܦݧ͸͋Γ·͔͢ʁ ձ৔ͷօ༷ͥͻڍखͰ✋
6. ࠷৽ͷه๏Λਵ࣌औΓೖΕΔͱ ॻ͖ํ͕ࢄΒ͹ͬͯ͘Δͷ͕ एׯؾʹͳΔ (࢓ํͳ͍) 6 γϡοͱ౷ҰͰ͖Ε͹ͱաڈʹເݟͨΓ (ࠔͬͯ͸ͳ͍ΜͰ͚͢ͲͶ)
7. ͦΜͳ࣌ʹ modernize package Λ࢖͑͹ ເΛݟΕΔ͔΋͠Εͳ͍ 7 ҆શʹ͔ͭத਎Λཧղ͠ͳ͕Β ࢖͓͏ʂͱ͍͏ൃදͰ͢
8. modernize package ͱ͸ • gopls ʹೖ͍ͬͯΔ (2025/9 ࣌఺Ͱ͸ v0.2.0) • go run ίϚϯυͰ࣮ߦͰ͖Δ ◦ -fix Ͱɺ࠷৽ͷ Go ͰऔΓೖΕΒΕͨه๏Λద༻ͯ͘͠ΕΔ 8
9. modernize package ͱ͸ 9 forvar (Go 1.22 ~) waitgroup (Go 1.25 ~) ଞʹ΋ɺefaceany (interface{} → any) ͳͲɺෳ਺ͷέʔεʹରԠ
10. †ࠇຐज़†Ͱ͸ɾɾɾʁ 10
11. ಺෦࣮૷ݟΔͧʂ 11 ࠓճ͸ forvar ͷ࣮૷Λ Έ͍͖ͯ·͢
12. લఏ஌ࣝ - go/ast 12 Go ιʔείʔυͷந৅ߏจ໦ (AST) Λදݱ͢ΔͨΊͷύοέʔδ #1. Node AST ͷ֤ཁૉ (ex. จɾࣜɾม਺) จͷ AST Node Λ Stmt interface Ͱѻ͏ #2. Token ࣈ۟ͷ࠷খཁૉ (ex. ԋࢉࢠɾϦςϥϧ)
13. લఏ஌ࣝ - go/analysis 13 Go Ͱ੩తղੳΛ࣮૷͢ΔͨΊͷϑϨʔϜϫʔΫ #1. Analyzer ίʔυͷղੳΛߦ͏ղੳثͷ࣮ମ #2. Pass ύοέʔδͷղੳ৘ใΛ٧Ίͨ΋ͷ
14. લఏ஌ࣝ - go/analysis 14 Go Ͱ੩తղੳΛ࣮૷͢ΔͨΊͷϑϨʔϜϫʔΫ #3. Diagnostic Analyzer ͕ग़ྗ͢Δࢦఠࣄ߲ #4. SuggestedFix Diagnostic ʹରͯ͠ͷमਖ਼Ҋ (CLI Ͱ -fix option Ͱमਖ਼Λద༻Ͱ͖Δ)
15. forvar - Analyzer ͷఆٛ 15
16. forvar - Analyzer ͷఆٛ 16 ղੳ͢Δ্Ͱ࣮ߦ͕ඞཁͳ લॲཧͷAnalyzerͷఆٛ
17. forvar - Analyzer ͷఆٛ 17 ࣮ࡍͷղੳॲཧΛهड़
18. 18 ΍͍ͬͯΔ͜ͱ #1. Go version ͷ࠷খཁ݅Λ֬ೝ #2. for range Λ࢖͍ͬͯΔՕॴͷݕग़ #3. ৚݅ʹҰகͨ͠ՕॴΛॻ͖׵͑
19. 19 ΍͍ͬͯΔ͜ͱ #1. Go version ͷ࠷খཁ݅Λ֬ೝ #2. for range Λ࢖͍ͬͯΔՕॴͷݕग़ #3. ৚݅ʹҰகͨ͠ՕॴΛॻ͖׵͑
20. #1. Go version ͷ࠷খཁ݅Λ֬ೝ 20
21. #1. Go version ͷ࠷খཁ݅Λ֬ೝ 21 ࣗಈੜ੒ϑΝΠϧ͔Ͳ͏͔Λݕग़ ΋ͦ͠͏ͩͬͨ৔߹ແࢹ͢Δ
22. #1. Go version ͷ࠷খཁ݅Λ֬ೝ 22 લॲཧͰ࣮ߦͨ͠inspect.Analyzer ͷ ղੳ݁ՌΛड͚औΔ
23. #1. Go version ͷ࠷খཁ݅Λ֬ೝ 23 ࠷খཁ͕݅ Go 1.22 ͷϑΝΠϧΛ Ұͭͣͭ૸͍ࠪͯ͘͠
24. #1. Go version ͷ࠷খཁ݅Λ֬ೝ 24 ର৅ͷϑΝΠϧ಺ʹଘࡏ͢Δ for range จ ͷ stmt ΛҰͭͣͭ૸ࠪ
25. 25 ΍͍ͬͯΔ͜ͱ #1. Go version ͷ࠷খཁ݅Λ֬ೝ #2. for range Λ࢖͍ͬͯΔՕॴͷݕग़ #3. ৚݅ʹҰகͨ͠ՕॴΛॻ͖׵͑
26. #2. for range Λ࢖͍ͬͯΔՕॴͷݕग़ 26
27. ϊʔυ Λ for range จͱͯ͠ղऍ ϧʔϓม਺Λએݴ͍ͯ͠Δ΋ͷ͕ ର৅ (ex. `for k, v := range m`) #2. for range Λ࢖͍ͬͯΔՕॴͷݕग़ 27
28. #2. for range Λ࢖͍ͬͯΔՕॴͷݕग़ 28 ϧʔϓͷதͰɺม਺Λಉ໊Ͱ ࠶એݴ͍ͯ͠Δ͔ͷ൑ఆΛߦ͏ؔ਺ (ex. k := k)
29. #2. for range Λ࢖͍ͬͯΔՕॴͷݕग़ 29 • ࠨ߲ͱӈ߲͕౳͍͠ • ϧʔϓม਺ͱࠨ߲͕౳͍͠ ৔߹Ҏ֎͸আ֎
30. 30 ΍͍ͬͯΔ͜ͱ #1. Go version ͷ࠷খཁ݅Λ֬ೝ #2. for range Λ࢖͍ͬͯΔՕॴͷݕग़ #3. ৚݅ʹҰகͨ͠ՕॴΛॻ͖׵͑
31. #3. ৚݅ʹҰகͨ͠ՕॴΛॻ͖׵͑ 31
32. #3. ৚݅ʹҰகͨ͠ՕॴΛॻ͖׵͑ 32 for range ϧʔϓΛ1ߦͣͭ૸ࠪ ͦͷ͏ͪɺ৚݅ʹҰகͨ͠΋ͷΛ ॻ͖׵͑Δ
33. #3. ৚݅ʹҰகͨ͠ՕॴΛॻ͖׵͑ 33 • ࣜϊʔυʹม׵ • ԋࢉࢠ͕ʮ:=ʯ • ࠨ߲ͱӈ߲͕౳͍͠ • ϧʔϓม਺Λ࠶એݴ͍ͯ͠Δ
34. #3. ৚݅ʹҰகͨ͠ՕॴΛॻ͖׵͑ 34 • Diagnostic ʹղੳ݁ՌΛηοτ • SuggestedFix ʹ͸ɺ for range Ͱม਺࠶એ ݴͷՕॴΛ࡟আ͢Δमਖ਼ҊΛηοτ
35. ࢖͏ʹ͋ͨͬͯͷݸਓͷҙݟ & ཹҙ͢΂͖఺ • modernize ͸Թ౓ײߴ͘ɺ࠷৽ͷมߋʹ௥ैͯ͘͠Ε͍ͯΔ༷ࢠ ◦ waitgroup.Go ͕ Go 1.25 ʹ approve ͞Εͨ͜ͱΛड͚ͯ ଈ࠲ʹରԠ͍ͯ͠Δ: https://github.com/golang/go/issues/73059 • ੜ੒AIʹίʔυΛॻ͔ͤΔ؍఺ ◦ ੲͷόʔδϣϯͰॻ͍ͯ͘Δ৔߹ʹରԠ͕ඞཁ͔΋ ◦ CI Ͱ modernize -test Λ࣮ߦͯ͠ɺࣦഊΛݩʹमਖ਼ͤ͞Δɾɾʁ • େલఏɺ͋͘·Ͱ beta Ͱ͋Γɺissue ΋͕͍͋ͬͯΔ ◦ https://github.com/golang/go/issues/75358 : ࣮ߦ࣌ʹ panic 35
36. ເʹ͏ͭͭΛൈ͔͞ͳ͍ ఔ౓ʹ࢖ͬͯΈΔͷ͕Αͦ͞͏ 36 ਖ਼͍͠มߋ͔͸֤ʑ͕ ݟۃΊ·͠ΐ͏
37. ࢀߟจݙ • https://pkg.go.dev/golang.org/x/tools/gopls/internal/analysis/ modernize • https://pkg.go.dev/golang.org/x/tools/go/analysis • https://pkg.go.dev/golang.org/x/tools/go/ast/inspector • https://zenn.dev/hsaki/books/golang-static-analysis • https://zenn.dev/urakawa_jinsei/articles/3efa94ac6d16e7 37
38. Thank You! 38