Clojure Linters

Utilise linters for clean Clojure code (*> ᴗ •*)ゞ

Transcript

1. Clojure Linters
2. Self-introduction /laʒenɔʁɛ̃k/ カマイルカ lagénorhynque (defprofile lagénorhynque :name "Kent OHASHI" :languages [Clojure Haskell Python Scala English français Deutsch русский] :interests [programming language-learning mathematics] :contributing [github.com/japan-clojurians/clojure-site-ja])
3. 「Clojureをプロダクトに導⼊した話」
4. 1. cljfmt: formatter 2. eastwood: linter 3. kibit: idiom checker 4. Example Usage 5. Other Tools
5. formatter cljfmt
6. What's the problem? (when something (something-else) )
7. $ lein cljfmt check (when something - (something-else) -) + (something-else))
8. What's the problem? (when something something-else)
9. $ lein cljfmt check (when something - something-else) + something-else)
10. What's the problem? (filter even? (range 1 10))
11. $ lein cljfmt check (filter even? - (range 1 10)) + (range 1 10))
12. What's the problem? (if something ala bala)
13. $ lein cljfmt check (if something - ala - bala) + ala + bala)
14. What's the problem? (or ala bala portokala)
15. $ lein cljfmt check (or - ala - bala - portokala) + ala + bala + portokala)
16. linter eastwood
17. What's the problem? (ns linting-example.eastwood-target (:use [clojure.string]))
18. $ lein eastwood src/linting_example/eastwood_target.clj:2:10: unlimited-use: Unl imited use of ([clojure.string]) in linting-example.eastwood-tar get
19. What's the problem? (if-let [x []] (conj x 42) :falsy)
20. $ lein eastwood src/linting_example/eastwood_target.clj:4:1: constant-test: Test expression is always logical true or always logical false: [] in form (if temp__5455__auto__ (clojure.core/let [x temp__5455__aut o__] (conj x 42)) :falsy)
21. What's the problem? (defn f [x] (def y (* x x)) (+ y 2))
22. $ lein eastwood src/linting_example/eastwood_target.clj:9:8: def-in-def: There i s a def of y nested inside def f
23. What's the problem? (defn g [x] "blah blah blah." (* x x))
24. $ lein eastwood src/linting_example/eastwood_target.clj:12:7: misplaced-docstrin gs: Possibly misplaced docstring, g src/linting_example/eastwood_target.clj:12:1: unused-ret-vals: C onstant value is discarded: "blah blah blah."
25. What's the problem? (defn h [str] (str "Hello, " str "!"))
26. $ lein eastwood src/linting_example/eastwood_target.clj:17:3: local-shadows-var: local: str invoked as function shadows var: #'clojure.core/str
27. idiom checker kibit
28. What's the problem? (defn add-one [x] (+ x 1))
29. $ lein kibit At src/linting_example/kibit_target.clj:4: Consider using: (inc x) instead of: (+ x 1)
30. What's the problem? (defn check-if-zero? [x] (== x 0))
31. $ lein kibit At src/linting_example/kibit_target.clj:7: Consider using: (zero? x) instead of: (== x 0)
32. What's the problem? (defn zip-with-* [xs ys] (map #(* %1 %2) xs ys))
33. $ lein kibit At src/linting_example/kibit_target.clj:null: Consider using: * instead of: #(* %1 %2)
34. What's the problem? (defn coll->vec [coll] (into [] coll))
35. $ lein kibit At src/linting_example/kibit_target.clj:13: Consider using: (vec coll) instead of: (into [] coll)
36. What's the problem? (defn flat-map [f coll] (apply concat (map f coll)))
37. $ lein kibit At src/linting_example/kibit_target.clj:16: Consider using: (mapcat f coll) instead of: (apply concat (map f coll))
38. Example Usage
39. e.g. ↓↓↓ lagenorhynque/situated-program- challenge/rest-server/project.clj :plugins [[jonase/eastwood "0.2.5"] [lein-cljfmt "0.5.7"] [lein-kibit "0.1.6"]] :aliases {"lint" ^{:doc "Execute cljfmt check, eastwood and kibit."} ["do" ["cljfmt" "check"] ["eastwood" "{:source-paths [\"src\"]}"] ["kibit"]]} lein cljfmt check && lein eastwood <opts> && lein kibit = lein do cljfmt check, eastwood <opts>, kibit = lein lint # alias as `lint`
40. $ lein lint All source files formatted correctly == Eastwood 0.2.5 Clojure 1.9.0 JVM 9.0.1 Directories scanned for source files: src test == Linting rest-server.util == == Linting rest-server.boundary.db.core == == Linting rest-server.boundary.db.group == ... == Linting rest-server.handler.venue-test == == Linting rest-server.handler.meetup-test == == Linting rest-server.handler.member-test == == Warnings: 0 (not including reflection warnings) Exceptions thrown: 0
41. Other Tools
42. dependency lein deps :tree lein-ancient
43. namespace slamhound
44. dead code Yagni
45. vulnerability lein-nvd
46. test coverage cloverage
47. misc. lein-bikeshed
48. Utilise linters for clean Clojure code!
49. Further Reading Clojure Code Quality Tools My Clojure Toolchain: Leiningen Automating Style In Clojure The state of code quality tools in Clojure clojure-style-guide