Linter: one resource per ns

[vemv]

There should be exactly one JVM resource backing a given clj/s ns. Else its source would be ambiguous, leading to hard-to-debug errors. Normally these are caused by 'dirty' libraries or an incorrect project.clj configuration.

I developed the following snippet which could serve as a base for a linter against that:

(defn resources
  ([n]
   (resources n (.getContextClassLoader (Thread/currentThread))))
  
  ([n ^ClassLoader loader]
   (.getResources loader n)))

(->> "clojure/core/specs/alpha.clj"
     resources
     enumeration-seq
     (map str)
     (clojure.pprint/pprint))

;; the above results in:
'("jar:file:/Users/vemv/.m2/repository/clojure-future-spec/clojure-future-spec/1.9.0-beta4/clojure-future-spec-1.9.0-beta4.jar!/clojure/core/specs/alpha.clj"
  "jar:file:/Users/vemv/.m2/repository/org/clojure/core.specs.alpha/0.2.44/core.specs.alpha-0.2.44.jar!/clojure/core/specs/alpha.clj")