CLJS-2706: Better error messages when missing namespaces contain dashes

Author: kommen

src/main/clojure/cljs/analyzer.cljc

@@ -309,7 +309,9 @@
   (str "No such namespace: " ns-sym
        ", could not locate " (ns->relpath ns-sym :cljs)
        ", " (ns->relpath ns-sym :cljc)
-       ", or JavaScript source providing \"" js-provide "\""))
+       ", or JavaScript source providing \"" js-provide "\""
+    (when (string/includes? (ns->relpath ns-sym) "_")
+      " (Please check that namespaces with dashes use underscores in the ClojureScript file name)")))
 
 (defmethod error-message :undeclared-macros-ns
   [warning-type {:keys [ns-sym js-provide] :as info}]

src/main/clojure/cljs/cli.clj

@@ -373,7 +373,9 @@ present"
                   (when-not src
                     (throw
                       (ex-info
-                        (str "Namespace " main " does not exist")
+                        (str "Namespace " main " does not exist."
+                             (when (string/includes? main "-")
+                               " Please check that namespaces with dashes use underscores in the ClojureScript file name."))
                         {:cljs.main/error :invalid-arg})))
                   (repl/load-stream renv (util/get-name src) src)
                   (repl/evaluate-form renv (ana-api/empty-env) "<cljs repl>"

src/main/clojure/cljs/closure.clj

@@ -805,7 +805,9 @@
                  {:relative-path relpath :uri js-res :ext :js}
                  (throw
                    (IllegalArgumentException.
-                     (str "Namespace " ns " does not exist"))))))))))))
+                     (str "Namespace " ns " does not exist."
+                          (when (string/includes? ns "-")
+                            " Please check that namespaces with dashes use underscores in the ClojureScript file name.")))))))))))))
 
 (defn cljs-dependencies
   "Given a list of all required namespaces, return a list of