add new main opt for starting simple web server

Author: swannodette

src/main/clojure/cljs/cli.clj

@@ -404,6 +404,19 @@ present"
   ((::compile (repl/-repl-options (repl-env)) default-compile)
     repl-env (merge cfg {:args args :ns ns})))
 
+(defn- serve-opt
+  [_ [_ address-port & args] {:keys [options] :as cfg}]
+  (let [[host port] (if address-port
+                      (string/split address-port #":")
+                      ["localhost" 9000])]
+    (require 'cljs.repl.browser)
+    ((ns-resolve 'cljs.repl.browser 'serve)
+      {:host host
+       :port (if port
+               (cond-> port (string? port) Integer/parseInt)
+               9000)
+       :output-dir (:output-dir options "out")})))
+
 (defn get-options [commands k]
   (if (= :all k)
     (into (get-options commands :main) (get-options commands :init))
@@ -493,6 +506,9 @@ present"
                                 :arg "ns"
                                 :doc (str "Compile a namespace. If -r / --repl present after "
                                        "namespace will launch a REPL after the compile completes")}
+      ["-s" "--serve"]         {:fn serve-opt
+                                :arg "host:port"
+                                :doc (str "Start a simple web server to serve the current directory")}
       [nil]                    {:fn null-opt}
       ["-h" "--help" "-?"]     {:fn help-opt
                                 :doc "Print this help message and exit"}}}))

src/main/clojure/cljs/repl/browser.clj

@@ -275,6 +275,15 @@
   [repl-env provides url]
   (browser-eval (slurp url)))
 
+(defn serve [{:keys [host port output-dir] :as opts}]
+  (println "Serving HTTP on" host "port" port)
+  (binding [ordering (agent {:expecting nil :fns {}})
+            es (Executors/newFixedThreadPool 16)
+            server/state (atom {:socket nil :connection nil :promised-conn nil})]
+    (server/start
+      (merge opts
+        {:static-dir (cond-> ["." "out/"] output-dir (conj output-dir))}))))
+
 ;; =============================================================================
 ;; BrowserEnv
 
@@ -360,12 +369,11 @@
      :launch-browser true
      :working-dir (->> [".repl" (util/clojurescript-version)]
                        (remove empty?) (string/join "-"))
-     :serve-static true
      :static-dir (cond-> ["." "out/"] output-dir (conj output-dir))
      :preloaded-libs []
      :src "src/"
      :browser-state (atom {:return-value-fn nil
-                          :client-js nil})
+                           :client-js nil})
      :ordering (agent {:expecting nil :fns {}})
      :es (Executors/newFixedThreadPool 16)
      :server-state
@@ -386,8 +394,6 @@
   working-dir:    The directory where the compiled REPL client JavaScript will
                   be stored. Defaults to \".repl\" with a ClojureScript version
                   suffix, eg. \".repl-0.0-2138\".
-  serve-static:   Should the REPL server attempt to serve static content?
-                  Defaults to true.
   static-dir:     List of directories to search for static content. Defaults to
                   [\".\" \"out/\"].
   src:            The source directory containing user-defined cljs files. Used to