fix cljs.util/debug-prn so it works like println. update compiler

activity logging.

when :watch supplied to cljs.repl/repl bind *err* to the log writer
as well.

sleep 50ms before starting the REPL look to allow futures to flush.

don't start printing until we enter the REPL loop block

Author: swannodette

src/clj/cljs/analyzer.clj

@@ -2057,7 +2057,7 @@ argument, which the reader will use in any emitted errors."
                          *cljs-file* path
                          reader/*alias-map* (or reader/*alias-map* {})]
                  (when (or *verbose* (:verbose opts))
-                   (util/debug-prn "Analyzing " res))
+                   (util/debug-prn "Analyzing" (str res)))
                  (let [env (assoc (empty-env) :build-options opts)
                        ns (loop [ns nil forms (seq (forms-seq res))]
                             (if forms
@@ -2079,7 +2079,7 @@ argument, which the reader will use in any emitted errors."
                           :analyze-deps true
                           :load-macros true}))]
                  (when (or *verbose* (:verbose opts))
-                   (util/debug-prn "Reading analysis cache for " res))
+                   (util/debug-prn "Reading analysis cache for" (str res)))
                  (swap! env/*compiler*
                    (fn [cenv]
                      (let [cached-ns (edn/read-string (slurp cache))]

src/clj/cljs/compiler.clj

@@ -978,15 +978,15 @@
      (with-core-cljs opts
        (fn []
          (when (or ana/*verbose* (:verbose opts))
-           (util/debug-prn "Compiling " src))
+           (util/debug-prn "Compiling" (str src)))
          (if-let [cached (and (= (:optimizations opts) :none)
                               (= (:ns (ana/parse-ns src)) 'cljs.core)
                               (io/resource "cljs/core.aot.js"))]
             ;; no need to bother with analysis cache reading, handled by
             ;; with-core-cljs
             (do
               (when (or ana/*verbose* (:verbose opts))
-                (util/debug-prn "Using cached cljs.core " src))
+                (util/debug-prn "Using cached cljs.core" (str src)))
               (spit dest (slurp cached))
               (when (true? (:source-map opts))
                 (spit (io/file (str dest ".map"))

src/clj/cljs/repl.clj

@@ -654,7 +654,6 @@
                   print-no-newline print
                   source-map-inline true}
              :as opts}]
-  (print "To quit, type:" :cljs/quit)
   (let [{:keys [analyze-path repl-verbose warn-on-undeclared special-fns static-fns] :as opts
          :or   {warn-on-undeclared true}}
         (merge
@@ -733,18 +732,24 @@
                  (future
                    (let [log-file (io/file (util/output-directory opts) "watch.log")]
                      (print "Watch compilation log available at:" (str log-file))
+                     (flush)
                      (try
-                       (binding [*out* (FileWriter. log-file)]
-                         (cljsc/watch src (dissoc opts :watch)))
+                       (let [log-out (FileWriter. log-file)]
+                         (binding [*err* log-out
+                                   *out* log-out]
+                           (cljsc/watch src (dissoc opts :watch))))
                        (catch Throwable e
                          (caught e repl-env opts))))))
+               ;; let any setup async messages flush
+               (Thread/sleep 50)
                (binding [*in* (if (true? (:source-map-inline opts))
                                 *in*
                                 (reader))]
                  (try
                    (init)
                    (catch Throwable e
                      (caught e repl-env opts)))
+                 (print "To quit, type:" :cljs/quit)
                  (prompt)
                  (flush)
                  (loop []

src/clj/cljs/util.clj

@@ -128,7 +128,8 @@
 
 (defn debug-prn
   [& args]
-  (.println System/err (apply str args)))
+  (binding [*out* *err*]
+    (apply println args)))
 
 (defmacro measure
   "Like cljs.core/time but toggleable and takes a message string."
@@ -138,6 +139,6 @@
     `(if ~enable
        (let [start# (. System (nanoTime))
              ret# ~expr]
-         (debug-prn (str ~msg ", elapsed time: " (/ (double (- (. System (nanoTime)) start#)) 1000000.0) " msecs"))
+         (debug-prn ~msg ", elapsed time:" (/ (double (- (. System (nanoTime)) start#)) 1000000.0) "msecs")
          ret#)
        ~expr)))