CIDER does not support new ClojureScript Node.js REPL

[cap10morgan]

ClojureScript 0.0-2665 has a new Node.js-based REPL that would be great to use with CIDER. Here's a good starting point for the new REPL.

Currently CIDER tries to connect to it, but it clearly isn't compatible.

[cichli]

Hi! CIDER can only interact with REPLs that use the nREPL protocol, which the CLJS REPL does not out-of-the-box. Fortunately you can use piggieback to accomplish this, the current snapshot version of which supports the new node.js REPL.

• Add [com.cemerick/piggieback "0.1.5-SNAPSHOT"] to your project's dependencies.
• Connect to a normal CLJ REPL in your project by opening a Clojure file and using cider-jack-in (or C-c M-j).
• Eval the following code (equivalent to the repl script in David's blog post, but using piggieback):

(require '[cljs.repl.node :as node]
         '[cemerick.piggieback :as piggieback])

(piggieback/cljs-repl :repl-env (node/repl-env)
                      :output-dir "out"
                      :optimizations :none
                      :cache-analysis true
                      :source-map true)

CIDER will now use the running CLJS REPL to power its autocompletion, documentation/source lookup, etc.

@bbatsov once piggieback 0.1.5 is released I'll open a PR to update the documentation accordingly.

[bbatsov]

@cichli I think piggieback 0.1.5 was released about a month ago. :-)

In other exciting news - it seems that after the recent cljs changes we might not need piggieback soon.

[tangrammer]

Hi Folks, I tried your solution with this config (I create a cljs project with https://github.com/swannodette/mies-node-template) and only added piggieback requirements

(defproject hello-world "0.1.0-SNAPSHOT"
  :description "FIXME: write this!"
  :url "http://example.com/FIXME"

  :dependencies [[org.clojure/clojure "1.6.0"]
                 [org.clojure/clojurescript "0.0-2755"]
                 [com.cemerick/piggieback "0.1.5-SNAPSHOT"]]

  :node-dependencies [[source-map-support "0.2.8"]]

  :plugins [[lein-cljsbuild "1.0.4"]
            [lein-npm "0.4.0"]]

  :source-paths ["src" "target/classes"]

  :clean-targets ["out" "out-adv"]
  :repl-options {:nrepl-middleware [cemerick.piggieback/wrap-cljs-repl]}

  :cljsbuild {
    :builds [{:id "dev"
              :source-paths ["src"]
              :compiler {
                :main hello-world.core
                :output-to "out/hello_world.js"
                :output-dir "out"
                :optimizations :none
                :cache-analysis true
                :source-map true}}
             {:id "release"
              :source-paths ["src"]
              :compiler {
                :main hello-world.core
                :output-to "out-adv/hello_world.min.js"
                :output-dir "out-adv"
                :optimizations :advanced
                :pretty-print false}}]})

But I get "No such file or directory"

2. Unhandled java.io.IOException
   Cannot run program "node": error=2, No such file or directory

           ProcessBuilder.java: 1048  java.lang.ProcessBuilder/start
                      node.clj:   88  cljs.repl.node/setup
                      node.clj:  160  cljs.repl.node.NodeEnv/_setup
                      repl.clj:   93  cljs.repl/eval4412/fn/G
                      repl.clj:   93  cljs.repl/eval4412/fn/G
                piggieback.clj:  196  cemerick.piggieback/cljs-repl/fn
                piggieback.clj:  194  cemerick.piggieback/cljs-repl
                   RestFn.java:  805  clojure.lang.RestFn/invoke
                          REPL:    4  user/eval7138
                 Compiler.java: 6703  clojure.lang.Compiler/eval
                 Compiler.java: 6666  clojure.lang.Compiler/eval
                      core.clj: 2927  clojure.core/eval
                      main.clj:  239  clojure.main/repl/read-eval-print/fn
                      main.clj:  239  clojure.main/repl/read-eval-print
                      main.clj:  257  clojure.main/repl/fn
                      main.clj:  257  clojure.main/repl
                   RestFn.java: 1523  clojure.lang.RestFn/invoke
        interruptible_eval.clj:   67  clojure.tools.nrepl.middleware.interruptible-eval/evaluate/fn
                      AFn.java:  152  clojure.lang.AFn/applyToHelper
                      AFn.java:  144  clojure.lang.AFn/applyTo
                      core.clj:  624  clojure.core/apply
                      core.clj: 1862  clojure.core/with-bindings*
                   RestFn.java:  425  clojure.lang.RestFn/invoke
        interruptible_eval.clj:   51  clojure.tools.nrepl.middleware.interruptible-eval/evaluate
        interruptible_eval.clj:  183  clojure.tools.nrepl.middleware.interruptible-eval/interruptible-eval/fn/fn
        interruptible_eval.clj:  152  clojure.tools.nrepl.middleware.interruptible-eval/run-next/fn
                      AFn.java:   22  clojure.lang.AFn/run
       ThreadPoolExecutor.java: 1142  java.util.concurrent.ThreadPoolExecutor/runWorker
       ThreadPoolExecutor.java:  617  java.util.concurrent.ThreadPoolExecutor$Worker/run
                   Thread.java:  745  java.lang.Thread/run

1. Caused by java.io.IOException
   error=2, No such file or directory

              UNIXProcess.java:   -2  java.lang.UNIXProcess/forkAndExec
              UNIXProcess.java:  185  java.lang.UNIXProcess/<init>
              ProcessImpl.java:  134  java.lang.ProcessImpl/start
           ProcessBuilder.java: 1029  java.lang.ProcessBuilder/start
                      node.clj:   88  cljs.repl.node/setup
                      node.clj:  160  cljs.repl.node.NodeEnv/_setup
                      repl.clj:   93  cljs.repl/eval4412/fn/G
                      repl.clj:   93  cljs.repl/eval4412/fn/G
                piggieback.clj:  196  cemerick.piggieback/cljs-repl/fn
                piggieback.clj:  194  cemerick.piggieback/cljs-repl
                   RestFn.java:  805  clojure.lang.RestFn/invoke
                          REPL:    4  user/eval7138

[cichli]

@tangrammer do you have node installed? :-)

[expez]

@cichli this works fine now, right? The repl should be on the nrepl protocol by now.