"There are too many JS runtimes, don't know which to eval in."

[lilactown]

Currently building for Node.js. If I kill the built Node.js app, start it, and attempt to evaluate something via nREPL, I get the message: There are too many JS runtimes, don't know which to eval in.

Steps to reproduce:

1. Create a build that targets :nodejs and starts an nREPL server
2. In one terminal, start the build: shadow-cljs watch app
3. In another terminal, start the Node.js server: node target/out/app.js
4. Connect to the nREPL connection remotely (I'm using CIDER)
   4a. Start the CLJS REPL: (shadow.cljs.devtools.api/nrepl-select :app)
5. Kill the app using ctrl-c and start it again: node target/out/app.js
6. Evaluate a form at the remote REPL: (+ 1 1)

Expected result: REPL prints the answer 1
Actual resuult: REPL prints the message There are too many JS runtimes, don't know which to eval in.

[thheller]

Which version are you on? There was a bug related to this a while ago (2.0.50ish I think) but it seems to work now?

(shadow.cljs.devtools.api/nrepl-select :script)
To quit, type: :cljs/quit
=> [:selected :script]
(+ 1 2)
There is no connected JS runtime.
;; now starting node
(+ 1 2)
=> 3
;; now killing node by ctrl+c
(+ 1 2)
There is no connected JS runtime.
;; no starting node again
(+ 1 2)
=> 3

[bolasblack]

Hi @thheller , I encountered an issue, perhaps also have some relationship with this

The shadow-cljs version: 2.1.23

I am following the guide https://github.com/thheller/shadow-cljs/wiki/Cider

And this is my shadow-cljs.edn:

{:dependencies [[org.clojure/core.async "0.4.474"]
                [cider/cider-nrepl "0.17.0-SNAPSHOT"]]
 :source-paths ["src"]
 :cache-root ".shadow-cljs"
 :builds {:main {:target :npm-module
                 :output-dir "lib"
                 :compiler-options {:source-map true}}}}

user> (shadow.cljs.devtools.api/nrepl-select :main)
To quit, type: :cljs/quit
[:selected :main]
user> (js/console.log "hello")
There is no connected JS runtime.
user> (js/console.log "hello")
There is no connected JS runtime.
user> :cljs/quit
:cljs/quit
user> (shadow.cljs.devtools.api/nrepl-select :main)
To quit, type: :cljs/quit
[:selected :main]
user> (js/console.log "hello")
There is no connected JS runtime.
user> (println "hello")
There is no connected JS runtime.
user> 

[thheller]

REPL for a :npm-module is kind of tricky since its meant to be processed by other tools which would most likely break the REPL entirely.

There is no connected JS runtime. means that no node process is running that has loaded the necessary code and connected to the websocket.

You can run shadow-cljs node-repl standalone and then (shadow.cljs.devtools.api/nrepl-select :node-repl) remotely to get a running node process that you can use.

[bolasblack]

@thheller Cool!

I found (println "hello") will print hello in the screen I executed shadow-cljs node-repl, Is it possible to print the message in cider?

[thheller]

Not currently. Please open a separate ticket for that.

[bolasblack]

Sorry both theller and Lokeh 😂

[lilactown]

I had an out of date version of shadow-cljs. Closing.