Org-Babel Javascript error

Question

I am having trouble getting the simplest Javascript source block in org-mode to run.

  #+begin_src js
    console.log("Hello");
  #+end_src

I always get this error:

/tmp/babel-8kqQwQ/js-script-shBzKH:1
require('sys').print(require('sys').inspect(function(){
               ^

TypeError: require(...).print is not a function
    at Object.<anonymous> (/tmp/babel-8kqQwQ/js-script-shBzKH:1:16)
    at Module._compile (internal/modules/cjs/loader.js:1151:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1171:10)
    at Module.load (internal/modules/cjs/loader.js:1000:32)
    at Function.Module._load (internal/modules/cjs/loader.js:899:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
    at internal/main/run_main_module.js:17:47

I am running on Spacemacs and did the configuration as described in the Org Wiki https://orgmode.org/worg/org-contrib/babel/languages/ob-doc-js.html

OS is the latest Manjaro. Emacs 26.3

The funny thing is, I am running my Emacs on my other machine with the exact same config. Same OS, same Emacs, same .spacemacs file. No issues.
I even did a fresh install of Spacemacs with the current config template on both systems. Same result. The desktop works, the notebook doesn't.

I can only imagine that an external JS runner is missing or broken?

I really don't know how to debug this.

Answer 1

Looks like a bug as wasamasa said, but until that gets fixed this works for me:

(setq org-babel-js-function-wrapper
      "console.log(require('util').inspect(function(){\n%s\n}(), { depth: 100 }))")

If you want to print deeper or otherwise modify output, change the options for require('util').inspect(...) in that string, as documented here.

If you want to print a value into org without explicitly calling console.log in your own source block, put a return statement in your source block:

#+BEGIN_SRC js
  return 1 + 1;
#+END_SRC

#+RESULTS:
: 2

Answer 2

Org supports evaluating JavaScript either via Node.js or mozrepl. Your error message suggests you're using Node, but your current version of it doesn't support the sys module. Which is kind of bad, consider reporting an Org bug about that.