Arguments are passed incorrectly when using coffee script #49

szimek opened this Issue Mar 8, 2012 · 8 comments

4 participants



there's the following code in supervisor.js#155:

var spawnme = args ? [prog].concat(args) : [prog];

The issue with it is that coffee script expects options first and then script name:

$ coffee --help
Usage: coffee [options] path/to/

while the code above provides script name first (prog) and then options (args).

Changing the line above to:

var spawnme = args ? args.concat[prog] : [prog];

solves the issue and allows to run node js with debugger enabled like this:

supervisor -- --nodejs --debug

If the order in which script name and arguments should be passed depends on executable, maybe it would be possible to add an option for that (e.g. --options-first), which for coffee would be set by default.

I can write a patch for that if anybody else thinks it's a good idea :)


Hmm, if I understand correctly it's a question of setting the arguments against coffee or node, as opposed to setting them against your own application: node --node-opt app.js vs node app.js --my-opt. I think we should support both, ideally at the same time (a flaw with the --options-first style.

Right now, it's possible to do this like so:

supervisor -x 'coffee' -- --nodejs --debug

Or, it would be possible except for a bug that's inserting a comma for some reason.

I realize this is somewhat awkward syntax. I'm open to suggestions for better ways to do it.


Thanks for the tip! Despite printing out

Starting child process with 'coffee --debug, --nodejs'

it somehow works :) However, I'm using foreman to run the app and it doesn't like this syntax, because it fails with:

web.1     | DEBUG: Starting child process with ''coffee' --debug, --nodejs'
web.1     | DEBUG: execvp(): No such file or directory

Anyway, I think you're right about node options vs application options.

I'm not sure about the comma bug you mentioned, but I guess that it's just displayed incorrectly - in supervisor.js#152 there's the following line:

util.debug("Starting child process with '" + exec + " " + prog + " " + args + "'");

that converts args array to a string using join(",") by default. It could be easily fixed by joining them manually:

util.debug("Starting child process with '" + exec + " " + prog + " " + args.join(" ") + "'");

Ah, cool. So I'll consider this an issue that has a workaround, but could definitely benefit from a friendlier solution.

That's weird that foreman is choking on it. You're running from a Procfile, I assume? You could ask them if that's intended behavior.


Hi, thank for the tip. I works well excepted that launching

  supervisor -e "coffee|node|js" -x coffee -- --nodejs --debug

hangs when I modify one of the application files. I got the message DEBUG: crashing child, then nothing happens. Would it be related ?


Hmm, interesting. It looks like somehow coffeescript or the --nodejs option is causing a bug. I opened #51 to deal with that.

@iangreenleaf iangreenleaf added a commit that referenced this issue May 2, 2012
@iangreenleaf iangreenleaf Program is just a big array of args now.
Fixes #51.

Also fixes some debugging glitches mentioned in #49.

I had another think about this. Here's my new idea, lemme know how this feels: we could offer a wildcard flag, --x-foo, where anything after the --x- gets passed in as a -- argument to the child.

supervisor --x-debug-brk server.js #=> node --debug-brk server.js
supervisor --x-node-debug-brk #=> coffee --node-debug-brk

I'm thinking it would either be --x-foo (to match the -x option), or --child-foo (for obvious reasons).


not sure if this is still an issue but i was able to get going on windows without modifying supervisor code via the cli-wrapper.js

start cmd.exe /k "node-inspector"
start cmd.exe /k "node node_modules\supervisor\lib\cli-wrapper.js -w .,node_modules,node_modules/custom_modules -- ""--debug-brk ./././index.js"""

the first line is just to start the node-inspector
basically escaped the program param with double quotes: -- ""--debug-brk ./././index.js"""
make sure that the program parameter is passed in with double dash and space in front


Will track future progress on options in #123.

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