Support SourceMap

[gfx]

There comes more and more JavaScript source generation tools.
If nodejs support SourceMap, we'll be very happy. On Browsers, Chrome (19+) supports SourceMap and it works well.
(cf. INTRODUCTION TO JAVASCRIPT SOURCE MAPS)

(This ticket might be related to #2537)

[bnoordhuis]

What's stopping you from writing a sourcemap module and publishing it on npm? I don't think there's anything in the sourcemap spec that requires it to be the a core module but please correct me if I'm wrong.

[gfx]

I'm sorry to my lack of explanations. I didn't mean to need sourcemap modules. There is already a stable sourcemap module: https://github.com/mozilla/source-map

Rather, I'd like to node to understand source-mapping information. How can we see correct line numbers and file names in runtime error messages when we use CoffeeScript? That's sourcemap and it is the interpreter which can process source-mapping files.

[bnoordhuis]

Why would node need to do anything? Isn't that the task of the CS loader?

[gfx]

CoffeeScript is just an example and I doesn't use CS actually, sorry.

What I use is Google Closure Compiler and JSX, which are also support sourcemap output.

[bnoordhuis]

Okay, thanks - that kind of clears it up for me. I doubt anyone on the core team has the time or the inclination to work on this but we'll entertain patches. I'll reopen the issue.

[gfx]

Thank you very much! Anyway, it is the first step.

[martinheidegger]

Right now having no correct file number of stacktraces from code created by the is annoying at best. I would very much welcome this feature: +1

[eldargab]

+1

[Lewuathe]

We'll be able to get more debug options on node development +1

[SystemParadox]

+1, I've even made my own language that extends JavaScript, that's how common this is becoming

[devongovett]

Here is a module that implements sourcemap support in user land https://github.com/evanw/node-source-map-support

[jashkenas]

FWIW, it looks like @evanw's implementation is fairly minimal, and would probably be a good starting point for getting a patch landed into core: https://github.com/evanw/node-source-map-support/blob/master/source-map-support.js

... this would also help for development in terms of bringing the Node debugger closer to browser debuggers in terms of feature parity -- making it a bit more viable to develop and test libraries in just Node instead of in Chrome.

[TooTallNate]

Because of the hacky way that this needs to be integrated into the V8 internal API, it seems to me that this belongs at the V8 level rather than node...

[gfx]

There's an npm to support source-map: https://github.com/evanw/node-source-map-support

I'd like to merge node-source-map-support into the NodeJS core.

[fresheneesz]

It doesn't seem like evanw's node-source-map-support gives any real support for debugging. Is this issue about stack traces and debugging, or just the former?

[gfx]

@fresheneesz Ideally, yes, but partial support is better than nothing.

[realyze]

+1 this

[doublerebel]

👍

[jnordberg]

👍

[kenjiru]

Sourcemaps support would be really nice for debugging TypeScript modules. Thanks!

[patrickmesana]

+1

[misterdai]

👍 Would love sourcemap support. Currently using Traceur to transpile ES6/7 for Node, which can produce the sourcemap files but I can't make use of them.

[gsikorski]

+1 For production server it is nice to browserify + minify the code of the backend as well (even including all node_modules installation), so that it occupies less space. Would be great if node supports printing the stack using provided source map.

[bnoordhuis]

Closing, continues in nodejs/node#6471.