instrument.js hangs sometimes in node v5

[esbena]

Possibly related: #58

instrument.js hangs in node v5

To reproduce:

$ node --version
v5.0.0
$ mkdir test
$ cd test
$ echo '{}' > package.json
$ npm i jalangi2
$ npm i minimist
$ node node_modules/jalangi2/src/js/commands/instrument.js --outputDir out node_modules/minimist
^C # it hangs..
$ rm -rf node_modules/minimist/test
$ node node_modules/jalangi2/src/js/commands/instrument.js --outputDir out node_modules/minimist
instrumenting out/minimist2/index_orig_.js
instrumenting out/minimist2/example/parse_orig_.js
done!

It seems that the call to ncp on line 454 of instrument.js never calls the callback.
That can be shown with the following change:

ncp(inputDir, copyDir, {transform: transform}, function(){console.log('ncp done')});

[msridhar]

Does it work with v4? In the short-term probably downgrading node is your best bet. I think the right fix is to get rid of our dependence on ncp entirely. One simple solution is to do the following instead:

1. First just do a simple cp -r to the output directory (there must be a robust library for this).
2. Go through the output directory and replace files with their instrumented versions.

I think that will be a lot more robust and conceptually simple than what we do now.

[esbena]

https://www.npmjs.com/package/graceful-ncp is a drop-in replacement for ncp, just use require('graceful-ncp') instead.
The issue is fixed if instrument.js is modified to use that instead of ncp.

I will make a pull-request when I have tested this fix for some time.

[msridhar]

Fixed by 619d5d2