Set process.argv[0] to 'coffee' when using coffee foo.coffee

[TrevorBurnham]

As discussed at #1301 (and several other issues Michael linked to from there), the current behavior of process.argv is to preserve 'node' as the first array value. I wasn't convinced that this mattered when the issue was first raised, but I've since come around. The very purpose of argv is that it tells you how to run the current program; if you run

coffee foo.coffee

and process.argv is

['node', 'foo.coffee']

then you can't do that. It's internally inconsistent, and in practical terms, it means you can't use raw coffee files with libraries like multi-node (see #1283) and Cluster, which use process.argv to fork processes. Granted, it's a good practice to compile to JS before deployment in such an environment, but there are circumstances under which using coffee files directly is much more convenient. I see no advantage to the current behavior.

[satyr]

Is .run meant to be public as a module method? If so, this seems problematic:

$ cat 1303.js
console.log(process.argv[0])
require('coffee-script').run('', {})
console.log(process.argv[0])

$ node 1303.js
node
coffee

[jashkenas]

As always, @satyr is right on the money. The above fix puts the coffee argv in the right place -- for anything that's run by the coffee command, and nowhere else.

[satyr]

This fix seems leaky still:

$ /usr/local/bin/coffee -e 'console.log process.argv[0]'
node

$ /usr/local/bin/coffee -s <<_
> console.log process.argv[0]
> _
node

$ echo console.log process.argv[0] > t.coffee && \
> /usr/local/bin/coffee t.coffee
coffee

where:

$ /usr/local/bin/node -e 'process.argv[0]'
/usr/local/bin/node