Set process.execPath correctly when running .coffee files

[TrevorBurnham]

Issue #1303 set process.argv[0] to coffee. However, process.execPath still gives the absolute path of node, not coffee. This patch corrects that by using the value of __filename from coffee as process.execPath when running a .coffee file.

[michaelficarra]

I'm for fixing it, but I believe there are better fixes than changing run's signature. For example, we could instead add either process.execPath = process.mainModule.filename or process.execPath = process.argv[1] before process.ARGV = process.argv = process.argv.slice(0, 2).concat opts.literals (line 68).

[TrevorBurnham]

Great idea! I was unaware of process.mainModule. That makes it a simple 1-line addition in command.coffee.

[michaelficarra]

Before you commit to that, make sure process.mainModule is part of the public API. require.main.filename or module.filename or process.argv[1] may be a better choice.

[jashkenas]

None of those alternatives are documented in Node's public API, so I think this is fine for now.

[michaelficarra]

None of those alternatives are documented in Node's public API

process.argv[1]

[jashkenas]

process.argv[1] isn't the absolute path to the coffee executable.

[michaelficarra]

process.argv[1] isn't the absolute path to the coffee executable.

It is before we rewrite it. (test.coffee contains console.log process.argv and I added console.log process.argv to src/command.coffee right before we rewrite process.argv)

[ 'node',
  '/home/michael/projects/coffee-script/bin/coffee',
  '/home/michael/test.coffee' ]
[ 'coffee', '/home/michael/test.coffee' ]

which happens at the current line 68, the line I suggested we add the fix above... above.

edit: various inline edits

[TrevorBurnham]

That works too. For the record, require.main is part of Node's public API and should be equivalent to process.mainModule. (I asked here.)

[jashkenas]

Thanks for asking ... moved to require.main at 08294dc