Added CoffeeScript support

[simonexmachina]

There's several ways that we could do this, but I'm not sure what your preference is so I've implemented how I think it should be supported: if .coffee is included in require.extensions then enrouten will load CoffeeScript files.

Other options include opt-in using a configuration option, or the ability to specify the set of extensions to be loaded in the config.

[totherik]

I'm not in love with adding custom extension support here. All I see is maintenance burden. Would something like the following suffice?

function tryResolve(file) {
    try {
        // implicitly uses require.extensions to resolve known file types
        // json would be a noop since JSON files don't fulfill the required
        // exported function API
        file = file.replace(path.extname(file), '');
        require.resolve(file); 
        return true;
    } catch (err) {
       return false;
    }
}
// ... snip ...

} else if (stats.isFile() && tryResolve(file)) {

// ... snip ...

[simonexmachina]

Yup, that's a good suggestion. I've done that an pushed.

[totherik]

The sample code isn't very robust and should be improved before merging. For example, if file is something like /Users/me/src/git/myapp.js/routes/index.js this code will cause unexpected results.

Thanks for being so responsive @aexmachina.

[simonexmachina]

Maybe I don't understand, but I'm not aware of any issue with using require
with an absolute path? I just did a test with /tmp/foo.js and
require('/tmp/foo') and it worked fine.

[lmarkus]

@totherik's comment was pointed toward the code behavior. In his example, .js appears twice in the filename (Once as the extension, once as part of the path). Doing a replace operation on the extension would alter the path as well.

Think about all the weird stuff that "clever" developers will come up with. 😆

[simonexmachina]

Okay, gotcha. Good point, have pushed a more robust version.

[totherik]

I was thinking some more along the lines of:

file.replace(new RegExp(path.extname(file) + '$'), '');

[simonexmachina]

Yes, I considered that but then you'd need to escape the . and JavaScript doesn't have a RegExp.escape() function. Happy to do it that way though, have updated.

I also tested some assumptions about how path.extname() works, and it is sensible.

[totherik]

Yeah, I don't want to be in the business of maintaining naive extension parsing regexes when I can rely on extname. It may not be a bad idea to have an explicit test case for this feature at this point. Consider this:

'use strict';

var path = require('path'),
    assert = require('assert');

function a(file) {
    var ext = path.extname(file);
    if (ext) {
        return file.replace(new RegExp('\\' + ext + '$'), '');
    }
    return file;
}

function b(file) {
    return file.replace(/\.[a-z]+$/i, '');
}

['', '.js', '.coffee', '.', '.pk12'].forEach(function (ext) {
    var expected, original;

    expected = path.join(__dirname, 'foo');
    original = expected + ext;

    assert.equal(a(original), expected, 'implementation a failed to parse ' + original);
    assert.equal(b(original), expected, 'implementation b failed to parse ' + original);
});

Function b fails for both . and .pk12. The rationale is not that I need to handle those cases, but that I don't need to worry about them or predict my inputs because I can consistently parse them. I KNOW the generated regex will work, while I can't be sure the basic regex will.

[simonexmachina]

Yes I couldn't agree more. My latest commit (when I posted my last comment) didn't actually push, so you couldn't see it after my previous commit. Basically I have used extname() and have confirmed that it handles those edge cases. I added a test for them as well but removed it, I can re-add if you like.

[totherik]

This looks good to me. One last question: you actually tested this with coffeescript, right? 😄 I don't have it configured to actually try out so I want to make sure at least one person has tested ensure this code change resolve this particular issue. Thanks, again, for your work on this @aexmachina

[lmarkus]

Just one last request from me. @aexmachina, would you mind contributing a simple example along the vein of what's in the krakenjs.com examples section? I'd be happy to link to it

[simonexmachina]

Tested in CoffeeScript - yes, I've been using it with CoffeeScript.

Not sure what the example would be - it's exactly the same as JavaScript. I've updated README.md with some info. Feel free to suggest any other additions.

[totherik]

Either way, 👍 from me.

[lmarkus]

Kraken now supports CoffeeScript 👍
Thanks @aexmachina

[simonexmachina]

Go team!