Iterate all the files

0usage.js

var iterateFiles = require("iterateFiles"),
    path = require("path")

// Load all files in the test folder or any of their sub folders
iterateFile(path.join(process.cwd(), "./test"), function (fileName) {
    // run code for each recursively found js file
}, function (err) {
    // run code when all files have been found recursively
})

fileIterator.js

var fs = require("fs"),
    path = require("path"),
    isJsFile = /.js$/

function iterateFiles(uri, callback, done) {
    var counter = 1
    fs.readdir(uri, errorProxy(done, readFiles))

    function readFiles(err, files) {
        counter += files.length
        files.forEach(isDirOrFile)
        next()
    }

    function isDirOrFile(fileName) {
        fileName = path.join(uri, fileName)

        fs.stat(fileName, errorProxy(done, readOrRecurse))

        function readOrRecurse(err, stat) {
            if (stat.isDirectory()) {
                iterateFiles(fileName, callback, errorProxy(done, next))
            } else if (stat.isFile() && isJsFile.test(fileName)) {
                callback(fileName)
                next()
            } else {
                next()
            }
        }
    }

    function next() {
        if (--counter === 0) {
            done(null)
        }
    }
}

function errorProxy(errorHandler, callback) {
    return proxy

    function proxy(err) {
        if (err) {
            return errorHandler(err)
        }
        return callback.apply(this, arguments)
    }
}

I think you should pass the error to the done callback, not the per file callback.

Really not sure what's ideal in this situation.

Abort on error and call done callback with this error?

On line 30 you must check for an error passed to next.

Thanks, fixed the error handling to be better

Nice, two comments:

1. I don't think you should hard code the regexp. What if people want to require coffee script files or whatever? Or maybe all files ending with .run.js. You could add an optional regexp parameter which defaults to the one you have hardcoded now when not supplied.
2. Wouldn't it be more descriptive to rename error() to errorProxy()? At first I didn't realize it was a proxy.

1. People who want coffee can go die. Not adding complexity to the code for the sake of having flexibility on the regexp.

In that case you should rename iterateFiles to iterateJSFiles or whatever? Actually a much better argument is that people may want to iterate over non-js files, such as .txt files or whatever.

See https://gist.github.com/2687636