async-runner.js

var _     = require('./vendor/underscore'),
    spawn = require('child_process').spawn;

var log = function (message, newline) {
    if (newline === undefined) { newline = true; }
    process.stdout.write('[' + Date.now().toString() + '] ' + message + (newline ? '\n' : ''));
    return;
};

// Stores the exit codes for each test runner.
var results = {};

// Handles exiting the process when all test runners have been completed.
var resume = function () {
    // If all of the exit codes have been defined, we are ready to exit.
    if (_.all(results, function (value, key) { return value !== undefined; })) {
        var success = _.all(results, function (value, key) { return value; });
        process.exit(success ? 0 : 1);
    }
};

// Spawns a new test runner.
var spawnRunner = function (options) {
    var child = spawn.apply(this, options.args);
    results[options.name] = undefined;
    log(options.name + ': Starting test suite... (PID: ' + child.pid + ')');
    
    // Replay any data caught in the child processes to stdout
    var writeData = function (data) { log(options.name + ': ' + data, false); };
    child.stdout.on('data', writeData);
    child.stderr.on('data', writeData);
    
    // Whenever the child exits, update the 
    child.on('exit', function (code, signal) {
        results[options.name] = (code === 0 ? true : false);
        log(options.name + ': Finished test suite with exit code: ' + code + ' ' + ((code == 0) ? 'SUCCESS' : 'FAILURE'));
        resume();
    });
};  

spawnRunner({name: 'Django', args: ['echo', ['asdf']]});
spawnRunner({name: 'Node', args: ['echo', ['asdf']]});