Dependency injection in node

loadModule.js

/**
 * Loads a module with the means to inject mocks.
 * Usage:
 *   module = require('module-name');                  // old and busted
 *   module = loadModule('/path/to/module-name.js', {  // new hotness
 *      'mocked-module-name': {}
 *   });
 *
 * Thanks to: http://howtonode.org/testing-private-state-and-mocking-deps
 *
 * @param {string} filePath Path to the module (must be absolute path to module file)
 * @param {object} mocks    Mocks to inject
 * @return {object} Module
 */
loadModule = function (filePath, mocks) {
    var exports = {},
        context,

        /**
         * Resolve the module path, allowing for paths relative to the current module.
         *
         * @param {string} module Path to the module
         * @return {string}
         */
        resolveModule = function (module) {
            if (module.charAt(0) !== '.') {
                return module;
            }

            return path.resolve(path.dirname(filePath), module);
        },

        /**
         * Require a module, replacing the real one with a mock if it exists.
         *
         * @param {string} module Path to the module
         */
        requireModule = function (module) {
            var name = path.basename(module, '.js');

            return mocks[name] || require(resolveModule(module));
        };

    mocks = mocks || {};
    context = {
        require: requireModule,
        console: console,
        exports: exports,
        module: {
            exports: exports
        }
    };

    vm.runInNewContext(fs.readFileSync(filePath), context);

    return context.module.exports;
};