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    Fluent pluggable interface for easily wrapping describe, context, it, and specify blocks in Mocha tests.


    var wrap = require('mocha-wrap');
    var expect = require('chai').expect;
    var mockWindow = {
        location: {
            href: 'test/url'
    wrap().withGlobal('window', () => mockWindow).describe('mocked window', function () {
        it('is mocked', function () {
        it('has the right URL', function () {
    var obj = { a: 1 };
    wrap().withOverrides(() => obj, () => ({ a: 2, b: 3 })).describe('overridden object keys', function () {
        it('has "b"', function () {
        it('has overridden "a"', function () {
    wrap().withOverride(() => obj, 'a', () => 4).skip().describe('this test is skipped', function () {
        it('also supports .only()!', function () {
            expect(true).to.equal(false); // skipped


    A mocha-wrap plugin is a named function that returns a MochaWrapper instance or a descriptor object.

    • A plugin’s function name must begin with the string “with”.

    • Plugins can be globally registered, or .used ad-hoc.

    • .use requires a plugin function as its first argument; further arguments are passed through to the plugin.

    • .extend requires a non-empty description string, and a descriptor object which may contain a value that is a function, or an array of functions, whose keys correspond to any or all of the supported mocha methods.

    • Globally registered plugins, .use calls, and .extend calls can be chained, stored, and reused - each link in the chain creates a new instance of a MochaWrapper.

    • A descriptor object may contain any or all of these 5 keys:

    • a description string, for use in “describe” and/or “it” (this is required when returning an object)

    • beforeEach: a function, or array of functions, for use in a mocha beforeEach function

    • afterEach: a function, or array of functions, for use in a mocha afterEach function

    • before: a function, or array of functions, for use in a mocha before function

    • after: a function, or array of functions, for use in a mocha after function

    The most common approach will be for a plugin function to return this.extend(description, descriptor).

    A plugin function must have a name that starts with “with”, and will be invoked with a receiver (”this” value) of a MochaWrapper instance.

    To register a plugin, call the register function on mocha-wrap with the plugin function. This should not be done in a reusable module.

    module.exports = function withFoo(any, args, you, want) {
        return this.extend('with some foo stuff', {
            beforeEach: function () {
                // setup ran before each test
            afterEach: [
                function () {
                    // teardown ran after each test
                function () {
                    // more teardown
            before: function () {
                // setup ran once before all tests
            after: function () {
                // teardown ran once after all tests


    var wrap = require('mocha-wrap');


    Although mocha has describe.skip, describe.only, context.skip, context.only, it.skip, it.only, specify.skip, and specify.only, it is not possible to implement these in mocha-wrap without using ES5 property accessors. Since this project supports ES3, we decided to use .skip().describe etc rather than forfeit the ability to have skip/only.


    Simply clone the repo, npm install, and run npm test


    npm i mocha-wrap

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