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Latest commit 72a0503 Jul 18, 2018

Marko CLI

Developer tools for Marko.


Requires Node 6+

Global installation:

npm install marko-cli --global

Local installation:

npm install marko-cli --save-dev


marko <command> arg0 arg1 ... argn


marko test src/components/app-foo

Command line interface (CLI)

Core commands


Used to create a template Marko project in a specific directory.


Create a Marko project in the current directory:

marko create myapp

Create a Marko project in a specific directory:

marko create myapp --dir /Users/me/Desktop


Used to run unit tests for UI components. marko test supports glob patterns for locating and running test files. See Component Testing below for more details on how to write unit tests for UI components.


Run all of the tests in a project/directory:

marko test

Run all of the unit tests for a single UI component:

marko test ./src/components/app-foo/**/test*.js

Run all of the unit tests for all UI components:

marko test ./src/components/**/test*.js

Run only server tests:

marko test ./src/components/**/test*server.js --server

All node options are forwarded to the mocha process for server testing, allowing the following:

# Will start a debugging session on the spawned mocha process.
marko test --server --inspect-brk

Component testing

Marko CLI includes a testing framework (built on top of mocha) that targets UI components built using Marko or Marko Widgets. Each UI component may include test files alongside components or in a test/ directory that consists of one or more JavaScript test files with a name in any of the following formats:

  • test.js - runs only in the browser
  • test.server.js or test-server.js - runs only on the server
  • test.browser.js or test-browser.js - runs only in the browser

An optional prefix can also be provided for grouping tests:

  • foo.test.js or foo-test.js
  • foo.test.server.js or foo-test-server.js
  • foo.test.browser.js or foo-test-browser.js

Below is a sample set of tests:

/* globals test */

var expect = require("chai").expect;

test("variant-danger", function(context) {
  var output = context.render({ variant: "danger" });

// A similar test can be done using jQuery selectors (powered by cheerio):
test("variant-info", function(context) {
  var output = context.render({ variant: "info" });
    "app-button app-button-info"

// Async test:
test("my async test", function(context, done) {
  setTimeout(function() {
  }, 100);

// Use test.only to only run a single test:
test.only("foo", function(context) {
  // ...

// Use test.skip to skip tests
test.skip("bar", function(context) {
  // ...

Component testing API


it(desc, [done])

test(desc, context[, done])

test.only(desc, context[, done])

test.skip(desc, context[, done])


render(data) : RenderResult



Returns a jQuery-compatible object for querying the rendered DOM. Utilizes cheerio.


The output HTML string.


In-browser only

Returns a rendered instance of the component.


In-browser only

This is an alias for the above component getter.


When a component is rendered, a snapshot of the HTML output will automatically be saved into the test/snapshots/ directory. This directory should be excluded from source control. For example:



Code coverage

Use nyc to generate coverage reports. Just prefix any test commands with nyc:

nyc marko test


Marko CLI supports plugins as JavaScript functions:

module.exports = function(markoCli) {
  // Run any initialization code:

  // Register new commands...
  // Add support for: `marko my-command arg0 arg1 ... argn`
  markoCli.addCommand("my-command", {
    run(options) {
      return new Promise((resolve, reject) => {
        // Run the command

    parse(args) {
      var options = {};
      return options;



You can provide a package-specific plugin by creating a marko-cli.js file at the root of your project:


module.exports = function(markoCli) {
  // ...

A package-specific plugin will automatically be loaded when marko is launched.

Some options can be specified on the config object that markoCli exposes.

For example, shared test dependencies can be specified with the dependencies option.

module.exports = function(markoCli) {
  markoCli.config.browserTestDependencies = [
    "require-run: ./tools/myDependency.js"

For more info on how to specify dependencies can be found here.

Configuring Lasso

Lasso plugins and transforms can also be specified using the lassoOptions option.


module.exports = function(markoCli) {
  markoCli.config.lassoOptions = {
    plugins: [
      "lasso-less" // Marko plugin is included by default.
    require: {
      transforms: [
          transform: "lasso-babel-transform"

Configuring Mocha

You can easily configure Mocha for server-side tests using markoCli.config.mochaOptions. Supported mocha options, and should be written in camel case:


module.exports = function(markoCli) {
  markoCli.config.mochaOptions = {
    timeout: 5000,
    colors: true

Browser Testing with

Under the hood marko test uses to speak to various browsers. The test command operates differently than a standard WDIO utility by compiling the tests themselves and running everything in the browser. A websocket is setup with the browser instance to stream logs. A subset of WDIO options are exposed under markoCli.config.wdioOptions.


module.exports = function(markoCli) {
    markoCli.config.wdioOptions = {
         * Capabilities are always run in parallel.
         * By default chromedriver will be used if capabilities are left blank.
        capabilities: ...,
        serverPort: 0, // The port to start the test server on (serves your components).
        idleTimeout: 60000, // Automatically disconnect after 1min of inactivity by default.
        suiteTimeout: 600000, // Automatically disconnect after 10 minutes if the tests have not completed by default.
        viewport: {
          // Configure the screen size for any drivers started (defaults below).
          width: 800,
          height: 600
         * The launcher option allows you change the WDIO config before running, and cleanup afterward.
         * By default the chromedriver is launched, however if `BROWSERSTACK_USERNAME`, `SAUCE_USERNAME`
         * or `TB_KEY` is found in the environment variables a service for that provider will automatically be used.
        launcher: {
            onPrepare(config, capabilities) {
                // Setup WDIO config.
            onComplete() {
                // Cleanup after tests.


  • Don't write compiled templates to disk
  • Allow mocks for custom tags
  • File watching when running tests
    • marko test --watch
  • Helper API for simulating DOM events
  • Plugin API for adding helpers to context
  • In-browser UI component viewer with file watching
    • Drop down for inputs
    • Editor for input data
  • In-browser project explorer (with links to run browser tests and view UI components)
  • Image snapshots
  • Testing in jsdom
  • Launching tests in multiple browsers (both headless and real browsers)