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JAVASCRIPT DEVELOPER Ultimate Exam
Question 1. Which file in a Magento 2 theme is primarily responsible for configuring RequireJS paths and shims for custom JavaScript? A) requirejs-config.js B) module.js C) mixins.xml D) webpack.config.js Answer: A Explanation: The requirejs-config.js file located under view/frontend/requirejs- config.js or view/adminhtml/requirejs-config.js defines module paths, shims, and map configurations for RequireJS in Magento. Question 2. In RequireJS, what does the “shim” configuration allow you to do? A) Load AMD-compatible modules asynchronously B) Define dependencies for non-AMD scripts and export a global variable C) Minify JavaScript files automatically D) Register a module under a different name Answer: B Explanation: A shim tells RequireJS about scripts that do not call define(), specifying their dependencies and the global variable they export. Question 3. Which of the following is the correct syntax to define a Magento 2 AMD module that depends on jQuery and underscore? A) define(['jquery','underscore'], function ($, _) { … }); B) require(['jquery','underscore'], function ($, _) { … }); C) module('jquery','underscore', function ($, _) { … }); D) import $ from 'jquery'; import _ from 'underscore'; Answer: A Explanation: Magento 2 uses AMD; the define() function lists dependencies and provides them to the callback. Question 4. What is the purpose of the map section in a requirejs-config.js file?
JAVASCRIPT DEVELOPER Ultimate Exam
A) To replace one module with another throughout the application B) To define the order in which modules are loaded C) To set up CSS preprocessing rules D) To create a shortcut for long module names Answer: A Explanation: The map configuration can redirect requests for a specific module ID to a different implementation, useful for overriding core modules. Question 5. Which Underscore.js method creates a compiled template function from a string? A) _.each B) _.template C) _.extend D) _.isObject Answer: B Explanation: _.template takes a string with interpolation tags and returns a function that can be called with a data object to produce HTML. Question 6. How can you use an Underscore template inside a Magento 2 .phtml file? A) By calling $block->getTemplateHtml() B) By embedding the template string in a
JAVASCRIPT DEVELOPER Ultimate Exam
A) app/code/Vendor/Module/view/frontend/web/js/ B) app/code/Vendor/Module/etc/frontend/ C) app/design/frontend/Vendor/theme/web/js/ D) lib/internal/Magento/Framework/View/Asset/js/ Answer: A Explanation: view/frontend/web/js is the standard path for frontend JavaScript assets in a module. Question 11. How do you declare a mixin for the core mage/validation module? A) Add a mixins.xml file under view/frontend/etc/ with the target and mixin paths B) Edit requirejs-config.js and add a mixins section C) Create a module.js file that extends the target class D) Use the @magentoMixins annotation in the JavaScript file Answer: B Explanation: Mixins are configured in requirejs-config.js under the mixins section, mapping the target module to the mixin file. Question 12. In a Magento 2 JavaScript module, what does module.exports represent? A) The global variable exported to the window object B) The object returned by the AMD define callback, exposing public methods C) The list of dependencies for the module D) The configuration for the RequireJS optimizer Answer: B Explanation: In AMD, the value returned from the define() callback (often assigned to module.exports) becomes the module’s public API. Question 13. Which browser developer tool panel is most useful for inspecting KnockoutJS bindings in Magento 2? A) Network panel B) Elements panel with the ko-binding extension (if installed)
JAVASCRIPT DEVELOPER Ultimate Exam
C) Console panel only D) Performance panel Answer: B Explanation: The Elements panel shows the DOM, and with the Knockout extension you can view active data-bind expressions; otherwise, the console can be used to evaluate view models. Question 14. What Magento 2 JavaScript utility provides a global registry for sharing data between components? A) mage/registry B) mage/dataStore C) mage/cache D) mage/transport Answer: A Explanation: mage/registry allows components to register and retrieve shared objects by key. Question 15. How do you retrieve a previously registered component from the mage/registry? A) registry.get('componentName'); B) mage.registry('componentName'); C) $.registry('componentName'); D) require('mage/registry').fetch('componentName'); Answer: A Explanation: The get method of the registry returns the stored instance. Question 16. Which of the following statements about Magento 2 “mage widgets” is true? A) They are pure vanilla-JS classes unrelated to jQuery UI B) They wrap jQuery UI widgets and provide Magento-specific configuration options C) They can only be initialized via XML layout files
JAVASCRIPT DEVELOPER Ultimate Exam
Answer: B Explanation: customer-data stores data sections in localStorage and updates them via AJAX when the server signals invalidation. Question 20. How can you force a refresh of the “cart” section from JavaScript? A) customerData.reload(['cart']); B) customerData.invalidate(['cart']); C) customerData.set('cart', {}); D) customerData.refresh('cart'); Answer: A Explanation: customerData.reload() accepts an array of section names to re-fetch from the server. Question 21. Which of the following is NOT a valid data-binding attribute used in Magento UI component templates? A) afterRender B) visible C) dataScope D) bindOnce Answer: D Explanation: bindOnce is not a built-in Magento binding; common bindings include visible, text, value, afterRender, event, etc. Question 22. In a UI component XML file, which attribute defines the JavaScript component that will render the UI element? A) component B) class C) jsComponent D) type Answer: A
JAVASCRIPT DEVELOPER Ultimate Exam
Explanation: The component attribute points to the AMD module responsible for the UI component’s behavior. Question 23. What does the uiComponent module provide for Magento 2 UI components? A) A base class that handles initialization, data binding, and lifecycle events for all UI components B) A CSS framework for styling components C) Server-side validation of UI data D) Automatic translation of UI strings Answer: A Explanation: uiComponent is the base JavaScript class that all UI components extend, offering common functionality. Question 24. Which XML node is used to declare a data source for a form UI component? A) B) C) D) Answer: C Explanation: The node defines the data provider (usually a class extending Magento\Ui\DataProvider) for forms and grids. Question 25. In an admin grid UI component, how do you change the renderer of a column to a custom Knockout template? A) Set the template attribute of the column to the template file path B) Add a renderer node with the fully qualified class name C) Use the component attribute on the column D) Define a bodyTmpl property in the column configuration Answer: D
JAVASCRIPT DEVELOPER Ultimate Exam
Question 29. Which Knockout binding is used to iterate over an observable array in a checkout template? A) foreach B) repeat C) each D) loop Answer: A Explanation: The foreach binding repeats a block of markup for each item in an observable array. Question 30. To listen for changes in the shipping address observable, which method should you use? A) shippingAddress.subscribe(callback); B) shippingAddress.on('change', callback); C) shippingAddress.watch(callback); D) shippingAddress.addListener(callback); Answer: A Explanation: Knockout observables provide a subscribe method that fires when the observable’s value changes. Question 31. Which of the following is the correct way to extend a core Knockout component using a mixin? A) Add a mixins section in requirejs-config.js targeting the component’s AMD path B) Create a in di.xml for the JavaScript class C) Override the template file in your theme D) Use $.extend in the component’s JavaScript file Answer: A Explanation: JavaScript mixins are configured via requirejs-config.js under the mixins section, allowing you to augment any AMD module.
JAVASCRIPT DEVELOPER Ultimate Exam
Question 32. In Magento 2, which method of the customer-data module is used to store custom data into a section? A) set('sectionName', data) B) add('sectionName', data) C) update('sectionName', data) D) assign('sectionName', data) Answer: A Explanation: customerData.set() stores the provided data under the specified section name. Question 33. Which of the following is the correct syntax to register a new UI component in a layout XML file? A) B) C) D) Answer: C Explanation: UI components are added inside a container (e.g., content) using the node with name and component attributes. Question 34. What is the purpose of the afterRender binding in a Magento UI component template? A) To execute a JavaScript function after the element is inserted into the DOM B) To delay rendering until data is loaded C) To bind a click event to the element D) To replace the element’s HTML after rendering Answer: A Explanation: afterRender receives a callback that runs after Knockout finishes rendering the element.
JAVASCRIPT DEVELOPER Ultimate Exam
Question 38. Which Magento 2 JavaScript module provides utilities for handling URLs and query parameters? A) mage/url B) mage/uri C) mage/link D) mage/path Answer: A Explanation: mage/url contains build and parse functions for constructing and dissecting URLs. Question 39. In a RequireJS-based Magento module, what does the 'text!' prefix in a dependency path indicate? A) The file should be loaded as plain text (e.g., HTML template) B) The file is a CSS stylesheet C) The file must be minified before loading D) The file is a JSON configuration file Answer: A Explanation: text! is a RequireJS plugin that loads the referenced file as a string, commonly used for HTML templates. Question 40. Which method is used to programmatically trigger a UI component’s reload function? A) reload() B) refresh() C) update() D) reinitialize() Answer: A Explanation: Many UI components expose a reload() method to re-fetch data from their data source.
JAVASCRIPT DEVELOPER Ultimate Exam
Question 41. What is the correct way to add a custom JavaScript file to the checkout page without modifying core files? A) Add it to view/frontend/web/js/checkout-custom.js and reference it in checkout_index_index.xml via a node B) Place it in pub/static/checkout-custom.js directly C) Edit vendor/magento/module-checkout/view/frontend/layout/checkout_index_index.x ml and add a
JAVASCRIPT DEVELOPER Ultimate Exam
Answer: B Explanation: Mapping the core module to a stub (e.g., 'empty': true) effectively disables it. Question 47. Which of the following is NOT a standard Magento UI component type? A) form B) listing C) chart D) dataSource Answer: C Explanation: Magento does not ship a built-in chart UI component; form, listing, dataSource are standard. Question 48. When creating a custom Knockout component, which file extension should be used for the HTML template? A) .html B) .phtml C) .tpl D) .tmpl Answer: A Explanation: Knockout templates are plain HTML files referenced via template: 'Vendor_Module/template/my-component' and loaded with the text! plugin. Question 49. Which method in the Magento_Checkout/js/model/quote module returns the current shipping address? A) getShippingAddress() B) getAddress() C) getShippingAddressData() D) getShippingInfo() Answer: A
JAVASCRIPT DEVELOPER Ultimate Exam
Explanation: quote.getShippingAddress() provides the observable object representing the shipping address. Question 50. In the checkout, which component is responsible for calculating totals on the client side? A) Magento_Checkout/js/model/totals B) Magento_Tax/js/model/tax-calculation C) Magento_Sales/js/model/order-total D) Magento_Checkout/js/action/calculate-totals Answer: A Explanation: Magento_Checkout/js/model/totals stores and updates the totals observable after each change. Question 51. Which of the following is the correct way to extend a core Magento UI component using a JavaScript mixin? A) In requirejs-config.js, add mixins: { 'Magento_Ui/js/form/form': { 'Vendor_Module/js/form-mixin': true } } B) Create a plugin in di.xml for the JavaScript class C) Override the component’s template in your theme D) Use jQuery’s $.extend inside the component’s init function Answer: A Explanation: The mixins section maps the target AMD module to the mixin file. Question 52. Which data-binding attribute would you use to bind a Knockout observable to an input’s value and also update the observable when the user types? A) value B) text C) click D) enable Answer: A
JAVASCRIPT DEVELOPER Ultimate Exam
Explanation: mage/debounce exposes a debounce function to limit how often a callback runs. Question 56. In a Knockout template, how do you conditionally display an element only when an observable isVisible is true? A) … B) … C) Both A and B are correct D) Neither; you must use a computed observable Answer: C Explanation: Both the comment-style if binding and the visible binding achieve conditional rendering. Question 57. Which method of the mage/translate module is used to translate a string on the client side? A) $t('String') B) translate('String') C) i18n('String') D) __('_String') Answer: A Explanation: $t is the shortcut function provided by mage/translate to fetch the translated version of a string. Question 58. What is the purpose of the mage/validation module in Magento 2? A) To provide client-side form validation rules and error display mechanisms B) To validate server-side API responses only C) To encrypt form data before submission D) To generate CSRF tokens for forms Answer: A Explanation: mage/validation adds validation rules to form fields and displays error messages without a page reload.
JAVASCRIPT DEVELOPER Ultimate Exam
Question 59. Which of the following options correctly disables a UI component’s sortable feature via XML? A) false B) C) 0 D) no Answer: A Explanation: The node holds component configuration; setting sortable to false turns off the feature. Question 60. In a Magento 2 theme, where would you place a custom requirejs- config.js to override a core module’s path? A) app/design/frontend/Vendor/theme/requirejs-config.js B) app/design/frontend/Vendor/theme/web/requirejs-config.js C) app/code/Vendor/Theme/Requirejs/requirejs-config.js D) app/design/frontend/Vendor/theme/etc/requirejs-config.xml Answer: B Explanation: Theme-level RequireJS configuration files belong in the web directory. Question 61. Which of the following is the correct way to retrieve a UI component instance from JavaScript after it has been rendered? A) var component = $('[data-component="myComponent"]').data('uiComponent'); B) var component = uiComponent.get('myComponent'); C) var component = require('uiComponent').get('myComponent'); D) var component = componentRegistry.get('myComponent'); Answer: D Explanation: componentRegistry.get() (or registry.get()) returns the instantiated UI component by name.
