Vue test utils set data. It ran fine in VTU v.

Vue test utils set data. This guide covers best practices, setup, and practical examples for robust component testing. This guide will cover how to: Mount components Find elements Fill out forms Trigger events Getting Started We will start off with a simple TodoApp component with a single todo: You’re browsing the documentation for Vue Test Utils for Vue v2. Testing v-model When writing components that rely on v-model interaction (update:modelValue event), you need to handle the event and props. source There is probably Reusability & Composition Mostly: global. This library provides tools for mounting components, interacting with their rendered output, and verifying their behavior through assertions. Vue Test Utils (VTU) is a set of utility functions aimed to simplify testing Vue. Form Handling Forms in Vue can be as simple as plain HTML forms to complicated nested trees of custom Vue component form elements. Oct 16, 2021 · I use typescript and vue-class-component on vue3. A single test case would assert May 11, 2025 · Mount Options Relevant source files This page documents the configuration options that can be passed to the mount and shallowMount functions in Vue Test Utils. 3 with jest@26 in order to test my component. It accepts a parameter, most often a String or a Boolean, and returns a Promise, which resolves after Vue has updated the DOM. It returns an object with all the events the component has emitted, and their arguments in an array. Real-World Example Unit tests should be: Fast to run Easy to understand Only test a single unit of work Plugins Plugins add global-level functionality to Vue Test Utils' API. Stubbing a single child component A common example is when you would like to May 11, 2025 · Vue Test Utils (VTU) is the official testing library for Vue. Example: Apr 20, 2019 · I'm using vue-test-utils with jest, I have router-link being rendered in a Login Component. It is built on top of @vue/test-utils, the official testing library for Vue. Thus, Vue Test Utils doesn't feature any unique tool to do so. For setup, I'd generally just recommend interacting with the component via trigger or passing props to test it (like a user would). setData({ hovered: true }); Which results in this error: TypeError: Cannot add property hovered, object is not extensible Component looks like (simplified): import { Vue } from 'vue-class-component'; export default class Test extends Vue { hovered = false; } You’re browsing the documentation for Vue Test Utils for Vue v2. vue before triggering the submit, my test will pass. Jul 13, 2020 · Often we need to design a custom component which needs to communicate data with its parent. Real-World Example Unit tests should be: Fast to run Easy to understand Only test a single unit of work Sep 18, 2017 · The methods that vue-test-utils give us, such as emitted or setData, take care of that under the hood. This page covers the wrapper object interfaces, hierarchy, and May 5, 2025 · Testing is vital for the reliability of our applications. directives. Feb 5, 2016 · What is actually happening? setData doesn't update correctly the data and console print "Cannot read property 'split' of undefined", seems wrapper is not mounted, if i remove data from App. Arguments: {Object} data Exemple: Vue Test Utils (VTU) is a set of utility functions aimed to simplify testing Vue. It covers testing default slots, named slots, and scoped slots, as well as advanced patterns for providing slot content during testing. It sets data only in wrapper. setData({ name: 'New File' }) But I cannot do this, because formWrapper is an HTMLElement not a Vue Instance. js DevelopersResources Vue Test Utils Our objective in this module is to learn how to unit test a Vue. 6k. However, there's only so much VTU can do. As you can see, setValue sets the value property on the input element to what we pass to it. Here are a bunch of Vue-Test-Utils tips, tricks and features that you may or may not be aware of. Overview of Mount Options The Apr 6, 2018 · edited @eddyerburgh version: @vue/test-utils": "^1. A hands-on guide to improving your testing skills. Let's see an example: Utilities for testing Vue componentsYou’re browsing the documentation for Vue Test Utils for Vue v2. Aug 3, 2024 · Vue Test Utils is a set of utility functions aimed to simplify testing Vue. plugins Mar 3, 2025 · Learn how to write effective unit tests for Vue. The problem with the above code is that I have started getting the following warning when the tests run: setdata is a method provided by Vue Test Utils that allows you to set data on a component instance. For information on the core mounting API itself, see Core Mounting API. A Simple Example You might have a generic <layout> component that uses a default slot to render some content. It serves as the primary interface through which you access component properties, trigger events, locate elements, and assert component behavior. If you set the data property on the VM property directly with wrapper. js community collaborate to maintain up-to-date guides and resources, ensuring a seamless integration process for developers. Here's how you can get started testing Vue components in Node with Vue Test Utils. The answer looks like there is no solution What I got from this thread is that: setData only works with data. Also, you can find different test cases of Vue components in the GitHub repository. Getting started Vue Test Utils is the official library for unit testing Vue components. E. vue SFC error changes and it is "Avoid adding reactive properties to a Vue instance or its root $data at runtime - declare it upfront in the data option. The component gets its data via a dependency provider. The following list provide general guidance and it might come in handy in common scenarios. option. js Jest integrates smoothly with Vue. Let's see an example. However, it is an important feature to test, and there are a few gotchas we want to highlight. Apr 18, 2021 · wrapper. The component gets provide data from a parent, and watches for changes of it. vue <template> <d Nov 9, 2022 · When testing a component that calls setData with a non-primitive class/object, the object gets set into the component VM without the prototype properties which breaks what should be a straightforward test. The mount method is used to create an instance of the component in a virtual DOM. Learn how to create unit tests with vue-test-utils and Vuetify components in your Vue application. I think that what the Vue and the Test-Utils/Vue team need to coordinate on is documenting exactly how to upgrade tests based on the Options API to the composition API. 1. If you are new to testing Vue applications, we would recommend using Vue Testing Library, which is an abstraction over Vue Test Utils. May 31, 2023 · According to the documentation, Vue Test Utils (VTU) is a set of helper functions designed to simplify testing Vue. Rich Feature Set: Vitest includes features like snapshot testing, mocking, and watch mode for streamlined development. recordType on an element with the attribute data-test-id="record-type-error" this fails Mar 20, 2018 · vuejs / vue-test-utils Public Notifications You must be signed in to change notification settings Fork 665 Star 3. Note - le Wrapper doit contenir une instance de Vue. setData doesn't set data in component. Jun 16, 2021 · I'm using vue-test-utils@1. x and earlier. This library provides a method for mounting Vue components and interacting with them in an isolated manner. There is data called 'email', on its update forgot link get's Oct 28, 2024 · In this article, we will explore how to test the use of a composable within a Vue 3 component with Jest and Vue Test Utils—the concepts, however, are directly translatable to Vitest. These methods can be referred to as a wrapper. setProps () 来动态更新组件接收的 props。 Oct 22, 2020 · That's the main thing - without a clear way to access (read & set) what's returned from setup () in the test suite, it's going to be hard to test things going forward. In this section, we explore the data and props mounting options, as well as VueWrapper. What is Vue Test Utils? Vue Test Utils (VTU) is a set of utility functions aimed to simplify testing Vue. So let's go to the top of the file and put import { mount } from "@vue/test-utils";. I'm trying to test a little logic inside the setter of a computed property by calling "wrapper. Feb 6, 2023 · vue/test-utils - or Vue Test Utils is the official testing library for the Vue component. js components. A Crash Course Let's jump right into it! Let's learn Vue Test Utils (VTU) by building a simple Todo app and writing tests as we go. A Simple Example Here a simple Editor component: May 31, 2023 · In this article, we will explore the usage of Vue Test Utils (VTU), the official unit testing utility library for Vue. A Simple Example Here is a simple component that combines props and data to render a greeting: For inexperienced testers, Vue. We'll need to first mount our component using Vue Test Utils. A Wrapper is an object that contains a mounted component or vnode and methods to test the component or vnode. Mounting Options context data slots scopedSlots stubs mocks localVue attachTo attachToDocument attrs propsData listeners parentComponent provide Other options context type: Object Passes context to functional component. The official API reference for Vue Test Utils, a utility suite for testing Vue. Aug 8, 2025 · Learn how to create unit tests with vue-test-utils and Vuetify components in your Vue application. js components using Jest and Vue Test Utils. js 3 components. Mar 2, 2025 · Learn how to effectively test Vue. trigger('input'), v-model is not triggered. To read docs for Vue Test Utils for Vue 3, click here. Vue Testing Library on GitHub In short, Vue Testing Library does three things: Re-exports query utilities and helpers from DOM Testing Library. Read this article on Vue Test Utils to learn how to use them to write and run tests on Vue app components. May 15, 2025 · Testing Components with Slots Relevant source files Purpose and Scope This document explains how to use Vue Test Utils (VTU) to test components that utilize Vue's slot system for content distribution. You can access that with the vm property. Apr 18, 2021 · If you are expecting to set the value of ref declared in setup, this will not work - setData only works with data. 在本节中，我们将探讨 data 和 props 挂载选项，以及 VueWrapper. Something like this:- let formWrapper = appWrapper. mixins. I'm wondering if th You’re browsing the documentation for Vue Test Utils for Vue v2. Note the Wrapper must contain a Vue instance. May 17, 2020 · Vue has an excellent testing package called vue-test-utils. Nowadays, it’s better to just migrate to … Component Instance mount returns a VueWrapper with lots of convenient methods for testing Vue components. May 11, 2025 · Wrapper API Relevant source files The Wrapper API is a core component of Vue Test Utils that provides methods to interact with mounted Vue components and DOM elements during testing. For this purpose, let us implement the below user interface which consists of a label Vuetify component reflecting what is being 测试 Vue 组件的实用工具You’re browsing the documentation for Vue Test Utils for Vue v2. set or vm. This can be useful for testing the behavior of a component when it is in a particular state. foo = bar it works as Apr 15, 2020 · javascript unit-testing vue. element. To fully test this component, we should verify that an increment event with the latest count value is emitted. setData works by recursively calling Vue. js jestjs vue-test-utils edited Apr 15, 2020 at 8:13 skyboyer 24k 7 64 72 Jul 24, 2018 · Testing Vue components: a cheat sheet March 2019 edit: A lot of this article deals with integrating jest and vue-test-utils into an existing Vue app. This is the official way to extend Vue Test Utils' API with custom logic, methods, or functionality. I can grab a data property by using something like wrapper. js. Vue. g. Interacting with form elements Let's take a look at a very basic form: Feb 28, 2019 · How can I access a data property in a Vue test instance? I see that you can access props, but there's no data equivalent. js, thanks to the Vue Test Utils library which provides easy ways to mount and interact with Vue components within tests. To use setdata, you simply pass the component instance and the data that you want to set as arguments. 0-beta. 1, but it doesn't seem to call the setter at all in v. If you prefer to use @vue/test-utils on its own for unit testing in Nuxt, and you are only testing components which do not rely on Nuxt composables, auto-imports or context, you can follow these steps to set it up. It's also the lower-level library @testing-library/vue is built on top of. You can read more about asynchronous updates in the Vue docs In Slots Vue Test Utils provides some useful features for testing components using slots. I created a simple components: Oct 24, 2020 · I am new in Vue and I am already heading this issue. Contribute to vuejs/test-utils development by creating an account on GitHub. " Getting started Vue Test Utils is the official library for unit testing Vue components. I'm passing router to the component as well. The aim of this article is to show how to test emit event using Vue Test Utils and Jest. setSelected() is an alias of the following code. setData (data) WrapperArray の Wrapper ごとに Wrapper に vm データをセットします。 すべての Wrapper は Vue インスタンスを含んでいなければならないことに注意してください。 引数: {Object} data 例: Feb 12, 2025 · If the array is empty it shows a "no data" message. Run the command below to test the component in watch mode: npm run test Jun 19, 2024 · Compatibility of Jest with Vue. js 3, designed to facilitate the testing of Vue components in isolation. Do not test implementation If you have other properties in data, don't worry - Vue Test Utils will merge the two together. setData ( { selectedValue: ["Work","Home"] }). This allow us to test the component without the hassle of compiling the whole app in a browser. global. Sep 14, 2020 · Vue Test Utils is Vue's official unit testing library for Node. find('file-form') formWrapper. It is easy to pick up and nice to test with. Some use cases for plugins: Aliasing existing public methods Attaching matchers to the Wrapper instance Attaching functionality to the Wrapper Wrapper Plugin Using a Plugin Install plugins by calling the config. Can only be used with functional components . The Jest community and Vue. 16" I have a v-if pointing to a data property called errors. Setting element values The most common way to bind an input to data in Vue is by using v-model. A stub is where you replace an existing implementation of a custom component or directive with a dummy one that doesn't do anything at all, which can simplify an otherwise complex test. Parent component injects a computed value. But Vitest and Vue Test Utils makes testing Vue components a breeze! Testing Asynchronous Behavior There are two types of asynchronous behavior you will encounter in your tests: Updates applied by Vue Asynchronous behavior outside of Vue Updates applied by Vue Vue batches pending DOM updates and applies them asynchronously to prevent unnecessary re-renders caused by multiple data mutations. Dec 17, 2020 · Subject of the issue When you have a watcher on a data property that is an Object, and you use setData to override the Object, it does not trigger the watcher, but the data is updated. But so far, we've only seen how to test a regular JavaScript function. with testing-library/vue If the first option is too hard to do, try to come up with some fake testing component. Stubs and Shallow Mount Vue Test Utils provides some advanced features for stubbing components and directives. setProps() to dynamically update the props a component receives. Vue Test Utils provides several ways to set data and props on a component, to allow you to fully test the component's behavior in different scenarios. setData Définis les données Wrapper vm. Using vitest and test-utils I am trying to write a test which ensures the "no data" message is rendered if the provided array is empty and renders the data if the array is populated. Utilities for testing Vue componentsYou’re browsing the documentation for Vue Test Utils for Vue v2. Let's see how it works: Aug 9, 2022 · Intro Vue Testing Library builds on top of DOM Testing Library by adding APIs for working with Vue components. See the essentials of testing Vue applications using Vitest and @vue/test-utils. Sometimes you might want access to the underlying Vue instance. Let's start with a simple example: Jan 19, 2022 · I created a component using the setup in vue3, how can I update vue ref using vue-test-util 2? @vue/test-utils is the official low-level component testing library that was written to provide users access to Vue specific APIs. With this shift towards front-end heavy JavaScript web apps, testing practices are more important than ever. 0. These functions render Vue components in isolation, enabling precise testing of component behavior. In this section, we explore some patterns to perform, mock, and assert HTTP requests. So the last test can be written in a cleaner way just by using setData: Jul 23, 2021 · This guide showcases the benefits of testing your Vue. The data in the mounting options will take priority over any default values. As you probably know by now, it takes care of what events each form element emits, and the props it accepts, making it easy for us to work with form elements. Following is a list of suggestions to write code that is easier to test, and to write tests that are meaningful and simple to maintain. vm object. These options allow you to customize how components are mounted for testing, including providing props, slots, attributes, and more. js components using Vue Test Utils and includes some real-world examples. If you have not yet started testing your Vue applications then I recommend that you check out Vue Test Utils. Steps to reproduce WatcherNotFired. setData({ showNextButton: true }); // TypeError: Cannot add property sh Sep 19, 2019 · How to find input and simulate change value in vue-test-utils with jest, the best practices Asked 5 years, 11 months ago Modified 4 years, 6 months ago Viewed 16k times Making HTTP requests Modern test runners already provide lots of great features when it comes to test HTTP requests. You should import { expect, test } from "vitest"; if you set the value of globals to false in the Vite configuration file. Instead, we recommend writing tests that assert your component's public interface, and treat its internals as a black box. setData fonctionne en appelant récursivement Vue. For information about interacting with ¥Vue Test Utils provides several ways to set data and props on a component, to allow you to fully test the component's behavior in different scenarios. It would be very similar to Vue. vm. foo, but I f Jun 12, 2019 · Try to test it manually first, notice how do you do it, then try to write a similar test. Mar 3, 2018 · In this example, I want to set the pageSize value before the life cycle mounted is called. To change the value of an input in VTU, you can use the setValue() method. Feb 13, 2018 · Edd Yerburgh, a core Vue team member and the maintainer of vue-test-utils (formerly Avoriaz), defines automated testing in his book as: Automated testing is the practice of writing programs to run tests against your application code. It accepts a parameter, most often a String or a Boolean, and Utilities for testing Vue componentsYou’re browsing the documentation for Vue Test Utils for Vue v2. selected = true; parentSelect. It ran fine in VTU v. A list of blog posts Let's start May 11, 2025 · Core Mounting API Relevant source files The Core Mounting API provides the primary entry points for testing Vue components with Vue Test Utils. We will gradually go through the ways of interacting with form elements, setting values and triggering events. Asserting the emitted events To do so, we will rely on the emitted() method. There isn't a good way to modify a value inside a function (like setup). $set but be more consistent with how data is currently set in tests. when I want to change the component data I will get an error: await wrapper. Check VueJS VModel event documentation. v-model is triggered by change event. A single test case would assert Wrapper Vue Test Utils is a wrapper based API. Testing composables When working with the composition API and creating composables, you often want to test only the composable. Apr 27, 2018 · The proposed API adds a setDataObj method to vue-test-utils thereby allowing you to set data if updating an object rather than a value. js app. 2. For example: Jan 13, 2025 · Vue Integration: It works well with Vue Test Utils, the official testing library for Vue. May 20, 2021 · I'm trying to unit test a simple method in Vue 2 logNumberInSet (index, inputsLength) { this. Utilities for testing Vue componentsNote: When you try to set the value to state via v-model by option. It provides some methods to mount and interact with Vue components in an isolated manner. js applications. May 5, 2021 · I'm doing this inside a test: await wrapper. I We read every piece of feedback, and take your input very seriously Dec 4, 2024 · As Vue has continued to explode in popularity as a front-end framework over the past few years, more and more web applications are being built using single-file Vue components. It provides a set of utility functions for simplifying testing Vue components. An important to understand that, in a component-based app, a "unit" is generally not a single function, but is instead a whole component. So, how do we unit test a component? At a high level it's the same Apr 11, 2025 · This step-by-step tutorial teaches how to use Jest Vue Test Utils with Vue3. Studies have shown: Unit testing reduces up to 40% of […] If you have other properties in data, don't worry - Vue Test Utils will merge the two together. Vue Test Utils for Vue 3. Write components that are easy to test Vue Test Utils helps you write tests for Vue components. js testing can be intimidating. Check "vmodel integration" Discussion for some community solutions. set. This page documents the mount() and shallowMount() functions, which are the foundation of Vue component testing. Mar 3, 2018 · If somehow I can set the data, which in this case the name property of the FileForm. One way to achieve this is to rely on the emit event through the v-model directive. The vue-cli webpack template comes with either Karma or Jest, both well supported test runners, and there are some guides in the Vue Test Utils documentation. The methods we will be using the most are setValue() and trigger(). Common Tips Knowing What to Test For UI components, we don't recommend aiming for complete line-based coverage, because it leads to too much focus on the internal implementation details of the components and could result in brittle tests. numberInASet[index] = inputsLength + 1; }, data () { return Vue Test Utils provides several ways to set data and props on a component, to allow you to fully test the component's behavior in different scenarios. For related testing techniques, see Testing with Stubs and Apr 19, 2023 · We import mount from @vue/test-utils, allowing us to wrap our component into a special object called Wrapper, which gives us various test options. Vue Test Utils is the official low-level component testing library that was written to provide users access to Vue specific APIs. In essence, a wrapper is an abstraction of the mounted component. o3zy mwd1v3rr qcm fbk owm msmq mccu ezx6 jlhlo gm3m5