jest for testing describe is not a function - redux

I have made an app using react and redux, I have some components plus their containers and also an action and a reducer.
I am writing a test for one of my containers using enzyme, chai and jest,
when I try to run my test it gives the following error:
Test suite failed to run
TypeError: jest_1.describe is not a function
here is my test file:
import * as React from "react";
import { shallow, mount, render } from 'enzyme';
import * as Sinon from "sinon";
import MinPriceContainer from "../../src/containers/SearchForm/containers/MinPriceContainer";
import MaxPriceContainer from "../../src/containers/SearchForm/containers/MaxPriceContainer";
import { expect } from "chai";
import { it, before, describe } from 'jest';
describe('<MinValueInput />', () => {
let minValueInput;
beforeEach(() => {
minValueInput = shallow(<MinPriceContainer />);
})
// it('renders component correctly', () => {
// expect(tabs.find('.MinPriceComponent').exists()).toBe(true);
// });
it('cannot have a non numeric value', () => {
minValueInput = shallow(<MinPriceContainer minimumPriceSelected="i am a string not a number" />);
expect(minValueInput.find('.error').text()).equal("You cannot use a non numeric value");
});
it('cannot have a value less thn zero', () => {
minValueInput = shallow(<MinPriceContainer minimumPriceSelected={-20} />);
expect(minValueInput.find('.error').text()).equal("value cannot be less than zero");
});
it('it can not have a value greater than maxValue', () => {
minValueInput = shallow(<MinPriceContainer minimumPriceSelected={99} maximumPriceSelected={80}/>);
expect(minValueInput.find('.error').text()).equal("value cannot be greater than price");
});
});
how can I fix this, is this related to my importS?
is the test written correctly?
the component that I am testing has a number value called minPrice and it can not be negative and also it should not be more than another component that is called maxPrice, also it should only accepts numbers!

I take it you're using ts-jest?
replace
import { it, before, describe } from 'jest';
with
import 'jest';

Related

How to test computed value inside setup function in Vue.js 3 with vue-test-utils & Jest

I am getting "TypeError: Cannot add property myData, object is not extensible" on setData
Hello.vue
<template>
<div v-if="isEditable" id="myEditDiv">
<button type="button"> Edit </button>
</div>
</template>
<script lang="ts">
import { computed, defineComponent, reactive} from "vue"
export default defineComponent({
setup() {
const myObject = {myName:"", myNumber:""}
let myData = reactive({myObject})
const isEditable = computed(() => {
return myData.myObject.myName.startsWith('DNU') ? false : true
})
return {
isEditable
}
}
})
</script>
Hello.spec.ts
import { shallowMount } from '#vue/test-utils'
import Hello from '#/components/Hello.vue'
import { reactive } from 'vue'
describe('Hello.vue Test', () => {
it('is isEditable returns FALSE if NAME starts with DNU', async () => {
const myObject = {myName:"DNU Bad Name", myNumber:"12345"}
let myData = reactive({myObject})
const wrapper = shallowMount(Hello)
await wrapper.setData({'myData' : myData})
expect(wrapper.vm.isEditable).toBe(false)
})
})
I also tried to see if that DIV is visible by:
expect(wrapper.find('#myEditDiv').exists()).toBe(false)
still same error. I might be completely off the path, so any help would be appreciated.
Update
This is possible several different ways. There's two issues that need to be addressed.
The variable has to be made available. You can use vue's expose function in setup (but getting the value is really messy: wrapper.__app._container._vnode.component.subTree.component.exposed😱) or just include it in the return object (accessible through wrapper.vm).
change how you mutate the data in the test.
your test has
const myObject = {myName:"DNU Bad Name", myNumber:"12345"}
let myData = reactive({myObject})
const wrapper = shallowMount(Hello)
await wrapper.setData({'myData' : myData})
even if setData was able to override the internal, it would not work.
the problem is that the setup function has this
let myData = reactive({ myObject });
const isEditable = computed(() => {
return myData.myObject.myName.startsWith("DNU") ? false : true;
});
where editable is using a computed generated from that instance of myData. If you override myData with a separate reactive, the computed will still continue to use the old one. You need to replace the contents of the reactive and not the reactive itself
To update the entire content of the reactive, you can use:
Object.assign(myReactive, myNewData)
you can make that a method in your component, or just run that from the test. If you update any value within the reactive (like myData.myObject) you can skip the Object.asign
Here are several versions of how you can test it.
Component:
<template>
<div v-if="isEditable" id="myEditDiv">
<button type="button">Edit</button>
</div>
</template>
<script>
import { computed, defineComponent, reactive } from "vue";
export default defineComponent({
setup(_, { expose }) {
const myObject = { myName: "", myNumber: "" };
let myData = reactive({ myObject });
const isEditable = computed(() => {
return myData.myObject.myName.startsWith("DNU") ? false : true;
});
const updateMyData = (data) => Object.assign(myData, data);
expose({ updateMyData });
return {
isEditable,
updateMyData,
myData
};
},
});
</script>
the test
import { shallowMount } from "#vue/test-utils";
import MyComponent from "#/components/MyComponent.vue";
const data = { myObject: { myName: "DNU Bad Name" } };
describe("MyComponent.vue", () => {
it.only("sanity test", async () => {
const wrapper = shallowMount(MyComponent);
expect(wrapper.vm.isEditable).toBe(true);
});
it.only("myData", async () => {
const wrapper = shallowMount(MyComponent);
Object.assign(wrapper.vm.myData, data);
expect(wrapper.vm.isEditable).toBe(false);
});
it.only("myData", async () => {
const wrapper = shallowMount(MyComponent);
wrapper.vm.myData.myObject = data.myObject;
expect(wrapper.vm.isEditable).toBe(false);
});
it.only("updateMyData method via return", async () => {
const wrapper = shallowMount(MyComponent);
wrapper.vm.updateMyData(data);
expect(wrapper.vm.isEditable).toBe(false);
});
it.only("updateMyData method via expose🙄", async () => {
const wrapper = shallowMount(MyComponent);
wrapper.__app._container._vnode.component.subTree.component.exposed.updateMyData(
data
);
expect(wrapper.vm.isEditable).toBe(false);
});
});
It is not possible through setData
from the docs:
setData
Updates component internal data.
Signature:
setData(data: Record<string, any>): Promise<void>
Details:
setData does not allow setting new properties that are not defined in the component.
Also, notice that setData does not modify composition API setup() data.
It seems that updating internals with composition API is incompatible with setData. See the method name setData, refers to this.data and was likely kept in the vue test utils mostly for backwards compatibility.
I suspect the theory is that it's bad practice anyway to test, what would be considered, an implementation detail and the component test should focus on validating inputs an outputs only. Fundamentally though, this is a technical issue, because the setup function doesn't expose the refs and reactives created in the setup.
There is a MUCH easier way to do this.....
Put your composables in a separate file
Test the composables stand alone.
Here is the vue file:
<template>
<div>
<div>value: {{ counter }}</div>
<div>isEven: {{ isEven }}</div>
<button type="button" #click="increment">Increment</button>
</div>
</template>
<script setup lang='ts'>
import {sampleComposable} from "./sample.composable";
const {isEven, counter, increment} = sampleComposable();
</script>
Here is the composable:
import {computed, ref} from 'vue';
export function sampleComputed() {
const counter = ref(0);
function increment() {
counter.value++;
}
const isEven = computed(() => counter.value % 2 === 0);
return {counter, increment, isEven};
}
Here is the test:
import {sampleComposable} from "./sample.composable";
describe('sample', () => {
it('simple', () => {
const computed = sampleComposable();
expect(computed.counter.value).toEqual(0);
expect(computed.isEven.value).toEqual(true);
computed.increment();
expect(computed.counter.value).toEqual(1);
expect(computed.isEven.value).toEqual(false);
computed.increment();
expect(computed.counter.value).toEqual(2);
expect(computed.isEven.value).toEqual(true);
})
});
This just 'works'. You don't have to deal w/ mounting components or any other stuff, you are JUST TESTING JAVASCRIPT. It's faster and much cleaner. It seems silly to test the template anyway.
One way to make this easier to test is to put all of your dependencies as arguments to the function. For instance, pass in the props so it's easy to just put in dummy values as need. Same for emits.
You can tests watches as well. You just need to flush the promise after setting the value that is being watched:
composable.someWatchedThing.value = 6.5;
await flushPromises();
Here is my flushPromises (which I found here):
export function flushPromises() {
return new Promise(process.nextTick);
}

Vue3 testing ElementPlus controls with vitest

I am running Vue3 with vite and can't write any tests for components that use the ElementPlus library. Something else needs to be injected apparently but I don't know how to do that.
I have the following dateControl.test.js:
import { describe, expect, test } from 'vitest';
import { ref } from 'vue';
import DateCtrl from '#/components/DateCtrl.vue';
import { mount } from "#vue/test-utils";
import ElementPlus from "element-plus";
describe("DateCtrl.vue", () => {
const messages = {
"en-US" : {
strings: {
placeholder: 'a',
label: 'b'
}
}
};
const locale = "en-US";
const data = ref ({
date: ''
});
test ("Arrange DateCtrl", async () => {
const component = mount(DateCtrl, {
props: {
vModel: data.value.date,
modelValue: data.value.date,
labelLoc: "label",
className: "w1x5",
placeholderLoc: "date"
},
global: {
plugins: [ElementPlus],
mocks: {
$t: (msg) => {
const params = msg.split('.');
return messages[locale][params[0]][params[1]];
}
}
}
});
//fails on previous lines.
expect(typeof component !== "undefined", "component created").toBeTruthy();
let h3Text = component.findAll('h3')[0].element.innerHTML;
expect(component.findAll('.form').length === 1, "form element rendered").toBeTruthy();
expect(h3Text === "d", "locale strings correct").toBeTruthy();
});
});
It doesn't even get to the "expect" tests, fails with message:
Error: Cannot find module 'C:\source\mySite\node_modules\dayjs\plugin\customParseFormat'
imported from
C:\source\mySite\node_modules\element-plus\es\components\date-picker\src\date-picker.mjs
Did you mean to import dayjs/plugin/customParseFormat.js?
This bit seems to indicate that node expects you to use .js extension and element is not doing that.
Error: Cannot find module 'C:\source\mySite\node_modules\dayjs\plugin\customParseFormat'
imported from
C:\source\mySite\node_modules\element-plus\es\components\date-picker\src\date-picker.mjs
Did you mean to import dayjs/plugin/customParseFormat.js?
I'm guessing this is because you may be running an older node version. Element requires at least node v16.
I have this problem too.
It seems that this problem is already solved in this pull request - https://github.com/element-plus/element-plus/pull/6811

TypeError: Object(...) is not a function (redux)

I am having a TypeError (TypeError: Object(...) is not a function) when I want to dispatch an action. I'm not using any middleware and don't know what I can do to solve it. I had this error already yesterday but somehow managed to solve it (i donk know how i did this)
This is the App.js:
import React from "react";
import { store } from "../store";
import { withdrawMoney} from "../actions";
const App = () => {
return (
<div className="app">
<div className="card">
<div className="card-header">
Welcome to your bank account
</div>
<div className="card-body">
<h1>Hello, {store.getState().name}!</h1>
<ul className="list-group">
<li className="list-group-item">
<h4>Your total amount:</h4>
{store.getState().balance}
</li>
</ul>
<button className="btn btn-primary card-link" data-amount="5000" onClick={dispatchBtnAction}>Withdraw $5,000</button>
<button className="btn btn-primary card-link" data-amount="10000" onClick={dispatchBtnAction}>Witdhraw $10,000</button>
</div>
</div>
</div>
);
}
function dispatchBtnAction(e) {
store.dispatch(withdrawMoney(e.target.dataset.amount));
}
export default App;
Here is the actioncreator:
function withdrawMoney(amount) {
return {
type: "ADD_TODO",
amount
}
}
If you need here is the reducer:
export default (state, action) => {
console.log(action);
return state
}
As you can see I'm a very new to redux but I'd like to know what mistake I make all the time when dispatching an action. Thanks
I believe the issue is that you aren't exporting the withdrawMoney function, so you aren't able to call it in the component that you're attempting to import into.
try:
export function withdrawMoney(amount) {
return {
type: "ADD_TODO",
amount
}
}
Another subtle mistake that will cause this error is what I tried to do, don't accidentally do this:
import React, { useSelector, useState ... } from 'react'
it should be:
import React, { useState } from 'react'
import { useSelector } from 'react-redux'
Try to install :
npm i react#next react-dom#next and run again
const mapStateToProps = state => ({
Bank: state.Bank,
});
function mapDispatchToProps(dispatch) {
return {
dispatch,
...bindActionCreators({ getBanks, addBank }, dispatch)
}
}
export default connect(
mapStateToProps,
mapDispatchToProps
)(BankComponent);
this worked like a Charm for me .
bit Late to party,
to me it was about casing.
export const addTodo = text => ({
type: ADD_TODO,
desc: text
});
export const removeTodo = id=> ({
type: REMOVE_TODO,
id: id
})
export const increaseCount = () => ({
type: INCREASE_COUNT
});
export const decreaseCount = () => ({
type: DECREASE_COUNT
})
when I renamed all those like
export const AddTodo = text => ({
type: ADD_TODO,
desc: text
});
export const RemoveTodo = id => ({
type: REMOVE_TODO,
id: id
})
export const IncreaseCount = () => ({
type: INCREASE_COUNT
});
export const DecreaseCount = () => ({
type: DECREASE_COUNT
})
it worked.
I spent hours debugging this, turns out I was doing this:
import React, { connect } from "react";
Instead of
import React from "react";
import { connect } from "react-redux";
It's weird the former didn't throw an error, but it will cause the problem!
First problem I see right off the bat is your reducer is not setup to do anything with the dispatched withdrawMoney action creator.
export default (state, action) => {
switch (action.type) {
case "ADD_TODO": {
return {
...state,
amount: action.amount,
};
}
default:
return state;
}
};
If this does not help, the code from your other files would be helpful.
It may not be the main issue, but it looks like you're not using the React-Redux library to work with the store. You can reference the store directly in your React components, but it's a bad practice. See my explanation for why you should be using React-Redux instead of writing "manual" store handling logic.
After updating react-redux to version 7.2.0+ I was receiving this error anytime I wrote:
const dispatch = useDispatch()
I stopped my application and re-ran it with npm start, and everything is working now.
I was using redux toolkit and for me the problem was an extra '}'
such that my 'reducers' object, in 'createSlice' function, already had a closing curly brace before my second reducer
and my 2nd reducer was actually outside the 'reducers' object,
making it not a reducer and hence not working even when you export or import it properly.
So the problem is not in your export or import, but actually where your function is defined.
This may be different for other users, but in my case this turned out to be the cause of this error.

Angular Component Expects 2 Arguments

I'm attempting to create a Wordpress theme compatible with 4.8.x that will render single posts and list of posts as per [this tutorial]:1
When I run the test script, I receive the following errors:
ERROR in C:/MyTheme/src/app/posts/post-list/post-list.component.spec.ts
(9,25): Expected 2 arguments, but got 0.
ERROR in C:/MyTheme/src/app/posts/post-single/post-single.component.spec.ts
(8,25): Expected 2 arguments, but got 0.
The code for both components is very similar and calls into the PostsService which is defined as:
import { Injectable } from '#angular/core';
import { HttpClient } from '#angular/common/http';
import { Post } from './post';
import { environment} from '../../environments/environment';
import {Observable} from 'rxjs/Observable';
#Injectable()
export class PostsService {
private _wpBase = environment.wpBase;
constructor(private http: HttpClient) { }
getPosts():Observable<Post[]> {
return this.http.get<Post[]>(this._wpBase + 'posts');
}
getPost(slug: string): Observable<Post[]> {
return this.http.get<Post[]>(this._wpBase + 'posts?slug=${slug}');
}
}
My post-list-component includes the following:
import { Component, OnInit } from '#angular/core';
import { Post } from '../post';
import { PostsService} from '../posts.service';
import { HttpErrorResponse } from '#angular/common/http';
import {Router} from '#angular/router';
#Component({
selector: 'app-post-list',
templateUrl: './post-list.component.html',
styleUrls: ['./post-list.component.css'],
providers: [PostsService]
})
export class PostListComponent implements OnInit {
posts: Post[];
constructor( private postsService: PostsService, private router: Router ){}
ngOnInit() {
this.postsService.getPosts().subscribe(
(posts: Post[]) => this.posts = posts,
(err: HttpErrorResponse) => err.error instanceof Error ?
console.log('An error has occurred:',
err.error.message):console.log('Backend returned code $(err.status),
body was: ${err.error}'));
}
selectPost(slug) {
this.router.navigate([slug]);
}
}
The error is thrown in the following post.list.component.spec.ts:
/* tslint:disable:no-unused-variable */
import { TestBed, async } from '#angular/core/testing';
import { PostListComponent } from './post-list.component';
import {Router} from "#angular/router";
describe('Component: PostList', () => {
it('should create an instance', () => {
let component = new PostListComponent();
expect(component).toBeTruthy();
});
});
I am not sure how to resolve the errors. It seems to me that PostLisComponent() needs to be passed 2 arguments as per the error, but it's not clear what arguments should be passed. Can anyone assist me in better understanding how to resolve the errors?
its because the constructor use TestBed
import { async, ComponentFixture, TestBed } from '#angular/core/testing';
import { PostListComponent } from './post-list.component';
describe('PostListComponent ', () => {
let component: PostListComponent ;
let fixture: ComponentFixture<PostListComponent >;
beforeEach(async(() => {
TestBed.configureTestingModule({
declarations: [ PostListComponent ]
})
.compileComponents();}));
beforeEach(() => {
fixture = TestBed.createComponent(PostListComponent );
component = fixture.componentInstance;
fixture.detectChanges();
});
it('should create an instance', () => {
expect(component).toBeTruthy();
});
});
From Angular's Testing Guide in regards to the TestBed, and why it would fit such a scenario:
TestBed is the first and most important of the Angular testing
utilities ... In effect, you detach the tested component from its own
application module and re-attach it to a dynamically-constructed
Angular test module tailored specifically for this battery of tests.
Right now, you're statically constructing instead of dynamically constructing using the TestBed, which is causing the error since the constructor of the PostListComponent contains two parameters which would be required to be filled in case of static constructing.

Updating a template with a component input

Preface: I'm new to Meteor, Angular, and Typescript, so there is a very real possibility of an XY problem somewhere in here.
I'm working on a simple project management app using Meteor and Angular 2 (using the angular2-meteor package) where the structure (for now) consists of projects which have events. One view is a list of projects. Clicking on a project shows a modal of the project's details, including a list of the project's events. So, three components: ProjectList, ProjectDetails, and ProjectEventsList. ProjectDetails uses a Session variable to know which project to show, and that works. However, the list of events in the modal doesn't update after it is created for the first project clicked on.
ProjectEventsList.ts
import {Component, View} from 'angular2/core';
import {MeteorComponent} from 'angular2-meteor';
import {ProjectEvents} from 'collections/ProjectEvents';
#Component({
selector: 'projectEventsList',
inputs: ['projectId']
})
#View({
templateUrl: '/client/projectEventsList/projectEventsList.html'
})
export class ProjectEventsList extends MeteorComponent {
projectEvents: Mongo.Cursor<ProjectEvent>;
projectId: string;
constructor() {
super();
this.subscribe('projectEvents', this.projectId, () => {
this.autorun(() => {
this.projectEvents = ProjectEvents.find({projectId: this.projectId});
}, true);
});
}
}
As I understand it (though I may be way off here), I'm having difficulty getting autorun to, well, automatically run. I've tried putting a getter and setter on projectId and it does get updated when I click on a project, but the code inside autorun doesn't run after the first click. Things I've tried:
Switching the nesting of subscribe() and autorun().
Adding/removing the autobind argument to both subscribe() and autorun(). I don't really understand what that's supposed to be doing.
Moving the subscribe code to a setter on projectId:
private _projectId: string = '';
get projectId() {
return this._projectId;
}
set projectId(id: string) {
this._projectId = id;
this.subscribe('projectEvents', this._projectId, () => {
this.projectEvents = ProjectEvents.find({projectId: this._projectId});
}, true);
}
When I do this the list stops displaying any items.
If this all seems like it should work, I'll create a small test case to post, but I am hoping that something in here will be obviously wrong to those who know. Thanks!
this.subscribe() and this.autorun() doesn't seem to be part of the Angular component class. If this is an external library you might need to explicitly run it in an Angular zone for change detection to work:
constructor(private zone: NgZone) {
this.subscribe('projectEvents', this.projectId, () => {
this.autorun(() => {
zone.run(() => {
this.projectEvents = ProjectEvents.find({projectId: this.projectId});
});
}, true);
});
}
If you want to subscribe to events fired from the component itself use host-binding
#Component(
{selector: 'some-selector',
host: {'projectEvents': 'projectsEventHandler($event)'}
export class SomeComponent {
projectsEventHandler(event) {
// do something
}
}
I eventually got the setter method working, as shown below. It feels clunky, so I'm hoping there's a cleaner way to do this, but the below is working for me now (i.e., the list of events is updated when the parent component (ProjectList) sends a new projectId to the input.
ProjectEventsList.ts
import {Component, View} from 'angular2/core';
import {MeteorComponent} from 'angular2-meteor';
import {ProjectEvents} from 'collections/ProjectEvents';
#Component({
selector: 'projectEventsList',
inputs: ['projectId']
})
#View({
templateUrl: '/client/projectEventsList/projectEventsList.html'
})
export class ProjectEventsList extends MeteorComponent {
projectEvents: Mongo.Cursor<ProjectEvent>;
set projectId(id: string) {
this._projectId = id;
this.projectEventsSub = this.subscribe('projectEvents', this._projectId, () => {
this.projectEvents = ProjectEvents.find({projectId: this._projectId}, {sort: { startDate: 1 }});
}, true);
}
get projectId() {
return this._projectId;
}
constructor() {
super();
this.subscribe('projectEvents', this.projectId, () => {
this.projectEvents = ProjectEvents.find({projectId: this.projectId});
}, true);
}
}

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