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How to use checkIsError method in Jest

Best JavaScript code snippet using jest

index.js

Source:index.js

...206                                                                }207                                                            </div>208                                                            <TextField209                                                                error={210                                                                    checkIsError(errors, touched, index, true)211                                                                }212                                                                variant="standard"213                                                                margin="dense"214                                                                fullWidth215                                                                onChange={handleChange}216                                                                value={actor.name}217                                                                id={`actors.${index}.name`}218                                                                label="Name"219                                                                name={`actors.${index}.name`}220                                                                helperText={221                                                                    checkIsError(errors, touched, index, true)222                                                                }223                                                                required224                                                                color='secondary'225                                                            />226                                                            <TextField227                                                                error={228                                                                    checkIsError(errors, touched, index)229                                                                }230                                                                variant="standard"231                                                                margin="dense"232                                                                fullWidth233                                                                onChange={handleChange}234                                                                value={actor.surname}235                                                                id={`actors.${index}.surname`}236                                                                label="Surname"237                                                                name={`actors.${index}.surname`}238                                                                helperText={239                                                                    checkIsError(errors, touched, index)240                                                                }241                                                                required242                                                                color='secondary'243                                                            />244                                                        </div>245                                                    ))246                                                }247                                                <span className={classes.plusContainer}>248                                                    <AddCircle className={classes.plusIcon} onClick={() => push({ name: '', surname: '' })} />249                                                </span>250                                            </div>251                                        )}252                                    </FieldArray>253                                    <p className={classes.error}>{error}</p>...

script.js

Source:script.js

1//Function for adding author via fetch request2$('#add_author').on('submit', async function (e) {3    e.preventDefault()4    const res = await requestToBackend($(this).attr('action'), 'POST', new FormData(this))5    if (!checkIsError(res)) {6        alertShow($('#successAlert'))7        $('.body').append(createAuthorCard(res.data))8    }9})10//Function for adding a book through a fetch request11$('#add_book').on('submit', async function (e) {12    e.preventDefault()13//Create an array for storing author IDs and put data from the form into it14    let authorsId = createAuthorIdArray($("span[name='author']"))15//Create form data variables16    let data = new FormData(this)17    data.append('authorsId', authorsId)18    console.log(data.image)19    const res = await requestToBackend($(this).attr('action'), 'POST', data)20    if(!checkIsError(res)) {21        alertShow($('#successAlert'))22        showBookCard(res.data)23    }24})25//Function to open the author edit window26$("[name='authorForm']").on('submit', function (e) {27    e.preventDefault()28    let authorNameBox = $(this).children(".authorName")29    $("input[name='authorId']").val(authorNameBox.children("input[name='id']").val())30    $("input[name='lastname']").val(authorNameBox.children("p[name='lastname']").text())31    $("input[name='name']").val(authorNameBox.children("p[name='name']").text())32    $("input[name='patronymic']").val(authorNameBox.children("p[name='patronymic']").text())33})34//Function for sending a request to edit an author35$('#edit_author').on('submit',async function (e) {36    e.preventDefault()37    const res = await requestToBackend($(this).attr('action'), 'PATCH', new FormData(this))38    if (!checkIsError(res)) {39        alertShow($('.alert-success'))40        editAuthorCard(res.data)41    }42})43//Function for sending a request to delete an author44async function deleteAuthor(btn) {45    const res = await requestToBackend($(btn).data('link'), 'DELETE')46    if(!checkIsError(res)) {47        alert('ÐÐ²ÑÐ¾Ñ ÑÐ´Ð°Ð»ÐµÐ½')48        $('.author-' + res.data).remove()49    }50}51//Function of sending a request to delete a book52async function deleteBook(btn) {53    const res = await requestToBackend($(btn).data('link'), 'DELETE')54    const book = res.data55    if(!checkIsError(res)) {56        alert('ÐÐ½Ð¸Ð³Ð° ' + book.title + 'ÑÐ´Ð°Ð»ÐµÐ½Ð°' )57        $(`#book-${book.title}`).remove()58    }59}60//Function for sorting authors/books61//The function takes the pressed button as a parameter62async function sort(btn) {63    const res = await requestToBackend($(btn).data('url'), 'GET')64    if (!checkIsError(res)) {65        refreshList(res.data, $(btn).data('flag'))66    }67}68//Search function for authors/books69async function search(btn) {70//Create variable request addresses71    let url = $(btn).data('url') + $('#search').val()72    const res = await requestToBackend(url, 'GET')73    if (!checkIsError(res)) {74        refreshList(res.data, $(btn).data('flag'))75    }76}77//Function on / off the search button depending on the presence of text in the search input field78$('#search').on('input', function () {79    if($(this).val()){80        $('#searchBtn').removeAttr('disabled')81    }else{82        $('#searchBtn').attr('disabled', 'disabled')83    }84})85//The function of adding an author to the list of authors when creating a new book86function addToList(select){87    let authorName = select.options[select.selectedIndex].text88    $('#authorsList').append($('<span>', {89        class: 'badge badge-light',90        text: authorName,91        value: select.value,92        name: 'author'93    }))94}95//Author card creation function96function createAuthorCard(author) {97    return $("<div class=\"card w-100 author-" + author._id + "\">\n" +98        "<div class=\"card-body\">\n" +99            "<form name=\"authorForm\">\n" +100                "<div class=\"authorCard authorName author-" + author._id + "\">\n" +101                    "<p class=\"name\" id=\"lastname\" onformdata=\"lastname\">" + author.lastname + "</p>\n" +102                    "<p class=\"name\" id=\"name\">" + author.name + "</p>\n" +103                    "<p class=\"name\" id=\"patronymic\">" + author.patronymic +"</p>\n" +104                    "<input class=\"name\" name=\"id\" readOnly type=\"hidden\" value=\"" + author._id + "\">\n" +105                "</div>\n" +106                "<div class=\"btn-group btn-card authorCard\">\n" +107                    "<button type=\"submit\" class=\"btn btn-info\" data-toggle=\"modal\" data-target=\"#editModalWindow\">\n" +108                        "Edit\n" +109                    "</button>\n" +110                    "<button type=\"button\" class=\"btn btn-danger\" onClick=\"deleteAuthor(this)\" data-link=\"/api/authors/"+ author._id +"\">\n" +111                        "Delete\n" +112                    "</button>\n" +113                "</div>\n" +114            "</form>\n" +115        "</div>\n" +116    "</div>")117}118//Book card creation function119function createBookCard(book) {120    return $(121        "<div id=\"book-"+ book.title +"\" class=\"card mb-8\" style=\"max-width: 740px;\">\n" +122            "<div class=\"row g-0\">\n" +123                "<div class=\"col-md-2\">\n" +124                    "<img class=\"book-img\" src=\"/uploads/" + book.image + "\">\n" +125                "</div>\n" +126                "<div class=\"col-md-8\">\n" +127                    "<div class=\"card-body " + book.title + "\">\n" +128                        "<h5 class=\"card-title\">" + book.title + "</h5>\n" +129                        "<p class=\"card-text\">" + book.description + "</p>\n" +130                        "<label>ÐÐ²ÑÐ¾ÑÑ</label>\n" +131                    "</div>\n" +132                "</div>\n" +133                "<div class=\"col-md-2\">\n" +134                    "<div class=\"card-body\">\n" +135                        "<div class=\"btn-group btn-card\">\n" +136                            "<button type=\"button\" class=\"btn btn-danger\" onclick=\"deleteBook(this)\" data-link=\"/api/books/"+ book._id +"\">\n" +137                                "Delete\n" +138                            "</button>\n" +139                        "</div>\n" +140                    "</div>\n" +141                "</div>\n" +142            "</div>\n" +143        "</div>\n")144}145//The function of displaying authors in the book card when adding a new book146function showAuthor(authors, title) {147     return authors.forEach( (author) => {148        let authorName = '' + author.name + ' ' + author.lastname + ' ' + author.patronymic149        $(`.${title}`).append($('<span>', {150            class: 'badge badge-light',151            text: authorName152        }))153    })154}155//Author card editing function156function editAuthorCard(author) {157    $(`.author-${author._id}`).children("p[name='lastname']").text(author.lastname)158    $(`.author-${author._id}`).children("p[name='name']").text(author.name)159    $(`.author-${author._id}`).children("p[name='patronymic']").text(author.patronymic)160}161//function of updating the list of authors / books162function refreshList(array, flag) {163    164    switch (flag) {165        case 'authors' :166            $('.card').remove()167            array.forEach((author) => {168                $('.body').append(createAuthorCard(author))169            })170            break171        case 'books' :172            $('.card').remove()173            array.forEach((book) => {174                $('.body').append(createBookCard(book))175                $('.authors').append(showAuthor(book.authors, book.title))176            })177            break178    }179}180//Info message display function181function alertShow(alert) {182        alert.css('display', 'block')183        setTimeout(function(){184            alert.css('display', 'none')185        }, 3000)186}187//Function to create an array of author IDs188function createAuthorIdArray(span) {189    const authorsId = []190    span.each(function (index){191        authorsId.push($(this).attr('value'))192    })193    return authorsId194}195//The function of creating a book card196//when a response from the server about the successful addition of a book to the database197function showBookCard(book) {198    $('.body').append(createBookCard(book))199    $('.authors').append(showAuthor(book.authors, book.title))200}201//Function for request to backend202async function requestToBackend(url, method, body = null) {203    const res = {}204    await fetch(url, {205        method: method,206        body: body207    })208        .then(response => response.json())209        .then(data => res.data = data)210        .catch(e => res.e = e)211    return res212}213//Function checking for an error in response214function checkIsError(res) {215    if (res.e) {216        console.log(e)217        alertShow($('#errorAlert'))218        return true219    }...

jasmineAsyncInstall.js

Source:jasmineAsyncInstall.js

1'use strict';2Object.defineProperty(exports, '__esModule', {3  value: true4});5exports.default = jasmineAsyncInstall;6var _co = _interopRequireDefault(require('co'));7var _isGeneratorFn = _interopRequireDefault(require('is-generator-fn'));8var _throat = _interopRequireDefault(require('throat'));9var _isError3 = _interopRequireDefault(require('./isError'));10function _interopRequireDefault(obj) {11  return obj && obj.__esModule ? obj : {default: obj};12}13var Symbol = global['jest-symbol-do-not-touch'] || global.Symbol;14var Symbol = global['jest-symbol-do-not-touch'] || global.Symbol;15var Promise = global[Symbol.for('jest-native-promise')] || global.Promise;16function isPromise(obj) {17  return obj && typeof obj.then === 'function';18}19function promisifyLifeCycleFunction(originalFn, env) {20  return function(fn, timeout) {21    if (!fn) {22      return originalFn.call(env);23    }24    const hasDoneCallback = typeof fn === 'function' && fn.length > 0;25    if (hasDoneCallback) {26      // Jasmine will handle it27      return originalFn.call(env, fn, timeout);28    }29    const extraError = new Error(); // Without this line v8 stores references to all closures30    // in the stack in the Error object. This line stringifies the stack31    // property to allow garbage-collecting objects on the stack32    // https://crbug.com/v8/714233    extraError.stack = extraError.stack; // We make *all* functions async and run `done` right away if they34    // didn't return a promise.35    const asyncJestLifecycle = function asyncJestLifecycle(done) {36      const wrappedFn = (0, _isGeneratorFn.default)(fn)37        ? _co.default.wrap(fn)38        : fn;39      const returnValue = wrappedFn.call({});40      if (isPromise(returnValue)) {41        returnValue.then(done.bind(null, null), error => {42          const _isError = (0, _isError3.default)(error),43            checkIsError = _isError.isError,44            message = _isError.message;45          if (message) {46            extraError.message = message;47          }48          done.fail(checkIsError ? error : extraError);49        });50      } else {51        done();52      }53    };54    return originalFn.call(env, asyncJestLifecycle, timeout);55  };56} // Similar to promisifyLifeCycleFunction but throws an error57// when the return value is neither a Promise nor `undefined`58function promisifyIt(originalFn, env, jasmine) {59  return function(specName, fn, timeout) {60    if (!fn) {61      const spec = originalFn.call(env, specName);62      spec.pend('not implemented');63      return spec;64    }65    const hasDoneCallback = fn.length > 0;66    if (hasDoneCallback) {67      return originalFn.call(env, specName, fn, timeout);68    }69    const extraError = new Error(); // Without this line v8 stores references to all closures70    // in the stack in the Error object. This line stringifies the stack71    // property to allow garbage-collecting objects on the stack72    // https://crbug.com/v8/714273    extraError.stack = extraError.stack;74    const asyncJestTest = function asyncJestTest(done) {75      const wrappedFn = (0, _isGeneratorFn.default)(fn)76        ? _co.default.wrap(fn)77        : fn;78      const returnValue = wrappedFn.call({});79      if (isPromise(returnValue)) {80        returnValue.then(done.bind(null, null), error => {81          const _isError2 = (0, _isError3.default)(error),82            checkIsError = _isError2.isError,83            message = _isError2.message;84          if (message) {85            extraError.message = message;86          }87          if (jasmine.Spec.isPendingSpecException(error)) {88            env.pending(message);89            done();90          } else {91            done.fail(checkIsError ? error : extraError);92          }93        });94      } else if (returnValue === undefined) {95        done();96      } else {97        done.fail(98          new Error(99            'Jest: `it` and `test` must return either a Promise or undefined.'100          )101        );102      }103    };104    return originalFn.call(env, specName, asyncJestTest, timeout);105  };106}107function makeConcurrent(originalFn, env, mutex) {108  return function(specName, fn, timeout) {109    if (110      env != null &&111      !env.specFilter({112        getFullName: () => specName || ''113      })114    ) {115      return originalFn.call(env, specName, () => Promise.resolve(), timeout);116    }117    let promise;118    try {119      promise = mutex(() => {120        const promise = fn();121        if (isPromise(promise)) {122          return promise;123        }124        throw new Error(125          `Jest: concurrent test "${specName}" must return a Promise.`126        );127      });128    } catch (error) {129      return originalFn.call(env, specName, () => Promise.reject(error));130    }131    return originalFn.call(env, specName, () => promise, timeout);132  };133}134function jasmineAsyncInstall(globalConfig, global) {135  const jasmine = global.jasmine;136  const mutex = (0, _throat.default)(globalConfig.maxConcurrency);137  const env = jasmine.getEnv();138  env.it = promisifyIt(env.it, env, jasmine);139  env.fit = promisifyIt(env.fit, env, jasmine);140  global.it.concurrent = (env => {141    const concurrent = makeConcurrent(env.it, env, mutex);142    concurrent.only = makeConcurrent(env.fit, env, mutex);143    concurrent.skip = makeConcurrent(env.xit, env, mutex);144    return concurrent;145  })(env);146  global.fit.concurrent = makeConcurrent(env.fit, env, mutex);147  env.afterAll = promisifyLifeCycleFunction(env.afterAll, env);148  env.afterEach = promisifyLifeCycleFunction(env.afterEach, env);149  env.beforeAll = promisifyLifeCycleFunction(env.beforeAll, env);150  env.beforeEach = promisifyLifeCycleFunction(env.beforeEach, env);...

SemForm.js

Source:SemForm.js

1import React from 'react'2import validation from 'react-validation-mixin'3import strategy from 'react-validatorjs-strategy'4import { Form } from 'semantic-ui-react'5import PropTypes from 'prop-types'6import _ from 'lodash'7class SemForm extends React.Component {8	state = {9		submitted: false,10	}11	static propTypes = {12		source: PropTypes.object.isRequired,13		submitOnEnter: PropTypes.bool,14		onTrySubmit: PropTypes.func, // onTrySubmit when defined will cancel submission of form when false is returned15		onError: PropTypes.func,16		onSuccess: PropTypes.func.isRequired,17		schema: PropTypes.object.isRequired,18		customMessage: PropTypes.object,19		attributeNames: PropTypes.object,20		validationHandler: PropTypes.func,21		onAfterMountForm: PropTypes.func,22	}23	static defaultProps = {24		horizontal: false,25		customMessage: {},26		attributeNames: {},27		submitOnEnter: true,28	}29	static childContextTypes = {30		getErrorText: PropTypes.func,31		checkIsError: PropTypes.func,32		horizontal: PropTypes.bool,33		schema: PropTypes.object,34	}35	getChildContext() {36		return {37			getErrorText: this.getErrorText,38			checkIsError: this.checkIsError,39			horizontal: this.props.horizontal,40			schema: this.props.schema,41		}42	}43	// this is the object validator will look up to when validating44	// in this module, this is accessed from the store45	getValidatorData = () => {46		return this.props.source47	}48	// shows the error message on the HelpBlock49	getErrorText = field => {50		var error = this.props.errors[field]51		var forReturn = ''52		if (_.isArray(error)) {53			_.map(error, err => {54				if (forReturn !== '') {55					forReturn += '; '56				}57				forReturn += err58			})59		} else {60			forReturn = error61		}62		return forReturn63		// if (!error)64		//     return null;65		// if (Array.isArray(error)) {66		//     var message = [];67		//     message = error.map((item, i) => {68		//         return (69		//             <span key={i}>70		//                 {item}71		//                 <br />72		//             </span>73		//         )74		//     });75		//     return message;76		// }77		// else78		//     return (<span>{error || ''}</span>);79	}80	checkIsError = field => {81		if (this.state.submitted) {82			return !this.props.isValid(field)83		} else {84			return false85		}86	}87	onFormSubmit = event => {88		event.preventDefault() // will cancel default formsubmit mechanism we will use ajax89		this.setState(90			{91				submitted: true,92			},93			() => {94				if (this.props.onTrySubmit) {95					if (!this.props.onTrySubmit()) return96				}97				this.props.validate(this.onValidate)98			}99		)100	}101	resetFields = () => {102		this.setState({103			submitted: false,104		})105	}106	onValidate = error => {107		if (error) {108			if (this.props.onError) this.props.onError(error)109		} else {110			if (this.props.onSuccess) this.props.onSuccess()111		}112	}113	componentDidMount() {114		if (this.props.onAfterMountForm) {115			this.props.onAfterMountForm(this)116		}117	}118	submitForm = () => {119		this.refs.hiddenBtn.click()120	}121	checkEnter = e => {122		var txtArea = /textarea/i.test((e.target || e.srcElement).tagName)123		if (txtArea || (e.keyCode || e.which || e.charCode || 0) !== 13) {124			return true125		} else {126			e.preventDefault()127			return false128		}129	}130	render() {131		this.validatorTypes = strategy.createSchema(132			this.props.schema,133			{134				required: 'The field :attribute is required!',135				numeric: 'The field :attribute  should be a number!',136				email: 'The field :attribute should be a valid email!',137			},138			validation => {139				validation.setAttributeNames(this.props.attributeNames)140				if (this.props.validationHandler) this.props.validationHandler(validation)141			}142		)143		return (144			<Form145				onKeyPress={!this.props.submitOnEnter ? this.checkEnter : null}146				onSubmit={this.onFormSubmit}147				style={this.props.style}148			>149				{this.props.children}150				<button style={{ display: 'none' }} type="submit" ref="hiddenBtn" />151			</Form>152		)153	}154}...

authors.js

Source:authors.js

1async function getAllAuthors() {2    const res = await requestToBackend("/api/author", 'GET')3    if (!checkIsError(res)) {4        res.data.forEach(author => {5            $('.body').append(createAuthorCard(author));6        });7    }8}9getAllAuthors()10//Function for adding author via fetch request11$('#add_author').on('submit', async function (e) {12    e.preventDefault()13    const res = await requestToBackend($(this).attr('action'), 'POST', new FormData(this))14    if (!checkIsError(res)) {15        alertShow($('#successAlert'))16        $('.body').append(createAuthorCard(res.data))17    }18})19$('#edit_author').on('submit',async function (e) {20    e.preventDefault()21    const res = await requestToBackend($(this).attr('action'), $(this).attr('method'), new FormData(this))22    if (!checkIsError(res)) {23        alertShow($('.alert-success'))24        editAuthorCard(res.data)25    }26});27//Author card editing function28function editAuthorCard(author) {29    $(`.author-${author.id}`).children("p[id='lastname']").text(author.lastname)30    $(`.author-${author.id}`).children("p[id='name']").text(author.name)31    $(`.author-${author.id}`).children("p[id='patronymic']").text(author.patronymic)32}33//Function to open the author edit window34function openAuthorForm(btn) {35    let authorForm = $(btn).parent().parent()36    let authorNameBox = authorForm.children(".authorName")37    console.log(authorNameBox.children("input[name='id']").val())38    $("input[name='id']").val(authorNameBox.children("input[name='id']").val())39    $("input[name='lastname']").val(authorNameBox.children("p[id='lastname']").text())40    $("input[name='name']").val(authorNameBox.children("p[id='name']").text())41    $("input[name='patronymic']").val(authorNameBox.children("p[id='patronymic']").text())42}43//Function for sending a request to delete an author44async function deleteAuthor(btn) {45    const res = await requestToBackend($(btn).data('link'), 'DELETE')46    if(!checkIsError(res)) {47        alert('ÐÐ²ÑÐ¾Ñ ÑÐ´Ð°Ð»ÐµÐ½')48        $('.author-' + res.data).remove()49    }50}51//Author card creation function52function createAuthorCard(author) {53    return $("<div class=\"card w-100 author-" + author.id + "\">\n" +54        "<div class=\"card-body\">\n" +55        "<form name=\"authorForm\">\n" +56        "<div class=\"authorCard authorName author-" + author.id + "\">\n" +57        "<p class=\"name\" id=\"lastname\" onformdata=\"lastname\">" + author.lastname + "</p>\n" +58        "<p class=\"name\" id=\"name\">" + author.name + "</p>\n" +59        "<p class=\"name\" id=\"patronymic\">" + author.patronymic +"</p>\n" +60        "<input class=\"name\" name=\"id\" readOnly type=\"hidden\" value=\"" + author.id + "\">\n" +...

Jest Testing Tutorial

LambdaTest’s Jest Testing Tutorial covers step-by-step guides around Jest with code examples to help you be proficient with the Jest framework. The Jest tutorial has chapters to help you learn right from the basics of Jest framework to code-based tutorials around testing react apps with Jest, perform snapshot testing, import ES modules and more.

Chapters

What is Jest Framework
Advantages of Jest - Jest has 3,898,000 GitHub repositories, as mentioned on its official website. Learn what makes Jest special and why Jest has gained popularity among the testing and developer community.
Jest Installation - All the prerequisites and set up steps needed to help you start Jest automation testing.
Using Jest with NodeJS Project - Learn how to leverage Jest framework to automate testing using a NodeJS Project.
Writing First Test for Jest Framework - Get started with code-based tutorial to help you write and execute your first Jest framework testing script.
Jest Vocabulary - Learn the industry renowned and official jargons of the Jest framework by digging deep into the Jest vocabulary.
Unit Testing with Jest - Step-by-step tutorial to help you execute unit testing with Jest framework.
Jest Basics - Learn about the most pivotal and basic features which makes Jest special.
Jest Parameterized Tests - Avoid code duplication and fasten automation testing with Jest using parameterized tests. Parameterization allows you to trigger the same test scenario over different test configurations by incorporating parameters.
Jest Matchers - Enforce assertions better with the help of matchers. Matchers help you compare the actual output with the expected one. Here is an example to see if the object is acquired from the correct class or not. -

|it('check_object_of_Car', () => { expect(newCar()).toBeInstanceOf(Car); });| | :- |

Jest Hooks: Setup and Teardown - Learn how to set up conditions which needs to be followed by the test execution and incorporate a tear down function to free resources after the execution is complete.
Jest Code Coverage - Unsure there is no code left unchecked in your application. Jest gives a specific flag called --coverage to help you generate code coverage.
HTML Report Generation - Learn how to create a comprehensive HTML report based on your Jest test execution.
Testing React app using Jest Framework - Learn how to test your react web-application with Jest framework in this detailed Jest tutorial.
Test using LambdaTest cloud Selenium Grid - Run your Jest testing script over LambdaTest cloud-based platform and leverage parallel testing to help trim down your test execution time.
Snapshot Testing for React Front Ends - Capture screenshots of your react based web-application and compare them automatically for visual anomalies with the help of Jest tutorial.
Bonus: Import ES modules with Jest - ES modules are also known as ECMAScript modules. Learn how to best use them by importing in your Jest testing scripts.
Jest vs Mocha vs Jasmine - Learn the key differences between the most popular JavaScript-based testing frameworks i.e. Jest, Mocha, and Jasmine.
Jest FAQs(Frequently Asked Questions) - Explore the most commonly asked questions around Jest framework, with their answers.