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How to use rewriteJsSourceMapAsync method in Cypress

Best JavaScript code snippet using cypress

deferred-source-map-cache.js

Source:deferred-source-map-cache.js

1"use strict";2var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {3    if (k2 === undefined) k2 = k;4    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });5}) : (function(o, m, k, k2) {6    if (k2 === undefined) k2 = k;7    o[k2] = m[k];8}));9var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {10    Object.defineProperty(o, "default", { enumerable: true, value: v });11}) : function(o, v) {12    o["default"] = v;13});14var __importStar = (this && this.__importStar) || function (mod) {15    if (mod && mod.__esModule) return mod;16    var result = {};17    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);18    __setModuleDefault(result, mod);19    return result;20};21var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {22    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }23    return new (P || (P = Promise))(function (resolve, reject) {24        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }25        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }26        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }27        step((generator = generator.apply(thisArg, _arguments || [])).next());28    });29};30var __importDefault = (this && this.__importDefault) || function (mod) {31    return (mod && mod.__esModule) ? mod : { "default": mod };32};33Object.defineProperty(exports, "__esModule", { value: true });34exports.DeferredSourceMapCache = void 0;35const lodash_1 = __importDefault(require("lodash"));36const debug_1 = __importDefault(require("debug"));37const async_rewriters_1 = require("./async-rewriters");38const sourceMaps = __importStar(require("./util/source-maps"));39const url_1 = __importDefault(require("url"));40const debug = (0, debug_1.default)('cypress:rewriter:deferred-source-map-cache');41const caseInsensitiveGet = (obj, lowercaseProperty) => {42    for (let key of Object.keys(obj)) {43        if (key.toLowerCase() === lowercaseProperty) {44            return obj[key];45        }46    }47};48const getSourceMapHeader = (headers) => {49    // sourcemap has precedence50    // @see https://searchfox.org/mozilla-central/rev/dc4560dcaafd79375b9411fdbbaaebb0a59a93ac/devtools/shared/DevToolsUtils.js#611-61951    return caseInsensitiveGet(headers, 'sourcemap') || caseInsensitiveGet(headers, 'x-sourcemap');52};53/**54 * Holds on to data necessary to rewrite user JS to maybe generate a sourcemap at a later time,55 * potentially composed with the user's own sourcemap if one is present.56 *57 * The purpose of this is to avoid wasting CPU time and network I/O on generating, composing, and58 * sending a sourcemap along with every single rewritten JS snippet, since the source maps are59 * going to be unused and discarded most of the time.60 */61class DeferredSourceMapCache {62    constructor(requestLib) {63        this._idCounter = 0;64        this.requests = [];65        this.defer = (request) => {66            if (this._getRequestById(request.uniqueId)) {67                // prevent duplicate uniqueIds from ever existing68                throw new Error(`Deferred sourcemap key "${request.uniqueId}" is not unique`);69            }70            // remove existing requests for this URL since they will not be loaded again71            this._removeRequestsByUrl(request.url);72            this.requests.push(request);73        };74        this.requestLib = requestLib;75    }76    _removeRequestsByUrl(url) {77        lodash_1.default.remove(this.requests, { url });78    }79    _getRequestById(uniqueId) {80        return lodash_1.default.find(this.requests, { uniqueId });81    }82    _getInputSourceMap(request, headers) {83        return __awaiter(this, void 0, void 0, function* () {84            // prefer inline sourceMappingURL over headers85            const sourceMapUrl = sourceMaps.getMappingUrl(request.js) || getSourceMapHeader(request.resHeaders);86            if (!sourceMapUrl) {87                return;88            }89            // try to decode it as a base64 string90            const inline = sourceMaps.tryDecodeInlineUrl(sourceMapUrl);91            if (inline) {92                return inline;93            }94            // try to load it from the web95            const req = {96                url: url_1.default.resolve(request.url, sourceMapUrl),97                // TODO: this assumes that the sourcemap is on the same base domain, so it's safe to send the same headers98                // the browser sent for this sourcemap request - but if sourcemap is on a different domain, this will not99                // be true. need to use browser's cookiejar instead.100                headers,101                timeout: 5000,102            };103            try {104                const { body } = yield this.requestLib(req, true);105                return body;106            }107            catch (error) {108                // eslint-disable-next-line no-console109                debug('got an error loading user-provided sourcemap, serving proxy-generated sourcemap only %o', { url: request.url, headers, error });110            }111        });112    }113    resolve(uniqueId, headers) {114        return __awaiter(this, void 0, void 0, function* () {115            const request = this._getRequestById(uniqueId);116            if (!request) {117                throw new Error(`Missing request with ID '${uniqueId}'`);118            }119            if (request.sourceMap) {120                return request.sourceMap;121            }122            if (!request.js) {123                throw new Error('Missing JS for source map rewrite');124            }125            const inputSourceMap = yield this._getInputSourceMap(request, headers);126            // cache the sourceMap so we don't need to regenerate it127            request.sourceMap = yield (0, async_rewriters_1.rewriteJsSourceMapAsync)(request.url, request.js, inputSourceMap);128            delete request.js; // won't need this again129            delete request.resHeaders;130            return request.sourceMap;131        });132    }133}...

async-rewriters.js

Source:async-rewriters.js

...21        source: js,22    });23}24exports.rewriteJsAsync = rewriteJsAsync;25function rewriteJsSourceMapAsync(url, js, inputSourceMap) {26    return (0, threads_1.queueRewriting)({27        url,28        inputSourceMap,29        sourceMap: true,30        source: js,31    });32}...

Using AI Code Generation

1const fs = require('fs');2const cypress = require('cypress');3const sourceMap = require('source-map');4const sourceMapConsumer = new sourceMap.SourceMapConsumer(fs.readFileSync('main.js.map', 'utf8'));5const sourceMapGenerator = new sourceMap.SourceMapGenerator({ file: 'main.js' });6cypress.run({7    config: {8        onBeforeLoad: (win) => {9            win.rewriteJsSourceMapAsync = (map) => {10                sourceMapConsumer.eachMapping((mapping) => {11                    sourceMapGenerator.addMapping({12                        original: {13                        },14                        generated: {15                        },16                    });17                });18                return sourceMapGenerator.toString();19            };20        },21    },22});23it('should work', () => {24    cy.visit('index.html');25    cy.get('h1').contains('Hello World');26});

Using AI Code Generation

1describe("Test", () => {2    it("Test", () => {3        cy.get("button").click();4        cy.get("input").type("test");5        cy.get("button").click();6        cy.get("h1").should("have.text", "test");7    });8});9import { rewriteJsSourceMapAsync } from "@cypress/webpack-preprocessor";10const { addMatchImageSnapshotPlugin } = require("cypress-image-snapshot/plugin");11const webpackOptions = {12    resolve: {13    },14    module: {15            {16            },17    },18};19module.exports = (on, config) => {20    on("file:preprocessor", async (file) => {21        const options = {22        };23        return await rewriteJsSourceMapAsync(file, options);24    });25    addMatchImageSnapshotPlugin(on, config);26};27const { addMatchImageSnapshotPlugin } = require("cypress-image-snapshot/plugin");28module.exports = (on, config) => {29    addMatchImageSnapshotPlugin(on, config);30    return config;31};32{33    "compilerOptions": {34    },35}36{

Using AI Code Generation

1cy.task('rewriteJsSourceMapAsync', {2});3const { rewriteJsSourceMapAsync } = require('@cypress/source-maps')4module.exports = (on, config) => {5  on('task', {6  })7}8import '@cypress/source-maps/support'

Cypress Tutorial

Cypress is a renowned Javascript-based open-source, easy-to-use end-to-end testing framework primarily used for testing web applications. Cypress is a relatively new player in the automation testing space and has been gaining much traction lately, as evidenced by the number of Forks (2.7K) and Stars (42.1K) for the project. LambdaTest’s Cypress Tutorial covers step-by-step guides that will help you learn from the basics till you run automation tests on LambdaTest.

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Browsers Supported by Cypress - Cypress is built on top of the Electron browser, supporting all modern web browsers. Learn browsers that support Cypress.
Selenium vs Cypress: A Detailed Comparison - Compare and explore some key differences in terms of their design and features.
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