regression: Cypress 9.1.0 throws when code coverage is enabled, failing every test

Current behavior

every test fails with a crash

Desired behavior

Test code to reproduce

upgrade cypress to 9.1.0 with a project that has followed instructions for enabling instrumenting and code coverage. Failure is in both cypress open and cypress open-ct

Cypress Version

9.1.0

Other

Tested with Cypress 8.3.1 -> 9.1.0. Every version of Cypress except 9.1.0 successfully runs tests with code coverage enabled, version 9.1.0 fails

  "optionalDependencies": {
    "@cypress/code-coverage": "3.9.10",
    "@cypress/react": "5.9.4",
    "@cypress/webpack-dev-server": "1.4.0",
    "@cypress/webpack-preprocessor": "5.9.1",
    "@istanbuljs/nyc-config-typescript": "1.0.1",
    "@jsdevtools/coverage-istanbul-loader": "3.0.5",
    "@testing-library/cypress": "8.0.1",
    "@types/cypress-cucumber-preprocessor": "4.0.1",
    "babel-plugin-istanbul": "6.0.0",
    "cypress": "9.1.0",
    "cypress-cucumber-preprocessor": "4.2.0",
    "cypress-file-upload": "5.0.8",
    "cypress-iframe": "1.0.1",
    "cypress-real-events": "1.5.1"
  }

cypress.json:

{
  "baseUrl": "http://localhost:6007",
  "integrationFolder": "../src",
  "testFiles": "**/integration_tests/**/*.{test.tsx,test.ts,feature}",
  "video": false,
  "component": {
    "componentFolder": "../../",
    "testFiles": "**/component_tests/**/*.{test.tsx,test.ts}"
  }
}

code coverage-related plugins code (it’s all standard stuff):

plugins/index.js

/* eslint-disable @typescript-eslint/no-var-requires */
/// <reference types="cypress" />
// ***********************************************************
// This example plugins/index.js can be used to load plugins
//
// You can change the location of this file or turn off loading
// the plugins file with the 'pluginsFile' configuration option.
//
// You can read more here:
// https://on.cypress.io/plugins-guide
// ***********************************************************

const resolve = require("resolve");
const path = require("path");

// This function is called when a project is opened or re-opened (e.g. due to
// the project's config changing)
const preprocessor = require("@cypress/webpack-preprocessor");
const codeCoverage = require("@cypress/code-coverage/task");
const cucumber = require("cypress-cucumber-preprocessor").default;
const browserify = require("@cypress/browserify-preprocessor");
const webpackOptions = require("./webpack.config");
const tsConfig = require("../../../../../tsconfig.common.json");

/**
 * @type {Cypress.PluginConfig}
 */
module.exports = (on, config) => {
  const cucumberOptions = {
    ...browserify.defaultOptions,
    typescript: resolve.sync("typescript", { baseDir: config.projectRoot }),
  };

  cucumberOptions.browserifyOptions.transform.unshift([
    // There is absolutely a better way to share these resources, but this is the best
    // I can do given the constraints of git, file links, and the monorepo we live with
    path.resolve("..", "..", "..", "e2e", "cypress", "plugins", "aliaser.js"),
    {
      aliases: tsConfig.compilerOptions.paths,
      baseDir: path.resolve("..", "..", ".."),
    },
  ]);

  if (config.testingType === "component") {
    const { startDevServer } = require("@cypress/webpack-dev-server");

    on("dev-server:start", (options) => startDevServer({ options, webpackConfig: webpackOptions }));
  } else {
    on("file:preprocessor", (file) =>
      file.filePath.includes(".feature") ? cucumber(cucumberOptions)(file) : preprocessor({ webpackOptions })(file)
    );
  }
  codeCoverage(on, config);
  return config;
};

support/index.js

// ***********************************************************
// This example support/index.js is processed and
// loaded automatically before your test files.
//
// This is a great place to put global configuration and
// behavior that modifies Cypress.
//
// You can change the location of this file or turn off
// automatically serving support files with the
// 'supportFile' configuration option.
//
// You can read more here:
// https://on.cypress.io/configuration
// ***********************************************************

// Import commands.js using ES2015 syntax:
import "./commands";
// Alternatively you can use CommonJS syntax:
// require('./commands')
import "@cypress/code-coverage/support";
import "cypress-real-events/support";

[tmieulet]

9.1.1 fixed this issue. Thanks

[cellog]

I’ll try on Monday, thanks so much for the response!