fix: retry on EMFILE always, lint sync FS calls

.eslintrc.js

@@ -5,6 +5,7 @@ const { specifiedRules } = require('graphql')
 const graphqlOpts = {
   env: 'literal',
   tagName: 'gql',
+  // eslint-disable-next-line no-restricted-syntax
   schemaString: fs.readFileSync(
     path.join(__dirname, 'packages/graphql/schemas/schema.graphql'),
     'utf8',
@@ -33,6 +34,24 @@ module.exports = {
     'plugin:@cypress/dev/tests',
   ],
   parser: '@typescript-eslint/parser',
+  overrides: [
+    {
+      files: [
+        // ignore in tests and scripts
+        '**/scripts/**',
+        '**/test/**',
+        '**/system-tests/**',
+        'packages/{app,driver,frontend-shared,launchpad}/cypress/**',
+        '*.test.ts',
+        // ignore in packages that don't run in the Cypress process
+        'npm/create-cypress-tests/**',
+      ],
+      rules: {
+        'no-restricted-properties': 'off',
+        'no-restricted-syntax': 'off',
+      },
+    },
+  ],
   rules: {
     'no-duplicate-imports': 'off',
     'import/no-duplicates': 'off',
@@ -55,6 +74,16 @@ module.exports = {
         message: 'os.userInfo() will throw when there is not an `/etc/passwd` entry for the current user (like when running with --user 12345 in Docker). Do not use it unless you catch any potential errors.',
       },
     ],
+    'no-restricted-syntax': [
+      // esquery tool: https://estools.github.io/esquery/
+      'error',
+      {
+        // match sync FS methods except for `existsSync`
+        // examples: fse.readFileSync, fs.readFileSync, this.ctx.fs.readFileSync...
+        selector: `MemberExpression[object.name='fs'][property.name=/^[A-z]+Sync$/]:not(MemberExpression[property.name='existsSync']), MemberExpression[property.name=/^[A-z]+Sync$/]:not(MemberExpression[property.name='existsSync']):has(MemberExpression[property.name='fs'])`,
+        message: 'Synchronous fs calls should not be used in Cypress. Use an async API instead.',
+      },
+    ],
     'graphql/capitalized-type-name': ['warn', graphqlOpts],
     'graphql/no-deprecated-fields': ['error', graphqlOpts],
     'graphql/template-strings': ['error', { ...graphqlOpts, validators }],

npm/eslint-plugin-dev/lib/custom-rules/index.js

@@ -2,6 +2,7 @@ const fs = require('fs')
 const path = require('path')
 
 module.exports =
+  // eslint-disable-next-line no-restricted-syntax
   Object.assign({}, ...fs.readdirSync(__dirname)
   .filter((filename) => filename.endsWith('.js') && filename !== 'index.js')
   .map((filename) => ({ [filename.replace(/\.js$/u, '')]: require(path.resolve(__dirname, filename)) })))

npm/vite-dev-server/cypress/e2e/vite-dev-server.cy.ts

@@ -38,7 +38,7 @@ describe('Config options', () => {
     cy.startAppServer('component')
 
     cy.withCtx(async (ctx, { specWithWhitespace }) => {
-      ctx.actions.file.writeFileInProject(
+      await ctx.actions.file.writeFileInProject(
         ctx.path.join('src', specWithWhitespace),
         await ctx.file.readFileInProject(ctx.path.join('src', 'App.cy.jsx')),
       )

npm/vite-dev-server/src/plugins/cypress.ts

@@ -38,6 +38,8 @@ export const Cypress = (
   const indexHtmlFile = options.cypressConfig.indexHtmlFile
 
   let specsPathsSet = getSpecsPathsSet(specs)
+  // TODO: use async fs methods here
+  // eslint-disable-next-line no-restricted-syntax
   let loader = fs.readFileSync(INIT_FILEPATH, 'utf8')
 
   devServerEvents.on('dev-server:specs:changed', (specs: Spec[]) => {

npm/webpack-dev-server/src/CypressCTWebpackPlugin.ts

@@ -99,13 +99,15 @@ export class CypressCTWebpackPlugin {
    * has been "updated on disk", causing a recompliation (and pulling the new specs in as
    * dependencies).
    */
-  private onSpecsChange = (specs: Cypress.Cypress['spec'][]) => {
+  private onSpecsChange = async (specs: Cypress.Cypress['spec'][]) => {
     if (!this.compilation || _.isEqual(specs, this.files)) {
       return
     }
 
     this.files = specs
     const inputFileSystem = this.compilation.inputFileSystem
+    // TODO: don't use a sync fs method here
+    // eslint-disable-next-line no-restricted-syntax
     const utimesSync: UtimesSync = inputFileSystem.fileSystem.utimesSync ?? fs.utimesSync
 
     utimesSync(path.resolve(__dirname, 'browser.js'), new Date(), new Date())

npm/webpack-dev-server/src/helpers/nextHandler.ts

@@ -69,7 +69,7 @@ async function loadWebpackConfig (devServerConfig: WebpackDevServerConfig): Prom
       buildId: `@cypress/react-${Math.random().toString()}`,
       config: nextConfig,
       dev: true,
-      pagesDir: findPagesDir(devServerConfig.cypressConfig.projectRoot),
+      pagesDir: await findPagesDir(devServerConfig.cypressConfig.projectRoot),
       entrypoints: {},
       rewrites: { fallback: [], afterFiles: [], beforeFiles: [] },
       ...runWebpackSpan,
@@ -106,9 +106,9 @@ function checkSWC (
   return false
 }
 
-const existsSync = (file: string) => {
+const exists = async (file: string) => {
   try {
-    fs.accessSync(file, fs.constants.F_OK)
+    await fs.promises.access(file, fs.constants.F_OK)
 
     return true
   } catch (_) {
@@ -121,16 +121,16 @@ const existsSync = (file: string) => {
  * `${projectRoot}/pages` or `${projectRoot}/src/pages`.
  * If neither is found, return projectRoot
  */
-function findPagesDir (projectRoot: string) {
+async function findPagesDir (projectRoot: string) {
   // prioritize ./pages over ./src/pages
   let pagesDir = path.join(projectRoot, 'pages')
 
-  if (existsSync(pagesDir)) {
+  if (await exists(pagesDir)) {
     return pagesDir
   }
 
   pagesDir = path.join(projectRoot, 'src', 'pages')
-  if (existsSync(pagesDir)) {
+  if (await exists(pagesDir)) {
     return pagesDir
   }
 

npm/webpack-dev-server/src/measureWebpackPerformance.ts

@@ -1,3 +1,4 @@
+/* eslint-disable no-restricted-syntax */
 /* eslint-disable no-console */
 import path from 'path'
 import fs from 'fs'

npm/webpack-preprocessor/package.json

@@ -11,7 +11,7 @@
     "secure": "nsp check",
     "semantic-release": "semantic-release",
     "size": "npm pack --dry",
-    "test": "node ./test-webpack-5.js",
+    "test": "node ./scripts/test-webpack-5.js",
     "test-debug": "node --inspect --debug-brk ./node_modules/.bin/_mocha",
     "test-e2e": "mocha test/e2e/*.spec.*",
     "test-unit": "mocha test/unit/*.spec.*",

npm/webpack-preprocessor/test-webpack-5.js → npm/webpack-preprocessor/scripts/test-webpack-5.js

@@ -1,7 +1,10 @@
 const execa = require('execa')
-const pkg = require('./package.json')
+const path = require('path')
+const pkg = require('../package.json')
 const fs = require('fs')
 
+const pkgJsonPath = path.join(__dirname, '..', 'package.json')
+
 /**
  * This file installs Webpack 5 and runs the unit and e2e tests for the preprocessor.
  * We read package.json, update the webpack version, then re-run yarn install.
@@ -17,7 +20,7 @@ const main = async () => {
   const install = () => execa('yarn', ['install', '--ignore-scripts'], { stdio: 'inherit' })
 
   const resetPkg = async () => {
-    fs.writeFileSync('package.json', originalPkg, 'utf8')
+    fs.writeFileSync(pkgJsonPath, originalPkg, 'utf8')
     await install()
   }
 
@@ -38,7 +41,7 @@ const main = async () => {
   delete pkg.devDependencies['webpack']
   // eslint-disable-next-line no-console
   console.log('[@cypress/webpack-preprocessor]: updating package.json...')
-  fs.writeFileSync('package.json', JSON.stringify(pkg, null, 2))
+  fs.writeFileSync(pkgJsonPath, JSON.stringify(pkg, null, 2))
 
   // eslint-disable-next-line no-console
   console.log('[@cypress/webpack-preprocessor]: install dependencies...')

packages/app/cypress/e2e/cypress-in-cypress-component.cy.ts

@@ -208,8 +208,8 @@ describe('Cypress In Cypress CT', { viewportWidth: 1500, defaultCommandTimeout:
         }).invoke('connected').should('be.true')
       })
 
-      cy.withCtx((ctx, o) => {
-        ctx.actions.file.writeFileInProject(o.path, `
+      cy.withCtx(async (ctx, o) => {
+        await ctx.actions.file.writeFileInProject(o.path, `
   import React from 'react'
   import { mount } from '@cypress/react'
 

packages/app/cypress/e2e/cypress-in-cypress-e2e.cy.ts

@@ -259,8 +259,8 @@ describe('Cypress In Cypress E2E', { viewportWidth: 1500, defaultCommandTimeout:
       }).invoke('connected').should('be.true')
     })
 
-    cy.withCtx((ctx, o) => {
-      ctx.actions.file.writeFileInProject(o.path, `
+    cy.withCtx(async (ctx, o) => {
+      await ctx.actions.file.writeFileInProject(o.path, `
 describe('Dom Content', () => {
   it('renders the new test content', () => {
     cy.visit('cypress/e2e/dom-content.html')

packages/app/cypress/e2e/cypress-in-cypress.cy.ts

@@ -228,13 +228,13 @@ describe('Cypress in Cypress', { viewportWidth: 1500, defaultCommandTimeout: 100
     startAtSpecsPage('e2e')
     cy.get('[data-cy="spec-item"]')
 
-    cy.withCtx((ctx, o) => {
+    cy.withCtx(async (ctx, o) => {
       ctx.coreData.app.browserStatus = 'open'
 
-      let config = ctx.actions.file.readFileInProject('cypress.config.js')
+      let config = await ctx.actions.file.readFileInProject('cypress.config.js')
 
       config = config.replace(`e2e: {`, `e2e: {\n  chromeWebSecurity: false,\n`)
-      ctx.actions.file.writeFileInProject('cypress.config.js', config)
+      await ctx.actions.file.writeFileInProject('cypress.config.js', config)
 
       o.sinon.stub(ctx.actions.browser, 'closeBrowser')
       o.sinon.stub(ctx.actions.browser, 'relaunchBrowser')
@@ -252,24 +252,24 @@ describe('Cypress in Cypress', { viewportWidth: 1500, defaultCommandTimeout: 100
   it('restarts browser if there is a before:browser:launch task and there is a change on the config', () => {
     startAtSpecsPage('e2e')
 
-    cy.withCtx((ctx, o) => {
+    cy.withCtx(async (ctx, o) => {
       ctx.coreData.app.browserStatus = 'open'
 
-      let config = ctx.actions.file.readFileInProject('cypress.config.js')
+      let config = await ctx.actions.file.readFileInProject('cypress.config.js')
 
       config = config.replace(`e2e: {`, `e2e: {\n  setupNodeEvents(on) {\n on('before:browser:launch', () => {})\n},\n`)
-      ctx.actions.file.writeFileInProject('cypress.config.js', config)
+      await ctx.actions.file.writeFileInProject('cypress.config.js', config)
     })
 
     cy.get('[data-cy="spec-item"]')
 
-    cy.withCtx((ctx, o) => {
+    cy.withCtx(async (ctx, o) => {
       ctx.coreData.app.browserStatus = 'open'
 
-      let config = ctx.actions.file.readFileInProject('cypress.config.js')
+      let config = await ctx.actions.file.readFileInProject('cypress.config.js')
 
       config = config.replace(`e2e: {`, `e2e: {\n  viewportHeight: 600,\n`)
-      ctx.actions.file.writeFileInProject('cypress.config.js', config)
+      await ctx.actions.file.writeFileInProject('cypress.config.js', config)
 
       o.sinon.stub(ctx.actions.browser, 'closeBrowser')
       o.sinon.stub(ctx.actions.browser, 'relaunchBrowser')
@@ -288,14 +288,14 @@ describe('Cypress in Cypress', { viewportWidth: 1500, defaultCommandTimeout: 100
     startAtSpecsPage('e2e')
     cy.get('[data-cy="spec-item"]')
 
-    cy.withCtx((ctx, o) => {
+    cy.withCtx(async (ctx, o) => {
       ctx.coreData.app.browserStatus = 'open'
       o.sinon.stub(ctx.actions.project, 'initializeActiveProject')
 
-      let config = ctx.actions.file.readFileInProject('cypress.config.js')
+      let config = await ctx.actions.file.readFileInProject('cypress.config.js')
 
       config = config.replace(`{`, `{\n  watchForFileChanges: false,\n`)
-      ctx.actions.file.writeFileInProject('cypress.config.js', config)
+      await ctx.actions.file.writeFileInProject('cypress.config.js', config)
     })
 
     cy.get('[data-cy="loading-spinner"]').should('be.visible')

packages/app/cypress/e2e/specs.cy.ts

@@ -423,7 +423,7 @@ describe('App: Specs', () => {
 
         it('generates spec with file name that does not contain a known spec extension', () => {
           cy.withCtx(async (ctx) => {
-            let config = ctx.actions.file.readFileInProject('cypress.config.js')
+            let config = await ctx.actions.file.readFileInProject('cypress.config.js')
 
             config = config.replace(
                 `specPattern: 'src/**/*.{cy,spec}.{js,jsx}'`,
@@ -700,7 +700,7 @@ describe('App: Specs', () => {
 
       it('generates spec with file name that does not contain a known spec extension', () => {
         cy.withCtx(async (ctx) => {
-          let config = ctx.actions.file.readFileInProject('cypress.config.js')
+          let config = await ctx.actions.file.readFileInProject('cypress.config.js')
 
           config = config.replace(
               `specPattern: 'src/specs-folder/*.cy.{js,jsx}'`,

packages/app/cypress/e2e/subscriptions/configChange-subscription.cy.ts

@@ -1,18 +1,18 @@
 function updateProjectIdInCypressConfig (value: string) {
-  return cy.withCtx((ctx, o) => {
-    let config = ctx.actions.file.readFileInProject('cypress.config.js')
+  return cy.withCtx(async (ctx, o) => {
+    let config = await ctx.actions.file.readFileInProject('cypress.config.js')
 
     config = config.replace(`projectId: 'abc123'`, `projectId: '${o.value}'`)
-    ctx.actions.file.writeFileInProject('cypress.config.js', config)
+    await ctx.actions.file.writeFileInProject('cypress.config.js', config)
   }, { value })
 }
 
 function updateViewportHeightInCypressConfig (value: number) {
-  return cy.withCtx((ctx, o) => {
-    let config = ctx.actions.file.readFileInProject('cypress.config.js')
+  return cy.withCtx(async (ctx, o) => {
+    let config = await ctx.actions.file.readFileInProject('cypress.config.js')
 
     config = config.replace(`e2e: {`, `e2e: {\n  viewportHeight: ${o.value},\n`)
-    ctx.actions.file.writeFileInProject('cypress.config.js', config)
+    await ctx.actions.file.writeFileInProject('cypress.config.js', config)
   }, { value })
 }
 

packages/app/cypress/e2e/subscriptions/specChange-subscription.cy.ts

@@ -18,8 +18,8 @@ describe('specChange subscription', () => {
       .should('contain', 'dom-content.spec.js')
       .should('contain', 'dom-list.spec.js')
 
-      cy.withCtx((ctx, o) => {
-        ctx.actions.file.writeFileInProject(o.path, '')
+      cy.withCtx(async (ctx, o) => {
+        await ctx.actions.file.writeFileInProject(o.path, '')
       }, { path: getPathForPlatform('cypress/e2e/new-file.spec.js') })
 
       cy.get('[data-cy="spec-item-link"]')

packages/data-context/src/actions/FileActions.ts

@@ -8,29 +8,29 @@ import assert from 'assert'
 export class FileActions {
   constructor (private ctx: DataContext) {}
 
-  readFileInProject (relativePath: string): string {
+  async readFileInProject (relativePath: string): Promise<string> {
     if (!this.ctx.currentProject) {
       throw new Error(`Cannot write file in project without active project`)
     }
 
     const filePath = path.join(this.ctx.currentProject, relativePath)
 
-    this.ctx.fs.ensureDirSync(path.dirname(filePath))
+    await this.ctx.fs.ensureDir(path.dirname(filePath))
 
-    return this.ctx.fs.readFileSync(filePath, 'utf-8')
+    return this.ctx.fs.readFile(filePath, 'utf-8')
   }
 
-  writeFileInProject (relativePath: string, data: any) {
+  async writeFileInProject (relativePath: string, data: any) {
     if (!this.ctx.currentProject) {
       throw new Error(`Cannot write file in project without active project`)
     }
 
     const filePath = path.join(this.ctx.currentProject, relativePath)
 
-    this.ctx.fs.ensureDirSync(path.dirname(filePath))
+    await this.ctx.fs.ensureDir(path.dirname(filePath))
 
     // Typically used in e2e tests, simpler than forcing async
-    this.ctx.fs.writeFileSync(
+    await this.ctx.fs.writeFile(
       filePath,
       data,
     )
@@ -42,7 +42,7 @@ export class FileActions {
     }
 
     // Typically used in e2e tests, simpler than forcing async
-    this.ctx.fs.removeSync(path.join(this.ctx.currentProject, relativePath))
+    await this.ctx.fs.remove(path.join(this.ctx.currentProject, relativePath))
   }
 
   async moveFileInProject (relativePath: string, toRelativePath: string) {
@@ -51,7 +51,7 @@ export class FileActions {
     }
 
     // Typically used in e2e tests, simpler than forcing async
-    this.ctx.fs.moveSync(
+    await this.ctx.fs.move(
       path.join(this.ctx.currentProject, relativePath),
       path.join(this.ctx.currentProject, toRelativePath),
     )