Stuck on an issue?

Lightrun Answers was designed to reduce the constant googling that comes with debugging 3rd party libraries. It collects links to all the places you might be looking at while hunting down a tough bug.

And, if you’re still stuck at the end, we’re happy to hop on a call to see how we can help out.

Cypress cannot start with importHelpers and allowJS TypeScript options

See original GitHub issue

Current behavior:

Attempting to launch Cypress with this tsconfig results in the following exception:

{
  "compilerOptions": {
    "importHelpers": true,
    "allowJs": true
  }
}

Error: Cannot find module 'tslib'
Require stack:
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\reporter\lib\resolve-dist.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\controllers\reporter.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\routes.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\server.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\project.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\gui\events.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\modes\interactive.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\modes\index.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\cypress.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\index.js
- C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\index.js
- 
    at Module._resolveFilename (internal/modules/cjs/loader.js:798:15)
    at Function../lib/common/reset-search-paths.ts.Module._resolveFilename (electron/js2c/browser_init.js:7630:16)
    at Module._load (internal/modules/cjs/loader.js:691:27)
    at Module._load (electron/js2c/asar.js:717:26)
    at Function.Module._load (electron/js2c/asar.js:717:26)
    at Function.Module._load (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\override_require.js:18:25)
    at Module.require (internal/modules/cjs/loader.js:853:19)
    at require (internal/modules/cjs/helpers.js:74:18)
    at Object.<anonymous> (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\reporter\lib\resolve-dist.js:1:15)
    at Module._compile (internal/modules/cjs/loader.js:968:30)
    at Module.m._compile (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\ts-node\src\index.ts:536:23)
    at Module._extensions..js (internal/modules/cjs/loader.js:986:10)
    at Object.require.extensions.<computed> [as .js] (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\ts-node\src\index.ts:539:12)
    at Module.load (internal/modules/cjs/loader.js:816:32)
    at Module._load (internal/modules/cjs/loader.js:728:14)
    at Module._load (electron/js2c/asar.js:717:26)
    at Function.Module._load (electron/js2c/asar.js:717:26)
    at Function.Module._load (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\override_require.js:18:25)
    at Module.require (internal/modules/cjs/loader.js:853:19)
    at require (internal/modules/cjs/helpers.js:74:18)
    at Object.<anonymous> (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\controllers\reporter.js:8:14)
    at Object.<anonymous> (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\controllers\reporter.js:18:4)
    at Module._compile (internal/modules/cjs/loader.js:968:30)
    at Module.m._compile (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\ts-node\src\index.ts:536:23)
    at Module._extensions..js (internal/modules/cjs/loader.js:986:10)
    at Object.require.extensions.<computed> [as .js] (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\ts-node\src\index.ts:539:12)
    at Module.load (internal/modules/cjs/loader.js:816:32)
    at Module._load (internal/modules/cjs/loader.js:728:14)
    at Module._load (electron/js2c/asar.js:717:26)
    at Function.Module._load (electron/js2c/asar.js:717:26)
    at Function.Module._load (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\override_require.js:18:25)
    at Module.require (internal/modules/cjs/loader.js:853:19)
    at require (internal/modules/cjs/helpers.js:74:18)
    at Object.<anonymous> (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\routes.js:9:18)
    at Module._compile (internal/modules/cjs/loader.js:968:30)
    at Module.m._compile (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\ts-node\src\index.ts:536:23)
    at Module._extensions..js (internal/modules/cjs/loader.js:986:10)
    at Object.require.extensions.<computed> [as .js] (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\ts-node\src\index.ts:539:12)
    at Module.load (internal/modules/cjs/loader.js:816:32)
    at Module._load (internal/modules/cjs/loader.js:728:14)
    at Module._load (electron/js2c/asar.js:717:26)
    at Function.Module._load (electron/js2c/asar.js:717:26)
    at Function.Module._load (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\override_require.js:18:25)
    at Module.require (internal/modules/cjs/loader.js:853:19)
    at require (internal/modules/cjs/helpers.js:74:18)
    at Server.createRoutes (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\server.js:159:14)
    at C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\server.js:205:17
    at tryCatcher (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\util.js:16:23)
    at Function.Promise.attempt.Promise.try (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\method.js:39:29)
    at Server.open (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\server.js:180:28)
    at C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\lib\project.js:135:26
    at tryCatcher (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\util.js:16:23)
    at Promise._settlePromiseFromHandler (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\promise.js:547:31)
    at Promise._settlePromise (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\promise.js:604:18)
    at Promise._settlePromise0 (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\promise.js:649:10)
    at Promise._settlePromises (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\promise.js:729:18)
    at _drainQueueStep (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\async.js:93:12)
    at _drainQueue (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\async.js:86:9)
    at Async._drainQueues (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\async.js:102:5)
    at Immediate.Async.drainQueues [as _onImmediate] (C:\Users\adgastin\AppData\Local\Cypress\Cache\4.7.0\Cypress\resources\app\packages\server\node_modules\bluebird\js\release\async.js:15:14)
    at processImmediate (internal/timers.js:439:21)

Removing either flag fixes the error. tslib is forcibly installed to guarantee there is no issue resolving it.

This appears to occur regardless of what is in the Cypress tsconfig, so as long as the parent project contains this config, Cypress cannot start.

Versions

Cypress 4.6.0 - 4.7.0

Issue Analytics

State:
Created 3 years ago
Reactions:5
Comments:16 (4 by maintainers)

Top GitHub Comments

6reactions

Hypercubedcommented, Jun 29, 2020

According to the docs (https://docs.cypress.io/guides/tooling/typescript-support.html#Configure-tsconfig-json) we should be able to use a tsconfig.json inside the cypress directory to set importHelpers false… but that doesn’t appear to work for me.

6reactions

garvikcommented, May 28, 2020

I’m getting the same error using any version that’s >= 4.4.0. Works fine in 4.3.0.

Top Results From Across the Web

Cypress causing type errors in jest assertions - Stack Overflow

I installed Cypress yesterday, and now I'm getting Typescript errors on all my jest matchers: Property 'toEqual' doesn't exist on type ' ...

Understanding TypeScript Configuration Options

When allowJs is true , TypeScript will allow JavaScript files to be compiled but, it will not do type-checking. Here's some example file...

importHelpers - TypeScript: TSConfig Option

You will need to ensure that the tslib module is able to be imported at runtime. This only affects modules; global script files...

jsconfig.json Reference - Visual Studio Code

The jsconfig.json file specifies the root files and the options for the features ... file for TypeScript. jsconfig.json is tsconfig.json with "allowJs" ...

Typescript does not resolve modules through tsconfig.json's ...

So,it doesn't use settings in your tsconfig.json when compiling your files, ... did you try re-starting the Typescript service using Restart ...