eslint-config-react-app > @typescript-eslint/parser missing typescript?

[peteyycz]

Describe the bug

Running:
npx eslint .
Returns:
Failed to load parser '@typescript-eslint/parser' declared in 'package.json » eslint-config-react-app#overrides[0]': Cannot find module 'typescript'

Did you try recovering your dependencies?

Tried reinstalling everything, sadly it didn't work.

I've also tried installing typescript as described in the error but it was lacking a tsconfig.json and I also doubt I should have one if this is not a typescript project.

Environment

Environment Info:

  current version of create-react-app: 3.4.0
  running from /Users/peteyycz/.nvm/versions/node/v10.19.0/lib/node_modules/create-react-app

  System:
    OS: macOS 10.15.4
    CPU: (4) x64 Intel(R) Core(TM) i5-5257U CPU @ 2.70GHz
  Binaries:
    Node: 10.19.0 - ~/.nvm/versions/node/v10.19.0/bin/node
    Yarn: Not Found
    npm: 6.14.2 - ~/.nvm/versions/node/v10.19.0/bin/npm
  Browsers:
    Chrome: 80.0.3987.149
    Firefox: 74.0
    Safari: 13.1
  npmPackages:
    react: ^16.13.1 => 16.13.1
    react-dom: ^16.13.1 => 16.13.1
    react-scripts: 3.4.1 => 3.4.1
  npmGlobalPackages:
    create-react-app: 3.4.0

Steps to reproduce

(Write your steps here:)

1. npx create-react-app myapp
2. cd myapp
3. npx eslint .

Expected behavior

It should have ran eslint.

Actual behavior

Failed to load parser '@typescript-eslint/parser' declared in 'package.json » eslint-config-react-app#overrides[0]': Cannot find module 'typescript'

Additional resources

Based on my investigation it might be related to how eslint is now resolving configuration:

https://eslint.org/docs/user-guide/migrating-to-6.0.0#package-loading-simplification
Which I have found here:
standard/semistandard#249

EDIT: although now I think about it it's probably a different issue: their case the plugin was missing but in my case the plugin is found but the plugin is missing typescript as a peerdep.

---

https://github.com/facebook/create-react-app/blob/master/packages/eslint-config-react-app/package.json#L19

and this optional: https://github.com/typescript-eslint/typescript-eslint/blob/master/packages/parser/package.json#L56 is not really optional

---

Might also be related
eslint/eslint#12376

[obrejla]

Hi, I have the same problem.

Started to happen once I updated react and react-dom from 16.10.0 and react-scripts from 3.2.0.

$ npx create-react-app --info
npx: installed 99 in 39.462s

Environment Info:

  current version of create-react-app: 3.4.1
  running from C:\Users\ji663\scoop\persist\nodejs\cache\_npx\15068\node_modules\create-react-app

  System:
    OS: Windows 10 10.0.17134
    CPU: (8) x64 Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz
  Binaries:
    Node: 13.1.0 - ~\scoop\apps\nodejs\current\node.EXE
    Yarn: 1.19.1 - ~\scoop\apps\yarn\current\Yarn\bin\yarn.CMD
    npm: 6.12.1 - ~\scoop\apps\nodejs\current\npm.CMD
  Browsers:
    Edge: 42.17134.1098.0
    Internet Explorer: 11.0.17134.1
  npmPackages:
    react: ^16.13.1 => 16.13.1
    react-dom: ^16.13.1 => 16.13.1
    react-scripts: 3.4.1 => 3.4.1
  npmGlobalPackages:
    create-react-app: Not Found

[stale]

This issue has been automatically marked as stale because it has not had any recent activity. It will be closed in 5 days if no further activity occurs.

[alex-benoit]

you can fix this by adding typescript to your dependencies

npm install typescript --save-dev

[Chernavskikh]

Having a same problem with latest create-react-app version

[Annis-Monadjem]

having exact same problem:

Kernel: 4.15.0-99-generic x86_64 bits: 64 compiler: gcc v: 7.5.0 Desktop: Xfce 4.14.1
Distro: Linux Mint 19.3 Tricia base: Ubuntu 18.04 bionic

[damien-git]

I think this is related to #6834 (reported on April 2019).

[tnovau]

yarn add -D typescript

[stale]

This issue has been automatically marked as stale because it has not had any recent activity. It will be closed in 5 days if no further activity occurs.