Existing eslint rule configuration fails starting in 3.1.0

Describe the bug

After upgrading to 3.1.1 (and 3.1.0) it’s no longer possible to configure eslint rules that are part of the editor configuration. yarn start will fail with an error about an eslint rule it doesn’t know about.

Definition for rule 'graphql/template-strings' was not found  graphql/template-strings

This makes sense since starting with eslint@6 it will raise errors when attempting to configure unknown rules. However I do not expect existing projects to break because they’ve decided to setup editor only eslint configuration.

I guess eventually this could be solved with the experimental eslint extension, but that’s still experimental unfortunately and still seems to have issues of it’s own.

Did you try recovering your dependencies?

n.a.

Which terms did you search for in User Guide?

https://create-react-app.dev/docs/setting-up-your-editor https://create-react-app.dev/docs/troubleshooting

Environment

Environment Info:

  System:
    OS: macOS 10.14.6
    CPU: (8) x64 Intel(R) Core(TM) i7-4870HQ CPU @ 2.50GHz
  Binaries:
    Node: 8.15.0 - ~/.asdf/shims/node
    Yarn: 1.17.3 - /usr/local/bin/yarn
    npm: 6.4.1 - ~/.asdf/shims/npm
  Browsers:
    Chrome: Not Found
    Firefox: 68.0.2
    Safari: Not Found
  npmPackages:
    react: ^16.9.0 => 16.9.0
    react-dom: ^16.9.0 => 16.9.0
    react-scripts: 3.1.1 => 3.1.1
  npmGlobalPackages:
    create-react-app: Not Found

Steps to reproduce

1. npx create-react-app test-app
2. cd test-app
3. yarn add -D eslint-config-prettier

4.  echo "module.exports = {
      extends: [
        'react-app',
        'prettier/prettier',
      ],
      plugins: ['prettier']
    }
    " > .eslintrc.js
   

5. echo "/* eslint-disable prettier/prettier */" >> src/App.js
6. yarn start

Expected behavior

The app to continue to be started. At least in the case of an already existing app with already existing editor configuration.

Actual behavior

Definition for rule 'prettier/prettier' was not found  prettier/prettier

Reproducible demo

https://github.com/klaaspieter/create-react-app-eslint-editor-configuration

[micahstubbs]

also experiencing this bug with my existing eslint config

[rovansteen]

I was just pointing out that create-react-app just ignored custom eslint rules before. And as far as I know that should still be the case if EXTEND_ESLINT is set to false so if that is breaking your build that sounds like a bug.