process.node.env is undefined in eslintrc.js

Question

I need some linting rules to throw either an error or a warning depending on whether the build is development or production. In a React component file during development process.env.NODE_ENV === 'development'.

In eslintrc.js I have:

const production = process.env.NODE_ENV !== 'development'; // returns true
console.log('%c process.env.NODE_ENV', 'color: green;', process.env.NODE_ENV); // returns undefined

I want to be able to switch between linting rule warnings. and errors like this:

    rules: {
        'no-tabs': 0,
        indent: [2, 'tab', { SwitchCase: 1, VariableDeclarator: 1 }],
        'react/jsx-props-no-spreading': 'off',
        'no-unused-vars':
            production
                ? 'error'
                : 'warn',

Why is process.env.NODE_ENV undefined and how can I fix this?

I would imagine any environment variables would be undefined during static analysis in your IDE since the code isn't actually running in an environment. — Drew Reese
– Drew Reese, Commented Oct 30, 2020 at 17:22

Nikola.Lukovic · Accepted Answer · 2020-11-17 21:52:35Z

2

Since it's undefined during static analysis you can always do something like this:

  'no-console': (() => {
      if (typeof process.env.NODE_ENV === 'undefined') {
        return 'off';
      }

      if (process.env.NODE_ENV === 'development') {
        return 'off';
      }

      return 'error';
    })(),

answered Nov 17, 2020 at 21:52

Nikola.Lukovic

1,3551 gold badge16 silver badges35 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Nagisa Ando Over a year ago

I was struggling to set rule only to development and this works for me! Thank you so much!

Michael Abeln · Accepted Answer · 2020-10-30 17:49:49Z

0

You might think about just having multiple configuration files for eslint instead of trying to handle environment changes in a single file.

According to the docs: https://eslint.org/docs/user-guide/command-line-interface#basic-configuration

You can just call eslint with the -c or --config flags and pass in the extra config file. This will merge a base config file with the file passed in the flag

An example for two lint scripts:
eslint --config ./dev-config.js **/*.js
eslint --config ./prod-config.js **/*.js

answered Oct 30, 2020 at 17:49

Michael Abeln

2,58713 silver badges21 bronze badges

Collectives™ on Stack Overflow

process.node.env is undefined in eslintrc.js

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related