process.env.STORYBOOK is no longer true

[RyanMacBern]

Describe the bug
I depend on the process.env.STORYBOOK being true to to setup the environment properly for Storybook. After upgrading from 6.4.9 to 6.4.18 the value is no longer true and Storybook fails to run for my setup.

To Reproduce
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System
System:
OS: macOS 12.1
CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
Binaries:
Node: 16.13.0 - ~/.nvm/versions/node/v16.13.0/bin/node
Yarn: 1.22.17 - ~/.nvm/versions/node/v16.13.0/bin/yarn
npm: 8.1.4 - ~/.nvm/versions/node/v16.13.0/bin/npm
Browsers:
Chrome: 98.0.4758.80
Firefox: 96.0.3
Safari: 15.2
npmPackages:
@storybook/addon-actions: 6.4.18 => 6.4.18
@storybook/addon-essentials: 6.4.18 => 6.4.18
@storybook/addon-interactions: ^6.4.18 => 6.4.18
@storybook/addon-links: 6.4.18 => 6.4.18
@storybook/addon-storyshots: 6.4.18 => 6.4.18
@storybook/addons: 6.4.18 => 6.4.18
@storybook/node-logger: 6.4.18 => 6.4.18
@storybook/preset-create-react-app: ^3.1.5 => 3.2.0
@storybook/react: 6.4.18 => 6.4.18
@storybook/testing-library: ^0.0.9 => 0.0.9

Additional context
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[shilman]

I can't reproduce? Are you referring to it as process.env.STORYBOOK? Is this in dev mode or static build?

Can you share a reproduction? See how to create a repro. If so, I'd be happy to take a look. Thanks!

[RyanMacBern]

@shilman

Turns out it's a Webpack 5 issue. We upgraded to Webpack 5 which no longer includes a polyfill for destructuring multiple values from process.env. See webpack/webpack#14800.

I worked around it by changing from this:

const { STORYBOOK } = process.env || {};

to this:

const STORYBOOK = process.env.STORYBOOK;