TypeError: Cannot read property 'whitelist' of undefined

[StephenEsser]

Summary

With the latest release of postcss-rtl v1.7.0 our application is unable to build. Reverting postcss-rtl to v1.6.0 resolves the issue. I believe the changes in this commit were non-passive. Options were previously optional and are now required.

Stack Trace

ERROR in ./node_modules/terra-dev-site/lib/loader-components/PropsTable.module.scss
Module build failed (from ./node_modules/mini-css-extract-plugin/dist/loader.js):
ModuleBuildError: Module build failed (from ./node_modules/postcss-loader/src/index.js):
TypeError: Cannot read property 'whitelist' of undefined
    at css (/Users/user-name/workspaces/react-on-rails/terra-application/node_modules/postcss-rtl/lib/index.js:37:37)
    at LazyResult.run (/Users/user-name/workspaces/react-on-rails/terra-application/node_modules/postcss/lib/lazy-result.js:295:14)
    at LazyResult.asyncTick (/Users/user-name/workspaces/react-on-rails/terra-application/node_modules/postcss/lib/lazy-result.js:208:26)
    at /Users/user-name/workspaces/react-on-rails/terra-application/node_modules/postcss/lib/lazy-result.js:250:14
    at new Promise (<anonymous>)
    at LazyResult.async (/Users/user-name/workspaces/react-on-rails/terra-application/node_modules/postcss/lib/lazy-result.js:246:23)
    at LazyResult.then (/Users/user-name/workspaces/react-on-rails/terra-application/node_modules/postcss/lib/lazy-result.js:127:17)
    at Promise.resolve.then.then (/Users/user-name/workspaces/react-on-rails/terra-application/node_modules/postcss-loader/src/index.js:142:8)
    at runLoaders (/Users/user-name/workspaces/react-on-rails/terra-application/node_modules/webpack/lib/NormalModule.js:316:20)
    at /Users/user-name/workspaces/react-on-rails/terra-application/node_modules/loader-runner/lib/LoaderRunner.js:367:11
    at /Users/user-name/workspaces/react-on-rails/terra-application/node_modules/loader-runner/lib/LoaderRunner.js:233:18
    at context.callback (/Users/user-name/workspaces/react-on-rails/terra-application/node_modules/loader-runner/lib/LoaderRunner.js:111:13)
    at Promise.resolve.then.then.catch (/Users/user-name/workspaces/react-on-rails/terra-application/node_modules/postcss-loader/src/index.js:208:9)
 @ ./node_modules/terra-dev-site/lib/loader-components/_PropsTable.js 14:47-82
 @ ./src/slide-panel-manager/SlidePanelManager.jsx?dev-site-props-table
 @ ./src/terra-dev-site/doc/application/reference.1/components/SlidePanelManager.doc.mdx
 @ ./dev-site-config/build/contentConfig.js
 @ ./dev-site-config/build/siteConfig.js
 @ ./node_modules/terra-dev-site/lib/TerraDevSite.js

Reproduction Steps

1. Clone this project: https://github.com/cerner/terra-application
2. Run npm install
3. Run npm start
4. Observe the postcss-rtl error thrown

Possible Solution

Revert the changes or default options to an empty object if undefined.

[vkalinichev]

Fixed in 1.7.1

Thanks for report!