PostCSS error in version 0.15.8

[kirill-konshin]

This issue is a: Bug Report

• Bug report
• Feature request
• Question / support request
• Other

Got the following error for any given css file after upgrade to 0.15.8 from 0.15.6:

Module build failed: TypeError: Cannot read property 'postcss' of null
    at Processor.normalize (/Users/xxx/node_modules/postcss/lib/processor.js:136:12)
    at new Processor (/Users/xxx/node_modules/postcss/lib/processor.js:51:25)
    at postcss (/Users/xxx/node_modules/postcss/lib/postcss.js:73:10)
    at /Users/xxx/node_modules/postcss-loader/index.js:122:16
    at process._tickCallback (internal/process/next_tick.js:103:7)

[insin]

I also hit this while working on v0.15.8, but the Webpack version bump in the release fixed it for me.

Have you tried a re-install of your node_modules if you're using npm3? Non-determinism!

[kirill-konshin]

Yes, I did removed node_modules and made complete reinstall.

[kirill-konshin]

I am using NPM version 4.3.0. Webpack version is 2.6.1. I have also upgraded nwb-sass to 0.8.0 but the issue persists.

[insin]

Do you have a repo I can use to reproduce this locally?

[kirill-konshin]

After long debug I have figured that the issue occurs because of CSS import from SCSS file:

@import "~react-datetime/css/react-datetime.css";

.rdt {
    // stuff
}

Surprisingly, it works w/o extension:

@import "~react-datetime/css/react-datetime";

As I said, it used to work with 0.15.6.

[insin]

Every loader involved in handling styles had a major version bump since 0.15.x so I'll trawl the changelogs and issues to see if anything sticks out.

[alexander-akait]

Related to css-loader and postcss-loader(little) webpack-contrib/postcss-loader#234 (comment)

[tnrich]

I'm also hitting this issue with the latest nwb v0.16.3
Thanks for the hard work @insin :)

[insin]

Thanks for the investigation @evilebottnawi

[tnrich]

@insin any update on this? None of the newer versions work for me..
Here is the offending line of css:
@import url(~@blueprintjs/core/dist/blueprint.css);

[insin]

Does anyone have a sample repo I can use to reproduce this?

[tnrich]

I think a simple one would be the base nwb setup for a react component plus yarn install @blueprint/core and then in the demo/index.js file have a require of @import url(~@blueprintjs/core/dist/blueprint.css);

[insin]

According to webpack-contrib/postcss-loader#258, ident is needed again for postcss config to work.

nwb no longer adds this as I thought recent versions of Webpack automatically handled passing options properly, but I guess not, as @import url(~@blueprintjs/core/dist/blueprint.css); works once I add an ident to postcss-loader's options.

[tnrich]

Thank you!!

[insin]

Fix released in:

• v0.17.3 (default version) - Webpack 2, works in npm2 if you're stuck on it
• v0.18.4 (nwb@next) - Webpack 3, updated dependencies, new features, doesn't work in npm2 yet due to Webpack plugin peerDependencies)