TypeError: Cannot read property 'stringify' of undefined (8.3.0 -> 8.4.16)

I faced an issue with upgrading my Nx codebase (React+StyledComponents) to the latrst version. The change I noticed is that version goes up 8.3.0 -> 8.4.16 I do not have working small reproduction, if you think you will need it can you explain what sample will satisfy your needs (complexity)

My assumption here is that now this module cannot handle empty files or files without styled components

 $) stylelint "**/*.{ts,tsx}"

TypeError: Cannot read property 'stringify' of undefined
    at Function.stringify (D:\sources\rmboa\node_modules\postcss-syntax\stringify.js:8:38)
    at MapGenerator.generate (D:\sources\rmboa\node_modules\stylelint\node_modules\postcss\lib\map-generator.js:323:12)
    at LazyResult.stringify (D:\sources\rmboa\node_modules\stylelint\node_modules\postcss\lib\lazy-result.js:277:20)
    at LazyResult.runAsync (D:\sources\rmboa\node_modules\stylelint\node_modules\postcss\lib\lazy-result.js:443:17)
    at LazyResult.async (D:\sources\rmboa\node_modules\stylelint\node_modules\postcss\lib\lazy-result.js:221:30)
    at LazyResult.then (D:\sources\rmboa\node_modules\stylelint\node_modules\postcss\lib\lazy-result.js:206:17)

[omjokine]

I have this same issue. Unfortunately I don’t have very simple piece of code to reproduce this issue, but got the same stack trace as OP had.

This happened when updated postcss from 8.4.14 to 8.4.16. So I can reproduce it simply running npm update postcss and then running stylelint. So I guess it is regression in postcss, not in stylelint.

[ai]

Seems like postcss-syntax is hack the AST.

We can’t just remove node.type === 'root' because it is fixed another bug.

Here are my suggestions:

1. Fix Stylelint and set .source.syntax.stringify to some custom analog of docStringify
2. Find a way to detect Document from postcss-syntax and avoid conversation. But I afraid it will break AST normalization fix.