Angular 6 到 12 迁移问题

Question

I am getting below error after i upgraded from Angular 6 to Angular 12

styles.css - Error: styles.css from Css Minimizer
Error: [object Object] is not a PostCSS plugin
    at Processor.normalize (C:\xxxxx\xxxxx\node_modules\postcss\lib\processor.js:168:15)

Can anyone help me what can be reason for this?

Answer 1

Looks like the Processor can't make sense of the Object being passed to it. I just recently had something very similar from a migration as well so might suspect some version mismatch. For my case the problem was caused by old package_lock.

Just the get this out of the way. Remove packacge-lock and node_modules rm -rf node_modules package-lock.json , add compatible postcss and install other packages as well npm install -D postcss && npm install .

You could also go over some migration steps so see if you missed something. https://update.angular.io/?l=3&v=6.0-12.0