What is the correct way to handle css preprocessor?

[kendrickw]

How can I incorporate css preprocessor into this plugin? (I'm using packages/rollup).

For example, one of the css imports a stylus sheet (i.e. abc.styl). Can I insert a stylus loader into the plugin, and have it transform the content of abc.styl into css, before having the plugin take over?

[tivac]

If there's a post CSS plugin for stylus you can add that to the before hook to have it transform that file into CSS.

[kendrickw]

There isn't a postcss-stylus, unfortunately. But I suppose I can build one.
For these type of preprocessors (i.e. https://github.com/postcss/sugarss), they are not postcss plugins per se, and the invocation looks like:

 postcss(plugins, { parser: sugarss })

How would something like sugarss fit into the before hook?

[tivac]

Looks like https://github.com/Avol-V/postcss-stylus-parser is a thing that exists, but I don't think I expose a way to define the postcss parser value atm. I'll see what I can do to pipe that in.

[tivac]

Fix published in v21.2.0, you can pass a postcss : { parser : ... } option for parsing custom syntaxes.