Don't include the context in the importer

[bhollis]

Sass 3.3 attempts to marshal the importer, resulting in messages like:

Warning. Error encountered while saving cache ./.sass-cache/6d19918aae9b194893adf3de06101cc3ab87507f/_partial2.css.sassc: can't dump anonymous class #<Class:0x007fb885d0a030>

I opened an issue with Sass (nex3/sass#1196) and they said to just make sure the importer is marshal-able, which in this case means not holding a reference to the context. See sstephenson/sprockets#542 for what they had to do.

[petebrowne]

I'm digging through this now and having a bit of trouble. Their solution was to drop the Importer altogether, which removes quite a bit of functionality.

The timeframe for this might be slow, I could use some help if you have the time

[petebrowne]

From what I can tell:

It's necessary that we associate and importer with each source range in order to properly generate source maps. Importers have specific logic about the URIs that should be included in a source map, and we need to access that logic when generating source maps.

Source maps aren't even a supported feature of Sprockets::Sass and would take quite a lot of black magic to support: sass-rails-source-maps.

Is the warning output the only issue you've seen related to this?

[petebrowne]

I've got a branch: sass-3.3 where I'm testing out removing the Importer. There are a few features sprockets-sass will lose as a result.

• Glob Imports - could be handled by sass-globbing
• Sprockets Processing on imported files - can no longer import files named "dep.css.scss" or do ERB pre-processing

What do you think? Are these features being used by middleman?

[bhollis]

Thanks for taking a look.

I'm not sure about those features - for example, importing other files seems pretty important, or am I missing something about that? Globs I'm not as interested in, but I'm sure our users use them all over the place.

I'm also interested in actually supporting source maps at some point, so anything that closed that off is a bummer too.

I wonder if there's a way to actually marshal the importer by implementing custom dump/load methods?

[petebrowne]

I'm going to try @nex3's suggestion this weekend. Didn't realize you get the context from the options. Hopefully I'll have a fix here soon

[bhollis]

Awesome, thanks for working on this.

[petebrowne]

Just pushed 1.1.0 which fixes this problem! Let me know how this works for you

There are several improvements I can make to the Importer to make it even more Sass 3.3 compatible.