This PR is a major change to Sass compilation in Discourse.
The new version of sass-ruby moves to dart-sass putting we back on the supported version of Sass. It does so while keeping compatibility with the existing method signatures, so minimal change is needed in Discourse for this change.
This moves us
From:
- sassc 2.0.1 (Feb 2019)
- libsass 3.5.2 (May 2018)
To:
- dart-sass 1.58
This update applies the following breaking changes:
>
> These breaking changes are coming soon or have recently been released:
>
> [Functions are stricter about which units they allow](https://sass-lang.com/documentation/breaking-changes/function-units) beginning in Dart Sass 1.32.0.
>
> [Selectors with invalid combinators are invalid](https://sass-lang.com/documentation/breaking-changes/bogus-combinators) beginning in Dart Sass 1.54.0.
>
> [/ is changing from a division operation to a list separator](https://sass-lang.com/documentation/breaking-changes/slash-div) beginning in Dart Sass 1.33.0.
>
> [Parsing the special syntax of @-moz-document will be invalid](https://sass-lang.com/documentation/breaking-changes/moz-document) beginning in Dart Sass 1.7.2.
>
> [Compound selectors could not be extended](https://sass-lang.com/documentation/breaking-changes/extend-compound) in Dart Sass 1.0.0 and Ruby Sass 4.0.0.
SCSS files have been migrated automatically using `sass-migrator division app/assets/stylesheets/**/*.scss`
We've had a couple of problems with the R2 gem where it generated a broken RTL CSS bundle that caused a badly broken layout when Discourse is used in an RTL language, see a3ce93b and 5926386. For this reason, we're replacing R2 with `rtlcss` that can handle modern CSS features better than R2 does.
`rltcss` is written in JS and available as an npm package. Calling the `rltcss` from rubyland is done via the `rtlcss_wrapper` gem which contains a distributable copy of the `rtlcss` package and loads/calls it with Mini Racer. See https://github.com/discourse/rtlcss_wrapper for more details.
Internal topic: t/76263.
This PR introduces a new hidden site setting that allows admins to display a splash screen while site assets load.
The splash screen can be enabled via the `splash_screen` hidden site setting.
This is what the splash screen currently looks like
5ceb72f085.mp4
Once site assets load, the splash screen is automatically removed.
To control the loading text that shows in the splash screen, you can change the preloader_text translation string in admin > customize > text
It's very easy to forget to add `require 'rails_helper'` at the top of every core/plugin spec file, and omissions can cause some very confusing/sporadic errors.
By setting this flag in `.rspec`, we can remove the need for `require 'rails_helper'` entirely.
