Can't upgrade to newer govuk_publishing_components
kevindew opened this issue · 2 comments
There are regular PR's coming through for each govuk_publishing_components update and failing. For example: #4723. @alex-ju and I spent a while looking at the problem and this catalogues our results.
These are failing since the introduction of the following code on govuk-frontend: @supports (margin: unquote("max(calc(0px))")) { and this only fails on production asset:precompile not development.
Our theory is that the SCSS is effectively processed twice. Once to build the scss file and a second time to compress them. At the second pass of the file the unquote has been removed and thus SCSS is treating max as a sass function rather than a CSS function.
We saw this debugging the sassc-rails compressor (https://github.com/sass/sassc-rails/blob/master/lib/sassc/rails/compressor.rb#L24-L29) and putting in a byebug had the following results:
Given an input of:
p {
padding-right: unquote("max(calc(0px))");
}
an output of:
[20, 29] in /Users/kevindew/.rbenv/versions/2.6.1/lib/ruby/gems/2.6.0/gems/sassc-rails-2.1.0/lib/sassc/rails/compressor.rb
20: else
21: args[0][:data] #sprockets 3.x
22: end
23: require "byebug"; byebug # DEBUG @kevindew
24:
=> 25: SassC::Engine.new(
26: input,
27: {
28: style: :compressed
29: }
(byebug) input
"/* line 1, app/assets/stylesheets/application.scss */\np {\n padding-right: max(calc(0px));\n}\n"
(byebug) c
rake aborted!
SassC::SyntaxError: Error: "calc(0px)" is not a number for `max'
on line 3 of stdin, in function `max`
from line 3 of stdin
>> padding-right: max(calc(0px));
similar problem in finder-frontend