Why does rake assets:precompile produce an empty css stylesheet? - css

Question

I'm using sass-rails and haml-rails gems, so that I can write css file in HAML-sass style.
The thing is when I want to go for production and precompile my stylesheet, the command rake assets:precompile run without error but the generated application.css is empty.
Here it is my Gemfile :
source 'https://rubygems.org'
gem 'rails', '~>3.2'
gem 'pg', '>= 0.14'
gem 'haml-rails' #, '~> 0.3'
group :development, :test do
gem 'factory_girl_rails'
end
group :developpement do
gem 'rspec-rails', '>= 2.11'
gem 'capistrano', '>= 2.12'
gem 'faker', '>= 1.0'
gem 'rvm-capistrano'
end
group :test do
gem 'rspec', '>= 2.11'
gem 'webrat', '>= 0.7'
gem 'spork-rails', '>= 3.2'
end
group :assets do
gem 'sass-rails', '>= 3.2.3'
gem 'coffee-rails', '>= 3.2.1'
gem 'compass-rails', '>= 1.0'
gem 'execjs'
gem 'therubyracer', :platforms => :ruby
gem 'uglifier', '>= 1.0.3'
end
gem 'jquery-rails'
gem 'annotate'
gem 'excel_rails' #, '~> 0.3'
gem 'spreadsheet' #, '~> 0.7'
gem "schema_plus", :git => "git://github.com/lomba/schema_plus.git"
gem 'ar-octopus' #, '~> 0.3'
gem 'squeel' #, '~> 1.0'
gem 'devise' #, '~> 2.1'
gem 'role_model'
gem 'declarative_authorization'
gem 'rails-translate-routes' #, '~> 0.1'
gem 'validates_timeliness' #, '~> 3.0'
Here it is my (empty) app/assets/stylesheets/application.css.sass
/*
* This is a manifest file that'll be compiled into application.css, which will include all the files
* listed below.
*
* Any CSS and SCSS file within this directory, lib/assets/stylesheets, vendor/assets/stylesheets,
* or vendor/assets/stylesheets of plugins, if any, can be referenced here using a relative path.
*
* You're free to add application-wide styles to this file and they'll appear at the top of the
* compiled file, but it's generally better to create a new file per style scope.
*
*/
I removed the following commented lines as per recommandation on https://github.com/rails/sass-rails :
*= require_self
*= require_tree .
my css.sass files are stored here :
app/assets/stylesheets/screen.css.sass
app/assets/stylesheets/partials/ (many partials files _*.css.sass referenced by screen.css.sass)
=== UPDATE ===
Please note I'm using COMPASS gem. So mixin and variables need to be shared between stylesheets.
Just in case, this is my app/assets/stylsheets/screen.css.sass file :
// This import applies a global reset to any page that imports this stylesheet.
#import blueprint/reset
// To configure blueprint, edit the partials/base.sass file.
#import partials/base
#import blueprint/interaction
#import blueprint/typography
#import blueprint/grid
#import blueprint/buttons
#import blueprint/utilities
#import compass/layout/grid-background
#import compass/typography/lists/inline-block-list
#import compass/typography/lists/horizontal-list
#import compass/utilities/general/float
#import compass/css3/border-radius
#import compass/css3/box-shadow
#import compass/css3/text-shadow
#import compass/css3/transition
#import partials/opf_mixins_et_functions
#import partials/link_icons
#import partials/typo
#import partials/application
#import partials/affichage_donnees
#import partials/tableau_edition
#import partials/page
#import partials/form
#import partials/feedback
=== UPDATE 2 ===
I realized that my Gemfile will lead me to trouble in production because I put the following Gems in the assets group :
group :assets do
...
gem 'execjs'
gem 'therubyracer', :platforms => :ruby
...
end
Because Production environnement as well needs a javascript interpreter...
So I will move them outside of any group in my Gemfile.
Any advice welcome

Answer 1

You're recommended to remove those two lines but you still need to include yourself your files :
*= require screen
*= require_dir partials/
Do note something, however : this doesn't work like #import - you won't get your mixins and variable shared. Use a real #import for that

Answer 2

OK I solved it with the following solution :
Following the spirit of the last answer, it appears that adding the following line at the end of my /app/assets/styelsheets/application.css.sass solved my issue :
#import screen
Every referenced partial stylesheet by screen.css.sass will then be automatically imported.

Answer 3

My precompiled assets (application.js and application.css) were empty ...
What solved the problem for me :
set the last rails version in Gemfile (3.2.14 for now)
bundle update
bundle install
restart the app touch tmp/restart.txt