title: Rails 3.2 rake compilation issues
body: <p>Suddenly can't push to Heroku! the error message says:</p>
  
  <blockquote>
    <p>uninitialized constant Haml::Util::Sass</p>
  </blockquote>
  
  <p>(Same exact code and libraries that worked fine until 2 days ago!)</p>
  
  <p>Compilation apparently failing on this line of application.rb:</p>
  
  <pre><code>Bundler.require(*Rails.groups(:assets =&gt; %w(development test)))
  </code></pre>
  
  <p>When compilation is attempted I get this:</p>
  
  <blockquote>
    <p>Could not detect rake tasks    ensure you can run <code>$ bundle exec
    rake -P</code> against your app with no environment variables present    and
    using the production group of your Gemfile.    This may be
    intentional, if you expected rake tasks to be run    cancel the build
    (CTRL+C) and fix the error then commit the fix:    rake aborted!<br>
    uninitialized constant Haml::Util::Sass</p>
  </blockquote>
  
  <p>Full stack trace:</p>
  
  <pre><code>/tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/haml-3.1.6/lib/haml/util.rb:348:in `try_sass'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/haml-3.1.6/lib/sass/rails3_shim.rb:1:in `&lt;top (required)&gt;'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/sass-3.3.2/lib/sass/root.rb:1:in `&lt;top (required)&gt;'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/sass-3.3.2/lib/sass/util.rb:10:in `&lt;top (required)&gt;'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/sass-3.3.2/lib/sass/version.rb:2:in `&lt;top (required)&gt;'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/haml-3.1.6/lib/haml/util.rb:347:in `try_sass'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/haml-3.1.6/lib/sass.rb:6:in `&lt;top (required)&gt;'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/bundler-1.5.2/lib/bundler/runtime.rb:76:in `require'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/bundler-1.5.2/lib/bundler/runtime.rb:76:in `block (2 levels) in require'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
      gems/bundler-1.5.2/lib/bundler/runtime.rb:72:in `each'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
      gems/bundler-1.5.2/lib/bundler/runtime.rb:72:in `block in require'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
      gems/bundler-1.5.2/lib/bundler/runtime.rb:61:in `each'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
      gems/bundler-1.5.2/lib/bundler/runtime.rb:61:in `require'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/bundler-1.5.2/lib/bundler.rb:131:in `require'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/config/application.rb:7:i
  n `&lt;top (required)&gt;'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/Rakefile:5:in `require'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/Rakefile:5:in `&lt;top (requ
  ired)&gt;'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/lib/rake/rake_module.rb:25:in `load'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/lib/rake/rake_module.rb:25:in `load_rakefile'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/lib/rake/application.rb:583:in `raw_load_rakefile'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/lib/rake/application.rb:89:in `block in load_rakefile'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/lib/rake/application.rb:160:in `standard_exception_handling'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/lib/rake/application.rb:88:in `load_rakefile'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/lib/rake/application.rb:72:in `block in run'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/lib/rake/application.rb:160:in `standard_exception_handling'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/lib/rake/application.rb:70:in `run'
         /tmp/build_ae51e5ec-bc73-4105-bce5-33edbe8bee32/vendor/bundle/ruby/1.9.1/
  gems/rake-10.0.3/bin/rake:33:in `&lt;top (required)&gt;'
         vendor/bundle/bin/rake:16:in `load'
  
     vendor/bundle/bin/rake:16:in `&lt;main&gt;'
  -----&gt; WARNINGS:
     Injecting plugin 'rails_log_stdout'
     Injecting plugin 'rails3_serve_static_assets'
     Add 'rails_12factor' gem to your Gemfile to skip plugin injection
     Removing `Gemfile.lock` because it was generated on Windows.
     Bundler will do a full resolve so native gems are handled properly.
     This may result in unexpected gem versions being used in your app.
     In rare occasions Bundler may not be able to resolve your dependencies at all.
     https://devcenter.heroku.com/articles/bundler-windows-gemfile
  -----&gt; Discovering process types
     Procfile declares types -&gt; (none)
     Default types for Ruby  -&gt; console, rake, web, worker
  </code></pre>
  
  <p>GEMFILE:</p>
  
  <pre><code>source 'https://rubygems.org'
  ruby "1.9.3"
  gem 'rails', '3.2.11'
  gem 'useragent'
  gem 'rubyzip', '~&gt; 1.0.0'
  gem 'vpim'
  gem 'ri_cal'
  gem "geocoder"
  gem 'sass'
  gem 'haml', '3.1.6'
  gem 'settingslogic', '~&gt; 2.0.8'
  gem 'devise', '2.1.2'
  gem 'omniauth', '1.1.0'
  gem 'omniauth-facebook', '1.4.1'
  gem 'omniauth-twitter'
  gem 'omniauth-linkedin'
  gem "omniauth-google", "~&gt; 1.0.2"
  gem 'paperclip', '~&gt; 3.3.0'
  gem 'aws-s3', '~&gt; 0.6.3'
  gem 'aws-sdk', '~&gt; 1.6.9'
  gem 'delayed_job_active_record', '0.4.4'
  gem "fb_graph", '2.4.19'
  gem "linkedin"
  gem "twitter"
  gem "nokogiri", "~&gt; 1.5.5"
  gem "gdata", :git=&gt; "https://github.com/agentrock/gdata.git"
  gem 'acts_as_api', "0.4.1"
  gem "rails_admin"
  gem "meta_search", "~&gt; 1.1.3"
  gem "possessive", "~&gt; 1.0.1"
  gem "rake", "10.0.3"
  gem 'newrelic_rpm'
  gem "json", "1.7.7"
  gem "omniauth-google-oauth2"
  gem "google-api-client", :require =&gt; 'google/api_client'
  gem "rest-client", "~&gt; 1.6.7"
  gem "customerio"
  
  group :assets do
    gem 'sass-rails',   '~&gt; 3.2.3'
    gem 'coffee-rails', '~&gt; 3.2.1'
    gem 'uglifier', '&gt;= 1.0.3'
  end
  
  gem 'jquery-rails', '~&gt; 2.1'
  gem 'jquery-ui-rails', '~&gt; 2.0.0'
  gem 'jquery-fileupload-rails','~&gt; 0.3.5'
  
  group :development, :test do
    gem 'rspec-rails', '~&gt; 2.13.0'
    gem 'factory_girl_rails', '4.0.0'
    gem "spork", "~&gt; 0.9.2"
    gem 'hoe', '~&gt; 3.4.0'
  end
  
  group :test do
    gem "shoulda",          "&gt;=3.0.1"
    gem 'shoulda-matchers', "1.4.0"
    gem 'faker'
    gem 'capybara'
    gem 'guard-rspec'
    gem 'launchy'
  end
  
  group :development do
    gem 'sqlite3', '1.3.7'
  end
  
  group :staging, :production do
    gem 'pg', '0.13.2'
  end
  </code></pre>