In order to allow the Sass generators to pick up the default Rails CSS and transform it, we leave it in a standard location for the CSS stylesheet generators to handle. For the simple, default case, just copy it over.
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# File railties/lib/rails/generators/css/scaffold/scaffold_generator.rb, line 9 def copy_stylesheet dir = Rails::Generators::ScaffoldGenerator.source_root file = File.join(dir, "scaffold.css") create_file "app/assets/stylesheets/scaffold.css", File.read(file) end