Sprockets 3.x find_asset replacement

find_asset_replacement.rb

# In Sprockets 2.x, you used to be able to find the location of an uncompiled asset by doing:
Rails.application.assets.find_asset(path)

# However, in Sprockets 3.x, `assets` is nil, `find_asset` isn't accessible without creating
# your own Sprockets::Manifest object, and there's no direct equivalent. The officially
# supported method is to use:
Rails.application.assets_manifest.assets[path]

# However, this only searches for *already compiled* assets.
# 
# My use case: To embed fonts in a CSS file, I needed to find the path for
# fonts at precompile time, where the assets_manifest was effectively empty.
# Asset searching was relatively complicated because of the font-awesome gem
# and an in-house Engine which both had their own fonts.
# 
# The solution: Basically fuck sprockets and do asset resolution yourself.

locations = Rails.application.config.assets[:paths]
locations.each do |location|
  resolved_path = File.join(location, path)
  if File.exists?(resolved_path)
    return resolved_path
  end
end

# Conclusion: Fuck sprockets