Make missing asset digest an error

Author: jwhitley

lib/requirejs/error.rb

@@ -3,4 +3,6 @@ module Requirejs
   class MultipleIncludeError < RuntimeError; end
   # Raised if the configuration fails validation.
   class ConfigError < ArgumentError; end
+  # Raised if the builder encounters an error.
+  class BuildError < RuntimeError; end
 end

lib/requirejs/rails/builder.rb

@@ -19,7 +19,7 @@ def digest_for(path)
       if !Rails.application.assets.file_digest(path).nil?
         Rails.application.assets.file_digest(path).hexdigest
       else
-        puts "Asset digest not found:", path
+        raise Requirejs::BuildError, "Cannot compute digest for missing asset: #{path}"
       end
     end