title: Rails won't precompile .js.erb
body: <p>Why Rails won't precompile a <code>.js.erb</code> asset?</p>
  
  <p>My <code>config/application.rb</code>:</p>
  
  <pre><code>require File.expand_path('../boot', __FILE__)
  
  require 'rails/all'
  
  Bundler.require(:default, Rails.env)
  
  module Sflitmap
    class Application &lt; Rails::Application
      # these precompile OK
      config.assets.precompile += ['edge/edge.1.5.0.min.js', 'edge/ink-falling_edgeActions.js', 'edge/inkAnimationTrigger.js']
  
      # this will not precompile
      config.assets.precompile += ['edge/ink-falling_edge.js.erb']
    end
  end
  </code></pre>
  
  <p>My <code>config/environments/production.rb</code>:</p>
  
  <pre><code>Sflitmap::Application.configure do
    # Settings specified here will take precedence over those in config/application.rb.
  
    # Code is not reloaded between requests.
    config.cache_classes = true
  
    # Eager load code on boot. This eager loads most of Rails and
    # your application in memory, allowing both thread web servers
    # and those relying on copy on write to perform better.
    # Rake tasks automatically ignore this option for performance.
    config.eager_load = true
  
    # Full error reports are disabled and caching is turned on.
    config.consider_all_requests_local       = false
    config.action_controller.perform_caching = true
  
    # Enable Rack::Cache to put a simple HTTP cache in front of your application
    # Add `rack-cache` to your Gemfile before enabling this.
    # For large-scale production use, consider using a caching reverse proxy like nginx, varnish or squid.
    # config.action_dispatch.rack_cache = true
  
    # Disable Rails's static asset server (Apache or nginx will already do this).
    config.serve_static_assets = false
  
    # Compress JavaScripts and CSS.
    config.assets.js_compressor = :uglifier
    # config.assets.css_compressor = :sass
  
    # Do not fallback to assets pipeline if a precompiled asset is missed.
    config.assets.compile = false
  
    # Generate digests for assets URLs.
    config.assets.digest = true
  
    # Version of your assets, change this if you want to expire all your assets.
    config.assets.version = '1.0'
  
    # Specifies the header that your server uses for sending files.
    # config.action_dispatch.x_sendfile_header = "X-Sendfile" # for apache
    # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for nginx
  
    # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
    # config.force_ssl = true
  
    # Set to :debug to see everything in the log.
    config.log_level = :info
  
    # Prepend all log lines with the following tags.
    # config.log_tags = [ :subdomain, :uuid ]
  
    # Use a different logger for distributed setups.
    # config.logger = ActiveSupport::TaggedLogging.new(SyslogLogger.new)
  
    # Use a different cache store in production.
    # config.cache_store = :mem_cache_store
  
    # Enable serving of images, stylesheets, and JavaScripts from an asset server.
    # config.action_controller.asset_host = "http://assets.example.com"
  
    config.assets.paths &lt;&lt; Rails.root.join('app', 'assets', 'fonts')
  
    # Precompile additional assets.
    # application.js, application.css, and all non-JS/CSS in app/assets folder are already added.
    # config.assets.precompile += %w( search.js )
    config.assets.precompile += %w( .svg .eot .woff .ttf )
  
    # Ignore bad email addresses and do not raise email delivery errors.
    # Set this to true and configure the email server for immediate delivery to raise delivery errors.
    # config.action_mailer.raise_delivery_errors = false
  
    # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
    # the I18n.default_locale when a translation can not be found).
    config.i18n.fallbacks = true
  
    # Send deprecation notices to registered listeners.
    config.active_support.deprecation = :notify
  
    # Disable automatic flushing of the log to improve performance.
    # config.autoflush_log = false
  
    # Use default logging formatter so that PID and timestamp are not suppressed.
    config.log_formatter = ::Logger::Formatter.new
  end
  </code></pre>
  
  <p>When I run <code>RAILS_ENV=production rake assets:precompile</code> I get:</p>
  
  <pre><code>- public
  -- assets
  --- edge
  ---- edge.1.5.0.min-610ab04bb1d4d0ad9a2a845821f04bdf.js
  ---- edge.1.5.0.min-610ab04bb1d4d0ad9a2a845821f04bdf.js.gz
  ---- ink-falling_edgeActions-9bdaa1845a29b15bd2562058432de721.js
  ---- ink-falling_edgeActions-9bdaa1845a29b15bd2562058432de721.js.gz
  ---- inkAnimationTrigger-3c35d0b73061bb5de0e691d694925902.js
  ---- inkAnimationTrigger-3c35d0b73061bb5de0e691d694925902.js.gz
  </code></pre>
  
  <p>Why won't <code>ink-falling_edge-....js</code> precompile?</p>
  
  <p>I'm using <code>ruby "2.0.0"</code> and <code>gem 'rails', '4.0.0'</code></p>