title: Phusion error: undefined method `has?' for Sass::Util:Module
body: <p>I get the following error issued by Phusion when loading a web page:</p>
  
  <pre><code>There was an error while trying to load the gem 'compass-rails'.
  Gem Load Error is: undefined method `has?' for Sass::Util:Module
  Did you mean?  hash
                 Hash
  Backtrace for gem load error is:
  /Volumes/Data/htdocs/zetcho/vendor/bundle/gems/compass-0.12.2/lib/compass/sass_extensions/functions/urls.rb:5:in `has?'
  </code></pre>
  
  <p>The code at the indicated location is: </p>
  
  <pre><code>module Compass::SassExtensions::Functions::Urls
  
  
  def self.has?(base, instance_method)
    Sass::Util.has?(:instance_method, base, instance_method)
  end
  </code></pre>
  
  <p>My gem file contains:</p>
  
  <pre><code># Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
  gem 'rails', '~&gt; 5.1.2'
  
  # Use mysql as the database for Active Record
  gem 'mysql2', '~&gt; 0.3.18'
  
  # Use SCSS for stylesheets
  gem 'sass-rails', '~&gt; 5.0'
  
  # Use Compass for stylesheets
  gem 'compass-rails'
  
  # Use the Compass extension susy
  gem "sprockets"
  gem 'susy'
  </code></pre>
  
  <p>I've just created the Ruby on Rails site using Rails 5.1.2 and ruby 2.3.1. I have a much older site that works fine with the gem. Did I miss a step in the overall install or is this a bug with compass-rails?</p>
  
  <p>I got the same error when I tried to add a controller:</p>
  
  <pre><code>rails generate controller home index
  </code></pre>