Merge pull request rails#6423 from lest/patch-2

assets: don't add extension if other given and file exists

Author: carlosantoniodasilva

actionpack/lib/sprockets/helpers/rails_helper.rb

@@ -155,8 +155,13 @@ def rewrite_asset_path(source, dir, options = {})
         end
 
         def rewrite_extension(source, dir, ext)
-          if ext && File.extname(source) != ".#{ext}"
-            "#{source}.#{ext}"
+          source_ext = File.extname(source)
+          if ext && source_ext != ".#{ext}"
+            if !source_ext.empty? && asset_environment[source]
+              source
+            else
+              "#{source}.#{ext}"
+            end
           else
             source
           end

actionpack/test/fixtures/sprockets/app/stylesheets/style.ext

@@ -307,6 +307,9 @@ def compute_host(source, request, options = {})
     assert_match %r{\A<link href="/assets/style-[0-9a-f]+.css" media="screen" rel="stylesheet" type="text/css" />\Z},
       stylesheet_link_tag("style", "style")
 
+    assert_match %r{\A<link href="/assets/style-[0-9a-f]+.ext" media="screen" rel="stylesheet" type="text/css" />\Z},
+      stylesheet_link_tag("style.ext")
+
     @config.assets.compile = true
     @config.assets.debug = true
     assert_match %r{<link href="/stylesheets/application.css" media="screen" rel="stylesheet" type="text/css" />},