commit 47330714ddfdd0f1299830eaa136bdb3bf184004
Author: Andreas Jacobsen <andreaja@ifi.uio.no>
Date:   Fri Sep 5 14:03:36 2008 +0200

    Solves http://rails.lighthouseapp.com/projects/8994/tickets/440-windows-file-loading

diff --git a/actionpack/lib/action_view/helpers/asset_tag_helper.rb b/actionpack/lib/action_view/helpers/asset_tag_helper.rb
index ed33f08..9177dc1 100644
--- a/actionpack/lib/action_view/helpers/asset_tag_helper.rb
+++ b/actionpack/lib/action_view/helpers/asset_tag_helper.rb
@@ -485,7 +485,7 @@ module ActionView
 
           source = COMPUTED_PUBLIC_PATHS.fetch(cache_key) do
             begin
-              source += ".#{ext}" if ext && File.extname(source).blank? || File.exist?(File.join(ASSETS_DIR, dir, "#{source}.#{ext}"))
+              source += ".#{ext}" if (ext && File.extname(source).blank?) || (ext && File.exist?(File.join(ASSETS_DIR, dir, "#{source}.#{ext}")))
 
               if source =~ %r{^[-a-z]+://}
                 source