From the documentation:
"By default, and for security, web code documents are excluded from file displays. If you have a directory or attachment page with some code docs that you want to include in your display, you can choose to include them along with any/all other file types. Code file types excluded by default are: js, pl, py, rb, css, less, scss, sass, php, htm, html, cgi, asp, cfm, cpp, xml, yml, shtm, xhtm, java, class. The one exception is index.htm/l and index.php files, which are always excluded, and will not be included if Code Docs are enabled."
[fileaway code="yes"]