Merge pull request #75 from readthedocs/davidfischer/async-js-improvements

Make JS async where possible

Author: ericholscher

readthedocs_ext/_templates/readthedocs-insert.html.tmpl

@@ -28,6 +28,6 @@ READTHEDOCS_DATA['source_suffix'] = {{ page_source_suffix|tojson }}
 {%- endif %}
 </script>
 
-<script type="text/javascript" src="{{ rtd_analytics_url }}"></script>
+<script type="text/javascript" src="{{ rtd_analytics_url }}" async="async"></script>
 
 <!-- end RTD <extrahead> -->

readthedocs_ext/readthedocs.py

@@ -65,7 +65,8 @@ def finalize_media(app):
     if sphinx.version_info < (1, 8):
         app.builder.script_files.append(js_file)
     else:
-        app.add_js_file(js_file)
+        kwargs = {'async': 'async'}     # Workaround reserved word in Py3.7
+        app.add_js_file(js_file, **kwargs)
 
 
 def update_body(app, pagename, templatename, context, doctree):