app/views/exercises/_list_single.html.erb
<%= link_to exercise.name, exercise %>
<%
notes = []
notes << 'hidden' if exercise.hidden?
notes << 'expired' if exercise.expired_for?(current_user)
notes << 'locked' unless defined?(unlocks) ? (!exercise.requires_unlock? || unlocks.include?(exercise.name)) : exercise.unlocked_for?(current_user, false)
notes << 'disabled' if exercise.disabled?
%>
<% unless notes.empty? %>
(<%= notes.join(', ') %>)
<% end %>