<div class="container">

  <div class="artist-header">
    <h1><%=@artist.name%></h1>
    <%= image_tag @artist.avatar.url(:thumb) %>
  </div>

  <div class="row">
    <div class="col s12">
      <ul class="tabs">
        <li class="tab col s3"><a class="active" href="#test1">Collections</a></li>
        <li class="tab col s3 "><a href="#test2">About</a></li>
        <li class="tab col s3"><a href="#test3">Events</a></li>
      </ul>
    </div>
    <div id="test1" class="col s12">
      <ul class="collapsible" data-collapsible="expandable">
        <% @collections.each do |collection| %>
           <li>
             <div class="collapsible-header">
               <%= collection.name %>
             </div>
             <div class="collapsible-body"><p>stuff</p></div>
          </li>
        <% end %>
      </ul>
    </div>
    <div id="test2" class="col s12"> The "about me" info </div>
    <div id="test3" class="col s12"> Come to my show </div>
  </div>

  <% if current_user && current_user.id == @artist.id %>
    <div class="add-collection">
      <a href="<%=new_user_collection_path(@artist.id)%>">Add a Collection</a>
    </div>
  <% end %>

</div>

<div class="container">

  <div class="artist-header">
    <h1><%=@artist.name%></h1>
    <%= image_tag @artist.avatar.url(:thumb) %>
  </div>

  <div class="row">
    <div class="col s12">
      <ul class="tabs">
        <li class="tab col s3"><a class="active" href="#test1">Collections</a></li>
        <li class="tab col s3 "><a href="#test2">About</a></li>
        <li class="tab col s3"><a href="#test3">Events</a></li>
      </ul>
    </div>
    <div id="test1" class="col s12">
      <ul class="collapsible" data-collapsible="expandable">
        <% if @collections && @collections.each do |collection| %>
           <li>
             <div class="collapsible-header">
               <%= collection.name %>
             </div>
             <div class="collapsible-body"><p>stuff</p></div>
          </li>
        <% end %>
      </ul>
    </div>
    <div id="test2" class="col s12"> The "about me" info </div>
    <div id="test3" class="col s12"> Come to my show </div>
  </div>

  <% if current_user && current_user.id == @artist.id %>
    <div class="add-collection">
      <a href="<%=new_user_collection_path(@artist.id)%>">Add a Collection</a>
    </div>
  <% end %>

</div>

Add fallback for artist having no collections to prevent an error
Add fallback for artist having no collections to prevent an error
