Controller fails to pass instance variables into view - ruby-on-rails

Question

In my home page I iterate over collections of objects, and for each object I render its attributes in a table row. There are four collections of objects, defined as instance variables in my controller, all making Guard (according to the used method) raising one of the following errors:
ActionView::Template::Error: undefined method `each_with_index' for nil:NilClass
ActionView::Template::Error: undefined method `any?' for nil:NilClass
The code in my application view raising the above errors is:
<table class="col-md-4 col-md-offset-1">
<thead>
<tr>
<th> Rank </th>
<th> Gamer </th>
<th> Points </th>
</tr>
</thead>
<tbody>
<% #atp_gamers.each_with_index do |gamer, index| %>
<tr>
<td class="index"> <%= index+1 %> </td>
<td class="gamer"> <%= gamer.name %> </td>
<td class="atppoints"> <%= gamer.atpscore %> </td>
</tr>
<% end %>
<tr class="current-user">
<td> <%= #atp_gamers.to_a.index(current_user) + 1 %> </td>
<td> <%= current_user.name %> </td>
<td> <%= current_user.atpscore %> </td>
</tr>
</tbody>
</table>
<table class="col-md-4 col-md-offset-2">
<thead>
<tr>
<th> Year </th>
<th> Champion </th>
<th> Points </th>
</tr>
</thead>
<tbody>
<% if #atp_champions.any? %>
<% #atp_champions.each do |champion| %>
<tr>
<td class="year"> <%= champion.created_at.year %> </td>
<td class="winnername"> <%= champion.name %> </td>
<td class="winnerpoints"> <%= champion.points %> </td>
</tr>
<% end %>
<% end %>
</tbody>
</table>
The above code is part of a partial (named _gamers_home.html.erb) rendered in the original home page:
<% if logged_in? %>
<% if current_user.gamer? %>
<%= render 'static_pages/gamers_home' %>
<% else %>
<%= render 'static_pages/non_gamers_home' %>
<% end %>
<% else %>
<%= render 'static_pages/non_logged_in_home' %>
<% end %>
The logged_in? method is defined as !current_user.nil?
The instance variables that result nil are: #atp_gamers, #wta_gamers, #atp_champions and #wta_champions, defined in the controller as follows:
def home
if logged_in? && !current_user.gamer?
...l
elsif logged_in? && current_user.gamer?
#gamers = User.where(gamer: true)
#atp_gamers = #gamers.order(atpscore: :desc).limit(50)
#wta_gamers = #gamers.order(wtascore: :desc).limit(50)
#atp_champions = AtpChampion.all
#wta_champions = WtaChampion.all
...
end
end
The first instance variable raising the error (each_with_index' for nil:NilClass) is #atp_gamers. In view I tried to change it with its explicit value, that is User.where(gamer: true).order(atpscore: :desc).limit(50), and the respective code is accepted. After this change, Guard raises an error for #atp_champions.
With rails console #atp_gamers and #wta_gamers are not empty, returning 50 records out of 100 users. #atp_champions and #wta_champions are not nil, but empty arrays.
I suspect that this might be an issue raised only by Guard, because the rails server succeeds in rendering the view.

Answer 1

def home
if logged_in? # delete this line
...
end # delete this line
end
Delete the if logged_in?, and see what happens.
Maybe you have to use before_action :logged_in_user, only :home in controller and define the logged_in_user method as private method.
If non-logged-in users also allowed to access the home action, you need to use if statement erb in the view. Like,
<% if logged_in? %>
<% #atp_gamers.each_with_index do |gamer, index| %>
...
<% end %>
--UPDATE--
Maybe, it needs to toss variables to the partial.
Replace
<%= render 'static_pages/gamers_home' %>
to
<%= render partial: 'static_pages/gamers_home', locals: {atg_gamers: #atp_gamers, wta_gamers: #wta_gamers, atp_champions: #atp_champions, wta_champions, #wta_champions} %>
and, replace the #atp_gamers, #wta_gamers, #atp_champions, #wta_champions in the partial to atp_gamers, wta_gamers, atp_champions, wta_champions.
Try and see what happens.