Load previous and next issue links asynchronously

app/overrides/issues/_action_menu_edit.rb

@@ -1,44 +1,4 @@
-Deface::Override.new :virtual_path  => 'issues/_action_menu_edit',
-                     :name          => 'prevents-render-edit-partial-render-it-only-on-edit-button-click',
-                     :replace       => "erb[loud]:contains(\"render :partial => 'edit'\")",
-                     :text          => <<-RENDER_PARTIAL
-<% unless Setting.plugin_redmine_tiny_features.key?('load_issue_edit_form_asynchronously') %>
-  <%= render :partial => 'edit' %>
-<% else %>
-  <%# These header tags are not included if the partial is not preloaded %>
-  <% content_for :header_tags do %>
-    <%= javascript_include_tag 'attachments' %>
-  <% end %>
-  <script>
-    function loadIssueEditForm(id){
-      if ($('#issue-form').length < 1) {
-        $.ajax({
-          url: "<%= render_form_by_ajax_path(@issue.id) %>",
-          beforeSend: function(){
-            $('#ajax-indicator').addClass('bottom');
-          },
-          success: function(response) {
-            $('#ajax-indicator').removeClass('bottom');
-            if(response){
-              $('#update').append(response.html);
-              $(document).ready(function() {
-                // for datepicker element,
-                <% include_calendar_headers_tags %>
-                // for wikitoolbar element in mode Textile,
-                setupFileDrop();
-                // But for mode visual there is no need to call because it is already called in { $(document).ajaxSuccess/redmine_wysiwyg_editor }
-              });
-            }
-          },error: function(response) {
-            $('#ajax-indicator').removeClass('bottom');
-            console.error(response);
-          },
-        });
-      }
-    }
-    $(document).ready(function() {
-      loadIssueEditForm();
-    });
-  </script>
-<% end %>
-RENDER_PARTIAL
+Deface::Override.new :virtual_path => 'issues/_action_menu_edit',
+                     :name         => 'load-edit-partial-asynchronously',
+                     :replace      => "erb[loud]:contains(\"render :partial => 'edit'\")",
+                     :partial      => 'issues/load_issue_show_asynchronously'

app/views/issues/_load_issue_show_asynchronously.html.erb

@@ -0,0 +1,54 @@
+<% if Setting.plugin_redmine_tiny_features.key?('load_issue_edit_form_asynchronously') == false %>
+  <%= render :partial => 'edit' %>
+<% else %>
+  <%# These header tags are not included if the partial is not preloaded %>
+  <% content_for :header_tags do %>
+    <%= javascript_include_tag 'attachments' %>
+  <% end %>
+  <script>
+      function loadIssueEditForm() {
+          if ($('#issue-form').length < 1) {
+              $.ajax({
+                  url: "<%= render_form_by_ajax_path(@issue.id) %>",
+                  beforeSend: function () {
+                      $('#ajax-indicator').addClass('bottom');
+                  },
+                  success: function (response) {
+                      $('#ajax-indicator').removeClass('bottom');
+                      if (response) {
+                          $('#update').append(response.html);
+                          $(document).ready(function () {
+                              // for datepicker element,
+                              <% include_calendar_headers_tags %>
+                              // for wikitoolbar element in mode Textile,
+                              setupFileDrop();
+                              // But for mode visual there is no need to call because it is already called in { $(document).ajaxSuccess/redmine_wysiwyg_editor }
+                          });
+                      }
+                  }, error: function (response) {
+                      $('#ajax-indicator').removeClass('bottom');
+                      console.error(response);
+                  },
+              });
+          }
+      }
+
+      function loadPreviousAndNextIssueIds() {
+          $.ajax({
+              url: "<%= load_previous_and_next_issue_ids_path(@issue.id) %>",
+              success: function (response) {
+                  if (response) {
+                      $('.issue.details').prepend(response.html);
+                  }
+              }, error: function (response) {
+                  console.error(response);
+              },
+          });
+      }
+
+      $(document).ready(function () {
+          loadIssueEditForm();
+          loadPreviousAndNextIssueIds();
+      });
+  </script>
+<% end %>

app/views/issues/_previous_and_next_issue_ids.html.erb

@@ -0,0 +1,24 @@
+<%# Standard Redmine code copied from issues/show.html.erb %>
+<%# Must be updated if standard code is updated %>
+
+<% if @prev_issue_id || @next_issue_id %>
+  <div class="next-prev-links contextual">
+    <%= link_to_if @prev_issue_id,
+                   "\xc2\xab #{l(:label_previous)}",
+                   (@prev_issue_id ? issue_path(@prev_issue_id) : nil),
+                   :title => "##{@prev_issue_id}",
+                   :accesskey => accesskey(:previous) %> |
+    <% if @issue_position && @issue_count %>
+        <span class="position">
+          <%= link_to_if @query_path,
+                         l(:label_item_position, :position => @issue_position, :count => @issue_count),
+                         @query_path %>
+        </span> |
+    <% end %>
+    <%= link_to_if @next_issue_id,
+                   "#{l(:label_next)} \xc2\xbb",
+                   (@next_issue_id ? issue_path(@next_issue_id) : nil),
+                   :title => "##{@next_issue_id}",
+                   :accesskey => accesskey(:next) %>
+  </div>
+<% end %>

config/routes.rb

@@ -1,8 +1,9 @@
 resources :projects do
   put :custom_field_enumerations, :controller => 'project_custom_field_enumerations', action: 'update', as: 'update_custom_field_enumerations'
 end
-match 'issues/render_form_by_ajax/:id', :controller => 'issues', :action => 'render_form_by_ajax', :via => :get,  :as => 'render_form_by_ajax'
-match 'queries/author_values_pagination', :controller => 'queries', :action => 'author_values_pagination' , :via => :get,  :as => 'author_values_pagination'
-match 'queries/assigned_to_values_pagination', :controller => 'queries', :action => 'assigned_to_values_pagination' , :via => :get,  :as => 'assigned_to_values_pagination'
+get 'issues/render_form_by_ajax/:id', :controller => 'issues', :action => 'render_form_by_ajax', :as => 'render_form_by_ajax'
+get 'issues/load_previous_and_next_issue_ids/:id', to: 'issues#load_previous_and_next_issue_ids', as: :load_previous_and_next_issue_ids
+get 'queries/author_values_pagination', :controller => 'queries', :action => 'author_values_pagination', :as => 'author_values_pagination'
+get 'queries/assigned_to_values_pagination', :controller => 'queries', :action => 'assigned_to_values_pagination', :as => 'assigned_to_values_pagination'
 
 post 'issues/switch', to: 'issues#switch_display_mode', as: :switch_display_mode

lib/redmine_tiny_features/issues_controller_patch.rb

@@ -2,12 +2,23 @@
 
 module RedmineTinyFeatures::IssuesControllerPatch
 
+  def retrieve_previous_and_next_issue_ids(force_load = false)
+    # Disable if settings are set to Asynchronous loading
+    if Setting.plugin_redmine_tiny_features.key?('load_issue_edit_form_asynchronously').present? && !force_load
+      false
+    else
+      super()
+    end
+  end
+
 end
 
 class IssuesController
 
+  prepend RedmineTinyFeatures::IssuesControllerPatch
+
   append_before_action :find_optional_project_for_new_issue, :only => [:new]
-  skip_before_action :authorize, :only => [:render_form_by_ajax, :switch_display_mode]
+  skip_before_action :authorize, :only => [:render_form_by_ajax, :switch_display_mode, :load_previous_and_next_issue_ids]
 
   def render_form_by_ajax
     @issue = Issue.find(params[:id])
@@ -25,6 +36,12 @@ def switch_display_mode
     redirect_to params[:path]
   end
 
+  def load_previous_and_next_issue_ids
+    find_issue
+    retrieve_previous_and_next_issue_ids(true)
+    render json: { html: render_to_string(partial: 'issues/previous_and_next_issue_ids') }
+  end
+
   private
 
   def find_optional_project_for_new_issue

spec/controllers/issues_controller_spec.rb

@@ -166,4 +166,35 @@
 
   end
 
+  describe '#retrieve_previous_and_next_issue_ids' do
+
+    let(:issue) { Issue.first }
+
+    context 'with asynchronous loading enabled' do
+      before do
+        Setting.send "plugin_redmine_tiny_features=", {
+          "warning_message_on_closed_issues" => "1",
+          "default_open_status" => "2",
+          "default_project" => "1",
+          "load_issue_edit_form_asynchronously" => "1",
+        }
+      end
+
+      it 'allows patched method to receive an argument' do
+        controller.retrieve_previous_and_next_issue_ids(false)
+      end
+
+      it 'allows patched method to receive true as an argument' do
+        controller.retrieve_previous_and_next_issue_ids(true)
+      end
+
+      it 'renders previous and next issue ids as JSON response' do
+        get :load_previous_and_next_issue_ids, params: { id: issue.id }
+        expect(response).to have_http_status(:success)
+        expect(response.content_type).to include('application/json')
+        expect(JSON.parse(response.body)).to have_key('html')
+      end
+    end
+  end
+
 end

spec/requests/issues_spec.rb

@@ -0,0 +1,26 @@
+require 'rails_helper'
+
+RSpec.describe 'Issues AJAX requests', type: :request do
+
+  fixtures :issues
+
+  let(:issue) { Issue.first }
+
+  describe 'GET /issues/render_form_by_ajax/:id' do
+    it 'loads the edit form asynchronously' do
+      get render_form_by_ajax_path(issue.id)
+      expect(response).to have_http_status(:success)
+      expect(response.content_type).to include('application/json')
+      expect(JSON.parse(response.body)).to have_key('html')
+    end
+  end
+
+  describe 'GET /issues/load_previous_and_next_issue_ids/:id' do
+    it 'loads previous and next issue ids asynchronously' do
+      get load_previous_and_next_issue_ids_path(issue.id)
+      expect(response).to have_http_status(:success)
+      expect(response.content_type).to include('application/json')
+      expect(JSON.parse(response.body)).to have_key('html')
+    end
+  end
+end