issue_categories_sortable.diff - Redmine

       def index
         respond_to do |format|
           format.html {redirect_to_settings_in_projects}
           format.api {@categories = @project.issue_categories.to_a}
           format.api {@categories = @project.issue_categories.sorted.to_a}
         end
       end
-...
               flash[:notice] = l(:notice_successful_update)
               redirect_to_settings_in_projects
             end
             format.js {head 200}
             format.api {render_api_ok}
           end
         else
           respond_to do |format|
             format.html {render :action => 'edit'}
             format.api {render_validation_errors(@category)}
             format.js {head 422}
           end
         end
       end

       belongs_to :project
       belongs_to :assigned_to, :class_name => 'Principal'
       has_many :issues, :foreign_key => 'category_id', :dependent => :nullify
       acts_as_positioned
       validates_presence_of :name
       validates_uniqueness_of :name, :scope => [:project_id]
       validates_length_of :name, :maximum => 60
       safe_attributes 'name', 'assigned_to_id'
       safe_attributes 'name', 'assigned_to_id', 'position'
       scope :sorted, lambda {order(:position)}
       scope :named, lambda {|arg| where("LOWER(#{table_name}.name) = LOWER(?)", arg.to_s.strip)}
       alias :destroy_without_reassign :destroy
-...
       end
       def <=>(category)
         name <=> category.name
         position <=> category.position
       end
       def to_s; name end

       has_many :queries, :dependent => :delete_all
       has_many :documents, :dependent => :destroy
       has_many :news, lambda {includes(:author)}, :dependent => :destroy
       has_many :issue_categories, lambda {order(:name)}, :dependent => :delete_all
       has_many :issue_categories, lambda {order(:position)}, :dependent => :delete_all
       has_many :boards, lambda {order(:position)}, :inverse_of => :project, :dependent => :destroy
       has_one :repository, lambda {where(:is_default => true)}
       has_many :repositories, :dependent => :destroy

     <p><%= link_to l(:label_issue_category_new), new_project_issue_category_path(@project), :class => 'icon icon-add' if User.current.allowed_to?(:manage_categories, @project) %></p>
     <% if @project.issue_categories.any? %>
     <table class="list">
     <table class="list issue_categories">
       <thead><tr>
         <th><%= l(:label_issue_category) %></th>
         <th><%= l(:field_assigned_to) %></th>
-...
         <td><%= category.assigned_to.name if category.assigned_to %></td>
         <td class="buttons">
           <% if User.current.allowed_to?(:manage_categories, @project) %>
             <%= reorder_handle category %>
             <%= link_to l(:button_edit), edit_issue_category_path(category), :class => 'icon icon-edit' %>
             <%= delete_link issue_category_path(category) %>
           <% end %>
-...
     <% else %>
     <p class="nodata"><%= l(:label_no_data) %></p>
     <% end %>
     <%= javascript_tag do %>
       $(function() { $("table.issue_categories tbody").positionedItems(); });
     <% end %>

         end
         member do
           get 'settings(/:tab)', :action => 'settings', :as => 'settings'
           match 'settings(/:tab)', action: 'settings', as: 'settings', via: [:get, :put]
           post 'archive'
           post 'unarchive'
           post 'close'

     class AddIssueCategoryPosition < ActiveRecord::Migration[5.2]
       def self.up
         add_column :issue_categories, :position, :integer, default: 1
         IssueCategory.order(:name).each_with_index { |category, i| category.update_attribute(:position, i + 1) }
       end
       def self.down
         remove_column :issue_categories, :position
       end
     end

       name: Printing
       project_id: 1
       assigned_to_id: 2
       position: 1
       id: 1
     issue_categories_002:
       name: Recipes
       project_id: 1
       assigned_to_id:
       assigned_to_id:
       position: 2
       id: 2
     issue_categories_003:
       name: Stock management
       project_id: 2
       assigned_to_id:
       assigned_to_id:
       position: 3
       id: 3
     issue_categories_004:
       name: Printing
       project_id: 2
       assigned_to_id:
       assigned_to_id:
       position: 4
       id: 4

             :params => {
               :id => 2,
               :issue_category => {
                 :name => 'Testing'
                 :name => 'Testing',
                 :position => 3
+              }
+            }
+          )
         end
         assert_redirected_to '/projects/ecookbook/settings/categories'
         assert_equal 'Testing', IssueCategory.find(2).name
         issue_category = IssueCategory.find(2)
         assert_equal 'Testing', issue_category.name
         assert_equal 3, issue_category.position
       end
       def test_update_failure

test/unit/issue_category_test.rb (working copy)
31	31	assert IssueCategory.new(:project_id => 2, :name => 'New category').save
32	32	category = IssueCategory.order('id DESC').first
33	33	assert_equal 'New category', category.name
	34	assert_equal 1, category.position
34	35	end
35	36
36	37	def test_create_with_group_assignment

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