Add endpoint to allow users to remove lists

app/controllers/projects/board_lists_controller.rb

@@ -25,6 +25,18 @@ class Projects::BoardListsController < Projects::ApplicationController
     end
   end
 
+  def destroy
+    service = Boards::Lists::DestroyService.new(project, params)
+
+    respond_to do |format|
+      if service.execute
+        format.json { head :ok }
+      else
+        format.json { head :unprocessable_entity }
+      end
+    end
+  end
+
   private
 
   def record_not_found(exception)

config/routes.rb

@@ -857,7 +857,7 @@ Rails.application.routes.draw do
         end
 
         resource :board, only: [:show] do
-          resources :lists, only: [:create, :update], controller: :board_lists
+          resources :lists, only: [:create, :update, :destroy], controller: :board_lists
         end
 
         resources :todos, only: [:create]

spec/controllers/projects/board_lists_controller_spec.rb

@@ -97,5 +97,39 @@ describe Projects::BoardListsController do
       end
     end
   end
+
+  describe 'DELETE #destroy' do
+    context 'with valid list id' do
+      let!(:planning) { create(:list, board: project.board, position: 1) }
+
+      it 'returns a successful 200 response' do
+        delete :destroy, namespace_id: project.namespace.to_param,
+                         project_id: project.to_param,
+                         id: planning.to_param,
+                         format: :json
+
+        expect(response).to have_http_status(200)
+      end
+
+      it 'removes list from board' do
+        expect do
+          delete :destroy, namespace_id: project.namespace.to_param,
+                           project_id: project.to_param,
+                           id: planning.to_param,
+                           format: :json
+        end.to change(project.board.lists, :size).by(-1)
+      end
+    end
+
+    context 'with invalid list id' do
+      it 'returns a not found 404 response' do
+        delete :destroy, namespace_id: project.namespace.to_param,
+                         project_id: project.to_param,
+                         id: 999,
+                         format: :json
+
+        expect(response).to have_http_status(404)
+      end
+    end
   end
 end