Add tests for events controller

app/controllers/events_controller.rb

@@ -20,8 +20,8 @@ class EventsController < ApplicationController
   end
 
   def event_params
-    params[:event].permit(:category, :data, :exercise_id, :file_id)
+    params[:event]&.permit(:category, :data, :exercise_id, :file_id)
-        .merge(user_id: current_user&.id, user_type: current_user&.class.name)
+        &.merge(user_id: current_user&.id, user_type: current_user&.class.name)
   end
   private :event_params
 

spec/controllers/events_controller_spec.rb

@@ -0,0 +1,33 @@
+require 'rails_helper'
+
+describe EventsController do
+  let(:user) { FactoryBot.create(:admin) }
+  let(:exercise) {FactoryBot.create(:fibonacci)}
+  before(:each) { allow(controller).to receive(:current_user).and_return(user) }
+
+  describe 'POST #create' do
+    context 'with a valid event' do
+      let(:request) { proc { post :create, event: {category: 'foo', data: 'bar', exercise_id: exercise.id, file_id: exercise.files[0].id} } }
+      before(:each) { request.call }
+
+      expect_assigns(event: Event)
+
+      it 'creates the Event' do
+        expect { request.call }.to change(Event, :count).by(1)
+      end
+
+      expect_status(201)
+    end
+
+    context 'with an invalid event' do
+      before(:each) { post :create, event: {exercise_id: 847482} }
+      expect_assigns(event: Event)
+      expect_status(422)
+    end
+
+    context 'with no event' do
+      before(:each) { post :create }
+      expect_status(422)
+    end
+  end
+end