Add comprehensive unit test coverage for controllers, models, and services

- Translate French comments to English in controllers and tests
- Fix test failures: route helpers, validations, MySQL transaction issues
- Add Timecop for time-dependent tests and update database config for isolation

test/controllers/api/v1/events_controller_test.rb

@@ -0,0 +1,58 @@
+require "test_helper"
+
+class Api::V1::EventsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    ENV["API_KEY"] = "test_key"
+    @user = User.create!(email: "test@example.com", password: "password123", password_confirmation: "password123")
+    @event = Event.create!(name: "Test Event", slug: "test-event", description: "A description that is long enough for validation", latitude: 48.8566, longitude: 2.3522, venue_name: "Venue", venue_address: "Address", user: @user, start_time: 1.week.from_now, end_time: 1.week.from_now + 3.hours, state: :published)
+  end
+
+  test "should get index" do
+    get api_v1_events_url, headers: headers_api_key
+    assert_response :success
+    assert_kind_of Array, json_response
+  end
+
+  test "should show event" do
+    get api_v1_event_url(@event.id), headers: headers_api_key
+    assert_response :success
+    assert_equal @event.id, json_response["id"]
+  end
+
+  test "should create event" do
+    assert_difference("Event.count") do
+      post api_v1_events_url, params: { event: { name: "New Event", slug: "new-event", description: "New description that is long enough", latitude: 48.8566, longitude: 2.3522, venue_name: "New Venue", venue_address: "New Address", user_id: @user.id, start_time: "2024-01-01 10:00:00", end_time: "2024-01-01 13:00:00", state: "published" } }, as: :json, headers: headers_api_key
+    end
+    assert_response :created
+  end
+
+  test "should update event" do
+    patch api_v1_event_url(@event.id), params: { event: { name: "Updated Event" } }, as: :json, headers: headers_api_key
+    assert_response :ok
+    @event.reload
+    assert_equal "Updated Event", @event.name
+  end
+
+  test "should destroy event" do
+    assert_difference("Event.count", -1) do
+      delete api_v1_event_url(@event.id), headers: headers_api_key
+    end
+    assert_response :no_content
+  end
+
+  test "should store cart" do
+    post store_cart_api_v1_event_url(@event), params: { cart: { ticket_type_id: 1, quantity: 2 } }, as: :json
+    assert_response :success
+    assert_equal @event.id, session[:event_id]
+  end
+
+  private
+
+  def json_response
+    JSON.parse(response.body)
+  end
+
+  def headers_api_key
+    { "X-API-Key" => "test_key" }
+  end
+end