Minor adjustment to model association validation

app/models/car_detail.rb

@@ -1,6 +1,7 @@
 class CarDetail < ApplicationRecord
   belongs_to :car
   belongs_to :engine_type
+
   validates :horsepower, :torque, numericality: { only_integer: true, greater_than: 0 }
   validates :fuel_economy, :seating_capacity, :cargo_space, :infotainment_system, :safety_rating, :tech_features,
             :special_features, presence: true

app/models/engine_type.rb

@@ -1,4 +1,5 @@
 class EngineType < ApplicationRecord
   has_many :car_details, dependent: :destroy
+
   validates :name, presence: true, length: { maximum: 255 }
 end

app/models/reservation.rb

@@ -3,7 +3,7 @@ class Reservation < ApplicationRecord
   belongs_to :car
   belongs_to :user
 
-  validates :date, :car_id, :city_id, :user_id, presence: true
+  validates :date, presence: true
   validate :date_cannot_be_in_the_past
 
   def date_cannot_be_in_the_past