[#4604] Clear and recalculate the #cost on Rate#destroy

app/models/rate.rb

@@ -13,6 +13,7 @@ class Rate < ActiveRecord::Base
   before_save :unlocked?
   after_save :update_time_entry_cost_cache
   before_destroy :unlocked?
+  after_destroy :update_time_entry_cost_cache
   
   named_scope :history_for_user, lambda { |user, order|
     {

test/unit/rate_test.rb

@@ -106,6 +106,32 @@ class RateTest < ActiveSupport::TestCase
     
   end
   
+  context "after destroy" do
+    should "recalculate all of the cached cost of all Time Entries for the user" do
+      @user = User.generate!
+      @project = Project.generate!
+      @date = Date.today.to_s
+      @past_date = 1.month.ago.strftime('%Y-%m-%d')
+      @rate = Rate.generate!(:user => @user, :project => @project, :date_in_effect => @date, :amount => 200.0)
+      @old_rate = Rate.generate!(:user => @user, :project => @project, :date_in_effect => 2.months.ago.strftime('%Y-%m-%d'), :amount => 10.0)
+
+      @time_entry1 = TimeEntry.generate!({:user => @user, :project => @project, :spent_on => @date, :hours => 10.0, :activity => TimeEntryActivity.generate!})
+      @time_entry2 = TimeEntry.generate!({:user => @user, :project => @project, :spent_on => @past_date, :hours => 20.0, :activity => TimeEntryActivity.generate!})
+
+
+      assert_equal 2000.00, @time_entry1.cost
+      assert_equal 2000.00, @time_entry1.read_attribute(:cost)
+      assert_equal 200.0, @time_entry2.cost
+      assert_equal 200.0, @time_entry2.read_attribute(:cost)
+
+      @old_rate.destroy
+
+      assert_equal 2000.0, TimeEntry.find(@time_entry1.id).cost
+      assert_equal 0, TimeEntry.find(@time_entry2.id).cost
+    end
+    
+  end
+
   context '#for' do
     setup do
       @user = User.generate!