adds User#age

app/models/user.rb

@@ -246,6 +246,14 @@ class User < ActiveRecord::Base
     "#{name} (#{email})"
   end
 
+  def age
+    if date_of_birth.blank?
+      nil
+    else
+      ((Date.today - date_of_birth.to_date).to_i / 365.25).to_i
+    end
+  end
+
   def save_requiring_finish_signup
     begin
       self.registering_with_oauth = true

spec/models/user_spec.rb

@@ -65,6 +65,13 @@ describe User do
     end
   end
 
+  describe "#age" do
+    it "is the rounded integer age based on the date_of_birth" do
+      user = create(:user, date_of_birth: 33.years.ago)
+      expect(user.age).to eq(33)
+    end
+  end
+
   describe 'preferences' do
     describe 'email_on_comment' do
       it 'should be false by default' do