[thoughtbot#74] initialize salt for old user records without salt

lib/clearance/user.rb

@@ -143,7 +143,7 @@ def generate_hash(string)
       end
 
       def initialize_salt
-        if new_record?
+        if salt.blank?
           self.salt = generate_hash("--#{Time.now.utc}--#{password}--#{rand}--")
         end
       end

test/models/user_test.rb

@@ -28,6 +28,16 @@ class UserTest < ActiveSupport::TestCase
       assert_not_nil Factory(:user).salt
     end
 
+    should "initialize salt for old user records without salt" do
+      user = Factory(:user)
+      sql  = "update users set salt = NULL where id = #{user.id}"
+      ActiveRecord::Base.connection.update(sql)
+      assert_nil user.reload.salt
+
+      user.save
+      assert_not_nil user.salt
+    end
+
     should "initialize confirmation token" do
       assert_not_nil Factory(:user).confirmation_token
     end