check if attrs exist before comparing and stop pre-populating the ins…

…tant variable Sf::Contact#diffs

lib/sf/contact.rb

@@ -46,16 +46,7 @@ def set_person_by_email(email)
   end
 
   def get_diffs
-    unless self.Id.nil?
-      sf_person_mapping.each do |p, sf|
-        diffs[p.to_sym] = true unless self.send(sf).eql? person.send(p)
-      end
-    else
-      sf_person_mapping.each do |p, sf|
-        diffs[p.to_sym] = true
-      end
-    end
-    diffs
+    self.Id.nil? ? flag_all_attrbutes_as_diff : flag_attributes_if_different
   end
 
   def attrs_from_person
@@ -199,4 +190,17 @@ def self.build_contacts(from, where)
       IN (SELECT Contact__c FROM #{from} where #{where})"
     )
   end
+
+  def flag_all_attrbutes_as_diff
+    sf_person_mapping.merge(sf_person_mapping) do |p, sf|
+      true if person.respond_to?(p)
+    end.compact
+  end
+
+  def flag_attributes_if_different
+    sf_person_mapping.merge(sf_person_mapping) do |p, sf|
+      true if person.respond_to?(p) and !self.send(sf).eql?(person.send(p))
+    end.compact
+  end
+
 end