initial Rails 3 rewrite commit

completely rewritten for ActiveModel compatibility
uses ActiveModel EachValidator class as validator base class
simplifies :between by splitting into a :on_or_before and an :on_of_after
only :is_at option tested

spec/model_helpers.rb

@@ -0,0 +1,27 @@
+module ModelHelpers 
+
+  # Some test helpers from Rails source 
+  def invalid!(attr_name, values, error = nil)
+    with_each_person_value(attr_name, values) do |record, value|
+      record.should be_invalid
+      record.errors[attr_name].size.should >= 1
+      record.errors[attr_name].first.should == error if error
+    end
+  end
+
+  def valid!(attr_name, values)
+    with_each_person_value(attr_name, values) do |record, value|
+      record.should be_valid
+    end
+  end
+
+  def with_each_person_value(attr_name, values)
+    record = Person.new
+    values = [values] unless values.is_a?(Array)
+    values.each do |value|
+      record.send("#{attr_name}=", value)
+      yield record, value
+    end
+  end
+
+end