2 files changed, 10 insertions, 8 deletions
diff --git a/activemodel/lib/active_model/dirty.rb b/activemodel/lib/active_model/dirty.rb
index 6e2e5afd1b..90047c3c12 100644
--- a/activemodel/lib/active_model/dirty.rb
+++ b/activemodel/lib/active_model/dirty.rb
@@ -119,6 +119,9 @@ module ActiveModel
     extend ActiveSupport::Concern
     include ActiveModel::AttributeMethods
 
+    OPTION_NOT_GIVEN = Object.new # :nodoc:
+    private_constant :OPTION_NOT_GIVEN
+
     included do
       attribute_method_suffix '_changed?', '_change', '_will_change!', '_was'
       attribute_method_suffix '_previously_changed?', '_previous_change'
@@ -174,11 +177,10 @@ module ActiveModel
     end
 
     # Handles <tt>*_changed?</tt> for +method_missing+.
-    def attribute_changed?(attr, options = {}) #:nodoc:
-      result = changes_include?(attr)
-      result &&= options[:to] == __send__(attr) if options.key?(:to)
-      result &&= options[:from] == changed_attributes[attr] if options.key?(:from)
-      result
+    def attribute_changed?(attr, from: OPTION_NOT_GIVEN, to: OPTION_NOT_GIVEN) # :nodoc:
+      !!changes_include?(attr) &&
+        (to == OPTION_NOT_GIVEN || to == __send__(attr)) &&
+        (from == OPTION_NOT_GIVEN || from == changed_attributes[attr])
     end
 
     # Handles <tt>*_was</tt> for +method_missing+.
@@ -187,7 +189,7 @@ module ActiveModel
     end
 
     # Handles <tt>*_previously_changed?</tt> for +method_missing+.
-    def attribute_previously_changed?(attr, options = {}) #:nodoc:
+    def attribute_previously_changed?(attr) #:nodoc:
       previous_changes_include?(attr)
     end
 
diff --git a/activemodel/lib/active_model/errors.rb b/activemodel/lib/active_model/errors.rb
index d925960b41..d106f65fa2 100644
--- a/activemodel/lib/active_model/errors.rb
+++ b/activemodel/lib/active_model/errors.rb
@@ -346,7 +346,7 @@ module ActiveModel
     #   # => {:name=>["can't be empty"]}
     def add_on_empty(attributes, options = {})
       ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-        ActiveModel::Errors#add_on_empty is deprecated and will be removed in Rails 5.1
+        ActiveModel::Errors#add_on_empty is deprecated and will be removed in Rails 5.1.
 
         To achieve the same use:
 
@@ -368,7 +368,7 @@ module ActiveModel
     #   # => {:name=>["can't be blank"]}
     def add_on_blank(attributes, options = {})
       ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
-        ActiveModel::Errors#add_on_blank is deprecated and will be removed in Rails 5.1
+        ActiveModel::Errors#add_on_blank is deprecated and will be removed in Rails 5.1.
 
         To achieve the same use: