1 files changed, 14 insertions, 4 deletions
diff --git a/activemodel/lib/active_model/errors.rb b/activemodel/lib/active_model/errors.rb
index 14adfa081f..9df4ca51fe 100644
--- a/activemodel/lib/active_model/errors.rb
+++ b/activemodel/lib/active_model/errors.rb
@@ -110,6 +110,7 @@ module ActiveModel
     #   person.errors.include?(:name) # => true
     #   person.errors.include?(:age)  # => false
     def include?(attribute)
+      attribute = attribute.to_sym
       messages.key?(attribute) && messages[attribute].present?
     end
     alias :has_key? :include?
@@ -121,8 +122,9 @@ module ActiveModel
     #   person.errors.delete(:name) # => ["cannot be nil"]
     #   person.errors[:name]        # => []
     def delete(key)
-      details.delete(key)
-      messages.delete(key)
+      attribute = key.to_sym
+      details.delete(attribute)
+      messages.delete(attribute)
     end
 
     # When passed a symbol or a name of a method, returns an array of errors
@@ -342,6 +344,7 @@ module ActiveModel
     #   person.errors.full_messages_for(:name)
     #   # => ["Name is too short (minimum is 5 characters)", "Name can't be blank"]
     def full_messages_for(attribute)
+      attribute = attribute.to_sym
       messages[attribute].map { |message| full_message(attribute, message) }
     end
 
@@ -416,16 +419,23 @@ module ActiveModel
       I18n.translate(key, options)
     end
 
-    def marshal_dump
+    def marshal_dump # :nodoc:
       [@base, without_default_proc(@messages), without_default_proc(@details)]
     end
 
-    def marshal_load(array)
+    def marshal_load(array) # :nodoc:
       @base, @messages, @details = array
       apply_default_array(@messages)
       apply_default_array(@details)
     end
 
+    def init_with(coder) # :nodoc:
+      coder.map.each { |k, v| instance_variable_set(:"@#{k}", v) }
+      @details ||= {}
+      apply_default_array(@messages)
+      apply_default_array(@details)
+    end
+
   private
     def normalize_message(attribute, message, options)
       case message