4 files changed, 19 insertions, 4 deletions
diff --git a/activerecord/lib/active_record/enum.rb b/activerecord/lib/active_record/enum.rb
index 8655f68308..b942fa6273 100644
--- a/activerecord/lib/active_record/enum.rb
+++ b/activerecord/lib/active_record/enum.rb
@@ -105,9 +105,10 @@ module ActiveRecord
     end
 
     class EnumType < Type::Value # :nodoc:
-      def initialize(name, mapping)
+      def initialize(name, mapping, subtype)
         @name = name
         @mapping = mapping
+        @subtype = subtype
       end
 
       def cast(value)
@@ -124,7 +125,7 @@ module ActiveRecord
 
       def deserialize(value)
         return if value.nil?
-        mapping.key(value)
+        mapping.key(subtype.deserialize(value))
       end
 
       def serialize(value)
@@ -139,7 +140,7 @@ module ActiveRecord
 
       protected
 
-      attr_reader :name, :mapping
+      attr_reader :name, :mapping, :subtype
     end
 
     def enum(definitions)
@@ -158,7 +159,9 @@ module ActiveRecord
         detect_enum_conflict!(name, name)
         detect_enum_conflict!(name, "#{name}=")
 
-        attribute name, EnumType.new(name, enum_values)
+        decorate_attribute_type(name, :enum) do |subtype|
+          EnumType.new(name, enum_values, subtype)
+        end
 
         _enum_methods_module.module_eval do
           pairs = values.respond_to?(:each_pair) ? values.each_pair : values.each_with_index
diff --git a/activerecord/test/cases/enum_test.rb b/activerecord/test/cases/enum_test.rb
index 7c930de97b..babacd1ee9 100644
--- a/activerecord/test/cases/enum_test.rb
+++ b/activerecord/test/cases/enum_test.rb
@@ -411,4 +411,14 @@ class EnumTest < ActiveRecord::TestCase
     assert book.proposed?, "expected fixture to default to proposed status"
     assert book.in_english?, "expected fixture to default to english language"
   end
+
+  test "uses default value from database on initialization" do
+    book = Book.new
+    assert book.proposed?
+  end
+
+  test "uses default value from database on initialization when using custom mapping" do
+    book = Book.new
+    assert book.hard?
+  end
 end
diff --git a/activerecord/test/models/book.rb b/activerecord/test/models/book.rb
index 1927191393..e43e5c3901 100644
--- a/activerecord/test/models/book.rb
+++ b/activerecord/test/models/book.rb
@@ -14,6 +14,7 @@ class Book < ActiveRecord::Base
   enum author_visibility: [:visible, :invisible], _prefix: true
   enum illustrator_visibility: [:visible, :invisible], _prefix: true
   enum font_size: [:small, :medium, :large], _prefix: :with, _suffix: true
+  enum cover: { hard: 'hard', soft: 'soft' }
 
   def published!
     super
diff --git a/activerecord/test/schema/schema.rb b/activerecord/test/schema/schema.rb
index 025184f63a..2e1e584156 100644
--- a/activerecord/test/schema/schema.rb
+++ b/activerecord/test/schema/schema.rb
@@ -104,6 +104,7 @@ ActiveRecord::Schema.define do
     t.column :author_visibility, :integer, default: 0
     t.column :illustrator_visibility, :integer, default: 0
     t.column :font_size, :integer, default: 0
+    t.column :cover, :string, default: 'hard'
   end
 
   create_table :booleans, force: true do |t|