Don't type cast the default on the column

If we want to have type decorators mess with the attribute, but not the
column, we need to stop type casting on the column. Where possible, we
changed the tests to test the value of `column_defaults`, which is
public API. `Column#default` is not.

17 files changed, 60 insertions, 68 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
index 5a0efe49c7..9bd0401e40 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
@@ -23,7 +23,8 @@ module ActiveRecord
         spec[:precision] = column.precision.inspect if column.precision
         spec[:scale]     = column.scale.inspect if column.scale
         spec[:null]      = 'false' unless column.null
-        spec[:default]   = column.type_cast_for_schema(column.default) if column.has_default?
+        spec[:default]   = schema_default(column) if column.has_default?
+        spec.delete(:default) if spec[:default].nil?
         spec
       end
 
@@ -31,6 +32,15 @@ module ActiveRecord
       def migration_keys
         [:name, :limit, :precision, :scale, :default, :null]
       end
+
+      private
+
+      def schema_default(column)
+        default = column.type_cast_from_database(column.default)
+        unless default.nil?
+          column.type_cast_for_schema(default)
+        end
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
index a9b97d5919..3ef8878ad1 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -62,15 +62,14 @@ module ActiveRecord
           @extra     = extra
           super(name, default, cast_type, sql_type, null)
           assert_valid_default(default)
+          extract_default
         end
 
-        def default
-          @default ||= if blob_or_text_column?
-            null || strict ? nil : ''
-          elsif missing_default_forged_as_empty_string?(@original_default)
-            nil
-          else
-            super
+        def extract_default
+          if blob_or_text_column?
+            @default = null || strict ? nil : ''
+          elsif missing_default_forged_as_empty_string?(@default)
+            @default = nil
           end
         end
 
diff --git a/activerecord/lib/active_record/connection_adapters/column.rb b/activerecord/lib/active_record/connection_adapters/column.rb
index d629fca911..8be4678ace 100644
--- a/activerecord/lib/active_record/connection_adapters/column.rb
+++ b/activerecord/lib/active_record/connection_adapters/column.rb
@@ -13,7 +13,7 @@ module ActiveRecord
         ISO_DATETIME = /\A(\d{4})-(\d\d)-(\d\d) (\d\d):(\d\d):(\d\d)(\.\d+)?\z/
       end
 
-      attr_reader :name, :cast_type, :null, :sql_type, :default_function
+      attr_reader :name, :cast_type, :null, :sql_type, :default, :default_function
 
       delegate :type, :precision, :scale, :limit, :klass, :accessor,
         :text?, :number?, :binary?, :changed?,
@@ -35,7 +35,7 @@ module ActiveRecord
         @cast_type        = cast_type
         @sql_type         = sql_type
         @null             = null
-        @original_default = default
+        @default          = default
         @default_function = nil
       end
 
@@ -51,13 +51,8 @@ module ActiveRecord
         Base.human_attribute_name(@name)
       end
 
-      def default
-        @default ||= type_cast_from_database(@original_default)
-      end
-
       def with_type(type)
         dup.tap do |clone|
-          clone.instance_variable_set('@default', nil)
           clone.instance_variable_set('@cast_type', type)
         end
       end
diff --git a/activerecord/lib/active_record/model_schema.rb b/activerecord/lib/active_record/model_schema.rb
index b9558b0752..fad7eae461 100644
--- a/activerecord/lib/active_record/model_schema.rb
+++ b/activerecord/lib/active_record/model_schema.rb
@@ -230,14 +230,16 @@ module ActiveRecord
       # Returns a hash where the keys are column names and the values are
       # default values when instantiating the AR object for this table.
       def column_defaults
-        @column_defaults ||= Hash[columns.map { |c| [c.name, c.default] }]
+        @column_defaults ||= Hash[columns_hash.map { |name, column|
+          [name, column.type_cast_from_database(column.default)]
+        }]
       end
 
       # Returns a hash where the keys are the column names and the values
       # are the default values suitable for use in `@raw_attriubtes`
       def raw_column_defaults # :nodoc:
-        @raw_column_defauts ||= Hash[column_defaults.map { |name, default|
-          [name, columns_hash[name].type_cast_for_database(default)]
+        @raw_column_defaults ||= Hash[columns_hash.map { |name, column|
+          [name, column.default]
         }]
       end
 
@@ -285,7 +287,7 @@ module ActiveRecord
 
         @arel_engine             = nil
         @column_defaults         = nil
-        @raw_column_defauts      = nil
+        @raw_column_defaults     = nil
         @column_names            = nil
         @column_types            = nil
         @content_columns         = nil
diff --git a/activerecord/test/cases/adapters/postgresql/array_test.rb b/activerecord/test/cases/adapters/postgresql/array_test.rb
index 0b1e3295cc..bdd2f4f4f9 100644
--- a/activerecord/test/cases/adapters/postgresql/array_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/array_test.rb
@@ -41,9 +41,8 @@ class PostgresqlArrayTest < ActiveRecord::TestCase
   def test_default
     @connection.add_column 'pg_arrays', 'score', :integer, array: true, default: [4, 4, 2]
     PgArray.reset_column_information
-    column = PgArray.columns_hash["score"]
 
-    assert_equal([4, 4, 2], column.default)
+    assert_equal([4, 4, 2], PgArray.column_defaults['score'])
     assert_equal([4, 4, 2], PgArray.new.score)
   ensure
     PgArray.reset_column_information
@@ -52,9 +51,8 @@ class PostgresqlArrayTest < ActiveRecord::TestCase
   def test_default_strings
     @connection.add_column 'pg_arrays', 'names', :string, array: true, default: ["foo", "bar"]
     PgArray.reset_column_information
-    column = PgArray.columns_hash["names"]
 
-    assert_equal(["foo", "bar"], column.default)
+    assert_equal(["foo", "bar"], PgArray.column_defaults['names'])
     assert_equal(["foo", "bar"], PgArray.new.names)
   ensure
     PgArray.reset_column_information
@@ -68,7 +66,7 @@ class PostgresqlArrayTest < ActiveRecord::TestCase
     column = PgArray.columns_hash['snippets']
 
     assert_equal :text, column.type
-    assert_equal [], column.default
+    assert_equal [], PgArray.column_defaults['snippets']
     assert column.array
   end
 
@@ -85,8 +83,7 @@ class PostgresqlArrayTest < ActiveRecord::TestCase
     @connection.change_column_default :pg_arrays, :tags, []
 
     PgArray.reset_column_information
-    column = PgArray.columns_hash['tags']
-    assert_equal [], column.default
+    assert_equal [], PgArray.column_defaults['tags']
   end
 
   def test_type_cast_array
diff --git a/activerecord/test/cases/adapters/postgresql/bit_string_test.rb b/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
index 3a9397bc26..9ee3610afd 100644
--- a/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/bit_string_test.rb
@@ -43,12 +43,10 @@ class PostgresqlBitStringTest < ActiveRecord::TestCase
   end
 
   def test_default
-    column = PostgresqlBitString.columns_hash["a_bit"]
-    assert_equal "00000011", column.default
+    assert_equal "00000011", PostgresqlBitString.column_defaults['a_bit']
     assert_equal "00000011", PostgresqlBitString.new.a_bit
 
-    column = PostgresqlBitString.columns_hash["a_bit_varying"]
-    assert_equal "0011", column.default
+    assert_equal "0011", PostgresqlBitString.column_defaults['a_bit_varying']
     assert_equal "0011", PostgresqlBitString.new.a_bit_varying
   end
 
diff --git a/activerecord/test/cases/adapters/postgresql/enum_test.rb b/activerecord/test/cases/adapters/postgresql/enum_test.rb
index b809f1a79c..0e97f37a6c 100644
--- a/activerecord/test/cases/adapters/postgresql/enum_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/enum_test.rb
@@ -42,9 +42,8 @@ class PostgresqlEnumTest < ActiveRecord::TestCase
   def test_enum_defaults
     @connection.add_column 'postgresql_enums', 'good_mood', :mood, default: 'happy'
     PostgresqlEnum.reset_column_information
-    column = PostgresqlEnum.columns_hash["good_mood"]
 
-    assert_equal "happy", column.default
+    assert_equal "happy", PostgresqlEnum.column_defaults['good_mood']
     assert_equal "happy", PostgresqlEnum.new.good_mood
   ensure
     PostgresqlEnum.reset_column_information
diff --git a/activerecord/test/cases/adapters/postgresql/geometric_test.rb b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
index 2f106ee664..8dfc452cf2 100644
--- a/activerecord/test/cases/adapters/postgresql/geometric_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/geometric_test.rb
@@ -35,12 +35,10 @@ class PostgresqlPointTest < ActiveRecord::TestCase
   end
 
   def test_default
-    column = PostgresqlPoint.columns_hash["y"]
-    assert_equal [12.2, 13.3], column.default
+    assert_equal [12.2, 13.3], PostgresqlPoint.column_defaults['y']
     assert_equal [12.2, 13.3], PostgresqlPoint.new.y
 
-    column = PostgresqlPoint.columns_hash["z"]
-    assert_equal [14.4, 15.5], column.default
+    assert_equal [14.4, 15.5], PostgresqlPoint.column_defaults['z']
     assert_equal [14.4, 15.5], PostgresqlPoint.new.z
   end
 
diff --git a/activerecord/test/cases/adapters/postgresql/hstore_test.rb b/activerecord/test/cases/adapters/postgresql/hstore_test.rb
index c4e2917251..06788df4e1 100644
--- a/activerecord/test/cases/adapters/postgresql/hstore_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/hstore_test.rb
@@ -64,9 +64,8 @@ class PostgresqlHstoreTest < ActiveRecord::TestCase
     def test_default
       @connection.add_column 'hstores', 'permissions', :hstore, default: '"users"=>"read", "articles"=>"write"'
       Hstore.reset_column_information
-      column = Hstore.columns_hash["permissions"]
 
-      assert_equal({"users"=>"read", "articles"=>"write"}, column.default)
+      assert_equal({"users"=>"read", "articles"=>"write"}, Hstore.column_defaults['permissions'])
       assert_equal({"users"=>"read", "articles"=>"write"}, Hstore.new.permissions)
     ensure
       Hstore.reset_column_information
diff --git a/activerecord/test/cases/adapters/postgresql/json_test.rb b/activerecord/test/cases/adapters/postgresql/json_test.rb
index 3c07209472..4cdb4a4893 100644
--- a/activerecord/test/cases/adapters/postgresql/json_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/json_test.rb
@@ -43,9 +43,8 @@ class PostgresqlJSONTest < ActiveRecord::TestCase
   def test_default
     @connection.add_column 'json_data_type', 'permissions', :json, default: '{"users": "read", "posts": ["read", "write"]}'
     JsonDataType.reset_column_information
-    column = JsonDataType.columns_hash["permissions"]
 
-    assert_equal({"users"=>"read", "posts"=>["read", "write"]}, column.default)
+    assert_equal({"users"=>"read", "posts"=>["read", "write"]}, JsonDataType.column_defaults['permissions'])
     assert_equal({"users"=>"read", "posts"=>["read", "write"]}, JsonDataType.new.permissions)
   ensure
     JsonDataType.reset_column_information
diff --git a/activerecord/test/cases/adapters/postgresql/money_test.rb b/activerecord/test/cases/adapters/postgresql/money_test.rb
index bdfeedafab..cf2a4ab6ea 100644
--- a/activerecord/test/cases/adapters/postgresql/money_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/money_test.rb
@@ -32,8 +32,7 @@ class PostgresqlMoneyTest < ActiveRecord::TestCase
   end
 
   def test_default
-    column = PostgresqlMoney.columns_hash["depth"]
-    assert_equal BigDecimal.new("150.55"), column.default
+    assert_equal BigDecimal.new("150.55"), PostgresqlMoney.column_defaults['depth']
     assert_equal BigDecimal.new("150.55"), PostgresqlMoney.new.depth
   end
 
diff --git a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
index e55525177f..b89caa3d55 100644
--- a/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/sqlite3_adapter_test.rb
@@ -339,7 +339,7 @@ module ActiveRecord
           column = @conn.columns('ex').find { |x|
             x.name == 'number'
           }
-          assert_equal 10, column.default
+          assert_equal '10', column.default
         end
       end
 
diff --git a/activerecord/test/cases/attribute_decorators_test.rb b/activerecord/test/cases/attribute_decorators_test.rb
index bc3e9a8cf5..b352d1a6c2 100644
--- a/activerecord/test/cases/attribute_decorators_test.rb
+++ b/activerecord/test/cases/attribute_decorators_test.rb
@@ -98,17 +98,7 @@ module ActiveRecord
       assert_equal 'Hello! decorated!', model.a_string
       assert_equal 'whatever', model.another_string
       assert_equal 'Hello! decorated! decorated!', child.a_string
-      # We are round tripping the default, and we don't undo our decoration
-      assert_equal 'whatever decorated! decorated!', child.another_string
-    end
-
-    test "defaults are decorated on the column" do
-      Model.attribute :a_string, Type::String.new, default: 'whatever'
-      Model.decorate_attribute_type(:a_string, :test) { |t| StringDecorator.new(t) }
-
-      column = Model.columns_hash['a_string']
-
-      assert_equal 'whatever decorated!', column.default
+      assert_equal 'whatever decorated!', child.another_string
     end
 
     class Multiplier < SimpleDelegator
diff --git a/activerecord/test/cases/defaults_test.rb b/activerecord/test/cases/defaults_test.rb
index 92144bc802..c089e63128 100644
--- a/activerecord/test/cases/defaults_test.rb
+++ b/activerecord/test/cases/defaults_test.rb
@@ -154,7 +154,7 @@ if current_adapter?(:MysqlAdapter, :Mysql2Adapter)
         t.column :omit, :integer, :null => false
       end
 
-      assert_equal 0, klass.columns_hash['zero'].default
+      assert_equal '0', klass.columns_hash['zero'].default
       assert !klass.columns_hash['zero'].null
       # 0 in MySQL 4, nil in 5.
       assert [0, nil].include?(klass.columns_hash['omit'].default)
diff --git a/activerecord/test/cases/migration/change_schema_test.rb b/activerecord/test/cases/migration/change_schema_test.rb
index 9b26c30d14..c66eaf1ee1 100644
--- a/activerecord/test/cases/migration/change_schema_test.rb
+++ b/activerecord/test/cases/migration/change_schema_test.rb
@@ -68,9 +68,9 @@ module ActiveRecord
         five = columns.detect { |c| c.name == "five" } unless mysql
 
         assert_equal "hello", one.default
-        assert_equal true, two.default
-        assert_equal false, three.default
-        assert_equal 1, four.default
+        assert_equal true, two.type_cast_from_database(two.default)
+        assert_equal false, three.type_cast_from_database(three.default)
+        assert_equal '1', four.default
         assert_equal "hello", five.default unless mysql
       end
 
@@ -275,7 +275,7 @@ module ActiveRecord
 
         person_klass.connection.add_column "testings", "wealth", :integer, :null => false, :default => 99
         person_klass.reset_column_information
-        assert_equal 99, person_klass.columns_hash["wealth"].default
+        assert_equal 99, person_klass.column_defaults["wealth"]
         assert_equal false, person_klass.columns_hash["wealth"].null
         # Oracle needs primary key value from sequence
         if current_adapter?(:OracleAdapter)
@@ -287,20 +287,20 @@ module ActiveRecord
         # change column default to see that column doesn't lose its not null definition
         person_klass.connection.change_column_default "testings", "wealth", 100
         person_klass.reset_column_information
-        assert_equal 100, person_klass.columns_hash["wealth"].default
+        assert_equal 100, person_klass.column_defaults["wealth"]
         assert_equal false, person_klass.columns_hash["wealth"].null
 
         # rename column to see that column doesn't lose its not null and/or default definition
         person_klass.connection.rename_column "testings", "wealth", "money"
         person_klass.reset_column_information
         assert_nil person_klass.columns_hash["wealth"]
-        assert_equal 100, person_klass.columns_hash["money"].default
+        assert_equal 100, person_klass.column_defaults["money"]
         assert_equal false, person_klass.columns_hash["money"].null
 
         # change column
         person_klass.connection.change_column "testings", "money", :integer, :null => false, :default => 1000
         person_klass.reset_column_information
-        assert_equal 1000, person_klass.columns_hash["money"].default
+        assert_equal 1000, person_klass.column_defaults["money"]
         assert_equal false, person_klass.columns_hash["money"].null
 
         # change column, make it nullable and clear default
diff --git a/activerecord/test/cases/migration/columns_test.rb b/activerecord/test/cases/migration/columns_test.rb
index a7c287515d..4e6d7963aa 100644
--- a/activerecord/test/cases/migration/columns_test.rb
+++ b/activerecord/test/cases/migration/columns_test.rb
@@ -53,13 +53,13 @@ module ActiveRecord
         add_column 'test_models', 'salary', :integer, :default => 70000
 
         default_before = connection.columns("test_models").find { |c| c.name == "salary" }.default
-        assert_equal 70000, default_before
+        assert_equal '70000', default_before
 
         rename_column "test_models", "salary", "annual_salary"
 
         assert TestModel.column_names.include?("annual_salary")
         default_after = connection.columns("test_models").find { |c| c.name == "annual_salary" }.default
-        assert_equal 70000, default_after
+        assert_equal '70000', default_after
       end
 
       if current_adapter?(:MysqlAdapter, :Mysql2Adapter)
@@ -193,14 +193,21 @@ module ActiveRecord
 
         old_columns = connection.columns(TestModel.table_name)
         assert old_columns.find { |c|
-          c.name == 'approved' && c.type == :boolean && c.default == true
+          default = c.type_cast_from_database(c.default)
+          c.name == 'approved' && c.type == :boolean && default == true
         }
 
         change_column :test_models, :approved, :boolean, :default => false
         new_columns = connection.columns(TestModel.table_name)
 
-        assert_not new_columns.find { |c| c.name == 'approved' and c.type == :boolean and c.default == true }
-        assert new_columns.find { |c| c.name == 'approved' and c.type == :boolean and c.default == false }
+        assert_not new_columns.find { |c|
+          default = c.type_cast_from_database(c.default)
+          c.name == 'approved' and c.type == :boolean and default == true
+        }
+        assert new_columns.find { |c|
+          default = c.type_cast_from_database(c.default)
+          c.name == 'approved' and c.type == :boolean and default == false
+        }
         change_column :test_models, :approved, :boolean, :default => true
       end
 
diff --git a/activerecord/test/cases/migration_test.rb b/activerecord/test/cases/migration_test.rb
index 9855835e27..6b840e16bb 100644
--- a/activerecord/test/cases/migration_test.rb
+++ b/activerecord/test/cases/migration_test.rb
@@ -567,7 +567,7 @@ if ActiveRecord::Base.connection.supports_bulk_alter?
 
       assert_equal 8, columns.size
       [:name, :qualification, :experience].each {|s| assert_equal :string, column(s).type }
-      assert_equal 0, column(:age).default
+      assert_equal '0', column(:age).default
     end
 
     def test_removing_columns