give each PG type a `type` method and decortate tz attributes

5 files changed, 60 insertions, 18 deletions

diff --git a/activerecord/lib/active_record/attribute_methods/serialization.rb b/activerecord/lib/active_record/attribute_methods/serialization.rb
index 3bc749dabf..1fe5d9de20 100644
--- a/activerecord/lib/active_record/attribute_methods/serialization.rb
+++ b/activerecord/lib/active_record/attribute_methods/serialization.rb
@@ -18,6 +18,10 @@ module ActiveRecord
         def type_cast(value)
           value.unserialized_value
         end
+
+        def type
+          @column.type
+        end
       end
 
       class Attribute < Struct.new(:coder, :value, :state)
diff --git a/activerecord/lib/active_record/attribute_methods/time_zone_conversion.rb b/activerecord/lib/active_record/attribute_methods/time_zone_conversion.rb
index 19dcceea88..802add9986 100644
--- a/activerecord/lib/active_record/attribute_methods/time_zone_conversion.rb
+++ b/activerecord/lib/active_record/attribute_methods/time_zone_conversion.rb
@@ -4,6 +4,21 @@ require 'active_support/core_ext/object/inclusion'
 module ActiveRecord
   module AttributeMethods
     module TimeZoneConversion
+      class Type # :nodoc:
+        def initialize(column)
+          @column = column
+        end
+
+        def type_cast(value)
+          value = @column.type_cast(value)
+          value.acts_like?(:time) ? value.in_time_zone : value
+        end
+
+        def type
+          @column.type
+        end
+      end
+
       extend ActiveSupport::Concern
 
       included do
@@ -64,7 +79,9 @@ module ActiveRecord
         end
 
         def create_time_zone_conversion_attribute?(name, column)
-          time_zone_aware_attributes && !self.skip_time_zone_conversion_for_attributes.include?(name.to_sym) && column.type.in?([:datetime, :timestamp])
+          time_zone_aware_attributes &&
+            !self.skip_time_zone_conversion_for_attributes.include?(name.to_sym) &&
+            [:datetime, :timestamp].include?(column.type)
         end
       end
     end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
index 3216b7709c..a94259a875 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
@@ -11,19 +11,23 @@ module ActiveRecord
           end
         end
 
-        class Identity
+        class Type
+          def type; end
+        end
+
+        class Identity < Type
           def type_cast(value)
             value
           end
         end
 
-        class Bytea
+        class Bytea < Type
           def type_cast(value)
             PGconn.unescape_bytea value if value
           end
         end
 
-        class Money
+        class Money < Type
           def type_cast(value)
             return if value.nil?
 
@@ -43,7 +47,7 @@ module ActiveRecord
           end
         end
 
-        class Vector
+        class Vector < Type
           attr_reader :delim, :subtype
 
           # +delim+ corresponds to the `typdelim` column in the pg_types
@@ -62,7 +66,7 @@ module ActiveRecord
           end
         end
 
-        class Integer
+        class Integer < Type
           def type_cast(value)
             return if value.nil?
 
@@ -70,7 +74,7 @@ module ActiveRecord
           end
         end
 
-        class Boolean
+        class Boolean < Type
           def type_cast(value)
             return if value.nil?
 
@@ -78,7 +82,9 @@ module ActiveRecord
           end
         end
 
-        class Timestamp
+        class Timestamp < Type
+          def type; :timestamp; end
+
           def type_cast(value)
             return if value.nil?
 
@@ -88,7 +94,9 @@ module ActiveRecord
           end
         end
 
-        class Date
+        class Date < Type
+          def type; :datetime; end
+
           def type_cast(value)
             return if value.nil?
 
@@ -98,7 +106,7 @@ module ActiveRecord
           end
         end
 
-        class Time
+        class Time < Type
           def type_cast(value)
             return if value.nil?
 
@@ -108,7 +116,7 @@ module ActiveRecord
           end
         end
 
-        class Float
+        class Float < Type
           def type_cast(value)
             return if value.nil?
 
@@ -116,7 +124,7 @@ module ActiveRecord
           end
         end
 
-        class Decimal
+        class Decimal < Type
           def type_cast(value)
             return if value.nil?
 
@@ -124,7 +132,7 @@ module ActiveRecord
           end
         end
 
-        class Hstore
+        class Hstore < Type
           def type_cast(value)
             return if value.nil?
 
diff --git a/activerecord/lib/active_record/inheritance.rb b/activerecord/lib/active_record/inheritance.rb
index 1f5b3b2e79..2c766411a0 100644
--- a/activerecord/lib/active_record/inheritance.rb
+++ b/activerecord/lib/active_record/inheritance.rb
@@ -77,6 +77,7 @@ module ActiveRecord
             IdentityMap.add(instance)
           end
         else
+          column_types = sti_class.decorate_columns(column_types)
           instance = sti_class.allocate.init_with('attributes' => record,
                                                   'column_types' => column_types)
         end
diff --git a/activerecord/lib/active_record/model_schema.rb b/activerecord/lib/active_record/model_schema.rb
index 5486e192e4..b8764217d3 100644
--- a/activerecord/lib/active_record/model_schema.rb
+++ b/activerecord/lib/active_record/model_schema.rb
@@ -206,12 +206,24 @@ module ActiveRecord
         @columns_hash ||= Hash[columns.map { |c| [c.name, c] }]
       end
 
-      def column_types
-        @column_types ||= columns_hash.dup.tap { |x|
-          serialized_attributes.keys.each do |key|
-            x[key] = AttributeMethods::Serialization::Type.new(x[key])
+      def column_types # :nodoc:
+        @column_types ||= decorate_columns(columns_hash.dup)
+      end
+
+      def decorate_columns(columns_hash) # :nodoc:
+        return if columns_hash.empty?
+
+        serialized_attributes.keys.each do |key|
+          columns_hash[key] = AttributeMethods::Serialization::Type.new(columns_hash[key])
+        end
+
+        columns_hash.each do |name, col|
+          if create_time_zone_conversion_attribute?(name, col)
+            columns_hash[name] = AttributeMethods::TimeZoneConversion::Type.new(col)
           end
-        }
+        end
+
+        columns_hash
       end
 
       # Returns a hash where the keys are column names and the values are