Extract an explicit type caster class

activerecord/lib/active_record/attributes.rb

@@ -122,6 +122,7 @@ def add_user_provided_columns(schema_columns)
       end
 
       def clear_caches_calculated_from_columns
+        @arel_table = nil
         @attributes_builder = nil
         @column_names = nil
         @column_types = nil

activerecord/lib/active_record/base.rb

@@ -22,6 +22,7 @@
 require 'active_record/explain_subscriber'
 require 'active_record/relation/delegation'
 require 'active_record/attributes'
+require 'active_record/type_caster'
 
 module ActiveRecord #:nodoc:
   # = Active Record

activerecord/lib/active_record/core.rb

@@ -235,7 +235,7 @@ def ===(object)
       #     scope :published_and_commented, -> { published.and(self.arel_table[:comments_count].gt(0)) }
       #   end
       def arel_table # :nodoc:
-        @arel_table ||= Arel::Table.new(table_name, type_caster: self)
+        @arel_table ||= Arel::Table.new(table_name, type_caster: type_caster)
       end
 
       # Returns the Arel engine.
@@ -252,12 +252,6 @@ def predicate_builder # :nodoc:
         @predicate_builder ||= PredicateBuilder.new(table_metadata)
       end
 
-      def type_cast_for_database(attribute_name, value)
-        return value if value.is_a?(Arel::Nodes::BindParam)
-        type = type_for_attribute(attribute_name.to_s)
-        type.type_cast_for_database(value)
-      end
-
       private
 
       def relation # :nodoc:
@@ -273,6 +267,10 @@ def relation # :nodoc:
       def table_metadata # :nodoc:
         TableMetadata.new(self, arel_table)
       end
+
+      def type_caster # :nodoc:
+        TypeCaster::Map.new(self)
+      end
     end
 
     # New objects can be instantiated as either empty (pass no construction parameter) or pre-set with

activerecord/lib/active_record/model_schema.rb

@@ -298,6 +298,7 @@ def reset_column_information
         connection.schema_cache.clear_table_cache!(table_name) if table_exists?
 
         @arel_engine        = nil
+        @arel_table         = nil
         @column_names       = nil
         @column_types       = nil
         @content_columns    = nil

activerecord/lib/active_record/table_metadata.rb

@@ -34,7 +34,7 @@ def associated_table(table_name)
         association_klass = association.klass
         arel_table = association_klass.arel_table
       else
-        type_caster = ConnectionAdapterTypeCaster.new(klass.connection, table_name)
+        type_caster = TypeCaster::Connection.new(klass.connection, table_name)
         association_klass = nil
         arel_table = Arel::Table.new(table_name, type_caster: type_caster)
       end
@@ -50,35 +50,4 @@ def polymorphic_association?
 
     attr_reader :klass, :arel_table, :association
   end
-
-  class ConnectionAdapterTypeCaster
-    def initialize(connection, table_name)
-      @connection = connection
-      @table_name = table_name
-    end
-
-    def type_cast_for_database(attribute_name, value)
-      return value if value.is_a?(Arel::Nodes::BindParam)
-      type = type_for(attribute_name)
-      type.type_cast_for_database(value)
-    end
-
-    protected
-
-    attr_reader :connection, :table_name
-
-    private
-
-    def type_for(attribute_name)
-      if connection.schema_cache.table_exists?(table_name)
-        column_for(attribute_name).cast_type
-      else
-        Type::Value.new
-      end
-    end
-
-    def column_for(attribute_name)
-      connection.schema_cache.columns_hash(table_name)[attribute_name.to_s]
-    end
-  end
 end

activerecord/lib/active_record/type_caster.rb

+require 'active_record/type_caster/map'
+require 'active_record/type_caster/connection'
+
+module ActiveRecord
+  module TypeCaster
+  end
+end

activerecord/lib/active_record/type_caster/connection.rb

+module ActiveRecord
+  module TypeCaster
+    class Connection
+      def initialize(connection, table_name)
+        @connection = connection
+        @table_name = table_name
+      end
+
+      def type_cast_for_database(attribute_name, value)
+        return value if value.is_a?(Arel::Nodes::BindParam)
+        type = type_for(attribute_name)
+        type.type_cast_for_database(value)
+      end
+
+      protected
+
+      attr_reader :connection, :table_name
+
+      private
+
+      def type_for(attribute_name)
+        if connection.schema_cache.table_exists?(table_name)
+          column_for(attribute_name).cast_type
+        else
+          Type::Value.new
+        end
+      end
+
+      def column_for(attribute_name)
+        connection.schema_cache.columns_hash(table_name)[attribute_name.to_s]
+      end
+    end
+  end
+end

activerecord/lib/active_record/type_caster/map.rb

+module ActiveRecord
+  module TypeCaster
+    class Map
+      def initialize(types)
+        @types = types
+      end
+
+      def type_cast_for_database(attr_name, value)
+        return value if value.is_a?(Arel::Nodes::BindParam)
+        type = types.type_for_attribute(attr_name.to_s)
+        type.type_cast_for_database(value)
+      end
+
+      protected
+
+      attr_reader :types
+    end
+  end
+end