Refactoring attributes/types [#3348 state:resolved]

Signed-off-by: Joshua Peek <josh@joshpeek.com>

activerecord/lib/active_record.rb

@@ -51,6 +51,7 @@ def self.load_all!
   autoload :AssociationPreload, 'active_record/association_preload'
   autoload :Associations, 'active_record/associations'
   autoload :AttributeMethods, 'active_record/attribute_methods'
+  autoload :Attributes, 'active_record/attributes'
   autoload :AutosaveAssociation, 'active_record/autosave_association'
   autoload :Relation, 'active_record/relation'
   autoload :Base, 'active_record/base'
@@ -74,6 +75,7 @@ def self.load_all!
   autoload :TestCase, 'active_record/test_case'
   autoload :Timestamp, 'active_record/timestamp'
   autoload :Transactions, 'active_record/transactions'
+  autoload :Types, 'active_record/types'
   autoload :Validator, 'active_record/validator'
   autoload :Validations, 'active_record/validations'
 
@@ -87,6 +89,20 @@ module AttributeMethods
     autoload :Write, 'active_record/attribute_methods/write'
   end
 
+  module Attributes
+    autoload :Aliasing, 'active_record/attributes/aliasing'
+    autoload :Store, 'active_record/attributes/store'
+    autoload :Typecasting, 'active_record/attributes/typecasting'
+  end
+
+  module Type
+    autoload :Number, 'active_record/types/number'
+    autoload :Object, 'active_record/types/object'
+    autoload :Serialize, 'active_record/types/serialize'
+    autoload :TimeWithZone, 'active_record/types/time_with_zone'
+    autoload :Unknown, 'active_record/types/unknown'
+  end
+
   module Locking
     autoload :Optimistic, 'active_record/locking/optimistic'
     autoload :Pessimistic, 'active_record/locking/pessimistic'

activerecord/lib/active_record/attribute_methods/before_type_cast.rb

@@ -8,25 +8,18 @@ module BeforeTypeCast
       end
 
       def read_attribute_before_type_cast(attr_name)
-        @attributes[attr_name]
+        _attributes.without_typecast[attr_name]
       end
 
       # Returns a hash of attributes before typecasting and deserialization.
       def attributes_before_type_cast
-        self.attribute_names.inject({}) do |attrs, name|
-          attrs[name] = read_attribute_before_type_cast(name)
-          attrs
-        end
+        _attributes.without_typecast
       end
 
       private
         # Handle *_before_type_cast for method_missing.
         def attribute_before_type_cast(attribute_name)
-          if attribute_name == 'id'
-            read_attribute_before_type_cast(self.class.primary_key)
-          else
-            read_attribute_before_type_cast(attribute_name)
-          end
+          read_attribute_before_type_cast(attribute_name)
         end
     end
   end

activerecord/lib/active_record/attribute_methods/query.rb

@@ -8,23 +8,7 @@ module Query
       end
 
       def query_attribute(attr_name)
-        unless value = read_attribute(attr_name)
-          false
-        else
-          column = self.class.columns_hash[attr_name]
-          if column.nil?
-            if Numeric === value || value !~ /[^0-9]/
-              !value.to_i.zero?
-            else
-              return false if ActiveRecord::ConnectionAdapters::Column::FALSE_VALUES.include?(value)
-              !value.blank?
-            end
-          elsif column.number?
-            !value.zero?
-          else
-            !value.blank?
-          end
-        end
+        _attributes.has?(attr_name)
       end
 
       private
@@ -35,3 +19,5 @@ def attribute?(attribute_name)
     end
   end
 end
+
+

activerecord/lib/active_record/attribute_methods/read.rb

@@ -37,30 +37,20 @@ def cache_attribute?(attr_name)
 
         protected
           def define_method_attribute(attr_name)
-            if self.serialized_attributes[attr_name]
-              define_read_method_for_serialized_attribute(attr_name)
-            else
-              define_read_method(attr_name.to_sym, attr_name, columns_hash[attr_name])
-            end
+            define_read_method(attr_name.to_sym, attr_name, columns_hash[attr_name])
 
             if attr_name == primary_key && attr_name != "id"
               define_read_method(:id, attr_name, columns_hash[attr_name])
             end
           end
 
         private
-          # Define read method for serialized attribute.
-          def define_read_method_for_serialized_attribute(attr_name)
-            generated_attribute_methods.module_eval("def #{attr_name}; unserialize_attribute('#{attr_name}'); end", __FILE__, __LINE__)
-          end
 
           # Define an attribute reader method.  Cope with nil column.
           def define_read_method(symbol, attr_name, column)
-            cast_code = column.type_cast_code('v') if column
-            access_code = cast_code ? "(v=@attributes['#{attr_name}']) && #{cast_code}" : "@attributes['#{attr_name}']"
-
+            access_code = "_attributes['#{attr_name}']"
             unless attr_name.to_s == self.primary_key.to_s
-              access_code = access_code.insert(0, "missing_attribute('#{attr_name}', caller) unless @attributes.has_key?('#{attr_name}'); ")
+              access_code = access_code.insert(0, "missing_attribute('#{attr_name}', caller) unless _attributes.key?('#{attr_name}'); ")
             end
 
             if cache_attribute?(attr_name)
@@ -73,38 +63,7 @@ def define_read_method(symbol, attr_name, column)
       # Returns the value of the attribute identified by <tt>attr_name</tt> after it has been typecast (for example,
       # "2004-12-12" in a data column is cast to a date object, like Date.new(2004, 12, 12)).
       def read_attribute(attr_name)
-        attr_name = attr_name.to_s
-        attr_name = self.class.primary_key if attr_name == 'id'
-        if !(value = @attributes[attr_name]).nil?
-          if column = column_for_attribute(attr_name)
-            if unserializable_attribute?(attr_name, column)
-              unserialize_attribute(attr_name)
-            else
-              column.type_cast(value)
-            end
-          else
-            value
-          end
-        else
-          nil
-        end
-      end
-
-      # Returns true if the attribute is of a text column and marked for serialization.
-      def unserializable_attribute?(attr_name, column)
-        column.text? && self.class.serialized_attributes[attr_name]
-      end
-
-      # Returns the unserialized object of the attribute.
-      def unserialize_attribute(attr_name)
-        unserialized_object = object_from_yaml(@attributes[attr_name])
-
-        if unserialized_object.is_a?(self.class.serialized_attributes[attr_name]) || unserialized_object.nil?
-          @attributes.frozen? ? unserialized_object : @attributes[attr_name] = unserialized_object
-        else
-          raise SerializationTypeMismatch,
-            "#{attr_name} was supposed to be a #{self.class.serialized_attributes[attr_name]}, but was a #{unserialized_object.class.to_s}"
-        end
+        _attributes[attr_name]
       end
 
       private

activerecord/lib/active_record/attribute_methods/time_zone_conversion.rb

@@ -12,48 +12,20 @@ module TimeZoneConversion
       end
 
       module ClassMethods
+
+        def cache_attribute?(attr_name)
+          time_zone_aware?(attr_name) || super
+        end
+
         protected
-          # Defined for all +datetime+ and +timestamp+ attributes when +time_zone_aware_attributes+ are enabled.
-          # This enhanced read method automatically converts the UTC time stored in the database to the time zone stored in Time.zone.
-          def define_method_attribute(attr_name)
-            if create_time_zone_conversion_attribute?(attr_name, columns_hash[attr_name])
-              method_body = <<-EOV
-                def #{attr_name}(reload = false)
-                  cached = @attributes_cache['#{attr_name}']
-                  return cached if cached && !reload
-                  time = read_attribute('#{attr_name}')
-                  @attributes_cache['#{attr_name}'] = time.acts_like?(:time) ? time.in_time_zone : time
-                end
-              EOV
-              generated_attribute_methods.module_eval(method_body, __FILE__, __LINE__)
-            else
-              super
-            end
-          end
 
-          # Defined for all +datetime+ and +timestamp+ attributes when +time_zone_aware_attributes+ are enabled.
-          # This enhanced write method will automatically convert the time passed to it to the zone stored in Time.zone.
-          def define_method_attribute=(attr_name)
-            if create_time_zone_conversion_attribute?(attr_name, columns_hash[attr_name])
-              method_body = <<-EOV
-                def #{attr_name}=(time)
-                  unless time.acts_like?(:time)
-                    time = time.is_a?(String) ? Time.zone.parse(time) : time.to_time rescue time
-                  end
-                  time = time.in_time_zone rescue nil if time
-                  write_attribute(:#{attr_name}, time)
-                end
-              EOV
-              generated_attribute_methods.module_eval(method_body, __FILE__, __LINE__)
-            else
-              super
-            end
+          def time_zone_aware?(attr_name)
+            column = columns_hash[attr_name]
+            time_zone_aware_attributes &&
+              !skip_time_zone_conversion_for_attributes.include?(attr_name.to_sym) &&
+                [:datetime, :timestamp].include?(column.type)
           end
 
-        private
-          def create_time_zone_conversion_attribute?(name, column)
-            time_zone_aware_attributes && !skip_time_zone_conversion_for_attributes.include?(name.to_sym) && [:datetime, :timestamp].include?(column.type)
-          end
       end
     end
   end

activerecord/lib/active_record/attribute_methods/write.rb

@@ -17,14 +17,9 @@ def define_method_attribute=(attr_name)
       # Updates the attribute identified by <tt>attr_name</tt> with the specified +value+. Empty strings for fixnum and float
       # columns are turned into +nil+.
       def write_attribute(attr_name, value)
-        attr_name = attr_name.to_s
-        attr_name = self.class.primary_key if attr_name == 'id'
+        attr_name = _attributes.unalias(attr_name)
         @attributes_cache.delete(attr_name)
-        if (column = column_for_attribute(attr_name)) && column.number?
-          @attributes[attr_name] = convert_number_column_value(value)
-        else
-          @attributes[attr_name] = value
-        end
+        _attributes[attr_name] = value
       end
 
       private

activerecord/lib/active_record/attributes.rb

@@ -0,0 +1,37 @@
+module ActiveRecord
+  module Attributes
+
+     # Returns true if the given attribute is in the attributes hash
+     def has_attribute?(attr_name)
+       _attributes.key?(attr_name)
+     end
+
+     # Returns an array of names for the attributes available on this object sorted alphabetically.
+     def attribute_names
+       _attributes.keys.sort!
+     end
+
+     # Returns a hash of all the attributes with their names as keys and the values of the attributes as values.
+     def attributes
+       attributes = _attributes.dup
+       attributes.typecast! unless _attributes.frozen?
+       attributes.to_h
+     end
+
+     protected
+
+     # Not to be confused with the public #attributes method, which returns a typecasted Hash.
+     def _attributes
+       @attributes
+     end
+
+     def initialize_attribute_store(merge_attributes = nil)
+       @attributes = ActiveRecord::Attributes::Store.new
+       @attributes.merge!(merge_attributes) if merge_attributes
+       @attributes.types.merge!(self.class.attribute_types)
+       @attributes.aliases.merge!('id' => self.class.primary_key) unless 'id' == self.class.primary_key
+       @attributes
+     end
+
+  end
+end

activerecord/lib/active_record/attributes/aliasing.rb

@@ -0,0 +1,42 @@
+module ActiveRecord
+  module Attributes
+    module Aliasing
+      # Allows access to keys using aliased names.
+      #
+      # Example:
+      # class Attributes < Hash
+      #   include Aliasing
+      # end
+      #
+      # attributes = Attributes.new
+      # attributes.aliases['id'] = 'fancy_primary_key'
+      # attributes['fancy_primary_key'] = 2020
+      #
+      # attributes['id']
+      # => 2020
+      #
+      # Additionally, symbols are always aliases of strings:
+      # attributes[:fancy_primary_key]
+      # => 2020
+      #
+      def [](key)
+        super(unalias(key))
+      end
+
+      def []=(key, value)
+        super(unalias(key), value)
+      end
+
+      def aliases
+        @aliases ||= {}
+      end
+
+      def unalias(key)
+        key = key.to_s
+        aliases[key] || key
+      end
+
+    end
+  end
+end
+

activerecord/lib/active_record/attributes/store.rb

@@ -0,0 +1,15 @@
+module ActiveRecord
+  module Attributes
+    class Store < Hash
+      include ActiveRecord::Attributes::Typecasting
+      include ActiveRecord::Attributes::Aliasing
+
+      # Attributes not mapped to a column are handled using Type::Unknown,
+      # which enables boolean typecasting for unmapped keys.
+      def types
+        @types ||= Hash.new(Type::Unknown.new)
+      end
+
+    end
+  end
+end