Added preliminary support for join models [DHH] Added preliminary sup…

…port for polymorphic associations [DHH] Refactored associations to use reflections to get DRYer, beware, major refactoring -- double check before deploying anything with this (all tests pass, but..)

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3213 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

@@ -1,5 +1,9 @@
 *SVN*
 
+* Added preliminary support for polymorphic associations [DHH]
+
+* Added preliminary support for join models [DHH]
+
 * Allow validate_uniqueness_of to be scoped by more than just one column.  #1559. [jeremy@jthopple.com, Marcel Molina Jr.]
 
 * Firebird: active? and reconnect! methods for handling stale connections.  #428 [Ken Kunz <kennethkunz@gmail.com>]

activerecord/lib/active_record.rb

@@ -38,10 +38,10 @@
 require 'active_record/observer'
 require 'active_record/validations'
 require 'active_record/callbacks'
+require 'active_record/reflection'
 require 'active_record/associations'
 require 'active_record/aggregations'
 require 'active_record/transactions'
-require 'active_record/reflection'
 require 'active_record/timestamp'
 require 'active_record/acts/list'
 require 'active_record/acts/tree'

activerecord/lib/active_record/aggregations.rb

@@ -1,7 +1,6 @@
 module ActiveRecord
   module Aggregations # :nodoc:
-    def self.append_features(base)
-      super
+    def self.included(base)
       base.extend(ClassMethods)
     end
 
@@ -128,6 +127,8 @@ def composed_of(part_id, options = {})
 
         reader_method(name, class_name, mapping)
         writer_method(name, class_name, mapping)
+
+        create_reflection(:composed_of, part_id, options, self)
       end
 
       private

activerecord/lib/active_record/associations/association_collection.rb

@@ -18,6 +18,7 @@ def reset
       def <<(*records)
         result = true
         load_target
+
         @owner.transaction do
           flatten_deeper(records).each do |record|
             raise_on_type_mismatch(record)
@@ -28,7 +29,7 @@ def <<(*records)
           end
         end
 
-        result and self
+        result && self
       end
 
       alias_method :push, :<<
@@ -60,11 +61,13 @@ def delete(*records)
       # Removes all records from this association.  Returns +self+ so method calls may be chained.
       def clear
         return self if length.zero? # forces load_target if hasn't happened already
-        if @options[:exclusively_dependent]
+
+        if @reflection.options[:exclusively_dependent]
           destroy_all
         else          
           delete_all
         end
+
         self
       end
 
@@ -124,14 +127,6 @@ def replace(other_array)
       end
 
       private
-        def raise_on_type_mismatch(record)
-          raise ActiveRecord::AssociationTypeMismatch, "#{@association_class} expected, got #{record.class}" unless record.is_a?(@association_class)
-        end
-
-        def target_obsolete?
-          false
-        end
-
         # Array#flatten has problems with recursive arrays. Going one level deeper solves the majority of the problems.
         def flatten_deeper(array)
           array.collect { |element| element.respond_to?(:flatten) ? element.flatten : element }.flatten
@@ -155,8 +150,8 @@ def callback(method, record)
         end
 
         def callbacks_for(callback_name)
-          full_callback_name = "#{callback_name.to_s}_for_#{@association_name.to_s}"
-          @owner.class.read_inheritable_attribute(full_callback_name.to_sym) or []
+          full_callback_name = "#{callback_name}_for_#{@reflection.name}"
+          @owner.class.read_inheritable_attribute(full_callback_name.to_sym) || []
         end
 
     end

activerecord/lib/active_record/associations/association_proxy.rb

@@ -5,15 +5,9 @@ class AssociationProxy #:nodoc:
       alias_method :proxy_extend, :extend
       instance_methods.each { |m| undef_method m unless m =~ /(^__|^nil\?|^proxy_respond_to\?|^proxy_extend|^send)/ }
 
-      def initialize(owner, association_name, association_class_name, association_class_primary_key_name, options)
-        @owner = owner
-        @options = options
-        @association_name = association_name
-        @association_class = eval(association_class_name, nil, __FILE__, __LINE__)
-        @association_class_primary_key_name = association_class_primary_key_name
-
-        proxy_extend(options[:extend]) if options[:extend]
-
+      def initialize(owner, reflection)
+        @owner, @reflection = owner, reflection
+        proxy_extend(reflection.options[:extend]) if reflection.options[:extend]
         reset
       end
 
@@ -28,6 +22,11 @@ def ===(other)
         other === @target
       end
 
+      def reset
+        @target = nil
+        @loaded = false
+      end
+
       def reload
         reset
         load_target
@@ -45,14 +44,14 @@ def target
         @target
       end
 
-      def target=(t)
-        @target = t
-        @loaded = true
+      def target=(target)
+        @target = target
+        loaded
       end
 
       protected
         def dependent?
-          @options[:dependent] || false
+          @reflection.options[:dependent] || false
         end
 
         def quoted_record_ids(records)
@@ -68,7 +67,7 @@ def interpolate_sql(sql, record = nil)
         end
 
         def sanitize_sql(sql)
-          @association_class.send(:sanitize_sql, sql)
+          @reflection.klass.send(:sanitize_sql, sql)
         end
 
         def extract_options_from_args!(args)
@@ -84,13 +83,14 @@ def method_missing(method, *args, &block)
         def load_target
           if !@owner.new_record? || foreign_key_present
             begin
-              @target = find_target if not loaded?
+              @target = find_target if !loaded?
             rescue ActiveRecord::RecordNotFound
               reset
             end
           end
-          @loaded = true if @target
-          @target
+
+          loaded if target
+          target
         end
 
         # Can be overwritten by associations that might have the foreign key available for an association without
@@ -100,7 +100,9 @@ def foreign_key_present
         end
 
         def raise_on_type_mismatch(record)
-          raise ActiveRecord::AssociationTypeMismatch, "#{@association_class} expected, got #{record.class}" unless record.is_a?(@association_class)
+          unless record.is_a?(@reflection.klass)
+            raise ActiveRecord::AssociationTypeMismatch, "#{@reflection.class_name} expected, got #{record.class}"
+          end
         end
     end
   end

activerecord/lib/active_record/associations/belongs_to_association.rb

@@ -1,41 +1,27 @@
 module ActiveRecord
   module Associations
     class BelongsToAssociation < AssociationProxy #:nodoc:
-      def initialize(owner, association_name, association_class_name, association_class_primary_key_name, options)
-        super        
-        construct_sql        
-      end
-
-      def reset
-        @target = nil
-        @loaded = false
-      end
-
       def create(attributes = {})
-        record = @association_class.create(attributes)
-        replace(record, true)
-        record
+        replace(@reflection.klass.create(attributes))
       end
 
       def build(attributes = {})
-        record = @association_class.new(attributes)
-        replace(record, true)
-        record
+        replace(@reflection.klass.new(attributes))
       end
 
-      def replace(obj, dont_save = false)
-        if obj.nil?
-          @target = @owner[@association_class_primary_key_name] = nil
+      def replace(record)
+        if record.nil?
+          @target = @owner[@reflection.primary_key_name] = nil
         else
-          raise_on_type_mismatch(obj) unless obj.nil?
+          raise_on_type_mismatch(record)
 
-          @target = (AssociationProxy === obj ? obj.target : obj)
-          @owner[@association_class_primary_key_name] = obj.id unless obj.new_record?
+          @target = (AssociationProxy === record ? record.target : record)
+          @owner[@reflection.primary_key_name] = record.id unless record.new_record?
           @updated = true
         end
-        @loaded = true
 
-        return (@target.nil? ? nil : self)
+        loaded
+        record
       end
 
       def updated?
@@ -44,27 +30,15 @@ def updated?
 
       private
         def find_target
-          if @options[:conditions]
-            @association_class.find(
-              @owner[@association_class_primary_key_name], 
-              :conditions => interpolate_sql(@options[:conditions]),
-              :include    => @options[:include]
-            )
-          else
-            @association_class.find(@owner[@association_class_primary_key_name], :include => @options[:include])
-          end
+          @reflection.klass.find(
+            @owner[@reflection.primary_key_name], 
+            :conditions => @reflection.options[:conditions] ? interpolate_sql(@reflection.options[:conditions]) : nil,
+            :include    => @reflection.options[:include]
+          )
         end
 
         def foreign_key_present
-          !@owner[@association_class_primary_key_name].nil?
-        end
-
-        def target_obsolete?
-          @owner[@association_class_primary_key_name] != @target.id
-        end
-
-        def construct_sql
-          @finder_sql = "#{@association_class.table_name}.#{@association_class.primary_key} = #{@owner.id}"
+          !@owner[@reflection.primary_key_name].nil?
         end
     end
   end

activerecord/lib/active_record/associations/belongs_to_polymorphic_association.rb

@@ -1,69 +1,49 @@
 module ActiveRecord
   module Associations
-    class BelongsToPolymorphicAssociation < BelongsToAssociation #:nodoc:
-      def initialize(owner, association_name, association_class_name, association_class_primary_key_name, options)
-        @owner = owner
-        @options = options
-        @association_name = association_name
-        @association_class_primary_key_name = association_class_primary_key_name
-
-        proxy_extend(options[:extend]) if options[:extend]
-
-        reset
-      end
-
-      def create(attributes = {})
-        raise ActiveRecord::ActiveRecordError, "Can't create an abstract polymorphic object"
-      end
-
-      def build(attributes = {})
-        raise ActiveRecord::ActiveRecordError, "Can't build an abstract polymorphic object"
-      end
-
-      def replace(obj, dont_save = false)
-        if obj.nil?
-          @target = @owner[@association_class_primary_key_name] = @owner[@options[:foreign_type]] = nil
+    class BelongsToPolymorphicAssociation < AssociationProxy #:nodoc:
+      def replace(record)
+        if record.nil?
+          @target = @owner[@reflection.primary_key_name] = @owner[@reflection.options[:foreign_type]] = nil
         else
-          @target = (AssociationProxy === obj ? obj.target : obj)
+          @target = (AssociationProxy === record ? record.target : record)
 
-          unless obj.new_record?
-            @owner[@association_class_primary_key_name] = obj.id
-            @owner[@options[:foreign_type]] = ActiveRecord::Base.send(:class_name_of_active_record_descendant, obj.class).to_s
+          unless record.new_record?
+            @owner[@reflection.primary_key_name] = record.id
+            @owner[@reflection.options[:foreign_type]] = ActiveRecord::Base.send(:class_name_of_active_record_descendant, record.class).to_s
           end
 
           @updated = true
         end
 
-        @loaded = true
+        loaded
+        record
+      end
 
-        return (@target.nil? ? nil : self)
+      def updated?
+        @updated
       end
-      
+
       private
         def find_target
           return nil if association_class.nil?
 
-          if @options[:conditions]
+          if @reflection.options[:conditions]
             association_class.find(
-              @owner[@association_class_primary_key_name], 
-              :conditions => interpolate_sql(@options[:conditions]),
-              :include    => @options[:include]
+              @owner[@reflection.primary_key_name], 
+              :conditions => interpolate_sql(@reflection.options[:conditions]),
+              :include    => @reflection.options[:include]
             )
           else
-            association_class.find(@owner[@association_class_primary_key_name], :include => @options[:include])
+            association_class.find(@owner[@reflection.primary_key_name], :include => @reflection.options[:include])
           end
         end
 
         def foreign_key_present
-          !@owner[@association_class_primary_key_name].nil?
+          !@owner[@reflection.primary_key_name].nil?
         end
 
-        def target_obsolete?
-          @owner[@association_class_primary_key_name] != @target.id
-        end
-
         def association_class
-          @owner[@options[:foreign_type]] ? @owner[@options[:foreign_type]].constantize : nil
+          @owner[@reflection.options[:foreign_type]] ? @owner[@reflection.options[:foreign_type]].constantize : nil
         end
     end
   end