Added support for calling constrained class methods on has_many and has_and_belongs_to_many collections #1764 [Tobias Luetke]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@1894 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

6 files changed, 66 insertions, 53 deletions

diff --git a/activerecord/lib/active_record/associations/association_collection.rb b/activerecord/lib/active_record/associations/association_collection.rb
index 140a12eacf..3b7f2df870 100644
--- a/activerecord/lib/active_record/associations/association_collection.rb
+++ b/activerecord/lib/active_record/associations/association_collection.rb
@@ -107,6 +107,15 @@ module ActiveRecord
       end
 
       private
+      
+        def method_missing(method, *args, &block)
+          if @target.respond_to?(method) or (not @association_class.respond_to?(method) and Class.respond_to?(method))
+            super
+          else
+            @association_class.constrain( :conditions => @finder_sql, :joins => @join_sql) { @association_class.send(method, *args, &block) }
+          end
+        end
+              
         def raise_on_type_mismatch(record)
           raise ActiveRecord::AssociationTypeMismatch, "#{@association_class} expected, got #{record.class}" unless record.is_a?(@association_class)
         end
diff --git a/activerecord/lib/active_record/associations/association_proxy.rb b/activerecord/lib/active_record/associations/association_proxy.rb
index f80a7e996c..ed34b1df6c 100644
--- a/activerecord/lib/active_record/associations/association_proxy.rb
+++ b/activerecord/lib/active_record/associations/association_proxy.rb
@@ -19,11 +19,6 @@ module ActiveRecord
         load_target
       end
 
-      def method_missing(symbol, *args, &block)
-        load_target
-        @target.send(symbol, *args, &block)
-      end
-
       def respond_to?(symbol, include_priv = false)
         proxy_respond_to?(symbol, include_priv) || (load_target && @target.respond_to?(symbol, include_priv))
       end
@@ -44,7 +39,7 @@ module ActiveRecord
         @target = t
         @loaded = true
       end
-
+      
       protected
         def dependent?
           @options[:dependent] || false
@@ -69,8 +64,14 @@ module ActiveRecord
         def extract_options_from_args!(args)
           @owner.send(:extract_options_from_args!, args)
         end
-
+        
       private
+        
+        def method_missing(method, *args, &block)
+          load_target
+          @target.send(method, *args, &block)
+        end
+
         def load_target
           if !@owner.new_record? || foreign_key_present
             begin
diff --git a/activerecord/lib/active_record/associations/belongs_to_association.rb b/activerecord/lib/active_record/associations/belongs_to_association.rb
index b142a13153..60c31ce486 100644
--- a/activerecord/lib/active_record/associations/belongs_to_association.rb
+++ b/activerecord/lib/active_record/associations/belongs_to_association.rb
@@ -1,6 +1,12 @@
 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
@@ -31,6 +37,9 @@ module ActiveRecord
 
         return (@target.nil? ? nil : self)
       end
+      
+      protected
+
 
       private
         def find_target
@@ -48,9 +57,9 @@ module ActiveRecord
         def target_obsolete?
           @owner[@association_class_primary_key_name] != @target.id
         end
-
+        
         def construct_sql
-          # no sql to construct
+          @finder_sql = "#{@association_class.table_name}.#{@association_class.primary_key} = #{@owner.id}"
         end
     end
   end
diff --git a/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb b/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
index 107f3ef12c..7d85a2268b 100644
--- a/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
@@ -42,19 +42,15 @@ module ActiveRecord
       def find_first
         load_target.first
       end
-
+      
       def find(*args)
-        # Return an Array if multiple ids are given.
-        expects_array = args.first.kind_of?(Array)
-
-        ids = args.flatten.compact.uniq
-
-        # If no block is given, raise RecordNotFound.
-        if ids.empty?
-          raise RecordNotFound, "Couldn't find #{@association_class.name} without an ID"
+        options = Base.send(:extract_options_from_args!, args)
 
         # If using a custom finder_sql, scan the entire collection.
-        elsif @options[:finder_sql]
+        if @options[:finder_sql]
+          expects_array = args.first.kind_of?(Array)
+          ids = args.flatten.compact.uniq
+
           if ids.size == 1
             id = ids.first
             record = load_target.detect { |record| id == record.id }
@@ -62,22 +58,25 @@ module ActiveRecord
           else
             load_target.select { |record| ids.include?(record.id) }
           end
-
-        # Otherwise, construct a query.
         else
-          ids_list = ids.map { |id| @owner.send(:quote, id) }.join(',')
-          records = find_target(@finder_sql.sub(/(ORDER BY|$)/, " AND j.#{@association_foreign_key} IN (#{ids_list}) \\1"))
-          if records.size == ids.size
-            if ids.size == 1 and !expects_array
-              records.first
-            else
-              records
-            end
-          else
-            raise RecordNotFound, "Couldn't find #{@association_class.name} with ID in (#{ids_list})"
+          conditions = "#{@finder_sql}"
+          if sanitized_conditions = sanitize_sql(options[:conditions])
+            conditions << " AND #{sanitized_conditions}"
+          end
+          options[:conditions] = conditions
+          options[:joins] = @join_sql
+
+          if options[:order] && @options[:order]
+            options[:order] = "#{options[:order]}, #{@options[:order]}"
+          elsif @options[:order]
+            options[:order] = @options[:order]
           end
+
+          # Pass through args exactly as we received them.
+          args << options
+          @association_class.find(*args)
         end
-      end
+      end      
 
       def push_with_attributes(record, join_attributes = {})
         raise_on_type_mismatch(record)
@@ -96,11 +95,17 @@ module ActiveRecord
       end
       
       protected
-        def find_target(sql = @finder_sql)
-          records = @association_class.find_by_sql(sql)
+        def find_target(sql = nil)
+          
+          if sql
+            records = @association_class.find_by_sql(sql) if sql
+          else
+            records = find(:all)
+          end
+          
           @options[:uniq] ? uniq(records) : records
         end
-
+        
         def count_records
           load_target.size
         end
@@ -152,28 +157,17 @@ module ActiveRecord
 
         def construct_sql
           interpolate_sql_options!(@options, :finder_sql)
-          
+
           if @options[:finder_sql]
             @finder_sql = @options[:finder_sql]
           else
-            @finder_sql = 
-              "SELECT t.*, j.* FROM #{@join_table} j, #{@association_table_name} t " +
-              "WHERE t.#{@association_class.primary_key} = j.#{@association_foreign_key} AND " +
-              "j.#{@association_class_primary_key_name} = #{@owner.quoted_id} "
-            
+            @finder_sql = "#{@association_class_primary_key_name} = #{@owner.quoted_id} "
             @finder_sql << " AND #{interpolate_sql(@options[:conditions])}" if @options[:conditions]
-
-            unless @association_class.descends_from_active_record?
-              type_condition = @association_class.send(:subclasses).inject("t.#{@association_class.inheritance_column} = '#{@association_class.name.demodulize}' ") do |condition, subclass| 
-                condition << "OR t.#{@association_class.inheritance_column} = '#{subclass.name.demodulize}' "
-              end
-
-              @finder_sql << " AND (#{type_condition})"
-            end
-	
-            @finder_sql << " ORDER BY #{@order}" if @order
           end
+          
+          @join_sql = "LEFT JOIN #{@join_table} ON #{@association_class.table_name}.#{@association_class.primary_key} = #{@join_table}.#{@association_foreign_key}"
         end
+        
     end
   end
 end
diff --git a/activerecord/lib/active_record/associations/has_many_association.rb b/activerecord/lib/active_record/associations/has_many_association.rb
index 21879adb77..fdeadfc181 100644
--- a/activerecord/lib/active_record/associations/has_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_association.rb
@@ -91,7 +91,7 @@ module ActiveRecord
         @target = []
         self
       end
-
+      
       protected
         def find_target
           find_all
diff --git a/activerecord/lib/active_record/associations/has_one_association.rb b/activerecord/lib/active_record/associations/has_one_association.rb
index 4a6e85c8ee..1550db69b5 100644
--- a/activerecord/lib/active_record/associations/has_one_association.rb
+++ b/activerecord/lib/active_record/associations/has_one_association.rb
@@ -54,7 +54,7 @@ module ActiveRecord
           return (obj.nil? ? nil : self)
         end
       end
-      
+            
       private
         def find_target
           @association_class.find(:first, :conditions => @finder_sql, :order => @options[:order])