made .find() and class method delegation work on :through relations

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3325 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

2 files changed, 35 insertions, 4 deletions

diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index 3a3966bb8a..ea338e4658 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -1,6 +1,14 @@
 module ActiveRecord
   module Associations
     class HasManyThroughAssociation < AssociationProxy #:nodoc:
+
+      def initialize(owner, reflection)
+        super
+        @finder_sql = construct_conditions
+        construct_sql
+      end
+
+
       def find(*args)
         options = Base.send(:extract_options_from_args!, args)
 
@@ -15,7 +23,10 @@ module ActiveRecord
         elsif @reflection.options[:order]
           options[:order] = @reflection.options[:order]
         end
-
+        
+        options[:select] = construct_select
+        options[:from]   = construct_from
+        
         merge_options_from_reflection!(options)
 
         # Pass through args exactly as we received them.
@@ -83,10 +94,30 @@ module ActiveRecord
         
         def construct_scope
           {
-            :find   => { :conditions => construct_conditions },
+            :find   => { :from => construct_from, :conditions => construct_conditions },
             :create => { @reflection.primary_key_name => @owner.id }
           }
         end
+        
+        def construct_sql
+          case
+            when @reflection.options[:finder_sql]
+              @finder_sql = interpolate_sql(@reflection.options[:finder_sql])
+
+              @finder_sql = "#{@reflection.klass.table_name}.#{@reflection.primary_key_name} = #{@owner.quoted_id}"
+              @finder_sql << " AND (#{interpolate_sql(@conditions)})" if @conditions
+          end
+
+          if @reflection.options[:counter_sql]
+            @counter_sql = interpolate_sql(@reflection.options[:counter_sql])
+          elsif @reflection.options[:finder_sql]
+            @reflection.options[:counter_sql] = @reflection.options[:finder_sql].gsub(/SELECT (.*) FROM/i, "SELECT COUNT(*) FROM")
+            @counter_sql = interpolate_sql(@reflection.options[:counter_sql])
+          else
+            @counter_sql = @finder_sql
+          end
+        end
+        
     end
   end
 end
diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index b8925a6ee5..c533b3a873 100755
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -853,7 +853,7 @@ module ActiveRecord #:nodoc:
 
         method_scoping.assert_valid_keys [:find, :create]
         if f = method_scoping[:find]
-          f.assert_valid_keys [:conditions, :joins, :offset, :limit, :readonly]
+          f.assert_valid_keys [:conditions, :joins, :from, :offset, :limit, :readonly]
           f[:readonly] = true if !f[:joins].blank? && !f.has_key?(:readonly)
         end
 
@@ -917,7 +917,7 @@ module ActiveRecord #:nodoc:
 
         def construct_finder_sql(options)
           sql  = "SELECT #{options[:select] || '*'} "
-          sql << "FROM #{options[:from] || table_name} "
+          sql << "FROM #{scope(:find, :from) || options[:from] || table_name} "
 
           add_joins!(sql, options)
           add_conditions!(sql, options[:conditions])