Merge branch 'master' into nested_has_many_through

Conflicts:
	activerecord/CHANGELOG
	activerecord/lib/active_record/association_preload.rb
	activerecord/lib/active_record/associations.rb
	activerecord/lib/active_record/associations/class_methods/join_dependency.rb
	activerecord/lib/active_record/associations/class_methods/join_dependency/join_association.rb
	activerecord/lib/active_record/associations/has_many_association.rb
	activerecord/lib/active_record/associations/has_many_through_association.rb
	activerecord/lib/active_record/associations/has_one_association.rb
	activerecord/lib/active_record/associations/has_one_through_association.rb
	activerecord/lib/active_record/associations/through_association_scope.rb
	activerecord/lib/active_record/reflection.rb
	activerecord/test/cases/associations/has_many_through_associations_test.rb
	activerecord/test/cases/associations/has_one_through_associations_test.rb
	activerecord/test/cases/reflection_test.rb
	activerecord/test/cases/relations_test.rb
	activerecord/test/fixtures/memberships.yml
	activerecord/test/models/categorization.rb
	activerecord/test/models/category.rb
	activerecord/test/models/member.rb
	activerecord/test/models/reference.rb
	activerecord/test/models/tagging.rb

1 files changed, 28 insertions, 24 deletions

diff --git a/activerecord/lib/active_record/associations/alias_tracker.rb b/activerecord/lib/active_record/associations/alias_tracker.rb
index 6428fcec0a..6fc2bfdb31 100644
--- a/activerecord/lib/active_record/associations/alias_tracker.rb
+++ b/activerecord/lib/active_record/associations/alias_tracker.rb
@@ -5,32 +5,44 @@ module ActiveRecord
     # Keeps track of table aliases for ActiveRecord::Associations::ClassMethods::JoinDependency and
     # ActiveRecord::Associations::ThroughAssociationScope
     class AliasTracker # :nodoc:
+      attr_reader :aliases, :table_joins
+
       # table_joins is an array of arel joins which might conflict with the aliases we assign here
-      def initialize(table_joins = nil)
+      def initialize(table_joins = [])
         @aliases     = Hash.new
         @table_joins = table_joins
       end
 
+      def aliased_table_for(table_name, aliased_name = nil)
+        table_alias = aliased_name_for(table_name, aliased_name)
+
+        if table_alias == table_name # TODO: Is this conditional necessary?
+          Arel::Table.new(table_name)
+        else
+          Arel::Table.new(table_name).alias(table_alias)
+        end
+      end
+
       def aliased_name_for(table_name, aliased_name = nil)
         aliased_name ||= table_name
 
-        initialize_count_for(table_name) if @aliases[table_name].nil?
+        initialize_count_for(table_name) if aliases[table_name].nil?
 
-        if @aliases[table_name].zero?
+        if aliases[table_name].zero?
           # If it's zero, we can have our table_name
-          @aliases[table_name] = 1
+          aliases[table_name] = 1
           table_name
         else
           # Otherwise, we need to use an alias
           aliased_name = connection.table_alias_for(aliased_name)
 
-          initialize_count_for(aliased_name) if @aliases[aliased_name].nil?
+          initialize_count_for(aliased_name) if aliases[aliased_name].nil?
 
           # Update the count
-          @aliases[aliased_name] += 1
+          aliases[aliased_name] += 1
 
-          if @aliases[aliased_name] > 1
-            "#{truncate(aliased_name)}_#{@aliases[aliased_name]}"
+          if aliases[aliased_name] > 1
+            "#{truncate(aliased_name)}_#{aliases[aliased_name]}"
           else
             aliased_name
           end
@@ -44,29 +56,21 @@ module ActiveRecord
       private
 
         def initialize_count_for(name)
-          @aliases[name] = 0
+          aliases[name] = 0
 
-          unless @table_joins.nil? || Arel::Table === @table_joins
+          unless Arel::Table === table_joins
             # quoted_name should be downcased as some database adapters (Oracle) return quoted name in uppercase
             quoted_name = connection.quote_table_name(name).downcase
 
-            @aliases[name] += @table_joins.grep(Arel::Nodes::Join).map { |join|
-              right = join.right
-              case right
-              when Arel::Table
-                right.name.downcase == name ? 1 : 0
-              when String
-                # Table names + table aliases
-                right.downcase.scan(
-                  /join(?:\s+\w+)?\s+(\S+\s+)?#{quoted_name}\son/
-                ).size
-              else
-                0
-              end
+            aliases[name] += table_joins.map { |join|
+              # Table names + table aliases
+              join.left.downcase.scan(
+                /join(?:\s+\w+)?\s+(\S+\s+)?#{quoted_name}\son/
+              ).size
             }.sum
           end
 
-          @aliases[name]
+          aliases[name]
         end
 
         def truncate(name)