Merge commit 'mainstream/master'

4 files changed, 36 insertions, 8 deletions

diff --git a/activerecord/lib/active_record/association_preload.rb b/activerecord/lib/active_record/association_preload.rb
index 61fa34ac39..c60850fc77 100644
--- a/activerecord/lib/active_record/association_preload.rb
+++ b/activerecord/lib/active_record/association_preload.rb
@@ -95,7 +95,7 @@ module ActiveRecord
         records.each {|record| record.send(reflection.name).loaded}
         options = reflection.options
 
-        conditions = "t0.#{reflection.primary_key_name}  IN (?)"
+        conditions = "t0.#{reflection.primary_key_name} #{in_or_equals_for_ids(ids)}"
         conditions << append_conditions(options, preload_options)
 
         associated_records = reflection.klass.find(:all, :conditions => [conditions, ids],
@@ -222,8 +222,6 @@ module ActiveRecord
 
           table_name = klass.quoted_table_name
           primary_key = klass.primary_key
-          conditions = "#{table_name}.#{connection.quote_column_name(primary_key)} IN (?)"
-          conditions << append_conditions(options, preload_options)
           column_type = klass.columns.detect{|c| c.name == primary_key}.type
           ids = id_map.keys.uniq.map do |id|
             if column_type == :integer
@@ -234,6 +232,8 @@ module ActiveRecord
               id
             end
           end
+          conditions = "#{table_name}.#{connection.quote_column_name(primary_key)} #{in_or_equals_for_ids(ids)}"
+          conditions << append_conditions(options, preload_options)
           associated_records = klass.find(:all, :conditions => [conditions, ids],
                                           :include => options[:include],
                                           :select => options[:select],
@@ -248,10 +248,10 @@ module ActiveRecord
         table_name = reflection.klass.quoted_table_name
 
         if interface = reflection.options[:as]
-          conditions = "#{reflection.klass.quoted_table_name}.#{connection.quote_column_name "#{interface}_id"} IN (?) and #{reflection.klass.quoted_table_name}.#{connection.quote_column_name "#{interface}_type"} = '#{self.base_class.sti_name}'"
+          conditions = "#{reflection.klass.quoted_table_name}.#{connection.quote_column_name "#{interface}_id"} #{in_or_equals_for_ids(ids)} and #{reflection.klass.quoted_table_name}.#{connection.quote_column_name "#{interface}_type"} = '#{self.base_class.sti_name}'"
         else
           foreign_key = reflection.primary_key_name
-          conditions = "#{reflection.klass.quoted_table_name}.#{foreign_key} IN (?)"
+          conditions = "#{reflection.klass.quoted_table_name}.#{foreign_key} #{in_or_equals_for_ids(ids)}"
         end
 
         conditions << append_conditions(options, preload_options)
@@ -277,6 +277,9 @@ module ActiveRecord
         sql
       end
 
+      def in_or_equals_for_ids(ids)
+        ids.size > 1 ? "IN (?)" : "= ?"
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb
index aca2d770fc..5d91315aad 100755
--- a/activerecord/lib/active_record/associations.rb
+++ b/activerecord/lib/active_record/associations.rb
@@ -1237,7 +1237,7 @@ module ActiveRecord
 
             association = instance_variable_get(ivar) if instance_variable_defined?(ivar)
 
-            if association.nil? || force_reload
+            if association.nil? || !association.loaded? || force_reload
               association = association_proxy_class.new(self, reflection)
               retval = association.reload
               if retval.nil? and association_proxy_class == BelongsToAssociation
@@ -1266,6 +1266,13 @@ module ActiveRecord
             end
           end
 
+          if association_proxy_class == BelongsToAssociation
+            define_method("#{reflection.primary_key_name}=") do |target_id|
+              instance_variable_get(ivar).reset if instance_variable_defined?(ivar)
+              write_attribute(reflection.primary_key_name, target_id)
+            end
+          end
+
           define_method("set_#{reflection.name}_target") do |target|
             return if target.nil? and association_proxy_class == BelongsToAssociation
             association = association_proxy_class.new(self, reflection)
diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index fc6d762fcd..91b69747e0 100755
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -2152,7 +2152,7 @@ module ActiveRecord #:nodoc:
         end
 
         def quote_bound_value(value) #:nodoc:
-          if value.respond_to?(:map) && !value.is_a?(String)
+          if value.respond_to?(:map) && !value.acts_like?(:string)
             if value.respond_to?(:empty?) && value.empty?
               connection.quote(nil)
             else
diff --git a/activerecord/lib/active_record/dirty.rb b/activerecord/lib/active_record/dirty.rb
index 7e246e62ca..ae573799ae 100644
--- a/activerecord/lib/active_record/dirty.rb
+++ b/activerecord/lib/active_record/dirty.rb
@@ -34,8 +34,10 @@ module ActiveRecord
   #   person.name << 'by'
   #   person.name_change    # => ['uncle bob', 'uncle bobby']
   module Dirty
+    DIRTY_SUFFIXES = ['_changed?', '_change', '_will_change!', '_was']
+
     def self.included(base)
-      base.attribute_method_suffix '_changed?', '_change', '_will_change!', '_was'
+      base.attribute_method_suffix *DIRTY_SUFFIXES
       base.alias_method_chain :write_attribute, :dirty
       base.alias_method_chain :save,            :dirty
       base.alias_method_chain :save!,           :dirty
@@ -44,6 +46,8 @@ module ActiveRecord
 
       base.superclass_delegating_accessor :partial_updates
       base.partial_updates = true
+
+      base.send(:extend, ClassMethods)
     end
 
     # Do any attributes have unsaved changes?
@@ -161,5 +165,19 @@ module ActiveRecord
         old != value
       end
 
+    module ClassMethods
+      def self.extended(base)
+        base.metaclass.alias_method_chain(:alias_attribute, :dirty)
+      end
+
+      def alias_attribute_with_dirty(new_name, old_name)
+        alias_attribute_without_dirty(new_name, old_name)
+        DIRTY_SUFFIXES.each do |suffix|
+          module_eval <<-STR, __FILE__, __LINE__+1
+            def #{new_name}#{suffix}; self.#{old_name}#{suffix}; end
+          STR
+        end
+      end
+    end
   end
 end