1 files changed, 26 insertions, 17 deletions

diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 6cf57b679d..7d2b427289 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -120,6 +120,9 @@ module ActiveRecord
     # Will throw an error, but this will work:
     #
     #   User.includes(:posts).where('posts.name = ?', 'example').references(:posts)
+    #
+    # Note that +includes+ works with association names while +references+ needs
+    # the actual table name.
     def includes(*args)
       check_if_method_has_arguments!(:includes, args)
       spawn.includes!(*args)
@@ -163,24 +166,26 @@ module ActiveRecord
       self
     end
 
-    # Used to indicate that an association is referenced by an SQL string, and should
-    # therefore be JOINed in any query rather than loaded separately.
+    # Use to indicate that the given +table_names+ are referenced by an SQL string,
+    # and should therefore be JOINed in any query rather than loaded separately.
+    # This method only works in conjuction with +includes+.
+    # See #includes for more details.
     #
     #   User.includes(:posts).where("posts.name = 'foo'")
     #   # => Doesn't JOIN the posts table, resulting in an error.
     #
     #   User.includes(:posts).where("posts.name = 'foo'").references(:posts)
     #   # => Query now knows the string references posts, so adds a JOIN
-    def references(*args)
-      check_if_method_has_arguments!(:references, args)
-      spawn.references!(*args)
+    def references(*table_names)
+      check_if_method_has_arguments!(:references, table_names)
+      spawn.references!(*table_names)
     end
 
-    def references!(*args) # :nodoc:
-      args.flatten!
-      args.map!(&:to_s)
+    def references!(*table_names) # :nodoc:
+      table_names.flatten!
+      table_names.map!(&:to_s)
 
-      self.references_values |= args
+      self.references_values |= table_names
       self
     end
 
@@ -234,7 +239,9 @@ module ActiveRecord
 
     def select!(*fields) # :nodoc:
       fields.flatten!
-
+      fields.map! do |field|
+        klass.attribute_alias?(field) ? klass.attribute_alias(field).to_sym : field
+      end
       self.select_values += fields
       self
     end
@@ -817,11 +824,12 @@ module ActiveRecord
     end
 
     # Returns the Arel object associated with the relation.
-    def arel
+    def arel # :nodoc:
       @arel ||= build_arel
     end
 
-    # Like #arel, but ignores the default scope of the model.
+    private
+
     def build_arel
       arel = Arel::SelectManager.new(table.engine, table)
 
@@ -856,8 +864,6 @@ module ActiveRecord
       arel
     end
 
-    private
-
     def symbol_unscoping(scope)
       if !VALID_UNSCOPING_VALUES.include?(scope)
         raise ArgumentError, "Called unscope() with invalid unscoping argument ':#{scope}'. Valid arguments are :#{VALID_UNSCOPING_VALUES.to_a.join(", :")}."
@@ -887,8 +893,6 @@ module ActiveRecord
         when Arel::Nodes::In, Arel::Nodes::NotIn, Arel::Nodes::Equality, Arel::Nodes::NotEqual
           subrelation = (rel.left.kind_of?(Arel::Attributes::Attribute) ? rel.left : rel.right)
           subrelation.name == target_value
-        else
-          raise "unscope(where: #{target_value.inspect}) failed: unscoping #{rel.class} is unimplemented."
         end
       end
 
@@ -1022,7 +1026,10 @@ module ActiveRecord
 
     def build_select(arel, selects)
       if !selects.empty?
-        arel.project(*selects)
+        expanded_select = selects.map do |field|
+          columns_hash.key?(field.to_s) ? arel_table[field] : field
+        end
+        arel.project(*expanded_select)
       elsif from_value
         arel.project(Arel.star)
       else
@@ -1080,9 +1087,11 @@ module ActiveRecord
       order_args.map! do |arg|
         case arg
         when Symbol
+          arg = klass.attribute_alias(arg).to_sym if klass.attribute_alias?(arg)
           table[arg].asc
         when Hash
           arg.map { |field, dir|
+            field = klass.attribute_alias(field).to_sym if klass.attribute_alias?(field)
             table[field].send(dir)
           }
         else