3 files changed, 18 insertions, 6 deletions
diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb
index 3b24ed6754..52a538e5b5 100644
--- a/activerecord/lib/active_record/relation/calculations.rb
+++ b/activerecord/lib/active_record/relation/calculations.rb
@@ -189,11 +189,7 @@ module ActiveRecord
       distinct = self.distinct_value
 
       if operation == "count"
-        if select_values.present?
-          column_name ||= select_values.join(", ")
-        else
-          column_name ||= :all
-        end
+        column_name ||= select_for_count
 
         unless arel.ast.grep(Arel::Nodes::OuterJoin).empty?
           distinct = true
@@ -361,6 +357,15 @@ module ActiveRecord
       column ? column.type_cast(value) : value
     end
 
+    # TODO: refactor to allow non-string `select_values` (eg. Arel nodes).
+    def select_for_count
+      if select_values.present?
+        select_values.join(", ")
+      else
+        :all
+      end
+    end
+
     def build_count_subquery(relation, column_name, distinct)
       column_alias = Arel.sql('count_column')
       subquery_alias = Arel.sql('subquery_for_count')
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 1327cc3c34..a27b6abe2e 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -280,7 +280,7 @@ module ActiveRecord
       args.flatten!
       validate_order_args args
 
-      references = args.reject { |arg| Arel::Node === arg }
+      references = args.grep(String)
       references.map! { |arg| arg =~ /^([a-zA-Z]\w*)\.(\w+)/ && $1 }.compact!
       references!(references) if references.any?
 
diff --git a/activerecord/test/cases/relation_test.rb b/activerecord/test/cases/relation_test.rb
index 693b36f35c..c92a20bec3 100644
--- a/activerecord/test/cases/relation_test.rb
+++ b/activerecord/test/cases/relation_test.rb
@@ -227,6 +227,13 @@ module ActiveRecord
       assert_equal ['"posts".name ASC'], relation.order_values
     end
 
+    test "#order! on non-string does not attempt regexp match for references" do
+      obj = Object.new
+      obj.expects(:=~).never
+      assert relation.order!(obj)
+      assert_equal [obj], relation.order_values
+    end
+
     test '#references!' do
       assert relation.references!(:foo).equal?(relation)
       assert relation.references_values.include?('foo')