Ensure that you can still do expressions in calculations (closes #11355) [nbugajski/cavelle]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9043 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/lib/active_record/calculations.rb

@@ -111,6 +111,7 @@ def sum(column_name, options = {})
       #   Person.average(:age) # SELECT AVG(age) FROM people...
       #   Person.minimum(:age, :conditions => ['last_name != ?', 'Drake']) # Selects the minimum age for everyone with a last name other than 'Drake'
       #   Person.minimum(:age, :having => 'min(age) > 17', :group => :last_name) # Selects the minimum age for any family without any minors
+      #   Person.sum("2 * age")
       def calculate(operation, column_name, options = {})
         validate_calculation_options(operation, options)
         column_name     = options[:select] if options[:select]
@@ -155,7 +156,7 @@ def construct_calculation_sql(operation, column_name, options) #:nodoc:
           scope           = scope(:find)
           merged_includes = merge_includes(scope ? scope[:include] : [], options[:include])
           aggregate_alias = column_alias_for(operation, column_name)
-          column_name     = "#{connection.quote_table_name(table_name)}.#{column_name}" unless column_name == "*" || column_name.to_s.include?('.')
+          column_name     = "#{connection.quote_table_name(table_name)}.#{column_name}" if column_names.include?(column_name.to_s)
 
           if operation == 'count'
             if merged_includes.any?

activerecord/test/cases/calculations_test.rb

@@ -256,4 +256,8 @@ def test_count_with_no_parameters_isnt_deprecated
   def test_count_with_too_many_parameters_raises
     assert_raise(ArgumentError) { Account.count(1, 2, 3) }
   end
+
+  def test_should_sum_expression
+    assert_equal "636", Account.sum("2 * credit_limit")
+  end
 end