1 files changed, 7 insertions, 0 deletions
diff --git a/activemodel/test/cases/type/decimal_test.rb b/activemodel/test/cases/type/decimal_test.rb
index 353dbf84ad..1950566c0e 100644
--- a/activemodel/test/cases/type/decimal_test.rb
+++ b/activemodel/test/cases/type/decimal_test.rb
@@ -52,6 +52,13 @@ module ActiveModel
         assert_not type.changed?(5.0, 5.0, '5.0')
         assert_not type.changed?(-5.0, -5.0, '-5.0')
       end
+
+      def test_scale_is_applied_before_precision_to_prevent_rounding_errors
+        type = Decimal.new(precision: 5, scale: 3)
+
+        assert_equal BigDecimal("1.250"), type.cast(1.250473853637869)
+        assert_equal BigDecimal("1.250"), type.cast("1.250473853637869")
+      end
     end
   end
 end