preserve the backtrace of the exception

activerecord/lib/active_record/fixtures.rb

@@ -724,7 +724,7 @@ def yaml_fixtures_key(path)
       def parse_yaml_string(fixture_content)
         YAML::load(erb_render(fixture_content))
       rescue *RESCUE_ERRORS => error
-        raise Fixture::FormatError, "a YAML error occurred parsing #{yaml_file_path}. Please note that YAML must be consistently indented using spaces. Tabs are not allowed. Please have a look at http://www.yaml.org/faq.html\nThe exact error was:\n  #{error.class}: #{error}"
+        raise Fixture::FormatError, "a YAML error occurred parsing #{yaml_file_path}. Please note that YAML must be consistently indented using spaces. Tabs are not allowed. Please have a look at http://www.yaml.org/faq.html\nThe exact error was:\n  #{error.class}: #{error}", error.backtrace
       end
 
       def erb_render(fixture_content)