Test that PostgreSQL adapter includes `usec` when quoting `DateTime`

activerecord/CHANGELOG.md

+*   Test that PostgreSQL adapter includes `usec` when quoting `DateTime` objects
+
+    *Ben Cherry*
+
 *   Fix PredicateBuilder so polymorhic association keys in `where` clause can
     also accept not only `ActiveRecord::Base` direct descendances (decorated
     models, for example).

activerecord/test/cases/adapters/postgresql/quoting_test.rb

@@ -52,6 +52,11 @@ def test_quote_cast_numeric
           c = Column.new(nil, nil, 'text')
           assert_equal "'666'", @conn.quote(fixnum, c)
         end
+
+        def test_quote_time_usec
+          assert_equal "'1970-01-01 00:00:00.000000'", @conn.quote(Time.at(0))
+          assert_equal "'1970-01-01 00:00:00.000000'", @conn.quote(Time.at(0).to_datetime)
+        end
       end
     end
   end