Revert 1.170.  Add tests.
diff --git a/Lib/test/test_urllib.py b/Lib/test/test_urllib.py
index 3621476..94f0f9e 100644
--- a/Lib/test/test_urllib.py
+++ b/Lib/test/test_urllib.py
@@ -353,6 +353,12 @@
         self.assertEqual(expect, result,
                          "using quote_plus(): %s != %s" % (expect, result))
 
+    def test_quoting_plus(self):
+        self.assertEqual(urllib.quote_plus('alpha+beta gamma'),
+                         'alpha%2Bbeta+gamma')
+        self.assertEqual(urllib.quote_plus('alpha+beta gamma', '+'),
+                         'alpha+beta+gamma')
+
 class UnquotingTests(unittest.TestCase):
     """Tests for unquote() and unquote_plus()