Adapt test for build --without-doc-strings.

Lib/test/test_bytes.py

@@ -925,6 +925,7 @@ class AssortedBytesTest(unittest.TestCase):
         self.assertEqual(bytes(b"abc") < b"ab", False)
         self.assertEqual(bytes(b"abc") <= b"ab", False)
 
+    @test.test_support.requires_docstrings
     def test_doc(self):
         self.assertIsNotNone(bytearray.__doc__)
         self.assertTrue(bytearray.__doc__.startswith("bytearray("), bytearray.__doc__)

Lib/test/test_support.py

@@ -20,6 +20,7 @@ import re
 import time
 import struct
 import _testcapi
+import sysconfig
 try:
     import thread
 except ImportError:
@@ -1111,6 +1112,10 @@ def requires_resource(resource):
     else:
         return unittest.skip("resource {0!r} is not enabled".format(resource))
 
+requires_docstrings = unittest.skipUnless(
+    sysconfig.get_config_var('WITH_DOC_STRINGS'),
+    "test requires docstrings")
+
 def cpython_only(test):
     """
     Decorator for tests only applicable on CPython.