diff -r 6f70a18313e5 Lib/test/test_pydoc.py
--- a/Lib/test/test_pydoc.py	Sat Jun 07 15:09:36 2014 -0700
+++ b/Lib/test/test_pydoc.py	Sat Jun 07 15:30:53 2014 -0700
@@ -402,6 +402,21 @@
         result, doc_loc = get_pydoc_text(xml.etree)
         self.assertEqual(doc_loc, "", "MODULE DOCS incorrectly includes a link")
 
+    def test_stdin_none(self):
+        previous_stdin = sys.stdin
+        try:
+            with captured_output('stdout') as output:
+                help(1)
+            expected_output = output.getvalue()
+            sys.stdin = None
+            with captured_output('stdout') as output:
+                help(1)
+            actual_output = output.getvalue()
+            if actual_output != expected_output:
+                self.fail("help should work regardless of stdin state")
+        finally:
+            sys.stdin = previous_stdin
+
     def test_non_str_name(self):
         # issue14638
         # Treat illegal (non-str) name like no name