Issue #12549: Correct test_platform to not fail when OS X returns 'x86_64'

as the processor type on some Mac systems.  Also fix NameError in fallback
_mac_ver_gestalt function.  And remove out-of-date URL in docs.

Doc/library/platform.rst

@@ -228,9 +228,6 @@ Mac OS Platform
    Entries which cannot be determined are set to ``''``.  All tuple entries are
    strings.
 
-   Documentation for the underlying :c:func:`gestalt` API is available online at
-   http://www.rgaros.nl/gestalt/.
-
 
 Unix Platforms
 --------------

Lib/platform.py

@@ -758,6 +758,7 @@ def _mac_ver_gestalt():
                    0x2: 'PowerPC',
                    0xa: 'i386'}.get(sysa,'')
 
+    versioninfo=('', '', '')
     return release,versioninfo,machine
 
 def _mac_ver_xml():

Lib/test/test_platform.py

@@ -194,7 +194,7 @@ class PlatformTest(unittest.TestCase):
             self.assertEqual(res[1], ('', '', ''))
 
             if sys.byteorder == 'little':
-                self.assertEqual(res[2], 'i386')
+                self.assertIn(res[2], ('i386', 'x86_64'))
             else:
                 self.assertEqual(res[2], 'PowerPC')
 

Misc/NEWS

@@ -56,6 +56,9 @@ C-API
 Tests
 -----
 
+- Issue #12549: Correct test_platform to not fail when OS X returns 'x86_64'
+  as the processor type on some Mac systems.
+
 - Avoid failing in test_robotparser when mueblesmoraleda.com is flaky and
   an overzealous DNS service (e.g. OpenDNS) redirects to a placeholder
   Web site.