bpo-37201: fix test_distutils failures for Windows ARM64 (GH-13902)

_msvccompiler.py

@@ -93,6 +93,7 @@ PLAT_SPEC_TO_RUNTIME = {
     'x86' : 'x86',
     'x86_amd64' : 'x64',
     'x86_arm' : 'arm',
+    'x86_arm64' : 'arm64'
 }
 
 def _find_vcvarsall(plat_spec):
@@ -190,6 +191,7 @@ PLAT_TO_VCVARS = {
     'win32' : 'x86',
     'win-amd64' : 'x86_amd64',
     'win-arm32' : 'x86_arm',
+    'win-arm64' : 'x86_arm64'
 }
 
 # A set containing the DLLs that are guaranteed to be available for

tests/test_bdist_wininst.py

 """Tests for distutils.command.bdist_wininst."""
+import sys
+import platform
 import unittest
 from test.support import run_unittest
 
 from distutils.command.bdist_wininst import bdist_wininst
 from distutils.tests import support
 
+@unittest.skipIf(sys.platform == 'win32' and platform.machine() == 'ARM64',
+    'bdist_wininst is not supported in this install')
 @unittest.skipIf(getattr(bdist_wininst, '_unsupported', False),
     'bdist_wininst is not supported in this install')
 class BuildWinInstTestCase(support.TempdirManager,

util.py

@@ -40,6 +40,8 @@ def get_host_platform():
             return 'win-amd64'
         if '(arm)' in sys.version.lower():
             return 'win-arm32'
+        if '(arm64)' in sys.version.lower():
+            return 'win-arm64'
         return sys.platform
 
     # Set for cross builds explicitly