bpo-39413: Implement os.unsetenv() on Windows (GH-18104)

The os.unsetenv() function is now also available on Windows.

It is implemented with SetEnvironmentVariableW(name, NULL).

1 files changed, 3 insertions, 8 deletions

diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index 82c441c..50535da 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -956,14 +956,9 @@ class EnvironTests(mapping_tests.BasicTestMappingProtocol):
     # On OS X < 10.6, unsetenv() doesn't return a value (bpo-13415).
     @support.requires_mac_ver(10, 6)
     def test_unset_error(self):
-        if sys.platform == "win32":
-            # an environment variable is limited to 32,767 characters
-            key = 'x' * 50000
-            self.assertRaises(ValueError, os.environ.__delitem__, key)
-        else:
-            # "=" is not allowed in a variable name
-            key = 'key='
-            self.assertRaises(OSError, os.environ.__delitem__, key)
+        # "=" is not allowed in a variable name
+        key = 'key='
+        self.assertRaises(OSError, os.environ.__delitem__, key)
 
     def test_key_type(self):
         missing = 'missingkey'