bpo-30746: Prohibited the '=' character in environment variable names (#2382)

in `os.putenv()` and `os.spawn*()`.

Lib/test/test_os.py

@@ -2382,6 +2382,55 @@ class SpawnTests(unittest.TestCase):
         self.assertRaises(ValueError, os.spawnve, os.P_NOWAIT, args[0], ('',), {})
         self.assertRaises(ValueError, os.spawnve, os.P_NOWAIT, args[0], [''], {})
 
+    @requires_os_func('spawnve')
+    def test_spawnve_invalid_env(self):
+        # null character in the enviroment variable name
+        args = [sys.executable, '-c', 'pass']
+        newenv = os.environ.copy()
+        newenv["FRUIT\0VEGETABLE"] = "cabbage"
+        try:
+            exitcode = os.spawnve(os.P_WAIT, args[0], args, newenv)
+        except ValueError:
+            pass
+        else:
+            self.assertEqual(exitcode, 127)
+
+        # null character in the enviroment variable value
+        args = [sys.executable, '-c', 'pass']
+        newenv = os.environ.copy()
+        newenv["FRUIT"] = "orange\0VEGETABLE=cabbage"
+        try:
+            exitcode = os.spawnve(os.P_WAIT, args[0], args, newenv)
+        except ValueError:
+            pass
+        else:
+            self.assertEqual(exitcode, 127)
+
+        # equal character in the enviroment variable name
+        args = [sys.executable, '-c', 'pass']
+        newenv = os.environ.copy()
+        newenv["FRUIT=ORANGE"] = "lemon"
+        try:
+            exitcode = os.spawnve(os.P_WAIT, args[0], args, newenv)
+        except ValueError:
+            pass
+        else:
+            self.assertEqual(exitcode, 127)
+
+        # equal character in the enviroment variable value
+        filename = support.TESTFN
+        self.addCleanup(support.unlink, filename)
+        with open(filename, "w") as fp:
+            fp.write('import sys, os\n'
+                     'if os.getenv("FRUIT") != "orange=lemon":\n'
+                     '    raise AssertionError')
+        args = [sys.executable, filename]
+        newenv = os.environ.copy()
+        newenv["FRUIT"] = "orange=lemon"
+        exitcode = os.spawnve(os.P_WAIT, args[0], args, newenv)
+        self.assertEqual(exitcode, 0)
+
+
 # The introduction of this TestCase caused at least two different errors on
 # *nix buildbots. Temporarily skip this to let the buildbots move along.
 @unittest.skip("Skip due to platform/environment differences on *NIX buildbots")