bpo-32329: Fix -R option for hash randomization (#4873)

bpo-32329, bpo-32030:

* The -R option now turns on hash randomization when the
  PYTHONHASHSEED environment variable is set to 0 Previously, the
  option was ignored.
* sys.flags.hash_randomization is now properly set to 0 when hash
  randomization is turned off by PYTHONHASHSEED=0.
* _PyCoreConfig_ReadEnv() now reads the PYTHONHASHSEED environment
  variable. _Py_HashRandomization_Init() now only apply the
  configuration, it doesn't read PYTHONHASHSEED anymore.

1 files changed, 10 insertions, 2 deletions

diff --git a/Lib/test/test_cmd_line.py b/Lib/test/test_cmd_line.py
index 2aff51b..2b14c30 100644
--- a/Lib/test/test_cmd_line.py
+++ b/Lib/test/test_cmd_line.py
@@ -432,8 +432,16 @@ class CmdLineTest(unittest.TestCase):
 
         # Verify that sys.flags contains hash_randomization
         code = 'import sys; print("random is", sys.flags.hash_randomization)'
-        rc, out, err = assert_python_ok('-c', code)
-        self.assertEqual(rc, 0)
+        rc, out, err = assert_python_ok('-c', code, PYTHONHASHSEED='')
+        self.assertIn(b'random is 1', out)
+
+        rc, out, err = assert_python_ok('-c', code, PYTHONHASHSEED='random')
+        self.assertIn(b'random is 1', out)
+
+        rc, out, err = assert_python_ok('-c', code, PYTHONHASHSEED='0')
+        self.assertIn(b'random is 0', out)
+
+        rc, out, err = assert_python_ok('-R', '-c', code, PYTHONHASHSEED='0')
         self.assertIn(b'random is 1', out)
 
     def test_del___main__(self):