ssue #19183: Implement PEP 456 'secure and interchangeable hash algorithm'.

Python now uses SipHash24 on all major platforms.

1 files changed, 22 insertions, 1 deletions

diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
index 0565f39..f0c7148 100644
--- a/Lib/test/test_sys.py
+++ b/Lib/test/test_sys.py
@@ -8,6 +8,7 @@ import operator
 import codecs
 import gc
 import sysconfig
+import platform
 
 # count the number of test runs, used to create unique
 # strings to intern in test_intern()
@@ -431,7 +432,7 @@ class SysModuleTest(unittest.TestCase):
         self.assertEqual(type(sys.int_info.sizeof_digit), int)
         self.assertIsInstance(sys.hexversion, int)
 
-        self.assertEqual(len(sys.hash_info), 5)
+        self.assertEqual(len(sys.hash_info), 9)
         self.assertLess(sys.hash_info.modulus, 2**sys.hash_info.width)
         # sys.hash_info.modulus should be a prime; we do a quick
         # probable primality test (doesn't exclude the possibility of
@@ -446,6 +447,26 @@ class SysModuleTest(unittest.TestCase):
         self.assertIsInstance(sys.hash_info.inf, int)
         self.assertIsInstance(sys.hash_info.nan, int)
         self.assertIsInstance(sys.hash_info.imag, int)
+        algo = sysconfig.get_config_var("PY_HASH_ALGORITHM")
+        if sys.hash_info.algorithm in {"fnv", "siphash24"}:
+            self.assertIn(sys.hash_info.hash_bits, {32, 64})
+            self.assertIn(sys.hash_info.seed_bits, {32, 64, 128})
+
+            if algo == 1:
+                self.assertEqual(sys.hash_info.algorithm, "siphash24")
+            elif algo == 2:
+                self.assertEqual(sys.hash_info.algorithm, "fnv")
+            else:
+                processor = platform.processor().lower()
+                if processor in {"sparc", "mips"}:
+                    self.assertEqual(sys.hash_info.algorithm, "fnv")
+                else:
+                    self.assertEqual(sys.hash_info.algorithm, "siphash24")
+        else:
+            # PY_HASH_EXTERNAL
+            self.assertEqual(algo, 0)
+        self.assertGreaterEqual(sys.hash_info.cutoff, 0)
+        self.assertLess(sys.hash_info.cutoff, 8)
 
         self.assertIsInstance(sys.maxsize, int)
         self.assertIsInstance(sys.maxunicode, int)