From 159974cc59de459cfb3e31ba3e1d8f279734f66d Mon Sep 17 00:00:00 2001
From: Shantanu <12621235+hauntsaninja@users.noreply.github.com>
Date: Tue, 15 Oct 2024 01:48:34 -0700
Subject: [PATCH] Use sha1 for hashing (#17953)

This is a pretty small win, it's below the noise floor on
macrobenchmark, but if you time the hashing specifically it saves about
100ms (0.5%) on `python -m mypy -c 'import torch' --no-incremental`.
blake2b is slower
---
 mypy/util.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/mypy/util.py b/mypy/util.py
index 4b1b918b92e6..75b3e9101731 100644
--- a/mypy/util.py
+++ b/mypy/util.py
@@ -535,9 +535,7 @@ def hash_digest(data: bytes) -> str:
     accidental collision, but we don't really care about any of the
     cryptographic properties.
     """
-    # Once we drop Python 3.5 support, we should consider using
-    # blake2b, which is faster.
-    return hashlib.sha256(data).hexdigest()
+    return hashlib.sha1(data).hexdigest()
 
 
 def parse_gray_color(cup: bytes) -> str: