From 59b5e200a527d5b06223053005c766b653a6142e Mon Sep 17 00:00:00 2001
From: Andrej730 <azhilenkov@gmail.com>
Date: Thu, 25 Sep 2025 09:32:23 +0200
Subject: [PATCH] typing

---
 nix/build-all.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/nix/build-all.py b/nix/build-all.py
index fa6fbe0048..392ebf3648 100644
--- a/nix/build-all.py
+++ b/nix/build-all.py
@@ -188,8 +188,10 @@ def cecho(message, color=NO_COLOR):
     logger.info(f"{color}{message}\033[0m")
 
 
-def which(cmd):
-    for path in os.getenv("PATH").split(":"):
+def which(cmd: str) -> Union[str, None]:
+    PATH = os.getenv("PATH")
+    assert PATH
+    for path in PATH.split(":"):
         if os.path.exists(path) and cmd in os.listdir(path):
             return cmd
     return None