From 5e30fdf0fe140f599fb19534d2373d25c2756fe7 Mon Sep 17 00:00:00 2001
From: Ian Paschal <ian.paschal@gmail.com>
Date: Mon, 9 Jul 2018 15:54:54 +0200
Subject: [PATCH] Make sure searchPath is always a string

---
 run_mypy.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/run_mypy.py b/run_mypy.py
index 2a2c72dbbe..43196fa7f1 100644
--- a/run_mypy.py
+++ b/run_mypy.py
@@ -5,6 +5,8 @@ import subprocess
 
 # A quick Python implementation of unix 'where' command.
 def where(exeName, searchPath=os.getenv("PATH")):
+    if searchPath is None:
+        searchPath = ""
     paths = searchPath.split(";" if sys.platform == "win32" else ":")
     for path in paths:
         candidatePath = os.path.join(path, exeName)