From 9853fa90904be82e71c7e9fd19d99d2177289bad Mon Sep 17 00:00:00 2001
From: Jean-Paul Calderone <exarkun@twistedmatrix.com>
Date: Mon, 10 Aug 2020 09:59:36 -0400
Subject: [PATCH] Pin Python 2 compatible PyInstaller

---
 tox.ini | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tox.ini b/tox.ini
index 4356cfd24..908d24d54 100644
--- a/tox.ini
+++ b/tox.ini
@@ -210,7 +210,9 @@ extras =
 deps =
     {[testenv]deps}
     packaging
-    pyinstaller
+    # PyInstaller 4.0 drops Python 2 support.  When we finish porting to
+    # Python 3 we can reconsider this constraint.
+    pyinstaller < 4.0
 # Setting PYTHONHASHSEED to a known value assists with reproducible builds.
 # See https://pyinstaller.readthedocs.io/en/stable/advanced-topics.html#creating-a-reproducible-build
 setenv=PYTHONHASHSEED=1