From 5a453cb089f811cd7f54fb07972942609690052f Mon Sep 17 00:00:00 2001
From: Eitan Mosenkis <emosenkis@google.com>
Date: Tue, 10 Dec 2019 20:53:27 +0200
Subject: [PATCH] Pin black to 19.3b0 to avoid errors trying to compile regex.

---
 Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 9259be73..3c5efb5d 100644
--- a/Makefile
+++ b/Makefile
@@ -68,7 +68,7 @@ venv:
 	python3 -m venv venv
 	venv/bin/pip -q install --upgrade pip
 	venv/bin/pip -q install --upgrade -r tools/requirements.txt
-	venv/bin/pip -q install --upgrade black
+	venv/bin/pip -q install --upgrade black==19.3b0 # Versions newer than this require regex, which fails to compile
 
 # selectively reformat our own code
 black: venv
@@ -135,4 +135,4 @@ test-docker:
 travis:
 	$(MAKE) test VENV=". ../../venv/bin/activate;"
 	$(MAKE) test-docker
-	$(MAKE) black
\ No newline at end of file
+	$(MAKE) black