From 56e5a09db6011de95165510e71e3ffc5cb86c692 Mon Sep 17 00:00:00 2001
From: Milan Stute <mstute@seemoo.tu-darmstadt.de>
Date: Thu, 19 Dec 2019 09:06:26 +0100
Subject: [PATCH] Check for virtualenv in Makefile

---
 Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Makefile b/Makefile
index 281a376..ccaf006 100644
--- a/Makefile
+++ b/Makefile
@@ -8,6 +8,9 @@ ci: checkformat lint test
 $(VENV): $(VENV)/bin/activate
 
 $(VENV)/bin/activate: setup.py requirements-dev.txt Makefile
+ifeq (, $(shell which virtualenv))
+	$(error "`virtualenv` is not installed, consider running `pip3 install virtualenv`")
+endif
 	test -d $(VENV) || virtualenv -p python3 $(VENV)
 	$(PYTHON) -m pip install --upgrade pip
 	$(PYTHON) -m pip install -r requirements-dev.txt