diff --git a/tox.ini b/tox.ini
index ff5c8151..0956986e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -15,7 +15,15 @@ ignore = E201,E202,E221,E251,E265,F403,F821,N805,W503
 max-line-length = 160
 
 [testenv]
-passenv = HOME ARCHFLAGS LDFLAGS CFLAGS INCLUDE LIB LD_LIBRARY_PATH PATH
+passenv =
+    HOME
+    ARCHFLAGS
+    LDFLAGS
+    CFLAGS
+    INCLUDE
+    LIB
+    LD_LIBRARY_PATH
+    PATH
 deps =
     cryptography>=2.6
     gpg==1.10.0