diff --git a/test/integration/oni-conf.bats b/test/integration/oni-conf.bats
index aa1cc88..6deb0e8 100755
--- a/test/integration/oni-conf.bats
+++ b/test/integration/oni-conf.bats
@@ -13,7 +13,7 @@
 @test "Opening a .service file enables conf-mode" {
     run emacs -batch -l package -f package-initialize \
         -visit test.service \
-        -eval "(prin1 (derived-mode-p major-mode 'conf-mode))"
+        -eval "(prin1 (not (null (derived-mode-p major-mode 'conf-mode))))"
 
     echo "$output"