diff --git a/tests/testthat/test-means_by_group.R b/tests/testthat/test-means_by_group.R
index 2dc484a36..943215450 100644
--- a/tests/testthat/test-means_by_group.R
+++ b/tests/testthat/test-means_by_group.R
@@ -3,6 +3,9 @@ test_that("meany_by_group", {
   expect_snapshot(means_by_group(efc, "c12hour", "e42dep"))
   expect_snapshot(means_by_group(efc, "c12hour", "e42dep", ci = 0.99))
   expect_snapshot(means_by_group(efc, "c12hour", "e42dep", ci = NA))
+  expect_snapshot(means_by_group(efc, c("neg_c_7", "c12hour"), "e42dep"))
+  expect_snapshot(means_by_group(efc, c("neg_c_7", "c12hour"), "e42dep", ci = NA))
+  expect_snapshot(means_by_group(efc, c("neg_c_7", "c12hour"), "e42dep", ci = 0.99))
   expect_snapshot(means_by_group(efc$c12hour, efc$e42dep))
   expect_snapshot(means_by_group(efc$c12hour, efc$e42dep, ci = NA))
 })