diff --git a/cmd/ninja/cmd/plugin_test.go b/cmd/ninja/cmd/plugin_test.go
index 1ca84c8..8dd3164 100644
--- a/cmd/ninja/cmd/plugin_test.go
+++ b/cmd/ninja/cmd/plugin_test.go
@@ -203,6 +203,9 @@ func TestGitignoredTrackedWarning_FiresWhenTrackedFileMatchesGitignore(t *testin
 	if !strings.Contains(out, "git rm --cached") {
 		t.Errorf("warning should suggest `git rm --cached`, got: %q", out)
 	}
+	if !strings.HasSuffix(out, "\n") {
+		t.Errorf("warning should end with a newline (Fprintln), got: %q", out)
+	}
 }
 
 func TestGitignoredTrackedWarning_NoopWhenNothingMatches(t *testing.T) {