diff --git a/libexec/bats-exec-test b/libexec/bats-exec-test
index 734f874..c9e0a7e 100755
--- a/libexec/bats-exec-test
+++ b/libexec/bats-exec-test
@@ -26,7 +26,7 @@ else
   shift
 fi
 
-BATS_TEST_DIRNAME="$(dirname "$BATS_TEST_FILENAME")"
+BATS_TEST_DIRNAME="${BATS_TEST_FILENAME%/*}"
 BATS_TEST_NAMES=()
 
 load() {