diff --git a/phpunit/bootstrap.php b/phpunit/bootstrap.php
index 6b955be13f585..60fa04f5af1c7 100644
--- a/phpunit/bootstrap.php
+++ b/phpunit/bootstrap.php
@@ -5,17 +5,17 @@
  * @package Gutenberg
  */
 
-// Determine the tests directory (from a WP dev checkout)
-// Try the WP_TESTS_DIR environment variable first
+// Determine the tests directory (from a WP dev checkout).
+// Try the WP_TESTS_DIR environment variable first.
 $_tests_dir = getenv( 'WP_TESTS_DIR' );
-// See if we're installed inside an existing WP dev instance
+// See if we're installed inside an existing WP dev instance.
 if ( ! $_tests_dir ) {
 	$_try_tests_dir = __DIR__ . '/../../../../../tests/phpunit';
 	if ( file_exists( $_try_tests_dir . '/includes/functions.php' ) ) {
 		$_tests_dir = $_try_tests_dir;
 	}
 }
-// Fallback
+// Fallback.
 if ( ! $_tests_dir ) {
 	$_tests_dir = '/tmp/wordpress-tests-lib';
 }