diff --git a/test/preamble.rb b/test/preamble.rb
index 7ea746c..7cfdea6 100644
--- a/test/preamble.rb
+++ b/test/preamble.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'minitest/autorun'
-$:.unshift(File.expand_path("../ext", __dir__))
-require 'tedrahcu'
\ No newline at end of file
+$LOAD_PATH.unshift(File.expand_path('../ext', __dir__))
+require 'tedrahcu'