diff --git a/test/plugin/test_in_tail.rb b/test/plugin/test_in_tail.rb
index 8d8fd4eae5..204d45cbff 100644
--- a/test/plugin/test_in_tail.rb
+++ b/test/plugin/test_in_tail.rb
@@ -1615,11 +1615,11 @@ def test_unwatched_files_should_be_removed
       assert_equal(
         {
           files: [],
-          tails: {}
+          tails: []
         },
         {
           files: Dir.glob("#{@tmp_dir}/*.txt"),
-          tails: d.instance.instance_variable_get(:@tails)
+          tails: d.instance.instance_variable_get(:@tails).keys
         }
       )
     ensure