1 files changed, 1 insertions, 0 deletions

diff --git a/.document b/.document
index 8b4938f8a1..2c68af227d 100644
--- a/.document
+++ b/.document
@@ -18,6 +18,7 @@ gc.rb
 io.rb
 kernel.rb
 numeric.rb
+nilclass.rb
 pack.rb
 ractor.rb
 timev.rb