1 files changed, 12 insertions, 0 deletions
diff --git a/test/irb/test_completion.rb b/test/irb/test_completion.rb
index d4072fe892..a765bbf3a5 100644
--- a/test/irb/test_completion.rb
+++ b/test/irb/test_completion.rb
@@ -35,5 +35,17 @@ module TestIRB
     def test_complete_symbol_failure
       assert_nil(IRB::InputCompletor::PerfectMatchedProc.(":aiueo", bind: binding))
     end
+
+    def test_complete_reserved_words
+      candidates = IRB::InputCompletor.retrieve_completion_data("de", bind: binding)
+      %w[def defined?].each do |word|
+        assert_include candidates, word
+      end
+
+      candidates = IRB::InputCompletor.retrieve_completion_data("__", bind: binding)
+      %w[__ENCODING__ __LINE__ __FILE__].each do |word|
+        assert_include candidates, word
+      end
+    end
   end
 end