1 files changed, 8 insertions, 0 deletions
diff --git a/test/ruby/test_lazy_enumerator.rb b/test/ruby/test_lazy_enumerator.rb
index 754b6aa8e0..8c03c700c3 100644
--- a/test/ruby/test_lazy_enumerator.rb
+++ b/test/ruby/test_lazy_enumerator.rb
@@ -328,5 +328,13 @@ EOS
     lazy = [1, 2, 3].lazy
     assert_equal 3, lazy.size
     assert_equal 42, Enumerator.new(42){}.lazy.size
+    %i[map collect flat_map collect_concat].each do |m|
+      assert_equal 3, lazy.send(m){}.size
+    end
+    assert_equal 3, lazy.zip([4]).size
+    %i[select find_all reject take_while drop_while].each do |m|
+      assert_equal nil, lazy.send(m){}.size
+    end
+    assert_equal nil, lazy.grep(//).size
   end
 end