These just dispatch the same as calling Zlib::Deflate.deflate and Zlib::Inflate.inflate, but the Zlib-bound versions are not tested anywhere. As a result, we missed adding them in JRuby until now.
This issue was solved with changeset r35540.
Charles, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.
test/zlib/test_zlib.rb (test_inflate): add a test for Zlib.inflate.
patched by headius (Charles Nutter). [ruby-core:44859] [Bug #6398]
test/zlib/test_zlib.rb (test_deflate): add a test for Zlib.deflate.