fails:Warning.warn isn't called by Kernel.warn when category is :deprecated but Warning[:deprecated] is false
fails:Warning.warn isn't called by Kernel.warn when category is :experimental but Warning[:experimental] is false
fails:Warning.warn warns when category is :strict_unused_block but Warning[:strict_unused_block] is false
fails:Warning.warn doesn't print message when category is :strict_unused_block but Warning[:strict_unused_block] is false
windows:Warning.warn does not add a newline
windows:Warning.warn returns nil
windows:Warning.warn can be overridden
fails:Warning.warn is called by parser warnings
