Ruby version 2.4.0 (~Dec 2016) unified Fixnum and Bignum into Integer and deprecated Fixnum. You're probably using ruby version 2.4.0 or later. Your version 1.13.2 of the roo gem is older than that (~Dec 2013) and is using Fixnum. Thus you get the warning.
Your code will still run fine for now with the warning, but if you want to get rid of it, you could upgrade your roo gem. The latest version is 2.8.3 (Feb 2020). If you do upgrade, you may have some code changes to do depending upon what may have changed in the newer version of the gem.
Ruby version 2.4.0 (~Dec 2016) unified
FixnumandBignumintoIntegerand deprecatedFixnum. You're probably using ruby version 2.4.0 or later. Your version 1.13.2 of theroogem is older than that (~Dec 2013) and is usingFixnum. Thus you get the warning.Your code will still run fine for now with the warning, but if you want to get rid of it, you could upgrade your
roogem. The latest version is 2.8.3 (Feb 2020). If you do upgrade, you may have some code changes to do depending upon what may have changed in the newer version of the gem.