How to fix Jekyll build warnings

Problem:

You are using Jekyll to build your website, and you are getting a few warnings like these when you run the command,

jekyll serve

/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/fileutils/version.rb:4: warning: already initialized constant FileUtils::VERSION
/Library/Ruby/Gems/2.6.0/gems/fileutils-1.4.1/lib/fileutils.rb:105: warning: previous definition of VERSION was here
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/fileutils.rb:1267: warning: already initialized constant FileUtils::Entry_::S_IF_DOOR
/Library/Ruby/Gems/2.6.0/gems/fileutils-1.4.1/lib/fileutils.rb:1284: warning: previous definition of S_IF_DOOR was here
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/fileutils.rb:1540: warning: already initialized constant FileUtils::Entry_::DIRECTORY_TERM
/Library/Ruby/Gems/2.6.0/gems/fileutils-1.4.1/lib/fileutils.rb:1568: warning: previous definition of DIRECTORY_TERM was here
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/fileutils.rb:1595: warning: already initialized constant FileUtils::OPT_TABLE
/Library/Ruby/Gems/2.6.0/gems/fileutils-1.4.1/lib/fileutils.rb:1626: warning: previous definition of OPT_TABLE was here
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/fileutils.rb:1649: warning: already initialized constant FileUtils::LOW_METHODS
/Library/Ruby/Gems/2.6.0/gems/fileutils-1.4.1/lib/fileutils.rb:1685: warning: previous definition of LOW_METHODS was here
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/fileutils.rb:1656: warning: already initialized constant FileUtils::METHODS
/Library/Ruby/Gems/2.6.0/gems/fileutils-1.4.1/lib/fileutils.rb:1692: warning: previous definition of METHODS was here
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/universal-darwin19/strscan.bundle: warning: already initialized constant StringScanner::Version
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/universal-darwin19/strscan.bundle: warning: already initialized constant StringScanner::Id

Your error output will most likely be a bit different from the above example but the important error parts to note down are,

warning: already initialized constant...
warning: previous definition was here...

Your site builds and deploys correctly despite these errors but you want to get rid of these errors, don’t you? yes, you do.

Solution:

First remove the file Gemfile.lock from the root of your site.
Next run this command in terminal from the root of your site,

bundle update

This should fix those bugging errors.
Whenever in the future you want to build your site and you have a Gemfile in your site’s root directory you always must build your site with this command,

bundle exec jekyll serve

Cheers!!!

Date: March 25, 2021

Tags: how-to jekyll