slather: Script fails ( undefined method `each' for nil:NilClass (NoMethodError)

When I’m running slather, I get this error for Xcode 9.3 / 9.4. It is working for 9.2.

Slathering… /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/profdata_coverage_file.rb:45:in source_file_pathname': undefined method each’ for nil:NilClass (NoMethodError) from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/profdata_coverage_file.rb:197:in ignored?' from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/project.rb:132:in block (2 levels) in profdata_coverage_files’ from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/project.rb:128:in map' from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/project.rb:128:in block in profdata_coverage_files’ from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/project.rb:125:in each' from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/project.rb:125:in profdata_coverage_files’ from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/project.rb:98:in coverage_files' from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/coverage_service/cobertura_xml_output.rb:18:in post’ from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/command/coverage_command.rb:97:in post' from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/lib/slather/command/coverage_command.rb:59:in execute’ from /Library/Ruby/Gems/2.3.0/gems/clamp-0.6.5/lib/clamp/command.rb:67:in run' from /Library/Ruby/Gems/2.3.0/gems/clamp-0.6.5/lib/clamp/subcommand/execution.rb:11:in execute’ from /Library/Ruby/Gems/2.3.0/gems/clamp-0.6.5/lib/clamp/command.rb:67:in run' from /Library/Ruby/Gems/2.3.0/gems/clamp-0.6.5/lib/clamp/command.rb:132:in run’ from /Library/Ruby/Gems/2.3.0/gems/slather-2.4.5/bin/slather:17:in <top (required)>' from /usr/local/bin/slather:22:in load’ from /usr/local/bin/slather:22:in `<main>’