spring/application.rb:161 undefined method `reject!' for nil:NilClass (NoMethodError)
There was an active discussion about this issue few days back here in spring gems repo. The underlying ruby gem binding_of_caller was creating the issue with ruby 2.5.0. The issue is marked as closed with a pr now here in binding_of_caller_repo. So, I think you can simply do a bundle update or bundle update binding_of_caller to fix it. You can also try downgrading ruby to 2.4.3 if that doesn't worked. Hope this helps.