Rails 4 rake db:seed returns no implicit conversion of nil into String

Question

when running rake db:seed to put in a test user, i get the following error:

ROLES
rake aborted!
no implicit conversion of nil into String
/Users/joshburns/Code/file-server/db/seeds.rb:10:in `<top (required)>'
/Users/joshburns/.rvm/gems/ruby-2.1.0@file-server/gems/activesupport-4.0.3/lib/active_support/dependencies.rb:223:in `load'
/Users/joshburns/.rvm/gems/ruby-2.1.0@file-server/gems/activesupport-4.0.3/lib/active_support/dependencies.rb:223:in `block in load'
/Users/joshburns/.rvm/gems/ruby-2.1.0@file-server/gems/activesupport-4.0.3/lib/active_support/dependencies.rb:214:in `load_dependency'
/Users/joshburns/.rvm/gems/ruby-2.1.0@file-server/gems/activesupport-4.0.3/lib/active_support/dependencies.rb:223:in `load'
/Users/joshburns/.rvm/gems/ruby-2.1.0@file-server/gems/railties-4.0.3/lib/rails/engine.rb:540:in `load_seed'
/Users/joshburns/.rvm/gems/ruby-2.1.0@file-server/gems/activerecord-4.0.3/lib/active_record/tasks/database_tasks.rb:154:in `load_seed'
/Users/joshburns/.rvm/gems/ruby-2.1.0@file-server/gems/activerecord-4.0.3/lib/active_record/railties/databases.rake:181:in `block (2 levels) in <top (required)>'
Tasks: TOP => db:seed
(See full trace by running task with --trace)

my seeds file:

puts 'ROLES'
YAML.load(ENV['ROLES']).each do |role|
  Role.find_or_create_by_name(role)
  puts 'role: ' << role
end
puts 'DEFAULT USERS'
user = User.find_or_create_by_email :name => ENV['ADMIN_NAME'].dup, :email => ENV['ADMIN_EMAIL'].dup, :password => ENV['ADMIN_PASSWORD'].dup, :password_confirmation => ENV['ADMIN_PASSWORD'].dup
puts 'user: ' << user.name
user.add_role :admin

Answer 1

If this is your seeds.db file, why are you outputting strings?

puts 'ROLES'
puts 'DEFAULT USERS'
puts 'user: ' << user.name

seeds.rb is the same as rake tasks, models & controllers - they don't render anything directly to the user

Although we'd need to see more of your code, I'd do this:

YAML.load(ENV['ROLES']).each do |role|
  Role.find_or_create_by_name(role)
  puts 'role: ' << role
end
user = User.find_or_create_by_email :name => ENV['ADMIN_NAME'], :email => ENV['ADMIN_EMAIL'], :password => ENV['ADMIN_PASSWORD'], :password_confirmation => ENV['ADMIN_PASSWORD']

user.add_role :admin #-> need to see your method

If you're looking to make your seeds.rb file readable, you should use comments to split it up