rake db:create gives undefined method `[]' for nil:NilClass error - ruby-on-rails

Question

Postgres 9.3, Ruby 2.1.0
rake db:create isn't making a test database. I already have a production database. I tried using RAILS_ENV=test rake db:create to force it but it returns "test database is not configured.
My database.yml ->
development:
adapter: postgresql
  database: app_prod
  host: localhost
test: &test
  adapter: postgresql
  database: app_test
  host: localhost
cucumber:
<<: *test
production:
  adapter: postgresql
 database: app_prod
  host: localhost
So it is configured. I also tried just using a console createdb app_test to create my test database but I receive the same error when I try to run rake db:test:prepare.
Anyone have any ideas?
this is --trace on db:create:all
** Invoke db:create:all (first_time)
** Invoke db:load_config (first_time)
** Execute db:load_config
** Execute db:create:all
rake aborted!
undefined method `[]' for nil:NilClass
/Users/username/.rvm/rubies/ruby-2.1.0/lib/ruby/gems/2.1.0/gems/activerecord-4.0.3/lib/active_record/tasks/database_tasks.rb:189:in `block in each_local_configuration'
this is trace on db:test:prepare
** Invoke db:test:prepare (first_time)
** Invoke db:load_config (first_time)
** Execute db:load_config
** Execute db:test:prepare
** Invoke db:test:load (first_time)
** Invoke db:test:purge (first_time)
** Invoke environment (first_time)
** Execute environment
** Invoke db:load_config
** Execute db:test:purge
rake aborted!
undefined method `[]' for nil:NilClass
/Users/username/.rvm/rubies/ruby-2.1.0/lib/ruby/gems/2.1.0/gems/activerecord-4.0.3/lib/active_record/tasks/database_tasks.rb:137:in `purge'

Answer 1

Try running this in console
ActiveRecord::Base.configurations
You should get your database configurations.
Line 3 in this method(Line 189 in github) is failing in your case because configuration is nil
def each_local_configuration
ActiveRecord::Base.configurations.each_value do |configuration|
next unless configuration['database']
if local_database?(configuration)
yield configuration
else
$stderr.puts "This task only modifies local databases. #{configuration['database']} is on a remote host."
end
end
end