collection_select, undefined method `map' for nil:NilClass

Question

I added in the @user = User.new line to make sure it isn\'t nil. Which object is nil?

undefined method `map\' for nil:NilClass

Extracted source         


        

Answer 1

You must to add @user_array to the actions: create, new, edit and update, the best way is using before_actions

before_action :set_user_array , only: [:edit, :update, :new, :create]

 private
    def set_user_array 
      @user_array = User.all 
    end

Answer 2

@user_array is nil. Make sure it's set with an array of users to avoid this error message.

Alternatively, set @user_array to [] (an empty array) if you wish to show no options in the `select, e.g.:

collection_select @user, :full_name, @user_array || [], :id, 
  { prompt: 'true' }, { class: 'select' }