Question

I have form which is built like this:

<%= form_for @location do |f| %>
<%= f.fields_for :product_dates do |d| %>
<%= d.fields_for :products |p| %>
<%= p.text_field :tag_list,"data-pre" => @product.tags.map(&:attributes).to_json %>

Now when i go to the page i get an error when using the line: "data-pre" => @product.tags.map(&:attributes).to_json which is undefined method tags for nil:NilClass but everything is fine when i take it away. This some type of TokenInput bug? Anyone else had to deal with this?

ProductsController:

def new
    @location = Location.new
    product_date = @location.product_dates.build
    product_date.products.build
end

Answer 1

You simply didn’t set your @product variable => it’s nil.

You should show your controller

EDIT:

replace:

<%= p.text_field :tag_list,"data-pre" => @product.tags.map(&:attributes).to_json %>

with:

<%= p.text_field :tag_list,"data-pre" => p.object.tags.map(&:attributes).to_json %>

This should work for edit as well.

It’s really good sense here: you can’t invoke something you didn’t set.